Withdrawals due to adverse events in each of the treatment groups for each study are set forth in the tables below:

        Phase 2 Study.    In June 2007, we randomized the first patient in a Phase 2 double-blind, placebo-controlled, multi-center trial evaluating Serada for the treatment of women with moderate-to-severe menopausal hot flashes. The 124 patient study was fully enrolled in September 2007. In February 2008, we announced positive results of our Phase 2 trial for Serada for moderate-to-severe menopausal hot flashes.

        Study Design.    The study included 124 menopausal women (approximately 30 per group) with recurrent, moderate to severe hot flashes and was conducted at eight sites in the United States. The total study treatment duration after screening and baseline was 13 weeks. The primary objective of the study was to investigate the relationship between blood plasma concentrations of gabapentin observed in menopausal women after administration of Serada and the frequency of hot flashes in those women. The plasma concentration data (pharmacokinetics) and the hot flash frequency and severity data (pharmacodynamics) are being used to construct a PK/PD dose response model designed to identify the dosing regimen to utilize in the Phase 3 program.

        In order to facilitate the generation of an optimal dose response model, patients in each of the three active treatment arms remained on a stable Serada dose for five weeks at an initial dose, followed by five weeks on a stable, incrementally higher dose, as follows.

        Each stable dosing regimen was preceded by a one-week titration period.

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        Efficacy.    Serada demonstrated a reduction in the mean frequency of moderate to severe hot flashes, and in the mean total daily severity of hot flashes, in all active treatment groups. Statistical significance relative to placebo from baseline to the end of the study was observed in the 1800mg and 2400mg treatment groups with regard to frequency, and statistical significance was observed in the 1800mg treatment group with regard to severity. The severity of hot flashes is based on a mean daily composite score, where a moderate hot flash is assigned a score of "2" and a severe hot flash is assigned a score of "3". The primary efficacy outcomes observed in the study are set forth in the table below.

        Safety.    Serada was generally well tolerated in the study, with one, two, one and three patients, respectively, withdrawing due to adverse events from the placebo, 1800mg, 2400mg and 3000mg groups. The most common side effects observed in the study were headache, somnolence, dizziness and nausea. The incidence of those side effects in each of the treatment groups is set forth in the table below.

Collaboration and License Arrangements

        PharmaNova.    In October 2006, we entered into a sublicense agreement with PharmaNova, Inc. Pursuant to the agreement, PharmaNova has granted us an exclusive sublicense, under United States Patent No. 6,310,098, held by the University of Rochester, to develop and commercialize in the United States a product that contains gabapentin as its active pharmaceutical ingredient, and is indicated for the treatment of hot flashes associated with menopause.

        We paid PharmaNova an upfront license fee of $0.5 million upon signing of the agreement and paid an additional $0.5 million upon dosing of the first patient in our Phase 3 trials for the product. We are required to pay PharmaNova $1.0 million upon submission to the FDA of a NDA for the product, and $2.0 million upon FDA approval of an NDA. The agreement provides for royalty payments to PharmaNova on net sales of the product, and for milestone payments upon achievement of annual net sales in excess of certain thresholds. We also paid PharmaNova consultancy fees of $0.3 million over approximately ten months beginning in November 2006.

DM-1992 for Parkinson's Disease

General

        Parkinson's disease is a chronic degenerative disorder that affects nearly one million Americans, with significant growth expected over the next 25 years due to aging population demographics. Nearly 5 million people worldwide are estimated to have Parkinson's. While the average age at onset is 60, disease onset starts by age 40 in an estimated 5 to 10 percent of patients, and people as young as 30 can also be affected.

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Parkinson's Treatments; Target Market

        Current therapies are effective in addressing only the mild/moderate motor symptoms of the disease and have significant long-term side effects. Levodopa/carbidopa is the most common treatment of Parkinson's but currently has limitations with inconsistent efficacy and inconvenient dosing since it absorbed in the upper GI tract. Levodopa/carbidopa is available as a generic (brand name Sinemet) and had approximately 2.7 million prescriptions in the United States in 2010.

Clinical Program

        DM-1992 is our investigative novel gastric retentive extended-release formulation of levodopa/carbidopa. In July 2008, The Michael J. Fox Foundation awarded the Company a preclinical development grant to support the DM-1992 program. In October 2010, we were awarded an additional clinical grant under The Michael J. Fox Foundation Clinical Intervention Awards 2010 program.

        First Phase 1 Study.    In January 2009, we initiated our first Phase 1 pharmacokinetic study in Parkinson's patients designed to provide insight into our formulation strategy for the DM-1992 program. The first Phase 1 trial in DM-1992 was a randomized, open-label crossover study that enrolled 18 patients with stable Parkinson's disease at two leading neurology centers in Russia. The objective of the study was to compare the pharmacokinetics of two distinct formulations of DM-1992 and a generic version of Sinemet CR sustained-release levodopa/carbidopa, as well as the safety and tolerability of the formulations. Patients in the trial received a single dose of each of the three treatments being studied. A dose of the first treatment was administered at the beginning of the study, followed by a dose of a second treatment after 7 to 14 days, and a dose of the third treatment after another 7 to 14 days. Blood samples were drawn during the 24 hour period following administration of each treatment. Patients were allowed to remain on any anti-Parkinson's therapies other than levodopa/carbidopa during the trial.

        In August 2009, we completed the first Phase 1 study. In the study, DM-1992 extended coverage above levodopa's efficacious threshold and extended the time to peak levodopa concentration relative to currently available sustained release levodopa/carbidopa formulations. One of our formulations tested in the study extended the median time at which levodopa blood levels stayed above the efficacious threshold of 300 ng/mL to approximately nine hours, compared to approximately seven hours for the generic version of Sinemet CR tested in the study. The time to median peak levodopa blood levels in the study was extended to four hours, compared to 2.8 hours for the comparator.

        Second Phase 1 Study.    In September 2010, we initiated our second pharmacokinetic-pharmacodynamic Phase 1 study for the DM-1992 program. The second Phase 1 trial in DM-1992 was a randomized, open-label crossover study that enrolled 16 patients with stable Parkinson's disease at two leading neurology centers in Russia. The objective of the study was to compare the pharmacokinetics-pharmacodynamics of two distinct twice-daily formulations of DM-1992 and a generic version of Sinemet CR sustained-release levodopa/carbidopa dosed three-times daily, as well as the safety and tolerability of the formulations. Patients in the trial received a full day's dose of each of the three treatments being studied, two doses of each DM-1992 (460mg levodopa and 150mg carbidopa per dose) twelve hours apart, and three doses of generic levodopa/carbidopa over a 12 hour period (200mg of levodopa and 50mg of carbidopa per dose). During the 24 hour period following administration of each treatment, blood samples were drawn and a standard finger tapping test was given to assess efficacy.

        In February 2011, we completed the second Phase 1 study. In the study, both formulations of DM-1992 maintained therapeutic blood levels of above the efficacious threshold of 300 ng/mL for 24 hours. DM-1992 was well tolerated in the study.

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DM-3458 for Gastroesophageal Reflux Disease

General

        Gastroesophageal reflux disease, or GERD, is a disorder of the digestive system caused by the failure of the lower esophageal sphincter muscle, or LES, to close properly, which permits stomach contents to leak back into the esophagus. When stomach contents pass through the LES into the esophagus, stomach acid causes the burning sensation in the chest or throat known as heartburn. Heartburn that occurs more than twice a week may be GERD. Other symptoms of GERD can include acid indigestion, bad breath, chest pain, hoarseness in the morning, and trouble swallowing. According to the NIDDK, 20% of the US population suffers from GERD.

Clinical Program

        In 2006, we conducted a Phase 1 study designed to provide us with insight into our formulation strategy, and in 2007, we conducted a proof-of-concept study related to our DM-3458 program. No additional DM-3458 clinical studies are currently planned, as we are awaiting the results of our efforts to enter into a development and commercialization partnership for the product candidate.

OTHER RESEARCH AND DEVELOPMENT AND COLLABORATIVE PROGRAMS

        Janssen Pharmaceutica N.V.    In August 2010, the Company entered into a non-exclusive license agreement with Janssen Pharmaceutica N.V. (Janssen), granting Janssen a license to certain patents related to the Company's Acuform drug delivery technology to be used in developing fixed dose combinations of canagliflozin and extended release metformin. Under the terms of the agreement, Janssen was also granted a right of reference to the NDA covering the Company's Glumetza product in Janssen's regulatory filings covering fixed dose combinations of canagliflozin and extended release metformin. The parties also entered into a service agreement under which Depomed is responsible for providing formulation work associated with the fixed dose combination products.

        In August 2010, Janssen paid the Company a $5.0 million upfront license fee and a refundable $1.0 million prepayment for formulation work to be performed under the service agreement. Work performed by the Company under the service agreement is reimbursed by Janssen on an agreed-upon FTE rate per hour plus out-of-pocket expenses.

        Under the license agreement, the Company is also eligible to receive additional development milestones. In September 2010, the Company achieved the first development milestone under the agreement related to formulation work, which triggered a $5.0 milestone from Janssen to the Company. The $5.0 million milestone was received in October 2010.

        The agreement also provides for royalties to the Company on future net sales of Janssen's fixed dosed combinations of canagliflozin and extended release metformin.

        Covidien.    In November 2008, the Company entered into a license agreement with Mallinckrodt, Inc., a subsidiary of Covidien, Ltd. (Covidien) granting Covidien worldwide rights to utilize the Company's Acuform technology for the exclusive development of up to four products containing acetaminophen in combination with opiates.

        In 2008, Covidien paid the Company a total of $5.5 million in upfront fees, representing a $4.0 million upfront license fee and a $1.5 million upfront payment for formulation work to be performed by Depomed under the agreement. Under the agreement, the Company may also receive certain developmental milestone payments totaling $16.0 million per product, if achieved, and is also entitled to receive royalties on sales of the products.

        In October 2009, the first formulation was completed by the Company and delivered to Covidien, which triggered a $0.5 million milestone payment from Covidien received in October 2009. In

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September 2010, the first formulation entered clinical development, which triggered a second $0.5 million milestone related to first formulation under the agreement.

        In December 2009, the Company received a $0.5 million milestone payment from Covidien related to the development of a formulation for the second product candidate under the agreement. Although the milestone payment was received by the Company in December 2009, the development of the second formulation was not completed until September 2010.

        Merck & Co., Inc.    In July 2009, the Company entered into a non-exclusive license agreement with Merck & Co., Inc. (Merck) granting Merck a license to certain patents related to the Company's metformin extended release technology to be used in developing fixed dose combinations of sitagliptin and extended release metformin. Under terms of the agreement, Merck received a non-exclusive license as well as other rights to certain Depomed patents directed to metformin extended release technology. In exchange, the Company received a $10.0 million upfront fee in the third quarter of 2009. The Company is also entitled to receive modest single digit royalties on net product sales for an agreed-upon period.

        In September 2010, Merck filed a New Drug Application (NDA) for the therapeutic candidate under the agreement, triggering a $2.5 million milestone which the Company received in October 2010.

        Boehringer Ingelheim.    In March 2011, the Company entered into a license and service agreement with Boehringer Ingelheim granting Boehringer Ingelheim a license to certain patents related to the Company's Acuform drug delivery technology to be used in developing fixed dose combinations of extended release metformin and proprietary Boehringer Ingelheim compounds in development for type 2 diabetes. Under the terms of the agreement, Boehringer Ingelheim was also granted a right of reference to the NDA covering the Company's Glumetza product and associated data for use in potential regulatory submission processes.

        Under the terms of the agreement, Depomed will receive a $10.0 million upfront license fee, and may receive an additional $2.5 million upon delivery of experimental batches of prototype formulations. The Company is also eligible to receive additional milestone payments based on regulatory filing and approval events, as well as royalties on worldwide net sales of products.

        Depomed is responsible for providing certain initial formulation work associated with the fixed dose combination products. Services performed by the Company under the agreement will be reimbursed by Boehringer Ingelheim on an agreed-upon rate, and out-of-pocket expenses will be reimbursed.

RESEARCH AND DEVELOPMENT EXPENSES

        Our research and development expenses were $20.1 million in 2010, $34.3 million in 2009 and $27.3 million in 2008.

OUR DRUG DELIVERY TECHNOLOGIES

        The Acuform technology is based on our proprietary oral drug delivery technologies and is designed to include formulations of drug-containing polymeric tablets that allow multi-hour delivery of an incorporated drug. Although our formulations are proprietary, the polymers utilized in the Acuform technology are commonly used in the food and drug industries and are included in the list of inert substances approved by the FDA for use in oral pharmaceuticals. By using different formulations of the polymers, we believe that the Acuform technology is able to provide continuous, controlled delivery of drugs of varying molecular complexity and solubility. With the use of different polymers and polymers of varying molecular weight, our Acuform tablet technology can deliver drugs by diffusion, tablet erosion, or from a bi-layer matrix. In addition, our technology allows for the delivery of more than one

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drug from a single tablet. If taken with a meal, these polymeric tablets remain in the stomach for an extended period of time to provide continuous, controlled delivery of an incorporated drug.

        The Acuform technology's design is based in part on principles of human gastric emptying and gastrointestinal transit. Following a meal, liquids and small particles flow continuously from the stomach into the intestine, leaving behind the larger undigested particles until the digestive process is complete. As a result, drugs in liquid or dissolved form or those consisting of small particles tend to empty rapidly from the stomach and continue into the small intestine and on into the large intestine, often before the drug has time to act locally or to be absorbed in the stomach and/or upper small intestine. The drug-containing polymeric tablets of the Acuform technology are formulated into easily swallowed shapes and are designed to swell upon ingestion. The tablets attain a size after ingestion sufficient to be retained in the stomach for multiple hours during the digestive process while delivering the drug content at a controlled rate. After drug delivery is complete, the polymeric tablet dissolves and becomes a watery gel, which is safely eliminated through the intestine sight unseen.

        The following graphic demonstrates the operation of the Acuform technology.

        The Acuform technology is designed to address certain limitations of drug delivery and to provide for orally-administered, conveniently-dosed, cost-effective drug therapy that provides continuous, controlled-delivery of a drug over a multi-hour period. We believe that the Acuform technology can provide one or more of the following advantages over conventional methods of drug administration:

•

Greater Patient and Caregiver Convenience.  We believe that the Acuform technology may offer once-daily or reduced frequency dosing for certain drugs that are currently required to be administered several times daily. Less frequent dosing promotes compliance with dosing

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regimens. Patient noncompliance with dosing regimens has been associated with increased costs of medical therapies by prolonging treatment duration, increasing the likelihood of secondary or tertiary disease manifestation and contributing to over-utilization of medical personnel and facilities. By improving patient compliance, providers and third-party payers may reduce unnecessary expenditures and improve therapeutic outcomes.

•

Enhanced Safety and Efficacy through Controlled Delivery.  We believe that the Acuform technology may improve the ratio of therapeutic effect to toxicity by decreasing the initial peak concentrations of a drug associated with toxicity, while maintaining levels of the drug at therapeutic, subtoxic concentrations for an extended period of time. Many drugs demonstrate optimal efficacy when concentrations are maintained at therapeutic levels over an extended period of time. When a drug is administered intermittently, the therapeutic concentration is often exceeded for some period after which concentrations fall below therapeutic levels. Excessively high concentrations are a major cause of side effects and subtherapeutic concentrations are ineffective.



•

Proprietary Reformulation of Generic Products.  We believe that the Acuform technology may offer the potential to produce improved formulations of off-patent drugs. These proprietary formulations may be differentiated from existing generic products by virtue of reduced dosing requirements, improved efficacy, decreased toxicity or additional indications.



•

More Efficient Gastrointestinal Drug Absorption.  We believe that the Acuform technology can be used for improved oral administration of drugs that are inadequately absorbed when delivered as conventional tablets or capsules. Many drugs are primarily absorbed in the stomach, duodenum or upper small intestine regions, through which drugs administered in conventional oral dosage forms transit quickly. In contrast, the Acuform technology is designed to be retained in the stomach, allowing for constant multi-hour flow of drugs to these regions of the gastrointestinal tract. Accordingly, for such drugs, we believe that the Acuform technology offers a significantly enhanced opportunity for increased absorption. Unlike some insoluble drug delivery systems, the polymer comprising the Acuform technology dissolves at the end of its useful life and is passed through the gastrointestinal tract and eliminated.



•

Rational Drug Combinations.  We believe that the Acuform technology may allow for rational combinations of drugs with different biological half-lives. Physicians frequently prescribe multiple drugs for treatment of a single medical condition. Single product combinations have not been considered feasible because the different biological half-lives of these combination drugs would result in an overdosage of one drug and/or an underdosage of the other. By appropriately incorporating different drugs into an Acuform technology we believe that we can provide for the release of each incorporated drug continuously at a rate and duration (dose) appropriately adjusted for the specific biological half-lives of the drugs. We believe that future rational drug combination products using the Acuform technology have the potential to simplify drug administration, increase patient compliance, and reduce medical costs.

COMPETITION

        Gralise for Postherpetic Neuralgia.    Gabapentin is currently marketed by Pfizer as Neurontin and by several generic manufacturers for adjunctive therapy for epileptic seizures and for postherpetic pain. In addition, Pfizer's product, Lyrica™ (pregabalin), has been approved for marketing in the United States and the European Union for the management of postherpetic neuralgia, diabetic neuropathy, partial seizures and fibromyalgia.

        Gralise will compete against other neuropathic pain treatments, such as anti-depressants, other anti-convulsants, local anesthetics used as regional nerve blockers, anti-arrythmics and opiods.

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        Glumetza.    Glumetza competes against immediate release metformin, which is marketed primarily by generic manufacturers. Glumetza also competes against both branded and generic extended release versions of metformin, such as Bristol-Myers Squibb's Glucophage XR and Shinogi's Fortamet. Generic extended release metformin manufacturers include Barr Pharmaceuticals, Inc., ANDRX Corporation, Mylan Laboratories, Inc., Watson Pharmaceuticals, Inc. and Teva Pharmaceutical Industries, Ltd., among others.

        Glumetza also competes against oral type 2 diabetes medications other than metformin, such as Takeda's Actos (pioglitazone hydrochloride), GlaxoSmithKline's Avandia (risiglitazon), Pfizer's Glucotrol (sulfonylurea) and Merck's Januvia (sitagliptin), among others.

        Serada for Menopausal Hot Flashes.    If approved, Serada for hot flashes will compete against HRT, such as Pfizer's Premarin (estrogens) and Prempro (a combination of estrogens and a progestin) products, and anti-depressant medications prescribed off-label. Wyeth's anti-depressant drug candidate, Pristiq, is in pre-registration for treatment of hot flashes. We are aware that Pfizer has non-exclusively licensed from the University of Rochester rights to develop a hot flash product containing pregabalin under the same patent we have sublicensed exclusive rights to develop a menopausal hot flash product containing gabapentin. Accordingly, Pfizer may develop a competing hot flash product.

        DM-1992 for Parkinson's Disease.    If approved, DM-1992 will compete against Sinemet, a combination of levodopa and carbidopa product for treatment of Parkinson's disease and syndrome sold by Merck as well as generic Sinemet sold by various generic manufacturers.

        Drug Delivery Technologies.    Other companies that have oral drug delivery technologies competitive with the Acuform technology include Elan Corporation, Bristol-Myers Squibb, Teva Pharmaceutical Industries, Ltd , Johnson & Johnson, SkyePharma plc, Valeant, Flamel Technologies S.A., Ranbaxy Laboratories, Ltd., and Intec Pharma, all of which develop oral tablet products designed to release the incorporated drugs over time. Each of these companies has patented technologies with attributes different from ours, and in some cases with different sites of delivery to the gastrointestinal tract.

        General.    We believe that we compete favorably in the markets described above on the basis of the safety and efficacy of our products and product candidates, and in some cases on the basis of the price of our products. However, competition in pharmaceutical products and drug delivery technologies is intense, and we expect competition to increase. There may be other companies developing products competitive with ours of which we are unaware. Competing product or technologies developed in the future may prove superior to our products or technologies, either generally or in particular market segments. These developments could make our products or technologies noncompetitive or obsolete.

        Most of our principal competitors have substantially greater financial, sales, marketing, personnel and research and development resources than we do. In addition, many of our potential collaborative partners have devoted, and continue to devote, significant resources to the development of their own products and drug delivery technologies.

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PATENTS AND PROPRIETARY RIGHTS

        Our material issued United States patents and the products and product candidates they cover are as follows:

        Our success will depend in part on our ability to obtain and maintain patent protection for our technologies and to preserve our trade secrets. Our policy is to seek to protect our proprietary rights, by among other methods, filing patent applications in the United States and foreign jurisdictions to cover certain aspects of our technology. In addition to those patents noted on the above table, we have 23 patent applications pending in the United States. We have also prepared and continue to prepare patent applications relating to our expanding technology for filing in the United States and abroad. We have also applied for patents in numerous foreign countries. Some of those countries have granted our applications and other applications are still pending. Our pending patent applications may lack priority over others' applications or may not result in the issuance of patents. Even if issued, our patents may not be sufficiently broad to provide protection against competitors with similar technologies and may be challenged, invalidated or circumvented, which could limit our ability to stop competitors from marketing related products or may not provide us with competitive advantages against competing products. We also rely on trade secrets and proprietary know-how, which are difficult to protect. We seek to protect such information, in part, through entering into confidentiality agreements with employees, consultants, collaborative partners and others before such persons or entities have access to our proprietary trade secrets and know-how. These confidentiality agreements may not be effective in certain cases, due to, among other things, the lack of an adequate remedy for breach of an agreement

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or a finding that an agreement is unenforceable. In addition, our trade secrets may otherwise become known or be independently developed by competitors.

        Our ability to develop our technologies and to make commercial sales of products using our technologies also depends on not infringing others' patents or other intellectual property rights. We are not aware of any intellectual property claims against us. However, the pharmaceutical industry has experienced extensive litigation regarding patents and other intellectual property rights. For example, Pfizer has initiated several suits against companies marketing generic gabapentin products, claiming that these products infringe Pfizer's patents. The results of this litigation could adversely impact the commercialization of pharmaceutical products that contain gabapentin as an active pharmaceutical ingredient. Also, we are aware that patents issued to third parties relating to extended release drug formulations or particular pharmaceutical compounds could in the future be asserted against us, although we believe that we do not infringe any valid claim of any patents. If claims concerning any of our products were to arise and it was determined that these products infringe a third party's proprietary rights, we could be subject to substantial damages for past infringement or be forced to stop or delay our activities with respect to any infringing product, unless we can obtain a license, or we may have to redesign our product so that it does not infringe upon others' patent rights, which may not be possible or could require substantial funds or time. Such a license may not be available on acceptable terms, or at all. Even if we, our collaborators or our licensors were able to obtain a license, the rights may be nonexclusive, which would give our competitors access to the same intellectual property. In addition, any public announcements related to litigation or interference proceedings initiated or threatened against us, even if such claims are without merit, could cause our stock price to decline.

        From time to time, we may become aware of activities by third parties that may infringe our patents. Infringement by others of our patents may reduce our market shares (if a related product is approved) and, consequently, our potential future revenues and adversely affect our patent rights if we do not take appropriate enforcement action. We may need to engage in litigation in the future to enforce any patents issued or licensed to us or to determine the scope and validity of third-party proprietary rights. Our issued or licensed patents may not be held valid by a court of competent jurisdiction. Whether or not the outcome of litigation is favorable to us, defending a lawsuit takes significant time, may be expensive and may divert management attention from other business concerns. We may also be required to participate in interference proceedings declared by the United States Patent and Trademark Office for the purpose of determining the priority of inventions in connection with our patent applications or other parties' patent applications. Adverse determinations in litigation or interference proceedings could require us to seek licenses which may not be available on commercially reasonable terms, or at all, or subject us to significant liabilities to third parties. If we need but cannot obtain a license, we may be prevented from marketing the affected product.

MANUFACTURING

        We have established internal manufacturing facilities that are in compliance with current good manufacturing practices, to manufacture supplies for our clinical trials.

        We are responsible for the supply and distribution of Glumetza, and we have entered into a manufacturing agreement with Patheon Puerto Rico Inc., as our sole supplier for tablets of the 500mg strength of Glumetza. We have two qualified suppliers for the active pharmaceutical ingredient in Glumetza and have a long-term supply agreement with one of the suppliers, Farmhispania, S.A. We have a supply agreement with Valeant, our sole supplier for the 1000mg formulation of Glumetza.

        We have obtained clinical and validation batches of Gralise and Serada from Patheon Puerto Rico Inc., our third-party manufacturer and sole supplier of Gralise and Serada product. We currently have no long-term supply arrangements for Gralise and Serada and obtain product on a purchase order

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basis. We have two qualified suppliers for the active pharmaceutical ingredient in Gralise and Serada. However, we obtain the active pharmaceutical ingredient on a purchase order basis only.

        We also obtain polyethylene oxide, one of the excipients common to Glumetza, Gralise and Serada, on a purchase order basis from Dow Chemical, a sole source for polyethylene oxide. We currently have no long-term supply arrangement with respect to polyethylene oxide.

        Applicable current Good Manufacturing Practices (cGMP) requirements and other rules and regulations prescribed by foreign regulatory authorities will apply to the manufacture of products using the Acuform technology. We will depend on the manufacturers of products using the Acuform technology to comply with cGMP and applicable foreign standards. Any failure by a manufacturer of products using the Acuform technology to maintain cGMP or comply with applicable foreign standards could delay or prevent the initial or continued commercial sale of our products.

MARKETING AND SALES

        In 2004, we announced our determination to evolve from a solely product development focused company to an integrated specialty pharmaceutical company, with sales and marketing of our own products. Preliminary staffing for these activities began in 2005. From 2006 through 2010, we enhanced our internal sales and marketing capabilities through the hiring of additional sales and marketing employees and the engagement of consultants. We anticipate the build-up of our commercial infrastructure will continue over the next several years.

        In 2007 and 2008, our commercial organization transitioned to us the Glumetza marketing efforts previously undertaken by King and directed the efforts of a temporary contract sales organization. In July 2008, we entered into a promotion agreement with Santarus for Glumetza, and our commercial organization has transitioned the promotion and marketing efforts for Glumetza to Santarus, who began promotion in October 2008.

        We have developed capabilities in various aspects of pharmaceutical sales and marketing through our commercialization of Glumetza and Proquin XR, including manufacturing, quality assurance, wholesale distribution, medical affairs, managed market contracting, government price reporting, maintenance of the product NDA and review and submission of promotional materials.

        Our sales and marketing personnel are also engaged in preparation for the commercialization and launch of Gralise, the commercial and marketing assessments of Serada and other potential product candidates.

        All marketing activities associated with Gralise and Glumetza, as well as marketing activities related to any other products for which we obtain regulatory approval, will be subject to numerous federal and state laws governing the marketing and promotion of pharmaceutical products. The FDA regulates post-approval promotional labeling and advertising to ensure that they conform with statutory and regulatory requirements. In addition to FDA restrictions, the marketing of prescription drugs is subject to laws and regulations prohibiting fraud and abuse under government healthcare programs. For example, the federal healthcare program antikickback statute prohibits giving things of value to induce the prescribing or purchase of products that are reimbursed by federal healthcare programs, such as Medicare and Medicaid. In addition, federal false claims laws prohibit any person from knowingly presenting, or causing to be presented, a false claim for payment to the federal government. Under this law, the federal government in recent years has brought claims against drug manufacturers alleging that certain marketing activities caused false claims for prescription drugs to be submitted to federal programs. Many states have similar statutes or regulations, which apply to items and services reimbursed under Medicaid and other state programs, or, in some states, regardless of the payer. If we, or our collaborative partners, fail to comply with applicable FDA regulations or other laws or regulations relating to the marketing of our products, we could be subject to criminal prosecution, civil

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penalties, seizure of products, injunction, exclusion of our products from reimbursement under government programs, as well as other regulatory actions against our product candidates, our collaborative partners or us.

GOVERNMENT REGULATION

        Numerous governmental authorities in the United States and other countries regulate our research and development activities and those of our collaborative partners. Governmental approval is required of all potential pharmaceutical products using the Acuform technology and the manufacture and marketing of products using the Acuform technology prior to the commercial use of those products. The regulatory process takes several years and requires substantial funds. If new products using the Acuform technology do not receive the required regulatory approvals or if such approvals are delayed, our business would be materially adversely affected. There can be no assurance that the requisite regulatory approvals will be obtained without lengthy delays, if at all.

        In the United States, the FDA rigorously regulates pharmaceutical products, including any drugs using the Acuform technology. If a company fails to comply with applicable requirements, the FDA or the courts may impose sanctions. These sanctions may include civil penalties, criminal prosecution of the company or its officers and employees, injunctions, product seizure or detention, product recalls and total or partial suspension of production. The FDA may withdraw approved applications or refuse to approve pending new drug applications, premarket approval applications, or supplements to approved applications.

        We may be required to conduct preclinical testing on laboratory animals of new pharmaceutical products prior to commencement of clinical studies involving human beings. These studies evaluate the potential efficacy and safety of the product. If preclinical testing is required, we must submit the results of the studies to the FDA as part of an Investigational New Drug Application, which must become effective before beginning clinical testing in humans.

        The products we develop generally are or will be submitted for approval under Section 505(b)(2) of the FDCA which was enacted as part of the Drug Price Competition and Patent Term Restoration Act of 1984, otherwise known as the Hatch-Waxman Act. Section 505(b)(2) permits the submission of an NDA where at least some of the information required for approval comes from studies not conducted by or for the applicant and for which the applicant has not obtained a right of reference. For instance, the NDA for Gralise relies on the FDA's prior approval of Neurontin® (gabapentin), the immediate release formulation of gabapentin initially approved by the FDA. An NDA for Serada would also rely in part on the FDA's prior approval of Neurontin®.

        Typically, human clinical evaluation involves a time-consuming and costly three-phase process:

•

In Phase 1, we conduct clinical trials with a small number of subjects to determine a drug's early safety profile and its pharmacokinetic pattern.



•

In Phase 2, we conduct limited clinical trials with groups of patients afflicted with a specific disease in order to determine preliminary efficacy, optimal dosages and further evidence of safety.



•

In Phase 3, we conduct large-scale, multi-center, comparative trials with patients afflicted with a target disease in order to provide enough data to statistically evaluate the efficacy and safety of the product candidate, as required by the FDA.

        The FDA closely monitors the progress of each phase of clinical testing. The FDA may, at its discretion, re-evaluate, alter, suspend or terminate testing based upon the data accumulated to that point and the FDA's assessment of the risk/benefit ratio to patients. The FDA may also require additional clinical trials after approval, which are known as Phase 4 trials.

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        The results of preclinical and clinical testing are submitted to the FDA in the form of an NDA, for approval prior to commercialization. An NDA requires that our products are compliant with cGMP. Failure to achieve or maintain cGMP standards for products using the Acuform technology would adversely impact their marketability. In responding to an NDA, the FDA may grant marketing approval, request additional information or deny the application. Failure to receive approval for any products using the Acuform technology would have a material adverse effect on the Company.

        The FDA regulates not only prescription and over-the-counter drugs approved by NDAs, but also over-the-counter products that comply with monographs issued by the FDA. These regulations include:

•

cGMP requirements;



•

general and specific over-the-counter labeling requirements (including warning statements);



•

advertising restrictions; and



•

requirements regarding the safety and suitability of inactive ingredients.

        In addition, the FDA may inspect over-the-counter products and manufacturing facilities. A failure to comply with applicable regulatory requirements may lead to administrative or judicially imposed penalties. If an over-the-counter product differs from the terms of a monograph, it will, in most cases, require FDA approval of an NDA for the product to be marketed.

        Foreign regulatory approval of a product must also be obtained prior to marketing the product internationally. Foreign approval procedures vary from country to country. The time required for approval may delay or prevent marketing in certain countries. In certain instances we or our collaborative partners may seek approval to market and sell certain products outside of the United States before submitting an application for United States approval to the FDA. The clinical testing requirements and the time required to obtain foreign regulatory approvals may differ from that required for FDA approval. Although there is now a centralized European Union (EU) approval mechanism in place, each EU country may nonetheless impose its own procedures and requirements. Many of these procedures and requirements are time-consuming and expensive. Some EU countries require price approval as part of the regulatory process. These constraints can cause substantial delays in obtaining required approval from both the FDA and foreign regulatory authorities after the relevant applications are filed, and approval in any single country may not meaningfully indicate that another country will approve the product.

EMPLOYEES

        As of March 4, 2011, we had 69 full-time employees. At December 31, 2010, we had 70 full-time employees. None of our employees are represented by a collective bargaining agreement, nor have we experienced any work stoppage. We believe that our relations with our employees are good.

ITEM 1A.    RISK FACTORS

        In addition to other information in this report, the following factors should be considered carefully in evaluating an investment in our securities. If any of the risks or uncertainties described in this Form 10-K actually occurs, our business, results of operations or financial condition could be materially adversely affected. The risks and uncertainties described in this Form 10-K are not the only ones facing us. Additional risks and uncertainties of which we are unaware or currently deem immaterial may also become important factors that may harm our business.

We may not successfully commercialize Gralise, which would harm our business.

        Although Gralise has been approved for marketing, our ability to generate significant revenue from Gralise requires that we successfully commercialize the product on our own or with the assistance

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of a collaborative co-promotion or licensing partner. We retained marketing rights to Gralise in March 2011 in connection with the termination of our Gralise exclusive license agreement with Abbott Products, and we do not currently have a collaborative partner to assist us with the commercialization of Gralise. We are a small organization with limited experience selling and marketing pharmaceutical products, and have had little time to build capabilities necessary to commercialize the product. We may not be able to adequately build or maintain the necessary sales, marketing, managed markets or other capabilities on our own required to successfully commercialize Gralise, and we may not enter into arrangements with a collaborative partner or other third parties to perform those functions for us. Also, the establishment and maintenance of those capabilities may require us to divert capital from other intended purposes.

        Given the small size of our company and the experience and expertise of our current staff, effectively managing a significant number of collaborative partners and third-party contractors may be challenging. If our management of collaborative partners and third-party contractors is not effective, the commercial acceptance and success of Gralise may be delayed or limited.

        If we enter into a collaborative co-promotion or licensing arrangement related to Gralise, some or all of the revenues we receive will depend upon the efforts of one or more third parties, which may not be successful.

We may not be able to obtain orphan drug exclusivity for Gralise in PHN.

        The FDA has granted Gralise Orphan Drug designation for the management of PHN based on the size of the PHN population and the reduced incidence of adverse events observed in Gralise clinical trials relative to the incidence of adverse events reported in the package insert for immediate release gabapentin. Subsequent to the FDA's approval of Gralise, we were informed additional submissions or evidence to demonstrate the clinical superiority of Gralise based on improved safety will be required to be provided to the FDA in order to obtain a seven-year period of orphan exclusivity in PHN. If we obtain the orphan exclusivity, the FDA may not approve another application to market the same drug for the same indication until January 2018, except in very limited circumstances.

        If we do not obtain orphan exclusivity for Gralise, the period of market exclusivity in the United States for Gralise may be reduced, which would adversely affect our revenues.

If generic manufacturers use litigation and regulatory means to obtain approval for generic versions of our products, our business will suffer.

        Under the Federal Food, Drug and Cosmetics Act (FDCA), the FDA can approve an Abbreviated New Drug Application (ANDA), for a generic version of a branded drug without undertaking the clinical testing necessary to obtain approval to market a new drug. In place of such clinical studies, an ANDA applicant usually needs only to submit data demonstrating that its product has the same active ingredient(s) and is bioequivalent to the branded product, in addition to any data necessary to establish that any difference in strength, dosage form, inactive ingredients, or delivery mechanism does not result in different safety or efficacy profiles, as compared to the reference drug.

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        The FDCA requires an applicant for a drug that relies, at least in part, on the patent of one of our branded drugs to notify us of their application and potential infringement of our patent rights. Upon receipt of this notice we have 45 days to bring a patent infringement suit in federal district court against the company seeking approval of a product covered by one of our patents. The discovery, trial and appeals process in such suits can take several years. If such a suit is commenced, the FDCA provides a 30-month stay on the FDA's approval of the competitor's application. Such litigation is often time-consuming and quite costly and may result in generic competition if such patent(s) are not upheld or if the generic competitor is found not to infringe such patent(s). If the litigation is resolved in favor of the applicant or the challenged patent expires during the 30-month stay period, the stay is lifted and the FDA may thereafter approve the application based on the standards for approval of ANDAs.

        In November 2009, we filed a lawsuit in the United States District Court for the Northern District of California against Lupin for infringement of U.S. Patent Nos. 6,340,475; 6,488,962; 6,635,280; and 6,723,340 listed in the Orange Book for Glumetza. The lawsuit is in response to an ANDA filed by Lupin with the FDA regarding Lupin's intent to market generic versions of the 500mg and 1000mg strengths of Glumetza prior to the expiration date of the asserted patents. We commenced the lawsuit against Lupin within the applicable 45 day period required to automatically stay, or bar, the FDA from approving Lupin's ANDA for 30 months or until a district court decision that is adverse to the asserted patents, whichever may occur earlier. The 30-month stay expires in May 2012. If the litigation is still ongoing after expiration of the applicable 30-month stay, the termination of the stay could result in the introduction of one or more products generic to Glumetza prior to resolution of the litigation.

        The filing of the Lupin ANDA described above, or any other ANDA in respect to any of our products could have an adverse impact on our stock price. Moreover, if the patents covering our products were not upheld in litigation or if a generic competitor is found not to infringe these patents, the resulting generic competition would have a material adverse effect on our business, results of operations, financial condition and cash flows.

Our prior clinical trials evaluating Serada for menopausal hot flashes failed to meet all of their primary endpoints and there can be no assurance this product will be approved for marketing.

        In October 2009, our Phase 3 trials evaluating Serada for menopausal hot flashes failed to meet all of their primary endpoints. In December 2009, we met and discussed with the FDA the results of the trials and any additional clinical development that may be required to complete the program and obtain regulatory approval to market Serada in the United States. We initiated an additional Phase 3 trial for Serada in August 2010, known as Breeze 3. There can be no assurance the results of the Breeze 3 trial will demonstrate the product candidate is sufficiently safe and effective to obtain approval for marketing.

        We will incur significant additional expenses and will not know for at least another 9 to 12 months whether a New Drug Application could be submitted to the FDA to be approved for marketing. Clinical development is a long, expensive and uncertain process and is subject to delays. Positive or encouraging results of prior clinical trial are not necessarily indicative of the results we will obtain in later clinical trials. Accordingly, our additional Phase 3 trial may not demonstrate that Serada is effective for menopausal hot flashes. In addition, data obtained from pivotal clinical trials are susceptible to varying interpretations, which could delay, limit or prevent regulatory approval.

        Many other factors could delay or result in termination of our clinical trials, including:

•

negative or inconclusive results;



•

patient noncompliance with the protocol;



•

adverse medical events or side effects among patients during the clinical trials;

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•

FDA inspections of our clinical operations; and



•

real or perceived lack of effectiveness or safety of the product candidate.

We depend heavily on Santarus, Inc. for the successful commercialization of Glumetza in the United States.

        In July 2008, we entered into a promotion agreement with Santarus, Inc. pursuant to which Santarus will promote Glumetza in the United States through its sales force beginning in the fourth quarter of 2008. Under the agreement, in exchange for promotion fees, Santarus is required to market and promote Glumetza to physicians in the United States, to deliver annual detail calls to potential Glumetza prescribers, and to maintain a sales force of a minimum size. Although we have retained rights to promote Glumetza to obstetricians/gynecologists, or ob/gyns, and to retain a significant portion of the revenues from incremental sales generated by ob/gyns we call upon, ob/gyns generally do not prescribe significant amounts of metformin products. In addition, we do not have any immediate plans to establish a sales force, or contract with a third party to act as our sales force, for the purpose of exercising our Glumetza co-promotion rights. Accordingly, the success of the commercialization of Glumetza will depend in large part on Santarus' marketing and promotion efforts. Other factors that may affect the success of our promotion arrangement with Santarus include the following:

•

Santarus may acquire or develop alternative products (as it did in the third quarter of 2010);



•

Santarus may pursue higher-priority programs, or change the focus of its marketing programs;



•

Santarus may in the future choose to devote fewer resources to Glumetza;



•

Glumetza may fail to achieve greater market acceptance;



•

The outcome of our ongoing litigation against Lupin Limited seeking to prevent Lupin from marketing a generic version of Glumetza in the United States;



•

Santarus may experience financial difficulties; and



•

Santarus may fail to comply with its obligations under our promotion agreement.

        In addition to the factors described above, Santarus' business and product revenue have been adversely affected by the introduction of a generic version of its Zegerid® (omeprazole/sodium bicarbonate) prescription products in the third quarter of 2010.

        Any of the preceding factors could affect Santarus' commitment to the collaboration, which, in turn, could adversely affect the commercial success of Glumetza. Any failure to successfully commercialize Glumetza could have a material adverse effect on our business, financial conditions, results of operations and cash flows.

We cannot be certain of the extent to which commercialization of Glumetza will continue to be negatively impacted by the recent recall of Glumetza.

        In June 2010, we initiated a voluntary, wholesaler-level recall of 500mg Glumetza product due to the presence of trace amounts of a chemical called 2,4,6-tribromoanisole, or TBA, in bottles containing 500mg Glumetza tablets. In connection with the recall, we temporarily suspended product shipments of the 500mg Glumetza. We resumed supply of the 500mg Glumetza in January 2011.

        The supply disruption of the 500mg Glumetza has adversely impacted our product revenue and profitability of Glumetza. In addition, other pharmaceutical companies have encountered complex TBA-related supply issues and the issues may be difficult to remediate. Many of the patients who were previously prescribed Glumetza may be taking other prescription metformin products, and we may not be able to ever regain the lost share of the business. We may also suffer damage to our reputation and face product liability claims.

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The development of drug candidates is inherently uncertain and we cannot be certain that any of our product candidates will be approved for marketing or, if approved, will achieve market acceptance.

        We have the following programs in clinical development: Serada for menopausal hot flashes and DM-1992 for Parkinson's. We also have other product candidates in earlier stages of development.

        Our own product candidates and those of our collaborative partners are subject to the risk that any or all of them may be found to be ineffective or unsafe, or otherwise may fail to receive necessary regulatory clearances. Additionally, clinical trial results in earlier trials may not be indicative of results that will be obtained in subsequent larger trials, as was the case with the Phase 3 trial for Gralise for the management of postherpetic neuralgia that we completed in 2007, and with the Phase 3 trials evaluating Serada for menopausal hot flashes we completed in October 2009.

        We are unable to predict whether any of these product candidates will receive regulatory clearances or be successfully manufactured or marketed. Further, due to the extended testing and regulatory review process required before marketing clearance can be obtained, the time frames for commercialization of any products are long and uncertain. Even if these other product candidates receive regulatory clearance, our products may not achieve or maintain market acceptance. Also, substantially all of our product candidates use the Acuform technology. If it is discovered that the Acuform technology could have adverse effects or other characteristics that indicate it is unlikely to be effective as a delivery system for drugs or therapeutics, our product development efforts and our business could be significantly harmed.

We may incur operating losses in the future.

        For the years ended December 31, 2010, 2009 and 2008, we recorded total revenues of $80.8 million, $57.7 million, and $34.8 million, respectively. Collaborative milestones received from Abbott Products, Janssen and Merck resulted in the Company reaching profitability in 2010. For the years ended December 31, 2009 and 2008, we incurred net losses of $22.0 million and $15.3 million, respectively. We may incur operating losses in future fiscal years. Any such losses may have an adverse impact on our total assets, shareholders' equity and working capital.

Our operating results may fluctuate and affect our stock price.

        The following factors will affect our operating results and may result in a material adverse effect on our stock price:

•

the timing of the launch and degree of commercial success of Gralise;



•

our efforts to secure a commercialization partner for Gralise;



•

announcements and results regarding clinical trial results and plans for our drug candidates, including Serada;



•

filings and other regulatory actions related to Serada and our other product candidates;



•

developments concerning proprietary rights, including patents, infringement allegations and litigation matters;



•

decisions by collaborative partners to proceed or not to proceed with subsequent phases of a collaboration or program;



•

the degree of commercial success of Glumetza;



•

adverse events related to our products, including recalls;



•

interruptions of manufacturing or supply, or other manufacture or supply difficulties;

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•

the outcome of our patent infringement litigation against Lupin for Glumetza;



•

variations in revenues obtained from collaborative agreements, including milestone payments, royalties, license fees and other contract revenues;



•

market acceptance of the Acuform technology;



•

adoption of new technologies by us or our competitors;



•

the introduction of new products by our competitors;



•

the status of our compliance with laws and regulations applicable to the commercialization of pharmaceutical products;



•

any limitations to access to physician prescription data, which may make our marketing efforts more effective;



•

manufacturing costs;



•

third-party reimbursement policies; and



•

the status of our compliance with the provisions of the Sarbanes-Oxley Act of 2002.

        As a result of these factors, our stock price may continue to be volatile and investors may be unable to sell their shares at a price equal to, or above, the price paid. Additionally, any significant drops in our stock price, such as the one we experienced following the announcement of our Serada Phase 3 trial results in October 2009, could give rise to shareholder lawsuits, which are costly and time consuming to defend against and which may adversely affect our ability to raise capital while the suits are pending, even if the suits are ultimately resolved in our favor.

Our collaborative arrangements may give rise to disputes over commercial terms, contract interpretation and ownership of our intellectual property and may adversely affect the commercial success of our products.

        We currently have collaboration or license arrangements with Santarus, Covidien, Merck, Janssen, Boehringer Ingelheim, and PharmaNova. In addition, we have in the past and may in the future enter into other collaborative arrangements, some of which have been based on less definitive agreements, such as memoranda of understanding, material transfer agreements, options or feasibility agreements. We may not execute definitive agreements formalizing these arrangements.

        Collaborative relationships are generally complex and may give rise to disputes regarding the relative rights, obligations and revenues of the parties, including the ownership of intellectual property and associated rights and obligations, especially when the applicable collaborative provisions have not been fully negotiated and documented. Such disputes can delay collaborative research, development or commercialization of potential products, and can lead to lengthy, expensive litigation or arbitration. The terms of collaborative arrangements may also limit or preclude us from developing products or technologies developed pursuant to such collaborations. Additionally, the collaborators under these arrangements might breach the terms of their respective agreements or fail to prevent infringement of the licensed patents by third parties. Moreover, negotiating collaborative arrangements often takes considerably longer to conclude than the parties initially anticipate, which could cause us to enter into less favorable agreement terms that delay or defer recovery of our development costs and reduce the funding available to support key programs.

        We may be unable to enter into future collaborative arrangements on acceptable terms, which could harm our ability to develop and commercialize our current and potential future products. Further, even if we do enter into collaboration arrangements, it is possible that our collaborative partners may not choose to develop and commercialize products using the Acuform technology. Other

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factors relating to collaborations that may adversely affect the commercial success of our products include:

•

any parallel development by a collaborative partner of competitive technologies or products;



•

arrangements with collaborative partners that limit or preclude us from developing products or technologies;



•

premature termination of a collaboration agreement; or



•

Failure by a collaborative partner to devote sufficient resources to the development and commercial sales of products using the Acuform technology.

        Our collaborative arrangements do not necessarily restrict our collaborative partners from competing with us or restrict their ability to market or sell competitive products. Our current and any future collaborative partners may pursue existing or other development-stage products or alternative technologies in preference to those being developed in collaboration with us. Our collaborative partners may also terminate their collaborative relationships with us or otherwise decide not to proceed with development and commercialization of our products.

Our credit facility contains operating covenants that may restrict our business and financing activities.

        We entered into a $15.0 million credit facility with Oxford Finance Corporation and General Electric Capital Corporation in June 2008. We have drawn $9.4 million under the facility and will not make any further draws under the facility. As of December 31, 2010, we have $2.2 million of principal outstanding under the facility. The credit facility is secured by a pledge of all of our assets other than intellectual property, and contains a variety of operational covenants, including limitations on our ability to incur liens or additional debt, make dispositions, pay dividends, redeem our stock, make certain investments and engage in certain merger, consolidation or asset sale transactions and transactions with affiliates, among other restrictions. Any future debt financing we enter into may involve similar or more restrictive covenants affecting our operations. Our borrowings under the credit facility or any future debt financing will need to be repaid, which creates additional financial risk for our company, particularly if our business, or prevailing financial market conditions, are not conducive to paying off or refinancing our outstanding debt obligations. Furthermore, our failure to comply with the covenants in the credit facility could result in an event of default that, if not cured or waived, could result in the acceleration of all or a substantial portion of our debt, which could have a material adverse effect on our cash position and significantly harm our business.

Our existing resources may not be sufficient to fund our operations until such time as we may be able to consistently generate sufficient revenues to support our operations.

        Our existing capital resources may not be sufficient to fund our operations until such time as we may be able to generate sufficient revenues to consistently support our operations. We currently have no other committed sources of capital. To the extent that our capital resources are insufficient to meet our future capital requirements, in order to continue our development programs, we will have to raise additional funds through the sale of our equity securities, through debt financing, or from development and licensing arrangements. We may be unable to raise such additional capital on favorable terms, or at all. If we raise additional capital by selling our equity or convertible debt securities, the issuance of such securities could result in dilution of our shareholders' equity positions. If adequate funds are not available we may have to:

•

delay, postpone or terminate clinical trials;



•

significantly curtail commercialization of our marketed products or other operations; and/or



•

obtain funds through entering into collaboration agreements on unattractive terms.

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We may be unable to protect our intellectual property and may be liable for infringing the intellectual property of others.

        Our success will depend in part on our ability to obtain and maintain patent protection for our products and technologies, and to preserve our trade secrets. Our policy is to seek to protect our proprietary rights, by, among other methods, filing patent applications in the United States and foreign jurisdictions to cover certain aspects of our technology. We hold issued United States patents, and have patent applications pending in the United States. In addition, we are preparing patent applications relating to our expanding technology for filing in the United States and abroad. We have also applied for patents in numerous foreign countries. Some of those countries have granted our applications and other applications are still pending. Our pending patent applications may lack priority over others' applications or may not result in the issuance of patents. Even if issued, our patents may not be sufficiently broad to provide protection against competitors with similar technologies and may be challenged, invalidated or circumvented, which could limit our ability to stop competitors from marketing related products or may not provide us with competitive advantages against competing products. We also rely on trade secrets and proprietary know-how, which are difficult to protect. We seek to protect such information, in part, through entering into confidentiality agreements with employees, consultants, collaborative partners and others before such persons or entities have access to our proprietary trade secrets and know-how. These confidentiality agreements may not be effective in certain cases, due to, among other things, the lack of an adequate remedy for breach of an agreement or a finding that an agreement is unenforceable. In addition, our trade secrets may otherwise become known or be independently developed by competitors.

        Our ability to develop our technologies and to make commercial sales of products using our technologies also depends on not infringing others' patents or other intellectual property rights. We are not aware of any intellectual property claims against us. However, the pharmaceutical industry has experienced extensive litigation regarding patents and other intellectual property rights. For example, Pfizer has initiated several suits against companies marketing generic gabapentin products, claiming that these products infringe Pfizer's patents. The results of this litigation could adversely impact the commercialization of pharmaceutical products that contain gabapentin as an active pharmaceutical ingredient. Also, patents issued to third parties relating to sustained release drug formulations or particular pharmaceutical compounds could in the future be asserted against us, although we believe that we do not infringe any valid claim of any patents. If claims concerning any of our products were to arise and it was determined that these products infringe a third party's proprietary rights, we could be subject to substantial damages for past infringement or be forced to stop or delay our activities with respect to any infringing product, unless we can obtain a license, or we may have to redesign our product so that it does not infringe upon others' patent rights, which may not be possible or could require substantial funds or time. Such a license may not be available on acceptable terms, or at all. Even if we, our collaborators or our licensors were able to obtain a license, the rights may be nonexclusive, which could give our competitors access to the same intellectual property. In addition, any public announcements related to litigation or interference proceedings initiated or threatened against us, even if such claims are without merit, could cause our stock price to decline.

        From time to time, we may become aware of activities by third parties that may infringe our patents. Infringement by others of our patents may reduce our market shares (if a related product is approved) and, consequently, our potential future revenues and adversely affect our patent rights if we do not take appropriate enforcement action. We may need to engage in litigation in the future to enforce any patents issued or licensed to us or to determine the scope and validity of third-party proprietary rights. Our issued or licensed patents may not be held valid by a court of competent jurisdiction. Whether or not the outcome of litigation is favorable to us, defending a lawsuit takes significant time, may be expensive and may divert management attention from other business concerns. We may also be required to participate in interference proceedings declared by the United States

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Patent and Trademark Office for the purpose of determining the priority of inventions in connection with our patent applications or other parties' patent applications. Adverse determinations in litigation or interference proceedings could require us to seek licenses which may not be available on commercially reasonable terms, or at all, or subject us to significant liabilities to third parties. If we need but cannot obtain a license, we may be prevented from marketing the affected product.

Our licensed patent covering the use of gabapentin to treat hot flashes associated with menopause is a method-of-use patent, which increases the risk that prescriptions for gabapentin to treat hot flashes in menopausal women could be written for, or filled with, generic gabapentin.

        We have an exclusive sublicense from PharmaNova, Inc. to a patent held by the University of Rochester to develop and commercialize in the United States a gabapentin product for the treatment of hot flashes associated with menopause. Because a method-of-use patent, such as the patent we have sublicensed from PharmaNova, covers only a specified use of a particular compound, not a particular composition of matter, we cannot prevent others from commercializing gabapentin. Accordingly, physicians could prescribe another manufacturer's gabapentin to treat hot flashes in menopausal women rather than Serada, or pharmacists could seek to fill prescriptions for Serada with another manufacturer's gabapentin. Although any such "off-label" use could violate our licensed patent, effectively monitoring compliance with our licensed patent may be difficult and costly.

It is difficult to develop a successful product. If we do not continue to develop successful products, our financial position and liquidity will be adversely affected.

        The drug development process is costly, time-consuming and subject to unpredictable delays and failures. Before we or others make commercial sales of products using the Acuform technology, other than Gralise and Glumetza, we, our current and any future collaborative partners will need to:

•

conduct preclinical and clinical tests showing that these products are safe and effective; and



•

obtain regulatory approval from the FDA or foreign regulatory authorities.

        We will have to curtail, redirect or eliminate our product development programs if we or our collaborative partners find that:

•

the Acuform technology has unintended or undesirable side effects; or



•

product candidates that appear promising in preclinical or early-stage clinical studies do not demonstrate efficacy in later-stage, larger scale clinical trials.

        Even when or if our products obtain regulatory approval, successful commercialization requires:

•

market acceptance;



•

cost-effective commercial scale production; and



•

reimbursement under private or governmental health plans.

        Any material delay or failure in the governmental approval process and/or the successful commercialization of our potential products could adversely impact our financial position and liquidity.

If we do not achieve our projected development and commercialization goals in the timeframes we announce and expect, the commercialization of our product candidates may be delayed and our business will be harmed and our stock price may decline.

        For planning purposes, we sometimes estimate the timing of the accomplishment of various scientific, clinical, regulatory and other product development and commercialization goals. These milestones may include our expectations regarding the commercial launch of our products by us or our

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licensees, and the commencement or completion of scientific studies and clinical trials and the submission or approval of regulatory filings. From time to time, we may publicly announce the expected timing of some of these milestones, such as the completion of an ongoing clinical trial, the initiation of other clinical programs, or the commercial launch of products. All of these milestones are based on a variety of assumptions. The actual timing of these milestones can vary considerably from our estimates depending on numerous factors, some of which are beyond our control, including:

•

the efforts of our marketing partners with respect to the commercialization of our products;



•

the rate of progress, costs and results of our clinical trial and research and development activities, including the extent of scheduling conflicts with participating clinicians and clinical institutions and our ability to identify and enroll patients who meet clinical trial eligibility criteria;



•

our receipt of approvals by the FDA and other regulatory agencies and the timing thereof;



•

other actions by regulators;



•

our ability to access sufficient, reliable and affordable supplies of components used in the manufacture of our product candidates, including materials for our Acuform technology;



•

our available capital resources; and



•

the costs of ramping up and maintaining manufacturing operations, as necessary.

        If we fail to achieve our announced milestones in the timeframes we announce and expect, our business and results of operations may be harmed and the price of our stock may decline.

We depend on clinical investigators and clinical sites to enroll patients in our clinical trials and other third parties to manage the trials and to perform related data collection and analysis, and, as a result, we may face costs and delays outside of our control.

        We rely on clinical investigators and clinical sites to enroll patients and other third parties to manage our trials and to perform related data collection and analysis. However, we may be unable to control the amount and timing of resources that the clinical sites that conduct the clinical testing may devote to our clinical trials. If our clinical investigators and clinical sites fail to enroll a sufficient number of patients in our clinical trials or fail to enroll them on our planned schedule, we will be unable to complete these trials or to complete them as planned, which could delay or prevent us from obtaining regulatory approvals for our product candidates.

        Our agreements with clinical investigators and clinical sites for clinical testing and for trial management services place substantial responsibilities on these parties, which could result in delays in, or termination of, our clinical trials if these parties fail to perform as expected. For example, if any of our clinical trial sites fail to comply with FDA-approved good clinical practices, we may be unable to use the data gathered at those sites. If these clinical investigators, clinical sites or other third parties do not carry out their contractual duties or obligations or fail to meet expected deadlines, or if the quality or accuracy of the clinical data they obtain is compromised due to their failure to adhere to our clinical protocols or for other reasons, our clinical trials may be extended, delayed or terminated, and we may be unable to obtain regulatory approval for, or successfully commercialize, our product candidates.

If we are unable to obtain or maintain regulatory approval, we will be limited in our ability to commercialize our products, and our business will be harmed.

        The regulatory process is expensive and time consuming. Even after investing significant time and expenditures on clinical trials, we may not obtain regulatory approval of our product candidates. Data obtained from clinical trials are susceptible to varying interpretations, which could delay, limit or

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prevent regulatory approval, and the FDA may not agree with our methods of clinical data analysis or our conclusions regarding safety and/or efficacy. Significant clinical trial delays could impair our ability to commercialize our products and could allow our competitors to bring products to market before we do. In addition, changes in regulatory policy for product approval during the period of product development and regulatory agency review of each submitted new application may cause delays or rejections. Even if we receive regulatory approval, this approval may entail limitations on the indicated uses for which we can market a product.

        For example, the active ingredients in the products utilizing our Acuform delivery technology that are being developed pursuant to our collaboration with Covidien include acetaminophen in combination with opiates. In connection with concerns that consumers may inadvertently take more than the recommended daily dose of acetaminophen, potentially causing liver damage, an FDA advisory committee has recommended that prescription products containing acetaminophen in combination with prescription analgesics (including opiates) should include black box warnings and/or be removed from the market. The FDA is evaluating the recommendations and has indicated that such an evaluation will take some time. The FDA is not required to accept advisory committee recommendations. Covidien's ability or willingness to develop and market the products subject to our collaboration may be adversely affected by actions of the FDA in response to the advisory committee recommendations.

        Further, with respect to our approved products, once regulatory approval is obtained, a marketed product and its manufacturer are subject to continual review. The discovery of previously unknown problems with a product or manufacturer may result in restrictions on the product, manufacturer or manufacturing facility, including withdrawal of the product from the market. Manufacturers of approved products are also subject to ongoing regulation and inspection, including compliance with FDA regulations governing current Good Manufacturing Practices (cGMP). The FDCA, the Controlled Substances Act and other federal and foreign statutes and regulations govern and influence the testing, manufacturing, packing, labeling, storing, record keeping, safety, approval, advertising, promotion, sale and distribution of our products. The failure to comply with these regulations can result in, among other things, warning letters, fines, injunctions, civil penalties, recall or seizure of products, total or partial suspension of production, non-renewal of marketing applications or criminal prosecution.

        We are also required to report adverse events associated with our products to the FDA and other regulatory authorities. Unexpected or serious health or safety concerns could result in labeling changes, recalls, market withdrawals or other regulatory actions. Recalls may be issued at our discretion or at the discretion of the FDA or other empowered regulatory agencies. For example, in June 2010, we instituted a voluntary class 2 recall of 52 lots of our 500mg Glumetza product after chemical traces of 2,4,6-tribromoanisole or TBA were found in the product bottle. We cannot be certain that the FDA will determine that we adequately addressed the matters that led to this recall or that the FDA will not seek to impose fines or sanctions against us as a result of this recall. Any such fines or sanctions could adversely affect our financial condition and results of operations.

We are subject to risks associated with NDAs submitted under Section 505(b)(2) of the Food, Drug and Cosmetic Act.

        The products we develop generally are or will be submitted for approval under Section 505(b)(2) of the FDCA which was enacted as part of the Drug Price Competition and Patent Term Restoration Act of 1984, otherwise known as the Hatch-Waxman Act. Section 505(b)(2) permits the submission of an NDA where at least some of the information required for approval comes from studies not conducted by or for the applicant and for which the applicant has not obtained a right of reference. For instance, the NDA for Gralise relies on the FDA's prior approval of Neurontin® (gabapentin), the immediate release formulation of gabapentin initially approved by the FDA. An NDA for Serada would also rely in part on the FDA's prior approval of Neurontin®.

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        For NDAs submitted under Section 505(b)(2) of the FDCA, the patent certification and related provisions of the Hatch-Waxman Act apply. In accordance with the Hatch-Waxman Act, such NDAs may be required to includes certifications, known as "Paragraph IV certifications," that certify any patents listed in the FDA's Orange Book publication in respect to any product referenced in the 505(b)(2) application, are invalid, unenforceable, and/or will not be infringed by the manufacture, use, or sale of the product that is the subject of the 505(b)(2) application. Under the Hatch-Waxman Act, the holder of the NDA which the 505(b)(2) application references may file a patent infringement lawsuit after receiving notice of the Paragraph IV certification. Filing of a patent infringement lawsuit triggers a one-time automatic 30-month stay of the FDA's ability to approve the 505(b)(2) application. Accordingly, we may invest a significant amount of time and expense in the development of one or more products only to be subject to significant delay and patent litigation before such products may be commercialized, if at all. A Section 505(b)(2) application may also not be approved until any non-patent exclusivity, such as exclusivity for obtaining approval of a new chemical entity, listed in the Orange Book for the referenced product has expired. The FDA may also require us to perform one or more additional clinical studies or measurements to support the change from the approved product. The FDA may then approve the new formulation for all or only some of the indications sought by us. The FDA may also reject our future Section 505(b)(2) submissions and require us to file such submissions under Section 501(b)(1) of the FDCA, which could be considerably more expensive and time consuming. These factors, among others, may limit our ability to successfully commercialize our product candidates.

Pharmaceutical marketing is subject to substantial regulation in the United States.

        All marketing activities associated with Gralise and Glumetza, as well as marketing activities related to any other products for which we obtain regulatory approval, will be subject to numerous federal and state laws governing the marketing and promotion of pharmaceutical products. The FDA regulates post-approval promotional labeling and advertising to ensure that they conform to statutory and regulatory requirements. In addition to FDA restrictions, the marketing of prescription drugs is subject to laws and regulations prohibiting fraud and abuse under government healthcare programs. For example, the federal healthcare program antikickback statute prohibits giving things of value to induce the prescribing or purchase of products that are reimbursed by federal healthcare programs, such as Medicare and Medicaid. In addition, federal false claims laws prohibit any person from knowingly presenting, or causing to be presented, a false claim for payment to the federal government. Under this law, the federal government in recent years has brought claims against drug manufacturers alleging that certain marketing activities caused false claims for prescription drugs to be submitted to federal programs. Many states have similar statutes or regulations, which apply to items and services reimbursed under Medicaid and other state programs, or, in some states, regardless of the payer. If we, or our collaborative partners, fail to comply with applicable FDA regulations or other laws or regulations relating to the marketing of our products, we could be subject to criminal prosecution, civil penalties, seizure of products, injunction, and exclusion of our products from reimbursement under government programs, as well as other regulatory actions against our product candidates, our collaborative partners or us.

We may incur significant liability if it is determined that we are promoting or have in the past promoted the "off-label" use of drugs.

        Companies may not promote drugs for "off-label" uses—that is, uses that are not described in the product's labeling and that differ from those approved by the FDA. Physicians may prescribe drug products for off-label uses, and such off-label uses are common across some medical specialties. Although the FDA and other regulatory agencies do not regulate a physician's choice of treatments, the FDCA and FDA regulations restrict communications on the subject of off-label uses of drug products by pharmaceutical companies. The Office of Inspector General of the Department of Health

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and Human Services (OIG), the FDA, and the Department of Justice (DOJ) all actively enforce laws and regulations prohibiting promotion of off-label uses and the promotion of products for which marketing clearance has not been obtained. A company that is found to have improperly promoted off-label uses may be subject to significant liability, including civil and administrative remedies as well as criminal sanctions.

        Notwithstanding the regulatory restrictions on off-label promotion, the OIG, the FDA, and DOJ allow companies to engage in truthful, non-misleading, and non-promotional speech concerning their products. If the OIG or the FDA takes the position that we are not in compliance with such requirements, and, if such non-compliance is proven, we may be subject to significant liability, including civil and administrative remedies, as well as criminal sanctions. In addition, management's attention could be diverted from our business operations and our reputation could be damaged.

The approval process outside the United States is uncertain and may limit our ability to develop, manufacture and sell our products internationally.

        To market any of our products outside of the United States, we and our collaborative partners, including Janssen, Merck, Boehringer Ingelheim and Madaus, are subject to numerous and varying foreign regulatory requirements, implemented by foreign health authorities, governing the design and conduct of human clinical trials and marketing approval for drug products. The approval procedure varies among countries and can involve additional testing, and the time required to obtain approval may differ from that required to obtain FDA approval. The foreign regulatory approval process includes all of the risks associated with obtaining FDA approval set forth above, and approval by the FDA does not ensure approval by the health authorities of any other country, nor does the approval by foreign health authorities ensure approval by the FDA.

If we or our marketing partners are unable to obtain acceptable prices or adequate reimbursement for our products from third-party payers, we will be unable to generate significant revenues.

        In both domestic and foreign markets, sales of our product candidates will depend in part on the availability of adequate reimbursement from third-party payers such as:

•

government health administration authorities;



•

private health insurers;



•

health maintenance organizations;



•

pharmacy benefit management companies; and



•

other healthcare-related organizations.

        If reimbursement is not available for our products or product candidates, demand for these products may be limited. Further, any delay in receiving approval for reimbursement from third-party payers could have an adverse effect on our future revenues. Third-party payers are increasingly challenging the price and cost-effectiveness of medical products and services. Significant uncertainty exists as to the reimbursement status of newly approved healthcare products, including pharmaceuticals. Our products may not be considered cost effective, and adequate third-party reimbursement may be unavailable to enable us to maintain price levels sufficient to realize an acceptable return on our investment.

        Federal and state governments in the United States and foreign governments continue to propose and pass new legislation designed to contain or reduce the cost of healthcare. Existing regulations affecting pricing may also change before many of our product candidates are approved for marketing. Cost control initiatives could decrease the price that we receive for any product we may develop.

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We may be unable to compete successfully in the pharmaceutical product and drug delivery technology industries.

        Other companies that have oral drug delivery technologies competitive with the Acuform technology include Elan Corporation, Bristol-Myers Squibb, TEVA Pharmaceutical Industries, Ltd., Johnson & Johnson, SkyePharma plc, Flamel Technologies S.A., Ranbaxy Laboratories, Ltd., and Intec Pharma, all of which develop oral tablet products designed to release the incorporated drugs over time. Each of these companies has patented technologies with attributes different from ours, and in some cases with different sites of delivery to the gastrointestinal tract.

        Bristol-Myers Squibb is currently marketing a sustained release formulation of metformin, Glucophage XR, with which Glumetza competes. The limited license that Bristol-Myers Squibb obtained from us under our November 2002 settlement agreement extends to certain current and internally-developed future compounds, which may increase the likelihood that we will face competition from Bristol-Myers Squibb in the future on products in addition to Glumetza. Several other companies, including Shinogi & Co., Ltd., Barr Pharmaceuticals, Inc., Mylan Laboratories, Inc. and Teva Pharmaceutical Industries, Ltd. have received FDA approval for and are selling a controlled-release metformin product.

        There may be other companies developing products competitive with Glumetza of which we are unaware.

        Gabapentin is currently marketed by Pfizer as Neurontin® for adjunctive therapy for epileptic seizures and for postherpetic pain. Pfizer's basic U.S. patents relating to Neurontin have expired, and numerous companies have received approval to market generic versions of the immediate release product. In addition, Pfizer has developed Lyrica® (pregabalin), which has been approved for marketing in the United States and the European Union.

        Competition in pharmaceutical products and drug delivery systems is intense. We expect competition to increase. Competing technologies or products developed in the future may prove superior to the Acuform technology or products using the Acuform technology, either generally or in particular market segments. These developments could make the Acuform technology or products using the Acuform technology noncompetitive or obsolete.

        Most of our principal competitors have substantially greater financial, sales, marketing, personnel and research and development resources than we do. In addition, many of our potential collaborative partners have devoted, and continue to devote, significant resources to the development of their own drug delivery systems and technologies.

We depend on third parties who are single source suppliers to manufacture Glumetza, Gralise and our other product candidates. If these suppliers are unable to manufacture Glumetza, Gralise or our product candidates, our business will be harmed.

        We are responsible for the supply and distribution of Glumetza, and Patheon is our sole supplier for tablets of the 500mg strength of Glumetza pursuant to a supply agreement we entered into with Patheon in December 2006. Valeant is our sole supplier for the 1000mg formulation Glumetza. We will be unable to manufacture Glumetza in a timely manner if we are unable to obtain 500mg Glumetza tablets from our contract manufacturer, active pharmaceutical ingredient from suppliers, or excipient suppliers, or 1000mg Glumetza tablets from Valeant.

        Patheon is also our sole supplier for Gralise and Serada tablets. We currently have no long-term supply arrangement with respect to Gralise or Serada. Any failure to obtain Gralise or Serada tablets from Patheon, active pharmaceutical ingredient from suppliers, or excipient suppliers, could adversely affect our operating results.

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        We do not have, and we do not intend to establish in the foreseeable future, internal commercial scale manufacturing capabilities. Rather, we intend to use the facilities of third parties to manufacture products for clinical trials and commercialization. Our dependence on third parties for the manufacture of products using the Acuform technology may adversely affect our ability to deliver such products on a timely or competitive basis. The manufacturing processes of our third party manufacturers may be found to violate the proprietary rights of others. If we are unable to contract for a sufficient supply of required products on acceptable terms, or if we encounter delays and difficulties in our relationships with manufacturers, the market introduction and commercial sales of our products will be delayed, and our future revenue will suffer.

A successful product liability claim against us could materially harm our business.

        Our business involves exposure to potential product liability risks that are inherent in the development and production of pharmaceutical products. We have obtained product liability insurance for clinical trials currently underway and forecasted 2011 sales of our products, but:

•

we may be unable to obtain product liability insurance for future trials;



•

we may be unable to obtain product liability insurance for future products;



•

we may be unable to maintain product liability insurance on acceptable terms;



•

we may be unable to secure increased coverage as the commercialization of the Acuform technology proceeds; or



•

our insurance may not provide adequate protection against potential liabilities.

        Our inability to obtain adequate insurance coverage at an acceptable cost could prevent or inhibit the commercialization of our products. Defending a lawsuit could be costly and significantly divert management's attention from conducting our business. If third parties were to bring a successful product liability claim or series of claims against us for uninsured liabilities or in excess of insured liability limits, our business, financial condition and results of operations could be materially harmed.

Our success is dependent in large part upon the continued services of our CEO and senior management with whom we do not have employment agreements.

        Our success is dependent in large part upon the continued services of our President and Chief Executive Officer, Carl A. Pelzel, and other members of our executive management team, and on our ability to attract and retain key management and operating personnel. We do not have agreements with Mr. Pelzel or any of our other executive officers that provide for their continued employment with us. We may have difficulty filling open senior scientific, financial and commercial positions. Management, scientific and operating personnel are in high demand in our industry and are often subject to competing offers. The loss of the services of one or more members of management or key employees or the inability to hire additional personnel as needed could result in delays in the research, development and commercialization of our products and potential product candidates.

If we choose to acquire new and complementary businesses, products or technologies, we may be unable to complete these acquisitions or to successfully integrate them in a cost effective and non-disruptive manner.

        Our success depends on our ability to continually enhance and broaden our product offerings in response to changing customer demands, competitive pressures and technologies. Accordingly, we may in the future pursue the acquisition of complementary businesses, products or technologies instead of developing them ourselves. We have no current commitments with respect to any acquisition or such investment. We do not know if we would be able to successfully complete any acquisitions, or whether we would be able to successfully integrate any acquired business, product or technology or retain any

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key employees. Integrating any business, product or technology we acquire could be expensive and time consuming, disrupt our ongoing business and distract our management. If we were to be unable to integrate any acquired businesses, products or technologies effectively, our business would suffer. In addition, any amortization or charges resulting from the costs of acquisitions could harm our operating results.

We have implemented certain anti-takeover provisions.

        Certain provisions of our articles of incorporation and the California General Corporation Law could discourage a third party from acquiring, or make it more difficult for a third party to acquire, control of our company without approval of our board of directors. These provisions could also limit the price that certain investors might be willing to pay in the future for shares of our common stock. Certain provisions allow the board of directors to authorize the issuance of preferred stock with rights superior to those of the common stock. We are also subject to the provisions of Section 1203 of the California General Corporation Law which requires a fairness opinion to be provided to our shareholders in connection with their consideration of any proposed "interested party" reorganization transaction.

        We have adopted a shareholder rights plan, commonly known as a "poison pill". The provisions described above, our poison pill and provisions of the California General Corporation Law may discourage, delay or prevent a third party from acquiring us.

Increased costs associated with corporate governance compliance may significantly impact our results of operations.

        Changing laws, regulations and standards relating to corporate governance, public disclosure and compliance practices, including the Sarbanes-Oxley Act of 2002, new SEC regulations and NASDAQ Global Market rules, are creating uncertainty for companies such as ours in understanding and complying with these laws, regulations and standards. As a result of this uncertainty and other factors, devoting the necessary resources to comply with evolving corporate governance and public disclosure standards has resulted in and may in the future result in increased general and administrative expenses and a diversion of management time and attention to compliance activities. We also expect these developments to increase our legal compliance and financial reporting costs. In addition, these developments may make it more difficult and more expensive for us to obtain director and officer liability insurance, and we may be required to accept reduced coverage or incur substantially higher costs to obtain coverage. Moreover, we may be unable to comply with these new rules and regulations on a timely basis.

        These developments could make it more difficult for us to attract and retain qualified members of our board of directors, or qualified executive officers. We are presently evaluating and monitoring regulatory developments and cannot estimate the timing or magnitude of additional costs we may incur as a result. To the extent these costs are significant, our selling, general and administrative expenses are likely to increase.

If we sell shares of our common stock in future financings, existing common shareholders will experience immediate dilution and, as a result, our stock price may go down.

        As capital raising opportunities present themselves, we may enter into financing arrangements in the future, including the issuance of debt securities, preferred stock or common stock. If we issue common stock or securities convertible into common stock, our common shareholders will experience dilution and this dilution will be greater if we find it necessary to sell securities at a discount to prevailing market prices.

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If we are unable to satisfy regulatory requirements relating to internal controls, our stock price could suffer.

        Section 404 of the Sarbanes-Oxley Act of 2002 requires companies to conduct a comprehensive evaluation of their internal control over financial reporting. At the end of each fiscal year, we must perform an evaluation of our internal control over financial reporting, include in our annual report the results of the evaluation, and have our external auditors publicly attest to such evaluation. If material weaknesses were found in our internal controls in the future, if we fail to complete future evaluations on time, or if our external auditors cannot attest to our future evaluations, we could fail to meet our regulatory reporting requirements and be subject to regulatory scrutiny and a loss of public confidence in our internal controls, which could have an adverse effect on our stock price.

Business interruptions could limit our ability to operate our business.

        Our operations are vulnerable to damage or interruption from computer viruses, human error, natural disasters, telecommunications failures, intentional acts of vandalism and similar events. In particular, our corporate headquarters are located in the San Francisco Bay area, which has a history of seismic activity. We have not established a formal disaster recovery plan, and our back-up operations and our business interruption insurance may not be adequate to compensate us for losses that occur. A significant business interruption could result in losses or damages incurred by us and require us to cease or curtail our operations.

ITEM 1B.    UNRESOLVED STAFF COMMENTS

        None.

ITEM 2.    PROPERTIES

        We currently lease approximately 55,000 square feet of laboratory and office facilities located at 1330, 1360 and 1430 O'Brien Drive, Menlo Park, California. The lease terms for each of these facilities are through January 31, 2012, and include options exercisable by the Company to further extend any of the lease terms for an additional five years. From March 2008 through June 2009, we subleased approximately 9,000 square feet of this space.

        We expect that these facilities will accommodate our growth for the next year.

ITEM 3.    LEGAL PROCEEDINGS

Depomed v. Lupin (U.S. Generic Glumetza Litigation)

        In November 2009, we filed a lawsuit in the United States District Court for the Northern District of California against Lupin Limited and its wholly-owned subsidiary, Lupin Pharmaceutical, Inc. (Lupin), for infringement of the patents listed in the Orange Book for Glumetza. The lawsuit is in response to an Abbreviated New Drug Application filed by Lupin with the FDA regarding Lupin's intent to market generic versions of 500mg and 1000mg dosage strengths of Glumetza prior to the expiration of the four listed patents (U.S. Patent Nos. 6,340,475; 6,488,962; 6,635,280; and 6,723,340). The Company commenced the lawsuit within the 45 days required to automatically stay, or bar, the FDA from approving Lupin's ANDA for 30 months or until a district court decision that is adverse to the patents, whichever may occur earlier. Absent a court decision, the 30-month stay is expected to expire in May 2012. Lupin has prepared and filed an answer in the case, principally asserting non-infringement and invalidity of the Orange Book patents, and has also filed counterclaims. Discovery is currently underway and a hearing for claim construction, or Markman hearing, was held in January 2011. An adverse outcome in this matter could substantially weaken our U.S. intellectual property.

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Valeant and Depomed v. Apotex (Canadian Generic Glumetza Litigation)

        In December 2007, Apotex, Inc. (Apotex) filed the Canadian equivalent of an Abbreviated New Drug Application in Canada seeking approval to market a generic version of the 500mg formulation of Glumetza in Canada.

        In February 2010, Apotex received clearance from the Minister of Health in Canada to market the generic version of the 500mg formulation of Glumetza. However, to date, Apotex has not launched a generic version of Glumetza in Canada.

        Also in February 2010, Valeant and Depomed filed a complaint in the Federal Court in Canada against Apotex for infringement of the Company's Canadian Patent No. 2,290,624.

        An adverse outcome in this matter could substantially weaken our Canadian intellectual property.

General

        We may from time to time become party to actions, claims, suits, investigations or proceedings arising from the ordinary course of our business, including actions with respect to intellectual property claims, breach of contract claims, labor and employment claims, and other matters. Although actions, claims, suits, investigations and proceedings are inherently uncertain and their results cannot be predicted with certainty, other than the matters set forth above, we are not currently involved in any matters that we believe may have a material adverse effect on our business, financial position, results of operations or cash flow. However, regardless of the outcome, litigation can have an adverse impact on us because of associated cost and diversion of management time.

ITEM 4.    RESERVED

EXECUTIVE AND OTHER OFFICERS OF THE REGISTRANT

        Our executive and other officers of the company and their ages as of March 11, 2011 are as follows:

        Carl A. Pelzel has served as President and Chief Executive Officer and as a member of the board of directors since August 2007. Mr. Pelzel joined Depomed in June 2005 as Vice President, Marketing and Commercial Development and was promoted to the position of Executive Vice President and Chief Operating Officer in September 2005. Before joining Depomed, Mr. Pelzel was Senior Vice President, Global Commercial Operations at Chiron Corporation from June 2003 to September 2004. Prior to joining Chiron, Mr. Pelzel was President and Chief Executive Officer of Invenux Inc., a privately-held biopharmaceutical company from March 2001 to November 2002. Mr. Pelzel also spent 11 years with GlaxoSmithKline in senior-level sales, marketing and international operational positions, including Country Manager of Hong Kong and China. He spent 13 years with American Home Products, focused

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primarily on their antibiotics business. During his career, he directed the launch of five major pharmaceutical products, many on a global basis. Mr. Pelzel has a B.A. degree from Hartwick College of Oneonta, New York and a Masters degree in Natural Sciences from the University of Paris.

        Kera Alexander has served as Vice President, Administration and Human Resources since October 2007, after having served as Senior Director, Corporate Administration and Human Resources since March 2005. Ms. Alexander joined the Company in February 1997. Prior to joining Depomed, Ms. Alexander held various positions at ALZA Corporation, including Manager, Shareholder Relations. Ms. Alexander received her Professional in Human Resources (PHR) certification in 2005.

        Tammy L. Cameron has served Vice President, Finance since December 2008, after having served as Controller since July 2007. In October 2007, Ms. Cameron was named interim principal financial and accounting officer. From January 2005 to June 2007, Ms. Cameron served as the Controller of Adeza Biomedical Corporation, a publicly-traded medical device company. From 2001 to 2005, Ms. Cameron served as the Director of Finance and Administration of Timi3 Systems, a venture-backed medical device company. Prior to Timi3 Systems, Ms. Cameron served as Director of Treasury and External Reporting of KeraVision, Inc., a publicly-traded medical device company and as a member of Ernst & Young's audit practice. She is a Certified Public Accountant and holds a B.A. degree from California State University, East Bay.

        William Callahan joined Depomed in 2002 and has served as Vice President, Operations since November 2009. Mr. Callahan previously held the position of Senior Director of Operations. Mr. Callahan has spent most of his more than 20-year career in emerging growth companies, establishing and growing operations groups, and participating in the launch of numerous new products. Prior to Depomed, Mr. Callahan held director of operations positions at Avocet Medical, Cygnus Therapeutics, Applied Biosystems and Johnson & Johnson Lifescan. He received a B.S. degree in Chemistry from San Francisco State University.

        Matthew M. Gosling has served as Vice President and General Counsel since June 2006. Before joining Depomed, Mr. Gosling was a partner at Heller Ehrman LLP, a national law firm, where he served a nine-year tenure as a corporate transactional attorney. Mr. Gosling received his law degree from the University of Chicago and holds a B.A. degree from Trinity University, San Antonio, Texas.

        Michael Sweeney, M.D. joined Depomed as Vice President of Research and Development in December 2007. Before joining Depomed, Dr. Sweeney was Vice President of Medical Affairs at CV Therapeutics from August 2003 to September 2007. Prior to CV Therapeutics, Dr. Sweeney spent 11 years at Pfizer Pharmaceuticals in New York and the U.K. where he held a variety of senior-level medical and marketing positions, including Director of Marketing, Viagra Worldwide Team and Global Urology Medical Group Leader for Pfizer's urological products Viagra, Cardura and Detrol. Prior to Pfizer, he served as a senior clinical pharmacologist and a medical advisor at Zeneca PLC. Dr. Sweeney received his M.D. degree from Manchester University in the U.K. together with post graduate diplomas in Pharmaceutical Medicine and Pharmacoepidemiology, the latter from the University of London. He also is a Fellow of the Royal College of Physicians of Edinburgh.

        Thadd M. Vargas has served as Senior Vice President of Business Development since December 2008, after having served as the Company's Vice President of Business Development since December 2002. Before joining the company, Mr. Vargas was Vice President of Finance at Worldres.com, Inc., Director of Finance at Kosan Biosciences, Inc. and Director of Business Development at Anergen, Inc. Prior to Anergen, Mr. Vargas was a member of Ernst & Young's life sciences audit practice. Mr. Vargas holds a B.A. degree in Business Economics from the University of California at Santa Barbara.

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PART II

ITEM 5.    MARKET FOR THE REGISTRANT'S COMMON EQUITY, RELATED SHAREHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

Market Information

        Our common stock trades on the NASDAQ Global Market (NASDAQ) under the symbol "DEPO". The following table sets forth, for the periods indicated, the intraday high and low prices of our common stock as reported by the NASDAQ from January 1, 2009 to December 31, 2010.

        On March 15, 2011, the closing price of our common stock was $8.83. As of March 11, 2011, there were approximately 30 shareholders of record of our common stock, one of which is Cede & Co., a nominee for Depository Trust Company, or DTC. All of the shares of common stock held by brokerage firms, banks and other financial institutions as nominees for beneficial owners are deposited into participant accounts at DTC, and are therefore considered to be held of record by Cede & Co. as one shareholder.

Dividends

        We have never declared or paid any cash dividends on our common stock. We currently intend to retain any future earnings to finance the growth and development of our business.

Issuer Purchases of Securities

        We did not repurchase any of our equity securities during the fourth quarter of the year ended December 31, 2010.

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Stock Price Performance Graph

        The following graph compares total shareholder returns of Depomed for the past five years to two indices: the NASDAQ Composite Index and the NASDAQ Biotechnology Index. The total return for Depomed's common stock and for each index assumes the reinvestment of all dividends, although cash dividends have never been declared on Depomed's common stock.

COMPARISON OF 5 YEAR CUMULATIVE TOTAL RETURN*
Among Depomed, Inc., The NASDAQ Composite Index
And The NASDAQ Biotechnology Index

*

$100 invested on 12/31/05 in stock or index, including reinvestment of dividends.
Fiscal year ending December 31.

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ITEM 6.    SELECTED FINANCIAL DATA

        The data set forth below is not necessarily indicative of the results of future operations and should be read in conjunction with the financial statements and the notes included elsewhere in this annual report on Form 10-K and also with "ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS."

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ITEM 7.    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

OVERVIEW

        Depomed is a specialty pharmaceutical company focused on the development and commercialization of differentiated products that address large and growing markets and are based on proprietary oral drug delivery technologies. In January 2011, the U.S. Food and Drug Administration (FDA) approved Gralise^TM (gabapentin) once-daily tablets for the management of postherpetic neuralgia. In March 2011, we and our former licensee, Abbott Products, terminated our Gralise exclusive license agreement and the rights to Gralise reverted back to us. We intend to commercialize Gralise on our own or with the assistance of a promotion partner or licensee.

        In October 2009, we announced the results of Breeze 1 and Breeze 2, our Phase 3 clinical trials for Serada, our proprietary extended release formulation of gabapentin for the treatment of menopausal hot flashes. The higher dose formulation of Serada evaluated in the studies met five of eight co-primary endpoints across the two studies, while the lower dose formulation evaluated met four of eight co-primary endpoints. In August 2010, we commenced one additional Phase 3 clinical trial evaluating Serada for menopausal hot flashes, known as Breeze 3, after reaching an agreement with the FDA regarding a Special Protocol Assessment (SPA) on the design and analysis of Breeze 3. In March 2011, we completed enrollment in Breeze 3.

        We seek to optimize the use and value of our product candidates and drug delivery technologies in three ways. First, we are seeking to assemble a number of pharmaceutical products that can be highly differentiated from immediate release versions of the compounds upon which they are based and may be promoted together within a specialty pharmaceutical field, such as women's health care providers. Our development of Serada, and our retention of co-promotion rights within the obstetrics/gynecology field in our commercialization arrangements with Covidien, Ltd. (Covidien) and Santarus, Inc. (Santarus), are examples of this aspect of our business strategy. Second, we out-license product candidates after we have increased their value through our formulation and clinical development efforts. Third, we enter into collaborative partnerships with other companies where the unique capabilities of our technology can provide superior value to a partner's product candidate, resulting in greater value for Depomed than traditional fee-for-service arrangements. Our license and development arrangements with Covidien, Janssen Pharmaceutica N.V. (Janssen) and Boehringer Ingelheim GMBH (Boehringer Ingelheim) and our license agreement with Merck & Co., Inc. (Merck) are examples of this strategy.

        In addition to Gralise, we have developed two other products which have been approved by the FDA. Glumetza® (metformin hydrochloride extended-release tablets) is a once-daily treatment for adults with type 2 diabetes that we commercialize in the United States with Santarus. Proquin® XR (ciprofloxacin hydrochloride) is a once-daily treatment for uncomplicated urinary tract infections that we no longer manufacture or market.

CRITICAL ACCOUNTING POLICIES AND ESTIMATES

        A detailed discussion of our significant accounting policies can be found in Note 1 of the Notes to Financial Statements, and the impact and risks associated with our accounting policies are discussed throughout this Annual Report on Form 10-K and in the footnotes to the financial statements. Critical accounting policies are those that require significant judgment and/or estimates by management at the time that financial statements are prepared such that materially different results might have been reported if other assumptions had been made. We consider certain accounting policies related to revenue recognition, accrued liabilities, stock-based compensation and use of estimates to be critical policies. These estimates form the basis for making judgments about the carrying values of assets and liabilities. We base our estimates and judgments on historical experience and on various other

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assumptions that we believe to be reasonable under the circumstances. Actual results could differ materially from these estimates.

        We believe the following policies to be the most critical to an understanding of our financial condition and results of operations because they require us to make estimates, assumptions and judgments about matters that are inherently uncertain.

Revenue Recognition

        We recognize revenue from the sale of Glumetza and Proquin XR products, and from license fees, milestones and royalties earned on license agreements and collaborative arrangements. Revenue arrangements with multiple elements are divided into separate units of accounting if certain criteria are met, including whether the delivered element has stand-alone value to the customer and whether there is objective and reliable evidence of the fair value of the undelivered items. The consideration received is allocated among the separate units based on their respective fair values, and the applicable revenue recognition criteria are applied to each of the separate units.

        Revenue is recognized when there is persuasive evidence that an arrangement exists, delivery has occurred and title has passed, the price is fixed or determinable and we are reasonably assured of collecting the resulting receivable.

Product Sales

        We sell Glumetza product to wholesalers and retail pharmacies that is subject to rights of return within a period beginning six months prior to, and ending twelve months following product expiration. We began shipping Glumetza product to customers in the third quarter of 2006. We currently recognize revenue on shipments of Glumetza product at the time title transfers to our customers, which occurs at the time our product is shipped and delivered to the customer. Prior to the third quarter of 2008, we were unable to reasonably estimate expected returns of the product at the time of shipment, and therefore, deferred revenue on product shipments of Glumetza until the product was dispensed through patient prescriptions. The quantity of prescription units dispensed was estimated based on analysis of third-party information, including third-party market research data and information obtained from wholesalers with respect to inventory levels and inventory movement. Based on the shipment trends, prescription trends and product returns history for Glumetza over two years through the third quarter of 2008 and based on an analysis of return rates of companies with products that have similar characteristics and similar return policies within the metformin prescription market, we concluded that we had the information needed to reasonably estimate product returns during the third quarter of 2008. Beginning in the third quarter of 2008, we began recognizing revenue for Glumetza sales as revenue at the time of shipment to our customers. Consequently, in 2008, we recognized a one time increase of $6.3 million in net product sales of Glumetza, representing product sales previously deferred, net of estimated product returns, managed care and Medicaid rebates, wholesaler and retail pharmacy fees and discounts, chargebacks and prompt payment discounts. Deferred costs related to shipments of Glumetza previously deferred were also recognized to cost of sales. This change resulted in a one-time $5.3 million reduction of net loss for 2008. Revenues from Glumetza product sales are recorded net of estimated product returns, managed care rebates, wholesaler and retail pharmacy fees and discounts, prompt payment discounts, patient support programs, chargebacks, and Medicaid rebates. These gross-to-net sales adjustments are recognized in the same period the related revenue is recognized and are based on estimates of the amounts earned or to be claimed on the related sales.

        We obtained the rights back from Esprit Pharma (Esprit) to market Proquin XR product in July 2007, and began selling Proquin XR to wholesalers and retail pharmacies in October 2007. Given the declining prescription demand and high percentage of returns of Proquin XR, we currently cannot reliably estimate expected returns of the product at the time of shipment. Accordingly, we defer

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recognition of revenue on product shipments of Proquin XR until the right of return no longer exists, which occurs at the earlier of the time Proquin XR units are dispensed through patient prescriptions or expiration of the right of return. We estimate patient prescriptions dispensed using an analysis of third-party information, including third-party market research data and information obtained from wholesalers with respect to inventory levels and inventory movement. We have not had significant history estimating the number of patient prescriptions dispensed for Proquin XR. If we underestimate or overestimate patient prescriptions dispensed for a given period, adjustments to revenue may be necessary in future periods. We have a deferred revenue balance of $1.0 million at December 31, 2010 related to Proquin XR product shipments that have not been recognized as revenue, which is net of wholesaler and retail pharmacy fees and discounts and prompt payment discounts. In addition, the costs of manufacturing Proquin XR associated with the deferred revenue are recorded as deferred costs, which are included in inventory, until such time the deferred revenue is recognized. Revenues from Proquin XR product sales are recorded net of estimated wholesaler and retail pharmacy fees and discounts, prompt payment discounts, chargebacks and Medicaid rebates. These gross-to-net sales adjustments are recognized in the same period the related revenue is recognized and are based on estimates of the amounts earned or to be claimed on the related sales.

        We have ceased manufacturing of Proquin XR and stopped shipping Proquin XR to customers during the fourth quarter of 2010.

Product Sales Allowances

        We recognize product sales allowances as a reduction of product sales in the same period the related revenue is recognized. Product sales allowances are based on amounts owed or to be claimed on the related sales. These estimates take into consideration the terms of our agreements with customers, historical product returns, rebates or discounts taken, estimated levels of inventory in the distribution channel, the shelf life of the product, and specific known market events, such as competitive pricing and new product introductions. If actual future results vary from our estimates, we may need to adjust these estimates, which could have an effect on product sales and earnings in the period of adjustment. Our product sales allowances include:

•

Product Returns—We allow customers to return product for credit on returned product that is within six months before and up to one year after its product expiration date.



•

Managed Care Rebates—We offer discounts under contracts with certain managed care providers who do not purchase directly from us. We generally pay managed care rebates one to two months after the quarter in which prescriptions subject to the rebate are filled.



•

Wholesaler and Retail Pharmacy Discounts—We offer contractually determined discounts to certain wholesale distributors and retail pharmacies that purchase directly from us. These discounts are either taken off-invoice at the time of shipment or paid to the customer on a quarterly basis one to two months after the quarter in which product was shipped to the customer.



•

Prompt Pay Discounts—We offer cash discounts to our customers, generally 2% of the sales price, as an incentive for prompt payment. Based on our experience, the Company expects its customers to comply with the payment terms to earn the cash discount.



•

Medicaid Rebates—We participate in Medicaid rebate programs, which provide assistance to certain low-income patients based on each individual state's guidelines regarding eligibility and services. Under the Medicaid rebate programs, we pay a rebate to each participating state, generally two to three months after the quarter in which prescriptions subject to the rebate are filled.

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•

Chargebacks—We provide discounts to authorized users of the Federal Supply Schedule (FSS) of the General Services Administration under an FSS contract with the Department of Veterans Affairs. These federal entities purchase products from the wholesale distributors at a discounted price, and the wholesale distributors then charge back to us the difference between the current retail price and the price the federal entity paid for the product.



•

Patient Discount Programs—We offer loyalty card programs for Glumetza in which patients receive certain discounts off their prescription at participating retail pharmacies. The discounts are reimbursed by the Company approximately one to two months after the prescription subject to the discount is filled.

        We believe our estimates related to gross-to-net sales adjustments for wholesaler and retail pharmacy fees and discounts, prompt payment discounts, patient discount programs and chargebacks do not have a high degree of estimation complexity or uncertainty as the related amounts are settled within a relatively short period of time. We believe that our estimated product return allowances and estimated rebates for Glumetza require a high degree of judgment and are subject to change based on our experience and certain quantitative and qualitative factors.

        Beginning in the third quarter of 2008, we began recognizing Glumetza product sales at time title transfers to our customer, and provide for an estimate of future product returns at that time. We monitor actual return history on individual product lot basis since product launch, which provides us with a basis to reasonably estimate future product returns, taking into consideration the shelf life of product, shipment and prescription trends, estimated distribution channel inventory levels, and consideration of the introduction of competitive products. The shelf life of the 500mg Glumetza is currently 48 months from the date of tablet manufacture. On product launch in August 2006 and through the second quarter of 2008, the shelf life of 500mg Glumetza product shipped was 36 months from the date of tablet manufacture. The shelf life of the 1000mg Glumetza is currently 24 to 36 months from the date of tablet manufacture. In 2010, based on our review of actual product returns through the end of 2010, we increased our estimate for Glumetza product returns. This resulted in a decrease of product sales of approximately $1.1 million in 2010 related to sales made in prior periods.

        Because of the shelf life of Glumetza product and our return policy of issuing credits on returned product that is within six months before and up to one year after its product expiration date, there may be a significant period of time between when the product is shipped and when we issue credits on returned product. Accordingly, we may have to adjust these estimates, which could have an effect on product sales and earnings in the period of adjustments. A 1% increase or decrease in our returns reserve estimates as a percentage of product shipped, would have a cumulative financial statement impact of approximately $2.0 million for the year ended December 31, 2010.

        Our rebate accruals for Glumetza are based on definitive contractual agreements with managed care providers related to the dispensing of Glumetza under their respective medical benefit plans. Rebates are accrued at the time of sale, and typically are paid out several months after the sale. We estimate rebates based on current and anticipated future patient usage, the applicable contractual rebate rate amounts, and our estimates of the quantity of product in the distribution channel.

        Our product sales allowances and related accruals are evaluated each reporting period and adjusted when trends or significant events indicate that a change in estimate is appropriate. Such changes in estimate could materially affect our results of operations of financial position.

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        A rollforward of our product sales allowances for the three years ended December 31, 2010 is as follows:

License and Collaborative Arrangements

        Revenue from license and collaborative arrangements, including license fees creditable against future royalty obligations (if any), of the licensee, is recognized when an arrangement is entered into if

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we have substantially completed our obligations under the terms of the arrangement and our remaining involvement is inconsequential and perfunctory. If we have significant continuing involvement under such an arrangement, license fees are deferred and recognized over the estimated performance period. License fee and collaborative payments received in excess of amounts earned are classified as deferred revenue until earned.

        We recognize milestone payments upon the achievement of specified milestones if (1) the milestone is substantive in nature, and the achievement of the milestone was not reasonably assured at the inception of the agreement, (2) achievement relates to past performance and (3) the fees are nonrefundable. Milestone payments received in excess of amounts earned are classified as deferred revenue until earned.

Research and Development Expense and Accruals

        Research and development expenses include related salaries, clinical trial costs, consultant fees, supplies, manufacturing costs for research and development programs and allocations of corporate costs. All such costs are charged to research and development expense as incurred. These expenses result from our independent research and development efforts as well as efforts associated with collaborations. Our expense accruals for clinical trials are based on estimates of the services received from clinical trial centers and clinical research organizations. If possible, we obtain information regarding unbilled services directly from service providers. However, we may be required to estimate these services based on information available to our product development or administrative staff. If we underestimate or overestimate the activity associated with a study or service at a given point in time, adjustments to research and development expenses may be necessary in future periods. Historically, our estimated accrued liabilities have approximated actual expense incurred.

Stock-Based Compensation

        The Company estimates the fair value of stock options and Employee Stock Purchase Plan (ESPP) shares using the Black-Scholes valuation model. The Black-Scholes model requires the input of highly subjective assumptions. The most significant assumptions are our estimates of the expected volatility and the expected term of the award.

        Risk-Free Interest Rate.    The risk-free interest rate is based on the implied yield available on U.S. Treasury zero-coupon issues with a remaining term equal to the expected term of the option.

        Expected Volatility.    The volatility assumption is based on the historical volatility of our common stock over the expected term of the options.

        Expected Life of Options.    Beginning on January 1, 2010, the Company uses historical option exercise data to estimate the expected life of the options. In 2008 and 2009, the Company's historical share option exercise experience did not provide a reasonable basis upon which to estimate expected term because of a lack of sufficient data points, and the Company estimated the expected term by using the weighted average terms of a peer group of companies that grant options with similar vesting provisions.

        Expected Dividend Yield.    The Company has never paid any dividends and does not intend to in the near future.

        As required, we review our valuation assumptions at each grant date and, as a result, we are likely to change our valuation assumptions used to value employee stock-based awards granted in future periods. Employee and director stock-based compensation costs are to be recognized over the vesting period of the award, and we have elected to use the straight-line attribution method.

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        Forfeitures are to be estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. We estimate forfeitures based on historical experience.

Fair Value Measurements

        Effective January 1, 2008, the Company adopted the authoritative guidance for fair value measurements, which defines fair value and provides guidance for using fair value to measure certain assets and liabilities. This authoritative guidance applies whenever other standards require or permit assets or liabilities to be measured at fair value but does not expand the use of fair value in any new circumstances. Accordingly, the carrying amounts of certain of our financial instruments, including cash equivalents and investments, continue to be valued at fair value on a recurring basis. This also requires expanded disclosure of the effect on earnings for items measured using unobservable data, establishes a fair value hierarchy that prioritizes the inputs used to measure fair value and requires separate disclosure by level within the fair value hierarchy.

        As defined in authoritative guidance for fair value measurements, fair value is the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the measurement date. We utilize market data or assumptions that we believe market participants would use in pricing assets or liabilities, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs can be readily observable, market corroborated or generally unobservable. We apply the market approach valuation technique for fair value measurements and maximize the use of observable inputs and minimize the use of unobservable inputs. All of our cash equivalents and marketable securities are valued using quoted prices in active markets and are valued at Level 1 or Level 2 within the fair value hierarchy.

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RESULTS OF OPERATIONS

Revenues

        Total revenues are summarized in the following table (in thousands):

Product sales

Glumetza

        The increase in Glumetza product sales in 2010 from 2009 was primarily driven by increased penetration of the 1000mg Glumetza in the metformin prescription market resulting from the promotion efforts by our promotion partner, Santarus, as well as price increases. This was offset by lower product sales of the 500mg Glumetza resulting from the voluntary 500mg Glumetza recall in 2010. We temporarily suspended product shipments of 500mg Glumetza product in June 2010 to our customers and did not resume shipments until January 2011. Glumetza product sales in 2010 included returns of approximately $1.3 million related to credits for returns given to customers on returns of recalled 500mg Glumetza product, which had the effect of reducing product sales. The 1000mg Glumetza product was not subject to the recall.

        The increase in Glumetza product sales in 2009 from 2008 was primarily driven by increased penetration in the metformin prescription market resulting from the promotion efforts of Santarus, and to a lesser extent, price increases in 2009. We began selling the 1000mg Glumetza in June 2008. Accordingly, 2009 included a full-year of selling the 1000mg Glumetza as compared to a partial year in 2008.

        As noted above under "CRITICAL ACCOUNTING POLICIES—Revenue Recognition", beginning in the third quarter of 2008, we began to recognize Glumetza product sales at the time title transfers to our customer, and provide for an estimate of future product returns at that time. This resulted in a one-time increase for the year ended December 31, 2008, of $6.3 million in net product sales of Glumetza, representing product sales previously deferred, net of estimated product returns, managed

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care and Medicaid rebates, wholesaler and retail pharmacy fees and discounts, chargebacks and prompt payment discounts.

        Since October 2008, Glumetza has been promoted by Santarus. From February 2008 through September 2008, we promoted Glumetza through a contract sales organization. In October 2007, we terminated our promotion agreement related to Glumetza with King Pharmaceuticals, who promoted Glumetza since its launch in August 2006, and King's promotion obligations ended in December 2007.

        Product sales for Glumetza relative to its current runrate will depend in part on the success of our promotion partner, Santarus, as well any price adjustments.

Proquin XR

        In October 2007, we re-launched Proquin XR with Watson, and began selling to wholesalers and retail pharmacies. We defer recognition of revenue on product shipments of Proquin XR until the right of return no longer exists, which occurs at the earlier of the time Proquin XR units are dispensed through patient prescriptions or expiration of the right of return. At December 31, 2010, we have a deferred revenue balance, which is classified as a liability on the balance sheet, of $1.0 million associated with the deferral of revenue on Proquin XR product shipments, which is net of estimated wholesaler fees, retail pharmacy discounts, stocking allowances and prompt payment discounts.

        The decrease in Proquin XR product sales in 2010 as compared to 2009 is a result of decreased Proquin XR promotion efforts. In February 2009, we amended our promotion agreement with Watson, pursuant to which Watson performed a specified number of details in the first quarter of 2009. The agreement with Watson terminated effective December 31, 2009, and we had no sales force or promotion partner promoting Proquin XR to physicians in 2010.

        We ceased shipments of Proquin XR to wholesalers and retail pharmacies in the fourth quarter of 2010.

Royalties

Glumetza

        Glumetza royalties relate to royalties we received from Valeant Pharmaceuticals International, Inc. (Valeant), based on net sales of Glumetza in Canada and royalties we received from LG based on net sales of LG's version of Glumetza, Novamet GR, in Korea. We began receiving royalties from Valeant in the first quarter of 2006 and from LG in the first quarter of 2007.

Teva

        In April 2008, we entered into a settlement and license agreement with Teva Pharmaceuticals USA, Inc. (Teva) associated with our patent infringement lawsuit against Teva affiliates IVAX Corporation and IVAX Pharmaceuticals, Inc. related to Teva's generic Glucophage XR tablets. In connection with the settlement and license agreement we were entitled to receive up to a total of $2.5 million in future royalties on Teva's generic Glucophage XR product in the United States. The $2.5 million cap in royalties was met in 2009.

License and Collaborative Revenue

Gralise

        The increase in Gralise license and collaborative revenue in 2010 over 2009 relates to the $10.0 million milestone payment from Abbott Products in June 2010 on FDA acceptance of the NDA for Gralise for the treatment of postherpetic neuralgia. Because the non-refundable milestone was

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substantive in nature, achieved and based on past performance, the entire $10.0 million was recognized as license revenue in the second quarter of 2010.

        The remaining portion of Gralise license and collaborative revenue relates to the $25.0 million upfront license payment received from Abbott Products in the fourth quarter of 2008 under our license agreement granting Abbott Products exclusive rights to develop and commercialize Gralise in the United States, Canada and Mexico for pain indications. We are recognizing the $25.0 million upfront payment received from Abbott Products as revenue ratably until January 2013, which represented the expected maximum length of time our development and supply obligations exist under the agreement.

Glumetza

        Glumetza license revenue for the year ended December 31, 2010 consisted primarily of license revenue recognized from the $25.0 million license fee received from Valeant in July 2005 and from the $12.0 million upfront fee received from Santarus in July 2008. We are recognizing the $25.0 million license fee payment from Valeant as revenue ratably until October 2021, which represents the estimated length of time our obligations exist under the arrangement related to royalties we are obligated to pay Valeant on net sales of Glumetza in the United States and for our obligation to use Valeant as our sole supplier of the 1000mg Glumetza. We are recognizing the $12.0 million upfront payment from Santarus as revenue ratably until October 2021, which represents the estimated length of time our obligations exist under the arrangement related to promotion fees we are obligated to pay Santarus on gross margin of Glumetza in the United States.

Covidien

        In November 2008, we entered into a license agreement with Covidien granting Covidien worldwide rights to utilize our Acuform technology for the exclusive development of four products containing acetaminophen in combination with opiates. In 2008, Covidien paid us a total of $5.5 million in upfront fees, representing a $4.0 million upfront license fee and a $1.5 million upfront payment for formulation work to be performed by Depomed under the agreement. The entire $5.5 million was initially accounted for as a single unit of accounting and being amortized ratably through November 2011, which was initially the estimated length of time Depomed was obligated to perform formulation work under the agreement.

        The development of each of the four products was to begin by November 2010. Depomed's formulation obligations related to the first and second products were completed in October 2009 and September 2010, respectively. Covidien did not elect to initiate development of the remaining two products under the agreement by November 2010 and under the agreement, Depomed was no longer required to perform formulation work on those two products. Accordingly, Depomed's formulation obligations were completed during the fourth quarter of 2010. As Depomed no longer has any substantive continuing performance obligations, all remaining deferred revenue related to the $5.5 million in upfront license fees previously received from Covidien was fully recognized as revenue in the fourth quarter of 2010. This resulted in a one-time increase in license revenue of $1.8 million during the fourth quarter of 2010.

        Through December 31, 2010, we have also recognized a total of $1.5 million in milestone revenue under the agreement. In October 2009, the first formulation was completed by us and delivered to Covidien, which triggered a $0.5 million milestone payment from Covidien to us in October 2009. In September 2010, we recognized $0.5 million on completion and delivery of the second formulation under the agreement to Covidien, and an additional $0.5 million on the first formulation under the agreement entering clinical development. Because each of the non-refundable milestones were substantive in nature, based on past performance and achievement was not reasonably assured at the

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inception of the agreement, each of the milestones was recognized as revenue in its entirety upon achievement.

Janssen

        In August 2010, we entered into a non-exclusive license agreement with Janssen granting Janssen a license to certain patents related to the Company's Acuform drug delivery technology to be used in developing fixed dose combinations of canagliflozin and extended release metformin. Janssen paid us a $5.0 million upfront license fee associated with the license agreement. The $5.0 million is being amortized ratably through March 2011, which is the estimated length of time Depomed is obligated to perform formulation work under the agreements. We recognized approximately $3.1 million of revenue associated with this upfront license fee during the year ended December 31, 2010.

        We also entered into a service agreement with Janssen under which we provide formulation work for Janssen and are reimbursed by Janssen on an agreed-upon FTE rate per hour plus out-of-pocket expenses. We recognized approximately $0.8 million of revenue associated with the reimbursement of formulation work under the service agreement during 2010.

        In September 2010, we achieved the first development milestone under the agreement related to formulation work, which triggered a $5.0 milestone from Janssen to us. The non-refundable $5.0 million milestone was received in October 2010. As the milestone was substantive in nature, and the achievement of the milestone was not reasonably assured at the inception of the agreement, we recognized the $5.0 million milestone in its entirety as license revenue during the third quarter of 2010.

Merck

        Merck license revenue for the year ended December 31, 2009 relates to the $10.0 million upfront payment received from Merck in August 2009 under our non-exclusive license agreement granting Merck a license to certain patents related to the Company's metformin extended release technology to be used in developing fixed dose combinations of sitagliptin and extended release metformin. As the Company has no continuing obligations under the agreement, the $10.0 million upfront payment was fully recognized as license revenue on receipt in the third quarter of 2009.

        In October 2010, the Company received a $2.5 million development milestone from Merck under the license agreement related to the acceptance of the NDA application of Merck's combination product subject to the agreement. As the milestone was substantive in nature, and the achievement of the milestone was not reasonably assured at the inception of the agreement, we recognized the $2.5 million milestone in its entirety as license revenue during the fourth quarter of 2010.

DM-1992

        DM-1992 revenue in 2010, 2009 and 2008 represents grants received by the Michael J. Fox Foundation in relation to our DM-1992 product candidate for Parkinson's Disease.

Cost of Sales

        Cost of sales consists of costs of the active pharmaceutical ingredient, contract manufacturing and packaging costs, inventory write-downs, product quality testing, internal employee costs related to the manufacturing process, distribution costs and shipping costs related to our product sales of GLUMETZA and Proquin XR. Total costs of sales are summarized in the following table (in thousands):