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AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON SEPTEMBER 19, 2008
REGISTRATION NO. 333-125731
 
 
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
Post-Effective Amendment No. 1 to
FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
HALOZYME THERAPEUTICS, INC.
(Exact Name of Registrant as Specified in Its Charter)
     
DELAWARE
(State or Other Jurisdiction
of Incorporation or Organization)
  88-0488686
(IRS Employer
Identification Number)
11388 Sorrento Valley Road
San Diego, California 92121
(858) 794-8889

(Address, Including Zip Code, and Telephone Number, Including
Area Code, of Registrant’s Principal Executive Offices)
David A. Ramsay
Halozyme Therapeutics, Inc.
11388 Sorrento Valley Road
San Diego, California 92121
(858) 794-8889

(Name, Address, Including Zip Code, and Telephone Number, Including
Area Code, of Agent for Service)
COPIES TO:
Douglas J. Rein, Esq.
DLA Piper LLP (US)
4365 Executive Drive, Suite 1100
San Diego, CA 92121-2133
Telephone: (858) 677-1400
Facsimile: (858) 677-1477
APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC:
From time to time after the effective date of this Registration Statement.
If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o
If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. þ
If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o
If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o
If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. o
If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. o
     Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):
Large accelerated filer o Accelerated filer þ  Non-accelerated filer o
(Do not check if a smaller reporting company)
Smaller reporting company o
THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF THE SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(a), MAY DETERMINE.
 
 

 


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EXPLANATORY NOTE
     Halozyme Therapeutics, Inc., a Delaware corporation, (“Halozyme Delaware”), as successor to Halozyme Therapeutics, Inc., a Nevada corporation (“Halozyme Nevada”), is filing this Post-Effective Amendment No. 1 (this “Amendment”) to Registration Statement No. 333-125731 (the “Registration Statement”) pursuant to Rule 414(d) promulgated under the Securities Act of 1933, as amended (the “Securities Act”), as a result of the registrant’s reincorporation in the State of Delaware from the State of Nevada (the “Reincorporation”). Except as modified by this Amendment, Halozyme Delaware expressly adopts the Registration Statement as its own registration statement effective as of the date of the Reincorporation for all purposes of the Securities Act and the Securities Exchange Act of 1934, as amended.
     Halozyme Nevada effected the Reincorporation by merging into its wholly-owned subsidiary Halozyme Delaware pursuant to the terms of an Agreement and Plan of Merger between Halozyme Nevada and our company. At the effective time of the merger:
    each outstanding share of common stock of Halozyme Nevada was converted into one share of common stock of Halozyme Delaware;
 
    Halozyme Delaware assumed all equity-based award plans and grants previously adopted by Halozyme Nevada (the “Equity Plans”) and reserved for issuance under each Equity Plan a number of its shares of common stock equal to the number of shares of stock which had been reserved under that Equity Plan by Halozyme Nevada;
 
    each outstanding option or other right to purchase and each outstanding equity-based award relating to shares of Halozyme Nevada common stock became an option or right to purchase, or an award relating to, the same number of shares of Halozyme Delaware common stock, subject to the same terms and conditions, including the per share exercise or conversion price; and
 
    Halozyme Nevada ceased to exist as a separate legal entity.
     The Reincorporation did not result in any material change to the registrant’s business, management, assets, liabilities or net worth. The Halozyme Delaware common stock has continued to be listed on the NASDAQ Global Market under the same ticker symbol, “HALO”.
     As a result of the Reincorporation, holders of Halozyme Nevada common stock became holders of Halozyme Delaware common stock, and their rights as holders of Halozyme Delaware common stock are governed by the General Corporation Law of the State of Delaware and Halozyme Delaware’s Certificate of Incorporation and Bylaws. A description of the differences between the rights of holders of Halozyme Nevada common stock and Halozyme Delaware common stock is provided in the registrant’s definitive Proxy Statement filed by Halozyme with the SEC October 11, 2007, under the headings “Significant Differences Between the Corporate Laws of Nevada and Delaware” and “Significant Differences Between Our Current Charter Documents and the Charter Documents of Halozyme Delaware,” which descriptions are incorporated herein by reference and made a part hereof.
     Pursuant to our Registration Statement on Form S-3 (Reg. No. 333-125731), we originally registered up to $50 million in aggregate principal amount of our common stock, preferred stock, debt securities and/or warrants. We previously sold an aggregate of $17.5 million of our common stock under the Registration Statement on Form S-3 (Reg. No. 333-125731) pursuant to a prospectus supplement filed with the SEC on December 13, 2005 and a prospectus supplement filed with the SEC on December 14, 2005. This Post-Effective Amendment No. 1 relates to the remaining $32.5 million in aggregate principal amount of our common stock, preferred stock, debt securities and/or warrants that we may offer and sell pursuant to our Registration Statement on Form S-3 (Reg. No. 333-125731).

 


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SUBJECT TO COMPLETION, DATED SEPTEMBER 19, 2008

The information in this prospectus is not complete and may be changed. We may not sell these securities under this prospectus until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell nor does it seek an offer to buy these securities in any state where the offer and sale would not be permitted.

PROSPECTUS
$32,500,000
HALOZYME THERAPEUTICS, INC.
Common Stock
Preferred Stock
Debt Securities
Warrants
 
     We may from time to time issue, in one or more series or classes, up to $32,500,000 in aggregate principal amount of our common stock, preferred stock, debt securities and/or warrants. We may offer these securities separately or together. We will specify in the accompanying prospectus supplement the terms of the securities being offered. We may sell these securities to or through underwriters and also to other purchasers or through agents. We will set forth the names of any underwriters or agents, and any fees, conversions, or discount arrangements, in the accompanying prospectus supplement. We may not sell any securities under this prospectus without delivery of the applicable prospectus supplement.
     We will provide the specific terms of these securities in supplements to this prospectus. Any prospectus supplement may also add, update or change information contained in this prospectus. You should read this prospectus and any accompanying prospectus supplement carefully before you invest. THIS PROSPECTUS MAY NOT BE USED TO OFFER OR SELL ANY SECURITIES UNLESS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT.
     Our common stock is listed on The Nasdaq Global Market under the symbol “HALO.” On September 16, 2008, the last reported sale price for our common stock was $7.48 per share.
     The securities offered by this prospectus or any prospectus supplement may be offered directly to investors or to or through underwriters, dealers or other agents. If any underwriters or dealers are involved in the sale of any securities offered by this prospectus and any prospectus supplement, their names, and any applicable purchase price, fee, commission or discount arrangement between or among them, will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement.
 
     INVESTING IN OUR SECURITIES INVOLVES A HIGH DEGREE OF RISK. SEE “RISK FACTORS” BEGINNING ON PAGE 2 FOR A DISCUSSION OF MATERIAL RISKS YOU SHOULD CONSIDER BEFORE YOU INVEST IN OUR SECURITIES.
 
     NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED THESE SECURITIES OR DETERMINED IF THIS PROSPECTUS IS TRUTHFUL OR COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.
 
THE DATE OF THIS PROSPECTUS IS SEPTEMBER      , 2008.

 


 

     
 
     You should rely only on the information provided or incorporated by reference in this prospectus. We have not authorized anyone to provide you with additional or different information. This document may only be used where it is legal to sell these securities. You should not assume that any information in this prospectus is accurate as of any date other than the date of this prospectus. Information incorporated by reference in this prospectus is accurate only as of the date of the document incorporated by reference. In this prospectus, unless otherwise indicated, the words “Halozyme,” “we,” “us,” and “our” refer to Halozyme Therapeutics, Inc. and its subsidiaries.
 
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 EXHIBIT 5.1
 EXHIBIT 23.1
 EXHIBIT 23.2
FORWARD-LOOKING STATEMENTS
     This prospectus, including the documents that we incorporate by reference, contains forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act. Any statements about our expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and may be forward-looking. These statements are often, but are not always, made through the use of words or phrases such as “anticipates,” “estimates,” “plans,” “projects,” “continuing,” “ongoing,” “expects,” “management believes,” “we believe,” “we intend” and similar words or phrases. Accordingly, these statements involve estimates, assumptions and uncertainties which could cause actual results to differ materially from those expressed in them. Any forward-looking statements are qualified in their entirety by reference to the factors discussed throughout this prospectus, and in particular those factors listed under the section entitled “Risk Factors.”
     Because the factors referred to in the preceding paragraph could cause actual results or outcomes to differ materially from those expressed in any forward-looking statements we make, you should not place undue reliance on any such forward-looking statements. Further, any forward-looking statement speaks only as of the date on which it is made, and we undertake no obligation to update any forward-looking statement or statements to reflect events or circumstances after the date on which such statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, and it is not possible for us to predict which factors will arise. In addition, we cannot assess the impact of each factor on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements.

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PROSPECTUS SUMMARY
     The following summary highlights selected information from this prospectus and in information incorporated by reference. Because this is a summary, it does not contain all the information about us that may be important to you. You should read this entire prospectus and the other documents and the financial statements and related notes which are incorporated by reference in this prospectus.
Our Business
     We are a biopharmaceutical company developing and commercializing products targeting the extracellular matrix for the drug delivery, metabolism, oncology, and dermatology markets. Our portfolio of products is based on intellectual property covering the family of human enzymes known as hyaluronidases. Hyaluronidases are enzymes (proteins) that break down hyaluronic acid which is a naturally occurring substance in the human body. Our technology is based on our proprietary recombinant human PH20 enzyme, or rHuPH20, a human synthetic version of hyaluronidase that degrades hyaluronic acid, a space-filling, gel-like substance that is a major component of tissues throughout the body, such as skin and bone. The PH20 enzyme is a naturally occurring enzyme that digests hyaluronic acid to temporarily break down the gel, thereby facilitating the penetration and diffusion of other drugs and fluids that are injected under the skin or in the muscle. We have key collaborative agreements with Baxter Healthcare Corporation, or Baxter, and F. Hoffmann-La Roche, Ltd and Hoffmann-La Roche, Inc., or collectively Roche.
     Our operations to date have been focused on organizing and staffing Halozyme Therapeutics, Inc. and its operating subsidiary, Halozyme, Inc., as well as acquiring, developing and securing its technology and undertaking product development for our existing products and for our product candidates. We have received FDA approval for two products: Cumulase®, for use in in-vitro fertilization, and HYLENEX, for use as an adjuvant to increase the absorption and dispersion of other injected drugs and fluids.
     In November 2007, we reincorporated from the State of Nevada to the State of Delaware. Our principal offices and research facilities are located at 11388 Sorrento Valley Road, San Diego, California 92121. Our telephone number is (858) 794-8889 and our e-mail address is info@halozyme.com. Additional information about us can be found on our website at www.halozyme.com, and in our periodic and current reports filed with the Securities and Exchange Commission (“SEC”). Copies of our current and periodic reports filed with the SEC are available at the SEC Public Reference Room at 450 Fifth Street, N.W., Washington, D.C. 20549, and online at www.sec.gov and our website at www.halozyme.com. Please note that the information on our website is not incorporated by reference in this prospectus.
This Prospectus
     This prospectus is part of a registration statement that we filed with the SEC utilizing a “shelf” registration process. Under this shelf process, we may sell the securities described in this prospectus in one or more offerings up to a total dollar amount of $50 million. We have provided in this prospectus a general description of the securities we may offer. Each time we sell securities, we will provide a prospectus supplement that will contain specific information about the terms of that offering. We may also add, update or change in the prospectus supplement any of the information contained in this prospectus. This prospectus, together with applicable prospectus supplements, includes all material information relating to this offering. You should read both this prospectus and any prospectus supplement together with the additional information described under the heading “Where You Can Find More Information.”
Risk Factors
     You should consider carefully all of the information contained in and incorporated by reference in this prospectus, including the information set forth under the caption “Risk Factors,” before making an investment in the securities offered.

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RISK FACTORS
     You should carefully consider the following risk factors before purchasing any of our securities. The risks and uncertainties described below are not the only ones we face. There may be additional risks and uncertainties that are not known to us or that we do not consider to be material at this time. If the events described in these risks occur, our business, financial condition and results of operations would likely suffer. This prospectus contains forward-looking statements that involve risks and uncertainties. Our actual results may differ significantly from the results discussed in the forward-looking statements. This section discusses the risk factors that might cause those differences. You should also consider the additional information set forth in our SEC reports on Forms 10-K, 10-Q and 8-K and in the other documents considered a part of this prospectus. See “Where You Can Find More Information.”
Risks Related To Our Business
We have generated only minimal revenue from product sales to date; we have a history of net losses and negative cash flow, and we may never achieve or maintain profitability.
     We have generated only minimal revenue from product sales to date and may never generate significant revenues from future product sales. Even if we do achieve significant revenues from product sales, licensing revenues and milestone payments, we expect to incur significant operating losses over the next several years. We have never been profitable, and we may never become profitable. Through June 30, 2008, we have incurred aggregate net losses of approximately $86.0 million.
If we do not receive and maintain regulatory approvals for our product candidates, we will not be able to commercialize our products, which would substantially impair our ability to generate revenues.
     With the exception of the December 2004 receipt of a CE (European Conformity) Mark, the April 2005 FDA clearance for Cumulase and the December 2005 FDA approval for our spreading agent, HYLENEX, none of our product candidates has received regulatory approval from the FDA or from any similar national regulatory agency or authority in any other country in which we intend to do business. Approval from the FDA is necessary to manufacture and market pharmaceutical products in the United States. Most other countries in which we may do business have similar requirements.
     Other manufacturers have FDA approved products for use as spreading agents, including ISTA Pharmaceuticals, Inc., or ISTA, with an ovine-derived hyaluronidase, Vitrase®, Amphastar Pharmaceuticals, Inc., or Amphastar, with a bovine-derived hyaluronidase, Amphadase™, and Primapharm, Inc., or Primapharm, also with a bovine-derived hyaluronidase, Hydase™. The FDA has determined that Amphadase, Hydase, HYLENEX and Vitrase are each distinct new chemical entities and hence afforded five years of market exclusivity. The five year market exclusivity precludes identical new chemical entity products from being marketed for a period of five years. For so long as each of these products is established as a distinctly different new chemical entity, the marketing exclusivity granted does not prohibit the marketing of any of these products, including HYLENEX. If the FDA changes its earlier determination that HYLENEX is a distinct new chemical entity, our ability to market HYLENEX will be materially impaired.
     The process for obtaining FDA approval is extensive, time-consuming and costly, and there is no guarantee that the FDA will approve any NDAs that we intend to file with respect to any of our product candidates, or that the timing of any such approval will be appropriate for our product launch schedule and other business priorities, which are subject to change. We have not currently begun the NDA approval process for any of our other potential products, and we may not be successful in obtaining such approvals for any of our potential products.

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We may not receive regulatory approvals for our product candidates for a variety of reasons, including unsuccessful clinical trials.
Clinical testing of pharmaceutical products is a long, expensive and uncertain process and the failure of a clinical trial can occur at any stage. Even if initial results of pre-clinical studies or clinical trial results are promising, we may obtain different results that fail to show the desired levels of safety and efficacy, or we may not obtain FDA approval for a variety of other reasons. The clinical trials of any of our product candidates could be unsuccessful, which would prevent us from obtaining regulatory approval and commercializing the product. FDA approval can be delayed, limited or not granted for many reasons, including, among others:
    FDA officials may not find a product candidate safe or effective enough to merit either continued testing or final approval;
 
    FDA officials may not find that the data from pre-clinical testing and clinical trials justifies approval, or they may require additional studies that would make it commercially unattractive to continue pursuit of approval;
 
    the FDA may reject our trial data or disagree with our interpretations of either clinical trial data or applicable regulations;
 
    the cost of a clinical trial may be greater than what we originally anticipate, and we may decide to not pursue FDA approval for such a trial;
 
    the FDA may not approve our manufacturing processes or facilities, or the processes or facilities of our contract manufacturers or raw material suppliers;
 
    the FDA may change its formal or informal approval requirements and policies, act contrary to previous guidance, or adopt new regulations; or
 
    the FDA may approve a product candidate for indications that are narrow or under conditions that place the product at a competitive disadvantage, which may limit our sales and marketing activities or otherwise adversely impact the commercial potential of a product.
     If the FDA does not approve our product candidates in a timely fashion on commercially viable terms, or if we terminate development of any of our product candidates due to difficulties or delays encountered in the regulatory approval process, it will have a material adverse impact on our business and we will be dependent on the development of our other product candidates and/or our ability to successfully acquire other products and technologies. We may not receive regulatory approval of our Chemophase product candidate or any other product candidates, in a timely manner, or at all.
     We intend to market certain of our products, and perhaps have certain of our products manufactured, in foreign countries. The process of obtaining regulatory approvals in foreign countries is subject to delay and failure for many of the same reasons set forth above as well as for reasons that vary from jurisdiction to jurisdiction. The approval process varies among countries and jurisdictions and can involve additional testing. The time required to obtain approval may differ from that required to obtain FDA approval. We may not obtain foreign regulatory approvals on a timely basis, if at all. Approval by the FDA does not ensure approval by regulatory authorities in other countries or jurisdictions, and approval by one foreign regulatory authority does not ensure approval by regulatory authorities in other foreign countries or jurisdictions or by the FDA.
If we fail to comply with regulatory requirements, regulatory agencies may take action against us, which could significantly harm our business.
     Any approved products, along with the manufacturing processes, post-approval clinical data, labeling, advertising and promotional activities for these products, are subject to continual requirements and review by

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the FDA and other regulatory bodies. Regulatory authorities subject a marketed product, its manufacturer and the manufacturing facilities to continual review and periodic inspections. We will be subject to ongoing FDA requirements, including required submissions of safety and other post-market information and reports, registration requirements, current Good Manufacturing Processes, or cGMP, regulations, requirements regarding the distribution of samples to physicians and recordkeeping requirements. The cGMP regulations include requirements relating to quality control and quality assurance, as well as the corresponding maintenance of records and documentation. We rely on the compliance by our contract manufacturers with cGMP regulations and other regulatory requirements relating to the manufacture of our products. We are also subject to state laws and registration requirements covering the distribution of our products. Regulatory agencies may change existing requirements or adopt new requirements or policies. We may be slow to adapt or may not be able to adapt to these changes or new requirements.
     Later discovery of previously unknown problems with our products, manufacturing processes or failure to comply with regulatory requirements, may result in any of the following:
    restrictions on our products or manufacturing processes;
 
    warning letters;
 
    withdrawal of the products from the market;
 
    voluntary or mandatory recall;
 
    fines;
 
    suspension or withdrawal of regulatory approvals;
 
    suspension or termination of any of our ongoing clinical trials;
 
    refusal to permit the import or export of our products;
 
    refusal to approve pending applications or supplements to approved applications that we submit;
 
    product seizure; or
 
    injunctions or the imposition of civil or criminal penalties.
If any party to a key collaboration agreement, including us, fails to perform material obligations under such agreement, or if a key collaboration agreement is terminated for any reason, our business would significantly suffer.
     We have entered into key collaboration agreements under which we may receive significant future payments in the form of maintenance fees, milestone payments and royalties. In the event that a party fails to perform under a key collaboration agreement, or if a key collaboration agreement is terminated, the reduction in anticipated revenues could delay or suspend our product development activities for some of our product candidates as well as our commercialization efforts for some or all of our products. In addition, the termination of a key collaboration agreement by one of our partners could materially impact our ability to enter into additional collaboration agreements with new partners on favorable terms, if at all. In certain circumstances, the termination of a key collaboration agreement would require us to revise our corporate strategy going forward and reevaluate the applications and value of our technology.

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If we are unable to sufficiently develop our sales, marketing and distribution capabilities or enter into successful agreements with third parties to perform these functions, we will not be able to fully commercialize our products.
     We may not be successful in marketing and promoting our existing product candidates or any other products we develop or acquire in the future. We are currently in the process of developing our sales, marketing and distribution capabilities. However, our current capabilities in these areas are very limited. In order to commercialize any products successfully, we must internally develop substantial sales, marketing and distribution capabilities or establish collaborations or other arrangements with third parties to perform these services. We do not have extensive experience in these areas, and we may not be able to establish adequate in-house sales, marketing and distribution capabilities or engage and effectively manage relationships with third parties to perform any or all of such services. To the extent that we enter into co-promotion or other licensing arrangements, our product revenues are likely to be lower than if we directly marketed and sold our products, and any revenues we receive will depend upon the efforts of third parties, whose efforts may not meet our expectations or be successful.
     We have entered into non-exclusive distribution agreements with MediCult AS, a Denmark-based distributor, and MidAtlantic Diagnostics, Inc., a New Jersey-based distributor, to market and sell our Cumulase product. We have entered into an exclusive sales and marketing agreement with Baxter to market and sell our HYLENEX product in the United States and Puerto Rico. Baxter also has the right to market and sell HYLENEX on an exclusive basis in all territories outside of the United States, if and when we seek and receive the applicable regulatory approvals in those territories.
     We depend upon the efforts of these third parties, such as Baxter, to promote and sell our current products, but there can be no assurance that the efforts of these third parties will meet our expectations or result in any significant product sales. While these third parties are largely responsible for the speed and scope of sales and marketing efforts, they may not dedicate the resources necessary to maximize product opportunities and our ability to cause these third parties to increase the speed and scope of their efforts may be limited. In addition, sales and marketing efforts could be negatively impacted by the delay or failure to obtain additional supportive clinical trial data for our products. Our third party partners are responsible for conducting these additional clinical trials and our ability to increase the efforts and resources allocated to these trials may be limited.
If our sole contract manufacturer is unable to manufacture significant amounts of the active pharmaceutical ingredient used in our products, our product development and commercialization efforts could be delayed or stopped.
     We have signed a commercial supply agreement with Avid Bioservices, Inc., or Avid, a contract manufacturing organization, to produce bulk recombinant human hyaluronidase for clinical trials and commercial use. Avid will produce the active pharmaceutical ingredient used in each of Cumulase, HYLENEX, Chemophase, and Enhanze Technology under cGMP for clinical or commercial scale production and will provide support for the chemistry, manufacturing and controls sections for FDA regulatory filings. Avid has only limited experience manufacturing our active pharmaceutical ingredient batches, and we rely on its ability to successfully manufacture these batches according to product specifications. In addition, as a result of our contractual obligations to Roche, we will be required to significantly scale up our active pharmaceutical ingredient production during the next few years. We do not currently have a significant inventory of the active pharmaceutical ingredient used in our products and product candidates, so if Avid does not maintain its status as an FDA-approved manufacturing facility, is unable to successfully scale up our active pharmaceutical ingredient production, or is unable to manufacture the active pharmaceutical ingredient used in our products and product candidates according to product specifications for any other reason, the commercialization of our products and the development of our product candidates will be delayed and our business will be adversely affected. We have entered into discussions to establish arrangements with an additional manufacturer for these ingredients. We have not yet established, and may not be able to establish, favorable arrangements with additional manufacturers for these ingredients or products should the existing supplies become unavailable or in the event that our sole contract manufacturer is unable to adequately perform its responsibilities. Any delays

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or interruptions in the supply of materials by Avid could cause the delay of clinical trials and could delay or prevent the commercialization of product candidates that may receive regulatory approval. Such delays or interruptions would have a material adverse effect on our business and financial condition.
If we have problems with the third parties that prepare, fill, finish, and package our product candidates for distribution, our product development and commercialization efforts for these candidates could be delayed or stopped.
     In the event that any of our product candidates are used in clinical trials or receive the necessary regulatory approval for commercialization, we rely on third parties to prepare, fill, finish, and package the products prior to their distribution. If we are unable to locate third parties to perform these functions on terms that are economically acceptable to us, the progress of clinical trials could be delayed or even suspended and the commercialization of approved product candidates could be delayed or prevented. We currently utilize a third-party to prepare, fill, finish, and package Cumulase. This third party has only limited experience manufacturing Cumulase batches and, to date, has not demonstrated a consistent ability to manufacture Cumulase according to product specifications. We have entered into an agreement with another third party to prepare, fill, finish and package Cumulase. We are currently in the technology transfer stage with this third party and expect to initiate commercial manufacturing in 2009. If our third party manufacturers are unable to successfully manufacture Cumulase, we may be unable to supply enough Cumulase product to meet demand. In addition, we currently utilize a subsidiary of Baxter to prepare, fill, finish, and package HYLENEX under a development and supply agreement. Baxter has only limited experience manufacturing HYLENEX batches, and we rely on its ability to successfully manufacture HYLENEX batches according to product specifications. Any delays or interruptions in Baxter’s ability to manufacture HYLENEX batches in amounts necessary to meet product demand could have a material adverse impact on our business and financial condition.
We may wish to raise funds in the next twelve months, and there can be no assurance that such funds will be available.
     During the next twelve months, we may wish to raise additional capital to complete or accelerate the steps required to continue development of our product candidates and to fund general operations. If we engage in acquisitions of companies, products, or technology in order to execute our business strategy, we may need to raise additional capital. We may be required to raise additional capital in the future through the public offering of securities, collaborative agreements, private financings and various other equity or debt financings, including calling outstanding warrants to purchase our common stock.
     Currently, warrants to purchase approximately 4.1 million shares of our common stock are outstanding and this amount of outstanding warrants may make us a less desirable candidate for investment for some potential investors. Approximately 1.4 million of our outstanding warrants contain a call feature that, potentially, may allow us to raise funds from the holders of these warrants. We have the ability, at our sole discretion, to call warrants exercisable for up to approximately 1.4 million shares of common stock and, upon such a call, the holders of these warrants have thirty days to decide whether to exercise their warrants at a price of $1.75 per share or receive $0.01 from us for each share of common stock that is not exercised.
     Considering our stage of development and the nature of our capital structure, if we are required to raise additional capital in the future, the additional financing may not be available on favorable terms, or at all. If we are successful in raising additional capital, a substantial number of additional shares may be issued and these shares will dilute the ownership interest of our current investors.
If our product candidates are approved by the FDA but do not gain market acceptance, our business will suffer because we may not be able to fund future operations.
     Assuming that we obtain the necessary regulatory approvals, a number of factors may affect the market acceptance of any of our existing product candidates or any other products we develop or acquire in the future, including, among others:

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    the price of our products relative to other therapies for the same or similar treatments;
 
    the perception by patients, physicians and other members of the health care community of the effectiveness and safety of our products for their prescribed treatments;
 
    our ability to fund our sales and marketing efforts;
 
    the degree to which the use of our products is restricted by the product label approved by the FDA;
 
    the effectiveness of our sales and marketing efforts; and
 
    the introduction of generic competitors.
     If our products do not gain market acceptance, we may not be able to fund future operations, including the development or acquisition of new product candidates and/or our sales and marketing efforts for our approved products, which would cause our business to suffer.
     In addition, our ability to market and promote our product candidates will be restricted to the labels approved by the FDA. If the approved labels are restrictive, our sales and marketing efforts may be negatively affected.
Developing and marketing pharmaceutical products for human use involves product liability risks, for which we currently have limited insurance coverage.
     The testing, marketing and sale of pharmaceutical products involves the risk of product liability claims by consumers and other third parties. Although we maintain product liability insurance coverage, product liability claims can be high in the pharmaceutical industry and our insurance may not sufficiently cover our actual liabilities. If product liability claims were made against us, it is possible that our insurance carriers may deny, or attempt to deny, coverage in certain instances. If a lawsuit against us is successful, then the lack or insufficiency of insurance coverage could materially and adversely affect our business and financial condition. Furthermore, various distributors of pharmaceutical products require minimum product liability insurance coverage before purchase or acceptance of products for distribution. Failure to satisfy these insurance requirements could impede our ability to achieve broad distribution of our proposed products and the imposition of higher insurance requirements could impose additional costs on us.
Our inability to attract, hire and retain key management and scientific personnel, and to recruit qualified independent directors, could negatively affect our business.
     Our success depends on the performance of key management and scientific employees with biotechnology experience. Given our small staff size and programs currently under development, we depend substantially on our ability to hire, train, retain and motivate high quality personnel, especially our scientists and management team in this field. If we are unable to retain existing personnel or identify or hire additional personnel, we may not be able to research, develop, commercialize or market our product candidates as expected or on a timely basis and, as a result, our business may be harmed. In addition, we rely on the expertise and guidance of independent directors to develop business strategies and to guide our execution of these strategies. Due to changes in the regulatory environment for public companies over the past few years, the demand for independent directors has increased and it may be difficult for us, due to competition from both like-size and larger companies, to recruit qualified independent directors.
     Furthermore, if we were to lose key management personnel, particularly Jonathan Lim, M.D., our president and chief executive officer, or Gregory Frost, Ph.D., our vice president and chief scientific officer, then we would likely lose some portion of our institutional knowledge and technical know-how, potentially causing a substantial delay in one or more of our development programs until adequate replacement personnel could be hired and trained. For example, Dr. Frost has been with us from soon after our inception, and he

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possesses a substantial amount of knowledge about our development efforts. If we were to lose his services, we would experience delays in meeting our product development schedules. We have not entered into any retention or other agreements specifically designed to motivate officers or other employees to remain with us, other than standard agreements relating to the vesting of stock options that every optionee of the Company must enter into as a condition of receiving an option grant.
     We do not have key man life insurance policies on the lives of any of our employees, including Dr. Lim and Dr. Frost.
Risks Related To Ownership of Our Common Stock
Future sales of shares of our common stock upon the exercise of currently outstanding securities or pursuant to our universal shelf registration statement may negatively affect our stock price.
     As a result of our January 2004 private financing transaction, we issued warrants to private investors for the purchase of approximately 10.5 million shares of common stock at purchase prices ranging from $0.77 to $1.75 per share. Currently, approximately 2.2 million shares of common stock remain issuable upon the exercise of these warrants. As a result of our October 2004 financing transaction, we issued warrants for the purchase of approximately 2.7 million shares of common stock at a purchase price of $2.25 per share. Currently, approximately 2.0 million shares of common stock remain issuable upon the exercise of these warrants. The exercise of these warrants could result in significant dilution to stockholders at the time of exercise which could negatively affect our stock price.
     We currently have the ability, from time to time, to offer and sell up to $32.5 million of additional equity or debt securities under a currently effective universal shelf registration statement. Sales of substantial amounts of shares of our common stock or other securities under our universal shelf registration statement could lower the market price of our common stock and impair our ability to raise capital through the sale of equity securities. In the future, we may issue additional options, warrants or other derivative securities convertible into our common stock.
Our stock price is subject to significant volatility.
     We participate in a highly dynamic industry which often results in significant volatility in the market price of common stock irrespective of company performance. As a result, our high and low sales prices of our common stock during the twelve months ended June 30, 2008 were $10.50 and $4.19, respectively. We expect our stock price to continue to be subject to significant volatility and, in addition to the other risks and uncertainties described elsewhere in this prospectus and all other risks and uncertainties that are either not known to us at this time or which we deem to be immaterial, any of the following factors may lead to a significant drop in our stock price:
    our failure, or the failure of one of our third party partners, to comply with the terms of our collaboration agreements;
 
    the termination, for any reason, of any of our collaboration agreements;
 
    the sale of common stock by any significant shareholder, including, but not limited to, direct or indirect sales by members of our Board of Directors;
 
    general negative conditions in the healthcare industry;
 
    general negative conditions in the financial markets;
 
    the failure, for any reason, to obtain FDA approval for any of our products;
 
    the failure, for any reason, to secure or defend our intellectual property position;

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    for those products that are approved by the FDA, the failure of the FDA to approve such products in a timely manner consistent with the FDA’s historical approval process;
 
    the suspension of our Chemophase clinical trial due to safety or patient tolerability issues;
 
    the suspension of our Chemophase clinical trial due to market and/or competitive conditions;
 
    our failure, or the failure of our third party partners, to successfully commercialize products approved by the FDA;
 
    our failure, or the failure of our third party partners, to generate product revenues anticipated by investors;
 
    problems with our sole API contract manufacturer or our sole fill and finish manufacturer for HYLENEX;
 
    the exercise of our right to redeem certain outstanding warrants to purchase our common stock;
 
    the sale of additional debt and/or equity securities by us; and
 
    the departure of key personnel.
Trading in our stock has historically been limited, so investors may not be able to sell as much stock as they want to at prevailing market prices.
     Our stock has historically traded at a low daily trading volume. If recent trading volumes decrease, it may be difficult for stockholders to sell their shares in the public market at any given time at prevailing prices.
Our decision to redeem outstanding warrants may drive down the market price of our stock.
     We may have the ability to redeem certain outstanding warrants, under certain conditions, that may be exercised for approximately 1.4 million shares of common stock. The redemption price for these warrants is $0.01 per share, but the warrant holders have the opportunity to exercise their warrants prior to redemption at the price of $1.75 per share. If we decide to redeem any portion of our outstanding warrants in the future, some selling security holders may choose to sell outstanding shares of common stock in order to finance the exercise of the warrants prior to their redemption. This pattern of selling may result in a reduction of our common stock’s market price.
Risks Related To Our Industry
Compliance with the extensive government regulations to which we are subject is expensive and time consuming and may result in the delay or cancellation of product sales, introductions or modifications.
     Extensive industry regulation has had, and will continue to have, a significant impact on our business. All pharmaceutical companies, including ours, are subject to extensive, complex, costly and evolving regulation by the federal government, principally the FDA and, to a lesser extent, the U.S. Drug Enforcement Administration, or DEA, and foreign and state government agencies. The Federal Food, Drug and Cosmetic Act, the Controlled Substances Act and other domestic and foreign statutes and regulations govern or influence the testing, manufacturing, packaging, labeling, storing, recordkeeping, safety, approval, advertising, promotion, sale and distribution of our products. Under certain of these regulations, we and our contract suppliers and manufacturers are subject to periodic inspection of our or their respective facilities, procedures and operations and/or the testing of products by the FDA, the DEA and other authorities, which conduct periodic inspections to confirm that we and our contract suppliers and manufacturers are in compliance with all applicable regulations. The FDA also conducts pre-approval and post-approval reviews and plant inspections to determine whether our systems, or our contract suppliers’ and manufacturers’ processes, are in

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compliance with cGMP and other FDA regulations. If we, or our contract supplier, fail these inspections, we may not be able to commercialize our product in a timely manner without incurring significant additional costs, or at all.
     In addition, the FDA imposes a number of complex regulatory requirements on entities that advertise and promote pharmaceuticals including, but not limited to, standards and regulations for direct-to-consumer advertising, off-label promotion, industry-sponsored scientific and educational activities, and promotional activities involving the internet.
     We are dependent on receiving FDA and other governmental approvals prior to manufacturing, marketing and shipping our products. Consequently, there is always a risk that the FDA or other applicable governmental authorities will not approve our products, or will take post-approval action limiting or revoking our ability to sell our products, or that the rate, timing and cost of such approvals will adversely affect our product introduction plans or results of operations.
Our suppliers and sole manufacturer are subject to regulation by the FDA and other agencies, and if they do not meet their commitments, we would have to find substitute suppliers or manufacturers, which could delay the supply of our products to market.
     Regulatory requirements applicable to pharmaceutical products make the substitution of suppliers and manufacturers costly and time consuming. We have no internal manufacturing capabilities and are, and expect to be in the future, entirely dependent on contract manufacturers and suppliers for the manufacture of our products and for their active and other ingredients. The disqualification of these manufacturers and suppliers through their failure to comply with regulatory requirements could negatively impact our business because the delays and costs in obtaining and qualifying alternate suppliers (if such alternative suppliers are available, which we cannot assure) could delay clinical trials or otherwise inhibit our ability to bring approved products to market, which would have a material adverse effect on our business and financial condition.
We may be required to initiate or defend against legal proceedings related to intellectual property rights, which may result in substantial expense, delay and/or cessation of the development and commercialization of our products.
     We rely on patents to protect our intellectual property rights. The strength of this protection, however, is uncertain. For example, it is not certain that:
    our patents and pending patent applications cover products and/or technology that we invented first;
 
    we were the first to file patent applications for these inventions;
 
    others will not independently develop similar or alternative technologies or duplicate our technologies;
 
    any of our pending patent applications will result in issued patents; and
 
    any of our issued patents, or patent pending applications that result in issued patents, will be held valid and infringed in the event the patents are asserted against others.
     We currently own or license several U.S. patents and also have pending patent applications. There can be no assurance that our existing patents, or any patents issued to us as a result of our pending patent applications, will provide a basis for commercially viable products, will provide us with any competitive advantages, or will not face third party challenges or be the subject of further proceedings limiting their scope or enforceability. Such limitations in our patent portfolio could have a material adverse effect on our business and financial condition. In addition, if any of our pending patent applications do not result in issued patents, this could have a material adverse effect on our business and financial condition.

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     We may become involved in interference proceedings in the U.S. Patent and Trademark Office to determine the priority of our inventions. In addition, costly litigation could be necessary to protect our patent position. We also rely on trademarks to protect the names of our products. These trademarks may be challenged by others. If we enforce our trademarks against third parties, such enforcement proceedings may be expensive. We also rely on trade secrets, unpatented proprietary know-how and continuing technological innovation that we seek to protect with confidentiality agreements with employees, consultants and others with whom we discuss our business. Disputes may arise concerning the ownership of intellectual property or the applicability or enforceability of these agreements, and we might not be able to resolve these disputes in our favor.
     In addition to protecting our own intellectual property rights, third parties may assert patent, trademark or copyright infringement or other intellectual property claims against us based on what they believe are their own intellectual property rights. If we become involved in any intellectual property litigation, we may be required to pay substantial damages, including but not limited to treble damages, for past infringement if it is ultimately determined that our products infringe a third party’s intellectual property rights. Even if infringement claims against us are without merit, defending a lawsuit takes significant time, may be expensive and may divert management’s attention from other business concerns. Further, we may be stopped from developing, manufacturing or selling our products until we obtain a license from the owner of the relevant technology or other intellectual property rights. If such a license is available at all, it may require us to pay substantial royalties or other fees.
Future acquisitions could disrupt our business and harm our financial condition.
     In order to augment our product pipeline or otherwise strengthen our business, we may decide to acquire additional businesses, products and technologies. As we have limited experience in evaluating and completing acquisitions, our ability as an organization to make such acquisitions is unproven. Acquisitions could require significant capital infusions and could involve many risks, including, but not limited to, the following:
    we may have to issue convertible debt or equity securities to complete an acquisition, which would dilute our stockholders and could adversely affect the market price of our common stock;
 
    an acquisition may negatively impact our results of operations because it may require us to incur large one-time charges to earnings, amortize or write down amounts related to goodwill and other intangible assets, or incur or assume substantial debt or liabilities, or it may cause adverse tax consequences, substantial depreciation or deferred compensation charges;
 
    we may encounter difficulties in assimilating and integrating the business, products, technologies, personnel or operations of companies that we acquire;
 
    certain acquisitions may disrupt our relationship with existing customers who are competitive with the acquired business, products or technologies;
 
    acquisitions may require significant capital infusions and the acquired businesses, products or technologies may not generate sufficient revenue to offset acquisition costs;
 
    an acquisition may disrupt our ongoing business, divert resources, increase our expenses and distract our management;
 
    acquisitions may involve the entry into a geographic or business market in which we have little or no prior experience; and
 
    key personnel of an acquired company may decide not to work for us.

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     If any of these risks occurred, it could adversely affect our business, financial condition and operating results. We cannot assure you that we will be able to identify or consummate any future acquisitions on acceptable terms, or at all. If we do pursue any acquisitions, it is possible that we may not realize the anticipated benefits from such acquisitions or that the market will not view such acquisitions positively.
If third party reimbursement and customer contracts are not available, our products may not be accepted in the market.
     Our ability to earn sufficient returns on our products will depend in part on the extent to which reimbursement for our products and related treatments will be available from government health administration authorities, private health insurers, managed care organizations and other healthcare providers.
     Third-party payors are increasingly attempting to limit both the coverage and the level of reimbursement of new drug products to contain costs. Consequently, significant uncertainty exists as to the reimbursement status of newly approved healthcare products. Third party payors may not establish adequate levels of reimbursement for the products that we commercialize, which could limit their market acceptance and result in a material adverse effect on our financial condition.
     Customer contracts, such as with group paying organizations and hospital formularies, will often not offer contract or formulary status without either the lowest price or substantial proven clinical differentiation. If our products are compared to animal-derived hyaluronidases by these entities, it is possible that neither of these conditions will be met, which could limit market acceptance and result in a material adverse effect on our financial condition.
The rising cost of healthcare and related pharmaceutical product pricing has led to cost containment pressures that could cause us to sell our products at lower prices, resulting in less revenue to us.
     Any of our products that have been or in the future are approved by the FDA may be purchased or reimbursed by state and federal government authorities, private health insurers and other organizations, such as health maintenance organizations and managed care organizations. Such third party payors increasingly challenge pharmaceutical product pricing. The trend toward managed healthcare in the United States, the growth of such organizations, and various legislative proposals and enactments to reform healthcare and government insurance programs, including the Medicare Prescription Drug Modernization Act of 2003, could significantly influence the manner in which pharmaceutical products are prescribed and purchased, resulting in lower prices and/or a reduction in demand. Such cost containment measures and healthcare reforms could adversely affect our ability to sell our products. Furthermore, individual states have become increasingly aggressive in passing legislation and implementing regulations designed to control pharmaceutical product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access, importation from other countries and bulk purchasing. Legally mandated price controls on payment amounts by third party payors or other restrictions could negatively and materially impact our revenues and financial condition. We anticipate that we will encounter similar regulatory and legislative issues in most other countries outside the United States.
We face intense competition and rapid technological change that could result in the development of products by others that are superior to the products we are developing.
     We have numerous competitors in the United States and abroad including, among others, major pharmaceutical and specialized biotechnology firms, universities and other research institutions that may be developing competing products. Such competitors include, but are not limited to, Sigma-Aldrich Corporation, ISTA, Amphastar and Primapharm among others. These competitors may develop technologies and products that are more effective, safer, or less costly than our current or future product candidates or that could render our technologies and product candidates obsolete or noncompetitive. Many of these competitors have substantially more resources and product development, manufacturing and marketing experience and capabilities than we do. In addition, many of our competitors have significantly greater experience than we do in undertaking pre-clinical testing and clinical trials of pharmaceutical product candidates and obtaining FDA and other regulatory approvals of products and therapies for use in healthcare. Other manufacturers have FDA

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approved products for use as spreading agents, including ISTA, with an ovine-derived hyaluronidase, Vitrase, Amphastar, with a bovine-derived hyaluronidase, Amphadase, and Primapharm, also with a bovine-derived hyaluronidase, Hydase. The FDA has determined that Amphadase, Hydase, HYLENEX and Vitrase are distinct new chemical entities and hence afforded five years of market exclusivity. The five year market exclusivity precludes identical new chemical entity products from being marketed for a period of five years. As each of these products is established as distinctly different new chemical entities, the marketing exclusivity granted does not prohibit the marketing of the products.

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RATIO OF EARNINGS TO FIXED CHARGES
     The following table sets forth ratios of earnings to fixed charges for the periods shown.
                                 
Twelve Months Ended December 31,
2007   2006   2005   2004   2003
N/A
    N/A       N/A       N/A       N/A  
     The ratio of earnings to fixed charges was computed by dividing earnings by fixed charges. For this purpose, earnings consist of net loss before fixed charges. Fixed charges consist of interest expense plus the interest factor in lease expenses. During the fiscal years covered by this table, we did not have any material fixed charges or preferred stock dividends. However, our total lease expenses, which comprised most of our total commitments, were $1,050,000, $297,000, $238,000, $148,000 and $123,000 for the twelve months ended December 31, 2007, 2006, 2005, 2004 and 2003.
     Earnings have been inadequate to cover fixed charges and total commitments. The dollar amount of the coverage deficiency was approximately $23.9 million, $14.8 million, $13.3 million, $9.1 million and $2.1 million for the twelve months ended December 31, 2007, 2006, 2005, 2004 and 2003.

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USE OF PROCEEDS
     Unless otherwise provided in a supplement or amendment to this prospectus, we intend to use any net proceeds from this offering, together with other available funds, for operating costs, capital expenditures and working capital needs and for other general corporate purposes.
     We have not specifically identified the precise amounts we will spend on each of these areas or the timing of these expenditures. The amounts actually expended for each purpose may vary significantly depending upon numerous factors, including the amount and timing of the proceeds from this offering, progress with clinical product development and other research programs. In addition, expenditures may also depend on the establishment of new collaborative arrangements with other companies, the availability of additional financing, and other factors.
     We anticipate that we will be required to raise substantial additional capital to continue to fund the clinical development of our technologies and products. We may raise additional capital through additional public or private financing, as well as collaborative relationships, incurring debt and other available sources.

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WHERE YOU CAN FIND MORE INFORMATION
     We file annual, quarterly and special reports, proxy statements and other information with the SEC. You may read and copy any document we file at the SEC’s public reference rooms located at Room 1024, 450 Fifth Street, N.W., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the public reference rooms. We are also required to file electronic versions of these documents with the SEC, which may be accessed from the SEC’s Internet site at http://www.sec.gov or at our website http://www.halozyme.com.
     The SEC allows us to “incorporate by reference” the information we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus, and information that we file with the SEC later will automatically update and supersede the information in this prospectus or incorporated by reference. The following documents filed by us and any future filings made by us with the SEC under Sections 13(a), 13(c) 14 or 15(d) of the Securities Exchange Act of 1934, until we sell all of the securities offered hereby, are incorporated by reference in this prospectus:
  1.   Our Annual Report on Form 10-K for the year ended December 31, 2007, filed with the SEC on March 14, 2008.
 
  2.   Our Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2008, filed with the SEC on May 9, 2008.
 
  3.   Our Quarterly Report on Form 10-Q for the fiscal quarter ended June 30, 2008, filed with the SEC on August 8, 2008.
 
  4.   Our Current Reports on Form 8-K filed with SEC on February 8, 2008; March 19, 2008; April 21, 2008; and August 21, 2008.
 
  5.   Our definitive Proxy Statement on Schedule 14A, including a description of the differences between the rights of holders of Halozyme Nevada common stock and Halozyme Delaware common stock, filed with the SEC on October 11, 2007.
 
  6.   All of the filings pursuant to the Securities Exchange Act that we may make prior to the effectiveness of this registration statement, and prior to the termination of the offering contemplated by this prospectus.
     We will furnish without charge to you, on written or oral request, a copy of any or all of the documents incorporated by reference. You should direct any requests for documents to David Ramsay, Chief Financial Officer, 11388 Sorrento Valley Road, San Diego, California 92121, telephone: (858) 794-8889.

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THE SECURITIES WE MAY OFFER
     The descriptions of the securities contained in this prospectus, together with the applicable prospectus supplements, summarize all the material terms and provisions of the various types of securities that we may offer. We will describe in the applicable prospectus supplement the particular terms of the securities offered by that prospectus supplement. If we indicate in the applicable prospectus supplement, the terms of the securities may differ from the terms we have summarized below. We will also include in the prospectus supplement information, where applicable, about material U.S. federal income tax considerations relating to the securities, and the securities exchange, if any, on which the securities will be listed.
DESCRIPTION OF COMMON STOCK
     The following is only a summary of the material terms of our common stock and, because it is only a summary, it does not contain all the information that may be important to you. Accordingly, you should read carefully the more detailed provisions of our certificate of incorporation and bylaws, each of which has been filed with the SEC, as well as applicable Delaware law.
General
     We currently have authorized 150,000,000 shares of common stock, par value $0.001, and, as of September 1, 2008, we had 80,497,114 shares of common stock outstanding. As of September 1, 2008, we had an aggregate of 18,225,000 shares of common stock reserved for issuance upon exercise of stock options granted, or to be granted, under our 2001 Amended and Restated Stock Plan, 2004 Stock Plan, 2005 Outside Directors’ Stock Plan and 2006 Stock Plan. As of September 1, 2008, we had warrants to purchase an aggregate of approximately 4,202,619 shares of our common stock outstanding.
Voting Rights
     Holders of our common stock are entitled to one vote per share on all matters to be voted upon by the stockholders. The holders of common stock are not entitled to cumulate voting rights with respect to the election of directors, which means that the holders of a majority of the shares voted can elect all of the directors then standing for election.
Dividends
     Subject to limitations under Delaware law and preferences that may apply to any outstanding shares of preferred stock, holders of our common stock are entitled to receive ratably such dividends or other distribution, if any, as may be declared by our board of directors out of funds legally available therefor.
Liquidation
     In the event of our liquidation, dissolution or winding up, holders of our common stock are entitled to share ratably in all assets remaining after payment of liabilities, subject to the liquidation preference of any outstanding preferred stock.
Rights and Preferences
     The common stock has no preemptive, conversion or other rights to subscribe for additional securities. There are no redemption or sinking fund provisions applicable to our common stock. The rights, preferences and privileges of holders of common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that we may designate and issue in the future.

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Fully Paid and Nonassessable
     All outstanding shares of our common stock are, and all shares of common stock to be outstanding upon completion of the offering will be, validly issued, fully paid and nonassessable.
Transfer Agent and Registrar
     The transfer agent and registrar for our common stock is Corporate Stock Transfer Company.
DESCRIPTION OF PREFERRED STOCK
     We currently have authorized 20,000,000 shares of preferred stock, $0.001 par value per share, of which 500,000 shares have been designated Series A Preferred Stock and the rest of the shares of preferred stock are undesignated. As of the date of this prospectus, we did not have any shares of preferred stock outstanding.
     Our Board of Directors is authorized to fix and determine designations, preferences, privileges, rights, and powers and relative, participating, optional, or other special rights, qualifications, limitations, or restrictions on our preferred stock as provided by the Delaware General Corporation Law.
     The purpose of authorizing our Board of Directors to issue preferred stock in one or more series and determine the number of shares in the series and its rights and preferences is to eliminate delays associated with a stockholder vote on specific issuances. Examples of rights and preferences that the Board of Directors may fix are: (1) dividend rights, (2) dividend rates, (3) conversion rights, (4) voting rights, (5) terms of redemption, and (6) liquidation preferences. The issuance of preferred stock, while providing desirable flexibility in connection with possible acquisitions and other corporate purposes, could make it more difficult for a third party to acquire, or could discourage a third party from acquiring, a majority of our outstanding voting stock. The rights of holders of our common stock described above, will be subject to, and may be adversely affected by, the rights of any preferred stock that we may designate and issue in the future.
     We will incorporate by reference as an exhibit to the registration statement which includes this prospectus the form of any certificate of designation which describes the terms of the series of preferred stock we are offering. This description and the applicable prospectus supplement will include:
    the title and stated value;
 
    the number of shares authorized;
 
    the liquidation preference per share;
 
    the purchase price;
 
    the dividend rate, period and payment date, and method of calculation for dividends;
 
    whether dividends will be cumulative or non-cumulative and, if cumulative, the date from which dividends will accumulate;
 
    the procedures for any auction and remarketing, if any;
 
    the provisions for a sinking fund, if any;
 
    the provisions for redemption or repurchase, if applicable, and any restrictions on our ability to exercise those redemption and repurchase rights;

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    any listing of the preferred stock on any securities exchange or market;
 
    whether the preferred stock will be convertible into our common stock, and, if applicable, the conversion price, or how it will be calculated, and the conversion period;
 
    whether the preferred stock will be exchangeable into debt securities, and, if applicable, the exchange price, or how it will be calculated, and the exchange period;
 
    voting rights, if any, of the preferred stock;
 
    preemptive rights, if any;
 
    restrictions on transfer, sale or other assignment, if any;
 
    whether interests in the preferred stock will be represented by depositary shares;
 
    a discussion of any material U.S. federal income tax considerations applicable to the preferred stock;
 
    the relative ranking and preferences of the preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs;
 
    any limitations on issuance of any class or series of preferred stock ranking senior to or on a parity with the series of preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs; and
 
    any other specific terms, preferences, rights or limitations of, or restrictions on, the preferred stock.
     If we issue shares of preferred stock under this prospectus, the shares will be fully paid and nonassessable and will not have, or be subject to, any preemptive or similar rights.
     The transfer agent and registrar for any series of preferred stock will be set forth in the applicable prospectus supplement.
DESCRIPTION OF DEBT SECURITIES
     The following description, together with the additional information we include in any applicable prospectus supplements, summarizes the material terms and provisions of the debt securities that we may offer under this prospectus. While the terms we have summarized below will apply generally to any future debt securities we may offer, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. If we indicate in a prospectus supplement, the terms of any debt securities we offer under that prospectus supplement may differ from the terms we describe below.
     We will issue any senior notes under the senior indenture which we will enter into with a trustee to be named in the senior indenture. We will issue any subordinated notes under the subordinated indenture which we will enter into with a trustee to be named in the subordinated indenture. We have filed forms of these documents as exhibits to the registration statement which includes this prospectus. We use the term “indentures” to refer to both the senior indenture and the subordinated indenture. The indentures will be qualified under the Trust Indenture Act of 1939. We use the term “debenture trustee” to refer to either the senior trustee or the subordinated trustee, as applicable.
     The following summaries of material provisions of the senior notes, the subordinated notes and the indentures are subject to, and qualified in their entirety by reference to, all the provisions of the indenture

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applicable to a particular series of debt securities. Except as we may otherwise indicate, the terms of the senior indenture and the subordinated indenture are identical.
     We conduct some of our operations through a subsidiary formed under the laws of California. Our rights and the rights of our creditors, including holders of debt securities, to the assets of any subsidiary of ours upon that subsidiary’s liquidation or reorganization or otherwise would be subject to the prior claims of that subsidiary’s creditors, except to the extent that we may be a creditor with recognized claims against the subsidiary. Our subsidiary’s creditors would include trade creditors, debt holders, secured creditors and taxing authorities. Except as we may provide in a prospectus supplement, neither the debt securities nor the indentures restrict us or our subsidiary from incurring indebtedness.
General
     We will describe in each prospectus supplement the following terms relating to a series of notes:
    the title;
 
    any limit on the amount that may be issued;
 
    whether or not we will issue the series of notes in global form, the terms and who the depository will be;
 
    the maturity date;
 
    the annual interest rate, which may be fixed or variable, or the method for determining the rate;
 
    the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;
 
    whether or not the notes will be secured or unsecured, and the terms of any security;
 
    the terms of the subordination of any series of subordinated debt;
 
    the place where payments will be payable;
 
    our right, if any, to defer payment of interest and the maximum length of any such deferral period;
 
    the date, if any, after which, and the price at which, we may, at our option, redeem the series of notes pursuant to any optional redemption provisions;
 
    the date, if any, on which, and the price at which we are obligated, pursuant to any mandatory sinking fund provisions or otherwise, to redeem, or at the holder’s option to purchase, all or a portion of the series of notes;
 
    whether the indenture will restrict our ability to pay dividends, or will require us to maintain any asset ratios or reserves;
 
    whether we will be restricted from incurring any additional indebtedness;
 
    a discussion of any material United States federal income tax considerations applicable to the notes;

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    the denominations in which we will issue the series of notes, if other than denominations of $1,000 and any integral multiple thereof; and
 
    any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities.
Conversion or Exchange Rights
     We will set forth in the prospectus supplement the terms on which a series of notes may be convertible into or exchangeable for common stock or other securities of ours. We will include in that prospectus supplement provisions as to whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of common stock or other securities of ours that the holders of the series of notes receive would be subject to adjustment.
Consolidation, Merger or Sale of Assets
     The indentures do not contain any covenant which restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of all or substantially all of our assets. However, any successor to or acquirer of such assets must assume all of our obligations under the indentures or the notes, as appropriate.
Events of Default Under the Indenture
     The following are events of default under the indentures with respect to any series of notes that we may issue:
    if we fail to pay interest when due and our failure continues for 60 days and the time for payment has not been extended or deferred;
 
    if we fail to pay the principal, or premium, if any, when due and the time for payment has not been extended or delayed;
 
    if we fail to observe or perform any other covenant contained in the notes or the indentures, other than a covenant specifically relating to another series of notes, and our failure continues for 60 days after we receive notice from the debenture trustee or holders of at least 50% in aggregate principal amount of the outstanding notes of the applicable series; and
 
    if specified events of bankruptcy, insolvency or reorganization occur as to us.
     If an event of default with respect to notes of any series occurs and is continuing, the debenture trustee or the holders of at least 50% in aggregate principal amount of the outstanding notes of that series, by notice to us in writing, and to the debenture trustee if notice is given by such holders, may declare the unpaid principal of, premium, if any, and accrued interest, if any, due and payable immediately.
     The holders of a majority in principal amount of the outstanding notes of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.
     Subject to the terms of the indentures, if an event of default under an indenture shall occur and be continuing, the debenture trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of notes, unless such holders have offered the debenture trustee reasonable indemnity. The holders of a majority in principal amount of the outstanding notes of any series will have the right to direct the time, method and place of conducting any

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proceeding for any remedy available to the debenture trustee, or exercising any trust or power conferred on the debenture trustee, with respect to the notes of that series, provided that:
    the direction so given by the holder is not in conflict with any law or the applicable indenture; and
 
    subject to its duties under the Trust Indenture Act, the debenture trustee need not take any action that might involve it in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.
     A holder of the notes of any series will only have the right to institute a proceeding under the indentures or to appoint a receiver or trustee, or to seek other remedies if:
    the holder has given written notice to the debenture trustee of a continuing event of default with respect to that series;
 
    the holders of at least 50% in aggregate principal amount of the outstanding notes of that series have made written request, and such holders have offered reasonable indemnity to the debenture trustee to institute the proceeding as trustee; and
 
    the debenture trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate principal amount of the outstanding notes of that series other conflicting directions within 60 days after the notice, request and offer.
     These limitations do not apply to a suit instituted by a holder of notes if we default in the payment of the principal, premium, if any, or interest on, the notes.
     We will periodically file statements with the debenture trustee regarding our compliance with specified covenants in the indentures.
Modification of Indenture; Waiver
     We and the debenture trustee may change an indenture without the consent of any holders with respect to specific matters, including:
    to fix any ambiguity, defect or inconsistency in the indenture; and
 
    to change anything that does not materially adversely affect the interests of any holder of notes of any series.
     In addition, under the indentures, the rights of holders of a series of notes may be changed by us and the debenture trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding notes of each series that is affected. However, we and the debenture trustee may only make the following changes with the consent of each holder of any outstanding notes affected:
    extending the fixed maturity of the series of notes;
 
    reducing the principal amount, reducing the rate of or extending the time of payment of interest, or any premium payable upon the redemption of any notes; or
 
    reducing the percentage of notes, the holders of which are required to consent to any amendment.

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Discharge
     Each indenture provides that we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for obligations to:
    register the transfer or exchange of debt securities of the series;
 
    replace stolen, lost or mutilated debt securities of the series;
 
    maintain paying agencies;
 
    hold monies for payment in trust;
 
    compensate and indemnify the trustee; and
 
    appoint any successor trustee.
     In order to exercise our rights to be discharged, we must deposit with the debenture trustee money or government obligations sufficient to pay all the principal of, any premium, if any, and interest on, the debt securities of the series on the dates payments are due.
Form, Exchange, and Transfer
     We will issue the notes of each series only in fully registered form without coupons and, unless we otherwise specify in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple thereof. The indentures provide that we may issue notes of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company or another depository named by us and identified in a prospectus supplement with respect to that series. See “Legal Ownership of Securities” for a further description of the terms relating to any book-entry securities.
     At the option of the holder, subject to the terms of the indentures and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the notes of any series can exchange the notes for other notes of the same series, in any authorized denomination and of like tenor and aggregate principal amount.
     Subject to the terms of the indentures and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the notes may present the notes for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the notes that the holder presents for transfer or exchange, we will make no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.
     We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any notes. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the notes of each series.
     If we elect to redeem the notes of any series, we will not be required to:
    issue, register the transfer of, or exchange any notes of that series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any notes that may be selected for redemption and ending at the close of business on the day of the mailing; or

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    register the transfer of or exchange any notes so selected for redemption, in whole or in part, except the unredeemed portion of any notes we are redeeming in part.
Information Concerning the Debenture Trustee
     The debenture trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the debenture trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the debenture trustee is under no obligation to exercise any of the powers given it by the indentures at the request of any holder of notes unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.
Payment and Paying Agents
     Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any notes on any interest payment date to the person in whose name the notes, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.
     We will pay principal of and any premium and interest on the notes of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, will we make interest payments by check which we will mail to the holder. Unless we otherwise indicate in a prospectus supplement, we will designate the corporate trust office of the debenture trustee in the City of New York as our sole paying agent for payments with respect to notes of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the notes of a particular series. We will maintain a paying agent in each place of payment for the notes of a particular series.
     All money we pay to a paying agent or the debenture trustee for the payment of the principal of or any premium or interest on any notes which remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the security thereafter may look only to us for payment of those amounts.
Governing Law
     The indentures and the notes will be governed by and construed in accordance with the laws of the State of New York, except to the extent that the Trust Indenture Act is applicable.
Subordination of Subordinated Notes
     The subordinated notes will be unsecured and will be subordinate and junior in priority of payment to some or all of our other indebtedness to the extent described in a prospectus supplement. The subordinated indenture does not limit the amount of subordinated notes which we may issue. It also does not limit us from issuing any other secured or unsecured debt.
DESCRIPTION OF WARRANTS
     The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the warrants that we may offer under this prospectus and the related warrant agreements and warrant certificates. While the terms summarized below will apply generally to any warrants that we may offer, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any warrants offered under that prospectus supplement may differ from the terms described below. Specific warrant agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement which includes this prospectus.

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General
     We may issue warrants for the purchase of common stock, preferred stock and/or debt securities in one or more series. We may issue warrants independently or together with common stock, preferred stock and/or debt securities, and the warrants may be attached to or separate from these securities.
     We will evidence each series of warrants by warrant certificates that we will issue under a separate warrant agreement. We will enter into the warrant agreement with a warrant agent. Each warrant agent will be a bank that we select which has its principal office in the United States and a combined capital and surplus of at least $50,000,000. We will indicate the name and address of the warrant agent in the applicable prospectus supplement relating to a particular series of warrants.
     We will describe in the applicable prospectus supplement the terms of the series of warrants, including:
    the offering price and aggregate number of warrants offered;
 
    the currency for which the warrants may be purchased;
 
    if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;
 
    if applicable, the date on and after which the warrants and the related securities will be separately transferable;
 
    in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at, and currency in which, this principal amount of debt securities may be purchased upon such exercise;
 
    in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which these shares may be purchased upon such exercise;
 
    the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreement and the warrants;
 
    the terms of any rights to redeem or call the warrants;
 
    any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;
 
    the dates on which the right to exercise the warrants will commence and expire;
 
    the manner in which the warrant agreement and warrants may be modified;
 
    federal income tax consequences of holding or exercising the warrants;
 
    the terms of the securities issuable upon exercise of the warrants; and
 
    any other specific terms, preferences, rights or limitations of or restrictions on the warrants.
     Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:

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    in the case of warrants to purchase debt securities, the right to receive payments of principal of, or any premium or interest on, the debt securities purchasable upon exercise or to enforce covenants in the applicable indenture; or
 
    in the case of warrants to purchase common stock or preferred stock, the right to receive any dividends or payments upon our liquidation, dissolution or winding up or to exercise any voting rights.
Exercise of Warrants
     Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to 5:00 P.M. New York time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.
     Holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent upon exercise.
     Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.
Enforceability of Rights By Holders of Warrants
     Each warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue or series of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.
LEGAL OWNERSHIP OF SECURITIES
     We can issue securities in registered form or in the form of one or more global securities. We describe global securities in greater detail below. We refer to those persons who have securities registered in their own names on the books that we or any applicable trustee maintain for this purpose as the “holders” of those securities. These persons are the legal holders of the securities. We refer to those persons who, indirectly through others, own beneficial interests in securities that are not registered in their own names, as “indirect holders” of those securities. As we discuss below, indirect holders are not legal holders, and investors in securities issued in book-entry form or in street name will be indirect holders.

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Book-Entry Holders
     We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary’s book-entry system. These participating institutions, which are referred to as participants, in turn, hold beneficial interests in the securities on behalf of themselves or their customers.
     Only the person in whose name a security is registered is recognized as the holder of that security. Securities issued in global form will be registered in the name of the depositary or its participants. Consequently, for securities issued in global form, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which in turn pass the payments along to their customers who are the beneficial owners. The depositary and its participants do so under agreements they have made with one another or with their customers; they are not obligated to do so under the terms of the securities.
     As a result, investors in a book-entry security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker or other financial institution that participates in the depositary’s book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not holders, of the securities.
Street Name Holders
     We may terminate a global security or issue securities in non-global form. In these cases, investors may choose to hold their securities in their own names or in “street name.” Securities held by an investor in street name would be registered in the name of a bank, broker or other financial institution that the investor chooses, and the investor would hold only a beneficial interest in those securities through an account he or she maintains at that institution.
     For securities held in street name, we will recognize only the banks, brokers and other financial institutions in whose names the securities are registered as the holders of those securities, and we will make all payments on those securities to them. These institutions pass along the payments they receive to their customers who are the beneficial owners, but only because they agree to do so in their customer agreements or because they are legally required to do so. Investors who hold securities in street name will be indirect holders, not holders, of those securities.
Legal Holders
     Our obligations, as well as the obligations of any applicable trustee and of any third parties employed by us or a trustee, run only to the holders of the securities. We do not have obligations to investors who hold beneficial interests in global securities, in street name or by any other indirect means. This will be the case whether an investor chooses to be an indirect holder of a security or has no choice because we are issuing the securities only in global form.
     For example, once we make a payment or give a notice to the holder, we have no further responsibility for the payment or notice even if that holder is required, under agreements with depositary participants or customers or by law, to pass the payment or notice along to the indirect holders but does not do so. Similarly, we may want to obtain the approval of the holders to amend an indenture, such as to relieve us of the consequences of a default or of our obligation to comply with a particular provision of the indenture or for other purposes. In such an event, we would seek approval only from the holders, and not the indirect holders, of the securities. Whether and how the holders contact the indirect holders is up to the holders.

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Special Considerations for Indirect Holders
     If you hold securities through a bank, broker or other financial institution, either in book-entry form or in street name, you should check with your own institution to find out:
    how it handles securities payments and notices;
 
    whether it imposes fees or charges;
 
    how it would handle a request for the holders’ consent, if ever required;
 
    whether and how you can instruct it to send you securities registered in your own name so you can be a holder, if that is permitted in the future;
 
    how it would exercise rights under the securities if there were a default or other event triggering the need for holders to act to protect their interests; and
 
    if the securities are in book-entry form, how the depositary’s rules and procedures will affect these matters.
Global Securities
     A global security is a security held by a depositary which represents one or more individual securities. Generally, all securities represented by the same global securities will have the same terms.
     Each security issued in book-entry form will be represented by a global security that we deposit with and register in the name of a financial institution or its nominee that we select. The financial institution that we select for this purpose is called the depositary. Unless we specify otherwise in the applicable prospectus supplement, The Depository Trust Company, New York, New York, known as DTC, will be the depositary for all securities issued in book-entry form.
     A global security may not be transferred to or registered in the name of anyone other than the depositary, its nominee or a successor depositary, unless special termination situations arise. We describe those situations below under the section titled “Special Situations When a Global Security Will Be Terminated.” As a result of these arrangements, the depositary, or its nominee, will be the sole registered owner and holder of all securities represented by a global security, and investors will be permitted to own only beneficial interests in a global security. Beneficial interests must be held by means of an account with a broker, bank or other financial institution that in turn has an account with the depositary or with another institution that does. Thus, an investor whose security is represented by a global security will not be a holder of the security, but only an indirect holder of a beneficial interest in the global security.
     If the prospectus supplement for a particular security indicates that the security will be issued in global form only, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.
Special Considerations for Global Securities
     As an indirect holder, an investor’s rights relating to a global security will be governed by the account rules of the investor’s financial institution and of the depositary, as well as general laws relating to securities transfers. We do not recognize an indirect holder as a holder of securities and instead deal only with the depositary that holds the global security.

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     If securities are issued only in the form of a global security, an investor should be aware of the following:
    An investor cannot cause the securities to be registered in his or her name, and cannot obtain non-global certificates for his or her interest in the securities, except in the special situations we describe below;
 
    An investor will be an indirect holder and must look to his or her own bank or broker for payments on the securities and protection of his or her legal rights relating to the securities, as we describe under this section;
 
    An investor may not be able to sell interests in the securities to some insurance companies and to other institutions that are required by law to own their securities in non-book-entry form;
 
    An investor may not be able to pledge his or her interest in a global security in circumstances where certificates representing the securities must be delivered to the lender or other beneficiary of the pledge in order for the pledge to be effective;
 
    The depositary’s policies, which may change from time to time, will govern payments, transfers, exchanges and other matters relating to an investor’s interest in a global security. We and any applicable trustee have no responsibility for any aspect of the depositary’s actions or for its records of ownership interests in a global security. We and the trustee also do not supervise the depositary in any way;
 
    The depositary may, and we understand that DTC will, require that those who purchase and sell interests in a global security within its book-entry system use immediately available funds, and your broker or bank may require you to do so as well; and
 
    Financial institutions that participate in the depositary’s book-entry system, and through which an investor holds its interest in a global security, may also have their own policies affecting payments, notices and other matters relating to the securities. There may be more than one financial intermediary in the chain of ownership for an investor. We do not monitor and are not responsible for the actions of any of those intermediaries.
Special Situations When a Global Security Will Be Terminated
     In a few special situations described below, the global security will terminate and interests in it will be exchanged for physical certificates representing those interests. After that exchange, the choice of whether to hold securities directly or in street name will be up to the investor. Investors must consult their own banks or brokers to find out how to have their interests in securities transferred to their own name, so that they will be direct holders. We have described the rights of holders and street name investors above.
     The global security will terminate when the following special situations occur:
    if the depositary notifies us that it is unwilling, unable or no longer qualified to continue as depositary for that global security and we do not appoint another institution to act as depositary within 90 days;
 
    if we notify any applicable trustee that we wish to terminate that global security; or
 
    if an event of default has occurred with regard to securities represented by that global security and has not been cured or waived.

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     The prospectus supplement may also list additional situations for terminating a global security that would apply only to the particular series of securities covered by the prospectus supplement. When a global security terminates, the depositary, and not we or any applicable trustee, is responsible for deciding the names of the institutions that will be the initial direct holders.
ADDITIONAL INFORMATION CONCERNING OUR CAPITAL STOCK
     Our bylaws provide that the Board of Directors is divided into three classes of directors, with each class serving a staggered three-year term. The classification system of electing directors may tend to discourage a third party from making a tender offer or otherwise attempting to obtain control of Halozyme and may maintain the incumbency of the Board of Directors, as it generally makes it more difficult for stockholders to replace a majority of the directors. Our Bylaws do not permit stockholders to act without a meeting and do not provide for cumulative voting in the election of directors.
     These and other provisions of our certificate of incorporation, including, but not limited to the Board of Directors’ ability to designate the rights and preferences of our preferred stock, could have the effect of deterring certain takeovers or delaying or preventing certain changes in control or management of Halozyme, including transactions in which stockholders might otherwise receive a premium for their shares over then-current market prices.

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PLAN OF DISTRIBUTION
     The securities being offered may be sold in one or more transactions at fixed prices, at prevailing market prices at the time of sale, at prices related to the prevailing market prices, at varying prices determined at the time of sale, or at negotiated prices. These sales may be effected at various times in one or more of the following transactions, or in other kinds of transactions:
    through underwriters for resale to the public or investors:
 
    transactions on the American Stock Exchange or on any national securities exchange or U.S. inter-dealer system of a registered national securities association on which our common stock may be listed or quoted at the time of sale;
 
    in the over-the-counter market;
 
    in private transactions and transactions otherwise than on these exchanges or systems or in the over-the-counter market;
 
    in connection with short sales of the shares;
 
    by pledge to secure debt and other obligations;
 
    through the writing of options, whether the options are listed on an options exchange or otherwise;
 
    in connection with the writing of non-traded and exchange-traded call options, in hedge transactions and in settlement of other transactions in standardized or over-the-counter options;
 
    through a combination of any of the above transactions; or
 
    any other method permitted by law.
     We may sell our securities directly to one or more purchasers, or to or through underwriters, dealers or agents or through a combination of those methods. The related prospectus supplement will set forth the terms of each offering, including:
    the name or names of any agents, dealers, underwriters or investors who purchase the securities;
 
    the purchase price of the securities being offered and the proceeds we will receive from the sale;
 
    the amount of any compensation, discounts commissions or fees to be received by the underwriters, dealer or agents;
 
    any over-allotment options under which underwriters may purchase additional securities from us;
 
    any discounts or concessions allowed or reallowed or paid to dealers;
 
    any securities exchanges on which such securities may be listed;

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    the terms of any indemnification provisions, including indemnification from liabilities under the federal securities laws; and
 
    the nature of any transaction by an underwriter, dealer or agent during the offering that is intended to stabilize or maintain the market price of the securities.
     In addition, any securities covered by this prospectus which qualify for sale pursuant to Regulation S of the Securities Act of 1933, as amended (the “Securities Act”), may be sold pursuant to Regulation S rather than pursuant to this prospectus.
     In connection with the sale of our common stock, underwriters may receive compensation from us or from purchasers of our common stock in the form of discounts, concessions or commissions. Underwriters, dealers and agents that participate in the distribution of our common stock may be deemed to be underwriters. Discounts or commissions they receive and any profit on their resale of our common stock may be considered underwriting discounts and commissions under the Securities Act.
     We may agree to indemnify underwriters, dealers and agents who participate in the distribution of our common stock against various liabilities, including liabilities under the Securities Act of 1933. We may also agree to contribute to payments which the underwriters, dealers or agents may be required to make in respect of these liabilities. We may authorize dealers or other persons who act as our agents to solicit offers by various institutions to purchase our common stock from us under contracts which provide for payment and delivery on a future date. We may enter into these contracts with commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and others. If we enter into these agreements concerning any series of our common stock, we will indicate that in the prospectus supplement or amendment.
     In connection with an offering of our common stock, underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of our common stock. Specifically, underwriters may over-allot in connection with the offering, creating a syndicate short position in our common stock for their own account. In addition, underwriters may bid for, and purchase, our common stock in the open market to cover short positions or to stabilize the price of our common stock. Finally, underwriters may reclaim selling concessions allowed for distributing our common stock in the offering if the underwriters repurchase previously distributed common stock in transactions to cover short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of our common stock above independent market levels. Underwriters are not required to engage in any of these activities and may end any of these activities at any time. Agents and underwriters may engage in transactions with, or perform services for, us and our affiliates in the ordinary course of business.

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LEGAL MATTERS
     The validity of the securities offered hereby and other legal matters relating to the offering will be passed upon for us by DLA Piper LLP (US), San Diego, California.
EXPERTS
     The consolidated financial statements of Halozyme Therapeutics, Inc. appearing in Halozyme Therapeutics, Inc.’s Annual Report (Form 10-K) as of and for the years ended December 31, 2007 and 2006, and the effectiveness of Halozyme Therapeutics, Inc.’s internal control over financial reporting as of December 31, 2007, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.
     The consolidated financial statements of Halozyme Therapeutics, Inc. as of December 31, 2005, and for the year then ended, have been incorporated by reference herein and in the Registration Statement in reliance upon the report of Cacciamatta Accountancy Corporation, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

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$32,500,000
HALOZYME THERAPEUTICS, INC.
Common Stock
Preferred Stock
Debt Securities
Warrants
 
PROSPECTUS
SEPTEMBER ___, 2008

 


PART II
INFORMATION NOT REQUIRED IN PROSPECTUS
ITEM 14. OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION.
     Our expenses in connection with the distribution of the securities being registered hereunder will be substantially as follows (all expenses other than the SEC Registration Fee are estimates):
         
    Company  
Item   Expense  
 
       
SEC Registration Fee
  $ 5,885  
Blue Sky fees and expenses
  $ 5,000  
Printing and engraving expenses
  $ 15,000  
Legal fees and expenses
  $ 50,000  
Accounting fees and expenses
  $ 25,000  
Miscellaneous
  $ 49,115  
 
     
 
       
Total
  $ 150,000  
 
     
ITEM 15. INDEMNIFICATION OF DIRECTORS AND OFFICERS.
     Our bylaws provide for the indemnification of our directors, officers, employees and agents to the fullest extent permitted by the Delaware General Corporation Law (“DGCL”).
     Section 145 of the DGCL provides that a corporation may indemnify any person made a party to an action (other than an action by or in the right of the corporation) by reason of the fact that he or she was a director, officer, employee or agent of the corporation or was serving at the request of the corporation against expenses (including attorneys’ fees), judgments, fines, and amounts paid in settlement actually and reasonably incurred by him or her in connection with such action if he or she acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, the best interests of the corporation and, with respect to any criminal action (other than an action by or in the right of the corporation), has no reasonable cause to believe his or her conduct was unlawful. We have entered into indemnification agreements with our officers and directors.
     Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, we have been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable.

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ITEM 16. EXHIBITS.
     
EXHIBIT    
NUMBER   DESCRIPTION OF DOCUMENT
 
   
1.1
  *Form of Underwriting Agreement
4.1
  **Form of Senior Indenture to be entered into with a trustee to be named
4.2
  **Form of Subordinated Indenture to be entered into with a trustee to be named
4.3
  *Certificate of Designation of Preferred Stock
4.4
  *Form of Warrant Agreement
5.1
  Consent and Opinion of DLA Piper LLP (US)
23.1
  Consent of Independent Registered Public Accounting Firm — Ernst & Young LLP
23.2
  Consent of Independent Registered Public Accounting Firm — Cacciamatta Accountancy Corporation on
23.3
  Consent of DLA Piper LLP (US) (contained in Exhibit 5.1)
24.1
  Power of Attorney (contained on page II-4)
 
*   To be filed by amendment or incorporated by reference from a Current Report on Form 8-K.
 
**   Previously filed.
ITEM 17. UNDERTAKINGS.
(a) The undersigned Registrant hereby undertakes:
  (1)   To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:
(i) To include any prospectus required by section 10(a)(3) of the Securities Act of 1933 (the “Securities Act”);
(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and
(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;
provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

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  (2)   That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
 
  (3)   To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.
(b) The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the Registrant’s annual report pursuant to section 13(a) or section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
(c) The undersigned Registrant hereby undertakes to deliver or cause to be delivered with the prospectus, to each person to whom the prospectus is sent or given, the latest annual report to security holders that is incorporated by reference in the prospectus and furnished pursuant to and meeting the requirements of Rule 14a-3 or Rule 14c-3 under the Securities Exchange Act of 1934; and, where interim financial information required to be presented by Article 3 of Regulation S-X are not set forth in the prospectus, to deliver, or cause to be delivered to each person to whom the prospectus is sent or given, the latest quarterly report that is specifically incorporated by reference in the prospectus to provide such interim financial information.
(d) Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers, and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer, or controlling person of the Registrant in the successful defense of any action, suit, or proceeding) is asserted by such director, officer, or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.
(e) The undersigned Registrant hereby undertakes that:
(1) For the purposes of determining any liability under the Securities Act, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the Registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of the registration statement as of the time it was declared effective.
(2) For the purposes of determining any liability under the Securities Act, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

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SIGNATURES
     Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Post-Effective Amendment No. 1 to the registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of San Diego, State of California, on September 18, 2008.
         
  HALOZYME THERAPEUTICS, INC.
 
 
  By:   /s/ Jonathan E. Lim, M.D.    
    Jonathan E. Lim, M.D.   
    President and Chief Executive Officer
(Principal Executive Officer)
 
 
POWER OF ATTORNEY
     KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Jonathan E. Lim and David A. Ramsay, and each of them, his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities including his or her capacity as a director and/or officer of Halozyme Therapeutics, Inc., to sign any and all amendments (including post-effective amendments) to this registration statement, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes, may lawfully do or cause to be done by virtue thereof.
     Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.
         
Signature   Title   Date
 
       
/s/ Jonathan E. Lim, M.D.
 
Jonathan E. Lim, M.D.
  President and Chief Executive Officer
(Principal Executive Officer),
Director
  September 18, 2008
 
       
/s/ David A. Ramsay
 
David A. Ramsay
  Secretary and Chief Financial Officer
(Principal Financial and Accounting Officer)
  September 18, 2008
 
       
/s/ Gregory I. Frost, Ph.D.
 
Gregory I. Frost, Ph.D.
  Vice President and Chief Scientific Officer,
Director
  September 18, 2008
 
       
/s/ Kenneth J. Kelley
 
Kenneth J. Kelley
  Chairman of the Board of Directors    September 18, 2008
 
       
/s/ Robert L. Engler, M.D.
 
Robert L. Engler, M.D.
  Director    September 18, 2008
 
       
/s/ Kathryn E. Falberg
 
Kathryn E. Falberg
  Director    September 18, 2008
 
       
/s/ Randal J. Kirk
 
Randal J. Kirk
  Director    September 18, 2008

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Signature   Title   Date
 
       
/s/ Connie Matsui
 
Connie Matsui
  Director    September 18, 2008
 
       
/s/ John S. Patton, Ph.D.
 
John S. Patton, Ph.D.
  Director    September 18, 2008
 
       
/s/ Steven T. Thornton
 
Steven T. Thornton
  Director    September 18, 2008

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INDEX TO EXHIBITS
     
EXHIBIT    
NUMBER   DESCRIPTION OF DOCUMENT
 
   
1.1
  *Form of Underwriting Agreement
4.1
  **Form of Senior Indenture to be entered into with a trustee to be named
4.2
  **Form of Subordinated Indenture to be entered into with a trustee to be named
4.3
  *Certificate of Designation of Preferred Stock
4.4
  *Form of Warrant Agreement
5.1
  Consent and Opinion of DLA Piper LLP (US)
23.1
  Consent of Independent Registered Public Accounting Firm — Ernst & Young LLP
23.2
  Consent of Independent Registered Public Accounting Firm — Cacciamatta Accountancy Corporation
23.3
  Consent of DLA Piper LLP (US) (included in Exhibit 5.1)
24.1
  Power of Attorney (contained on page II-4)
 
*   To be filed by amendment or incorporated by reference from a Current Report on Form 8-K
 
**   Previously filed.