Dyax Corp. Announces Expansion of Phase 1b Clinical Trial for DX-2930

Dyax Corp. (NASDAQ: DYAX) today announced the expansion of its ongoing Phase 1b clinical trial evaluating DX-2930 to include additional patients and dosing cohorts. Dyax is developing DX-2930, an investigational fully human monoclonal antibody inhibitor of plasma kallikrein, as a subcutaneous injection for prevention of hereditary angioedema (HAE) attacks.

The ongoing Phase 1b clinical trial is a multi-center, randomized, double-blind, placebo-controlled, multiple ascending dose study designed to assess the safety, tolerability and pharmacokinetics of DX-2930 in HAE patients. As of October 31, 2014, 21 subjects were enrolled and completed dosing in three ascending dose cohorts (30 mg, 100 mg and 300 mg) of DX-2930 or placebo. Subjects in each cohort were randomized to active drug or placebo in a 2:1 ratio. Each study subject received two doses of study drug or placebo separated by 14 days and will undergo 15 weeks of follow-up after the second dose.

In light of faster than anticipated enrollment rates, Dyax has decided to take the opportunity to further characterize DX-2930 by adding two additional cohorts. Subjects will continue to be randomized to active drug or placebo in a 2:1 ratio and the dosing regimen will remain unchanged. Active drug-treated subjects in the fourth cohort will receive 400 mg of DX-2930. The dose level of the fifth cohort will be decided based upon a review of interim data.

Addition of the new dosing cohorts is in accordance with the provisions included in the original protocol which allows enrollment into additional dose groups and/or additional patients at any dose group. Total enrollment can be increased to as many as 36 patients and data from additional patients will be used to expand the DX-2930 safety database and provide potentially informative pharmacodynamic data.

“Strong investigator support for the Phase 1b trial has allowed the study to progress rapidly and, at this time, the first three dosing cohorts are fully enrolled,” said Burt Adelman M.D., Executive Vice President of Research and Development and Chief Medical Officer at Dyax. “These additional cohorts will provide safety, pharmacokinetic and pharmacodynamic data which will further guide future clinical development of DX-2930. Importantly, we remain on track to report data from this study in early 2015, followed by a Phase 2 study which is also currently planned to begin in 2015.”

"Developing a prophylactic treatment for HAE patients is a key value driver for Dyax and we are encouraged by the rapid progress we are seeing with this trial," said Gustav Christensen, President and Chief Executive Officer of Dyax. "We believe DX-2930’s unique product profile positions it well as a potential preventative treatment for HAE attacks.”

About DX-2930
DX-2930 is a novel, fully human monoclonal antibody inhibitor of plasma kallikrein (pKal) and is being developed by Dyax as a subcutaneous injection for the prevention of HAE attacks. Uncontrolled pKal activity leads to excessive generation of bradykinin, a vasodilator thought to be responsible for the localized swelling, inflammation and pain characteristically associated with HAE.

About HAE
HAE is a rare acute inflammatory condition characterized by episodes of severe, often painful swelling affecting the extremities, gastrointestinal tract, genitalia, and larynx. HAE is caused by low or dysfunctional levels of C1 esterase inhibitor (C1-INH), a naturally occurring molecule that inhibits plasma kallikrein, a key mediator of inflammation, and other serine proteases in the blood. HAE is estimated to affect up to 1 in 50,000 individuals. Learn more at www.HAEHope.com.

About Dyax
Dyax is a fully integrated biopharmaceutical company focused on the discovery, development and commercialization of novel biotherapeutics for unmet medical needs. The Company currently markets KALBITOR® (ecallantide) for the treatment of acute attacks of hereditary angioedema (HAE) in patients 12 years of age and older. Dyax is also developing DX-2930, a fully human monoclonal antibody, for the potential prophylactic treatment of HAE.

Both KALBITOR and DX-2930 were identified using Dyax's proprietary phage display technology. Dyax has broadly licensed this technology and has a portfolio of product candidates being developed by its licensees, which it refers to as the LFRP. The Company is eligible to receive future milestones and/or royalties dependent upon the development and commercialization of these candidates. In 2014, Dyax’s licensee Eli Lilly and Company began marketing their FDA approved product, CYRAMZA® (ramucirumab), as a single-agent treatment for patients with advanced gastric cancer after prior chemotherapy, making this the first royalty-bearing therapeutic product from Dyax’s LFRP.

For additional information about Dyax, please visit www.dyax.com.

For additional information about KALBITOR, including full prescribing information, please visit www.KALBITOR.com.

Disclaimer
This press release contains forward-looking statements, including statements regarding the prospects for the clinical development of DX-2930. Statements that are not historical facts are based on Dyax’s current expectations, beliefs, assumptions, estimates, forecasts and projections about the industry and markets in which Dyax and its licensees compete. The statements contained in this release are not guarantees of future performance and involve certain risks, uncertainties and assumptions, which are difficult to predict. Therefore, actual outcomes and results may differ materially from what is expressed in such forward-looking statements because of risks, uncertainties and assumptions involved in any future projections. There are many factors that could cause actual results to differ from these forward-looking statements, including: risks and uncertainties relating to the clinical development of DX-2930; Dyax's dependence on the expertise, effort, priorities and contractual obligations of third parties in the manufacture, quality control, storage and clinical development of DX-2930; changing requirements and costs associated with Dyax's planned research and development activities; competition from new and existing treatments for HAE; the uncertainty of patent and intellectual property protection; and other risk factors described or referred to in Item 1A, “Risk Factors” in Dyax’s most recent Annual Report on Form 10-K and other periodic reports filed with the Securities and Exchange Commission. Dyax cautions investors not to place undue reliance on the forward-looking statements contained in this release. These statements speak only as of the date of this release, and Dyax undertakes no obligations to update or revise these statements, except as may be required by law.

Dyax, the Dyax logo and KALBITOR are registered trademarks of Dyax Corp.
CYRAMZA® is a registered trademark of Eli Lilly and Company.