Dyax Corp. (NASDAQ: DYAX) today announced that the U.S. Patent and Trademark Office (USPTO) has issued two new patents related to DX-2930, an investigational fully human monoclonal antibody inhibitor of active plasma kallikrein. One patent, assigned U.S. Patent No. 8,816,055, contains claims covering the specific sequence of DX-2930, and the other, assigned U.S. Patent No. 8,822,653, contains claims covering monoclonal antibodies that bind to the active form of human plasma kallikrein and do not bind human pre-kallikrein. Both patents are expected to provide coverage for DX-2930 until at least 2032.

“These newly issued patents contain broad composition of matter claims which provide important long-term exclusivity for DX-2930, especially its binding properties to human plasma kallikrein, which we believe is a critical target in the treatment for hereditary angioedema (HAE),” said Gustav Christensen, President and Chief Executive Officer of Dyax. “Collectively, they further validate Dyax’s discovery capabilities and confer a unique and robust intellectual property estate surrounding DX-2930, enhancing its commercial potential.”

Dyax, a biopharmaceutical company focused on HAE and other plasma-kallikrein-mediated disorders, is developing DX-2930 as a subcutaneous injection for prevention of HAE attacks.

About DX-2930

DX-2930 is a novel, fully human monoclonal antibody inhibitor of active plasma kallikrein (pKal). 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. Dyax is currently developing DX-2930 as a subcutaneous injection for the prevention of HAE attacks and expects to report data from a Phase 1b trial early in 2015.

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 HAE in patients 12 years of age and older. Dyax is also developing DX-2930 for the prophylactic treatment of HAE.

Both KALBITOR and DX-2930 were identified using Dyax's patented 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 Licensing and Funded Research Portfolio (LFRP). The Company is eligible to receive future milestones and/or royalties dependent upon the development and commercialization of these candidates. In April 2014, Dyax’s licensee Lilly received FDA approval for CYRAMZA™ (ramucirumab) as a single-agent treatment for patients with advanced gastric cancer after prior chemotherapy, making this the first approved 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 and strength of intellectual property and commercial prospects for 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 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.