Dyax Corp. 300 Technology Square Cambridge, MA 02139 617 225-2500 www.dyax.com Other Offices Dyax SA, Liege, Belgium ADVANCING NOVEL THERAPEUTIC PRODUCTS Dyax Corp. Annual Report 2003 Corporate Information Dyax Achievements 2003 Dyax Goals 2004 Directors Executive Officers and Stock Listing Henry E. Blair Key Employees Common stock has been traded on the Nasdaq Stock Market Advances in Clinical Development Clinical Development Chairman, President and Henry E. Blair* under the symbol DYAX since our initial public offering in Milestones Chief Executive Officer, Chairman, President and August 14, 2000. DX-88/Hereditary Angioedema Dyax Corp. Chief Executive Officer DX-88/Hereditary Constantine E. Stephen S. Galliker, CPA* The following table gives the quarterly high and low sales G Completed 9-patient Phase II trial, met primary endpoints Angioedema Anagnostopoulos, Ph.D. EVP Finance and prices of our common stock for the last three years. G Genzyme Corporation joined Dyax as joint venture partner Managing General Partner, Administration and G Complete Phase II 2001 2002 2003 G Gateway Associates, LP Chief Financial Officer Completed 3 of 4 dose cohorts in 48-patient Phase II EDEMA1 trial EDEMA1 study High Low High Low High Low G Susan B. Bayh, J.D. Lynn G. Baird, Ph.D.* Initiated Phase II EDEMA2 trial G Periodically observe James W. Fordyce SVP Development First Quarter $20.94 $6.56 $11.38 $3.10 $2.25 $1.52 G Orphan Drug designation granted in U.S. and Europe effects of repeat dosing in Phase II EDEMA2 Managing Partner, Robert C. Ladner, Ph.D. Second Quarter $19.99 $6.81 $ 4.68 $3.20 $4.90 $1.67 Fordyce & Gabrielson, LLC SVP and Chief DX-88/On-Pump Open Heart Surgery (CABG) study Third Quarter $21.24 $6.05 $ 4.20 $1.65 $7.50 $2.58 Mary Ann Gray, Ph.D. Technology Officer G G Meet with FDA and Fourth Quarter $11.99 $6.59 $ 2.68 $1.05 $9.05 $4.45 Exercised option to purchase 100% of rights to DX-88 in on-pump open heart surgery President, Ivana Magovc˘evic´, EMEA to determine next and other surgical indications from Genzyme Corporation Gray Strategic Advisors, LLC Ph.D., J.D.* steps toward registration Form 10-K G Completed 42-patient Phase I/II trial, met primary endpoints Thomas L. Kempner SVP Legal Affairs and Additional copies of Dyax’s Annual Report on Form 10-K for Chairman and Chief Chief Patent Counsel DX-88/On-Pump Open the Fiscal Year 2003, as filed with the Securities and Exchange DX-890/Cystic Fibrosis Executive Officer, Clive R. Wood, Ph.D.* Heart Surgery (CABG) Commission, are available without charge upon request from: G Loeb Partners Corporation SVP Discovery Research and Completed second Phase IIa trial (pediatric) Dyax Corp. G Commence Phase II Chief Scientific Officer G Henry R. Lewis, Ph.D. 300 Technology Square Orphan Drug designation granted in U.S. and Europe study in Italy Former Director, Anthony H. Williams, M.D.* Cambridge, MA 02139 Genzyme Corporation SVP Medical Affairs and ATTN: Investor Relations Research Collaboration Highlights: Superior Antibody Phage Display Libraries DX-890/Cystic Fibrosis John W. Littlechild Clinical Operations G Commence next New Funded Research Collaborations General Partner, Fayelle Whelihan, Ph.D. Safe Harbor CF study HealthCare Ventures SVP Discovery Research and This annual report contains forward-looking statements regarding G Alnis BioSciences – Therapeutic peptides (cancer) General Manager, Dyax SA Dyax Corp., including statements regarding its revenues, results of David J. McLachlan operations, financial position, research and development expenditures G Expand Research Baxter Healthcare Corporation – Antibodies to MIF Senior Advisor and Collaborations Transfer Agent and programs, clinical trials and collaborations. Statements that are Former EVP and Chief not historical facts are based on Dyax’s current expectations, beliefs, Positive Results from Existing Research Collaborations Financial Officer, American Stock Transfer assumptions, estimates, forecasts and zprojections for Dyax and Leverage Antibody G Imclone Systems – Antibodies to VEGF-R2 plus 2 undisclosed targets (cancer) Genzyme Corporation & Trust Company the industry and markets in which Dyax competes. Such statements Phage Display Libraries Gregory D. Phelps 59 Maiden Lane are not guarantees of future performance and involve certain risks, G Dendreon Corporation – Antibodies against endothelial serine proteases (cancer) and Automation Former Vice Chairman and New York, NY 10038 uncertainties and assumptions, which are difficult to predict. Capabilities Executive Officer, Therefore, actual outcomes and results may differ materially from New Library and Patent Licensing Agreements what is expressed in such forward-looking statements. Important G New Funded Research Dyax Corp. Legal Counsel factors which may affect future revenues, operating results, financial G Library License Agreements Collaborations Palmer & Dodge LLP position, research and development programs, clinical trials and 111 Huntington Avenue G ImClone Systems (antibodies) G New Library and Patent collaborations include Dyax’s dependence on the expertise, effort, Boston, MA 02199 priorities and contractual obligations of its collaborators in the devel- G MedImmune Inc.(antibodies) Licensing Agreements opment, clinical trials, manufacture, marketing, sales and distribution G G Results from Existing Cross-licensed antibody phage display technology Independent Accountants of biopharmaceuticals developed by Dyax or its collaborators; the risk Research Collaborations that biopharmaceuticals developed by Dyax or its collaborators may G Cambridge Antibody Technologies PricewaterhouseCoopers LLP One Post Office Square not show therapeutic effect or an acceptable safety profile in clinical G Affimed AG Increase Revenues Boston, MA 02109 trials or could take a significantly longer time to gain regulatory from Product approval than Dyax expects or may never gain approval; Dyax’s ability Financing our Future Development and Annual Meeting of to obtain and maintain intellectual property protection for its products Licensing Agreements and technologies; the development of technologies or products superior G Raised over $50 million through common stock offerings Shareholders to Dyax’s technologies or products; and other risk factors described G Sold Biotage subsidiary for $35 million Dyax’s 2004 Annual Meet- or referred to in Dyax’s most recent Form 10-K and other periodic Advance Research ing of Shareholders will Pipeline to Produce reports filed with the Securities and Exchange Commission. Dyax be held at 2:00 p.m. EST cautions investors not to place undue reliance on the forward-looking Focus on Biotherapeutics Next Dyax Clinical on Thursday, May 20th at statements contained in this annual report. These statements speak G All efforts and resources now focused on biotherapeutic product development Candidate Dyax Corp., 300 Technology only as of the date of this annual report, and Dyax undertakes no Square, 8th Floor, obligation to update or revise these statements, except as may be Cambridge, MA. You are required by law. cordially invited to attend. Dyax and the Dyax logo are the registered trademarks of Dyax Corp. Trasylol® is a registered trademark of Bayer Corporation. *Executive Officer Letter to Shareholders I AM PLEASED AND PROUD TO REPORT TO YOU ON DYAX’S PROGRESS DURING 2003. IT HAS BEEN A TREMENDOUS YEAR ON MANY FRONTS. WE MADE SUBSTANTIAL ADVANCES IN THE CLINICAL DEVELOPMENT OF OUR NOVEL SMALL PROTEINS, DX-88 AND DX-890. WE ENTERED INTO NEW REVENUE-GENERATING LICENSING AGREEMENTS AND DRUG DEVELOPMENT COLLABORATIONS THAT HIGHLIGHT OUR SUPERIOR ANTIBODY DISCOVERY CAPABILITIES. WE STREAMLINED OPERATIONS AND RAISED CAPITAL, ALLOWING US TO COMMIT FULL ATTENTION AND RESOURCES TO THERAPEUTIC PRODUCT DEVELOPMENT. POSITIVE CLINICAL TRIAL RESULTS, AS WELL AS INTERNAL AND COLLABORATIVE PRECLINICAL RESULTS, VALIDATED DYAX’S THERAPEUTIC APPROACH AND PROPRIETARY DISCOVERY TECHNOLOGY. Clinical Advances Driving our progress during the year, we announced positive clinical trial results for both of our recombinant compounds in the clinic, DX-88 and DX-890, in all three inflammatory indications being studied – hereditary angioedema (HAE), cystic fibrosis (CF) and coronary artery bypass grafting (CABG) surgery. More details regarding these results are contained herein. Both compounds were also granted orphan drug designation by regulatory authorities in the United States (U.S.) and the European Union (EU); DX-88 for the treatment of angioedema and DX-890 for the treatment of CF.These designations recognize the importance placed on bringing therapeutic alternatives to market for patients living with conditions that have unmet medical needs. Collaborations and Discovery Research Advantages Throughout the year, we established new antibody discovery collaborations and produced positive results for existing collaborators. Today, 80% of the discovery work being done at Dyax is antibody related. We are taking advantage of the market demand for antibodies to generate revenues, and we are producing results that set Dyax apart from other antibody discovery and development companies. Utilizing our state-of-the art discovery capabilities and automation to rapidly identify fully human antibodies, Dyax Corp. Annual Report 2003 we are achieving picomolar to nanomolar affinities, prior to affinity maturation. Some of these antibodies will enter into preclinical studies during 2004. In addition to antibodies, Dyax has made a head start into the future of drug development, where