Affymax and Takeda Report Long-Term Safety and Effectiveness Data of Hematide in Chronic Renal Failure Patients With Anemia.

Phase 2 Findings Presented at the National Kidney Foundation 2008 Spring Meeting

DALLAS -- Affymax, Inc. (Nasdaq:AFFY) and Takeda Global Research & Development today announced data from their ongoing Phase 2 trial to assess the long-term safety and tolerability of Hematide[TM], a potential treatment of anemia. These data showed that Hematide, dosed once every four weeks, successfully maintained mean hemoglobin levels between 11 and 12 g/dL for up to 18 months in hemodialysis patients who previously were treated with epoetin alfa. Hematide appeared generally well-tolerated.

Robert Geronemus, M.D., associate professor, Florida Atlantic University and medical director, South Florida Research Institute, is the lead author of the poster which was presented at the National Kidney Foundation 2008 Spring Clinical Meeting.

"These data are encouraging because they demonstrate the ability of Hematide to maintain mean stable hemoglobin levels in these chronic renal failure study participants, while only dosing once every four weeks," said Dr. Geronemus.

About the Phase 2 Study

81 dialysis patients, originally enrolled in an open-label study to evaluate a switch from epoetin alfa to Hematide, were rolled over to the long-term Phase 2 trial, and then maintained on Hematide for the duration of the follow-up study. The patients received intravenous Hematide once every four weeks for approximately 18 months, totaling 18 doses. Dosing was designed to maintain Hb between 10-12.0 g/dL. In this analysis at 18 months, the mean hemoglobin value was 11.3 g/dL.

Generally, Hematide was well-tolerated in this study. Five patients or 6.2 percent experienced adverse events assessed as possibly related to Hematide, such as diarrhea, feeling hot, insomnia, oedema peripheral, and pain in extremities. Other adverse events were assessed as not related to study drug.

About Hematide

Hematide is a novel synthetic, pegylated peptidic compound that binds to and activates the erythropoietin receptor and thus acts as an erythropoiesis stimulating agent (ESA).

Affymax and Takeda are collaborating on the development of Hematide and plan to co-commercialize the product in the United States. The product, upon approval, will be commercialized in the European Union by Takeda. Affymax is conducting Phase 3 clinical trials for Hematide to treat anemia associated with chronic renal failure and Takeda is focused on the recently initiated Phase 1 clinical trial in the U.S. to evaluate Hematide to treat chemotherapy-induced anemia in prostate, breast and non-small cell lung cancer patients.

About Affymax, Inc.

Affymax, Inc. is a biopharmaceutical company developing novel drugs to improve the treatment of serious and often life-threatening conditions. For additional information, please visit www.affymax.com.

Takeda Global Research & Development Center, Inc.

Based in Deerfield, Ill., and London, U.K., Takeda Global Research & Development Center, Inc. is a wholly owned subsidiary of Takeda Pharmaceutical Company Limited, the largest pharmaceutical company in Japan. Takeda Global Research & Development was established in 2004 and is responsible for Takeda's clinical research and development in the U.S. and Europe, supporting clinical and product development activity for Takeda commercial organizations in the U.S. - Takeda Pharmaceuticals North America, Inc, and in Europe: six sales and marketing companies, respectively. With a robust pipeline of compounds in development for diabetes, cardiovascular disease and other conditions, Takeda rapidly brings innovative products to market to improve patient health and enhance the practice of medicine. To learn more about the company, visit www.tgrd.com.

This release contains forward-looking statements, including statements regarding the success of the collaboration, timing, design and results of the Companies' clinical trials and drug development program and the timing and likelihood of the commercialization of Hematide. The Companies' actual results may differ materially from those indicated in these forward-looking statements due to risks and uncertainties, including risks relating to the continued safety and efficacy of Hematide in clinical development, the potential for once per month dosing, the timing of patient accrual in ongoing and planned clinical studies, regulatory requirements and approvals, research and development efforts, industry and competitive environment, intellectual property rights and disputes and other matters that are described in Affymax's Annual Report on Form 10-K filed with the Securities and Exchange Commission. Investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this release. The Companies undertake no obligation to update any forward-looking statement in this press release.