Affymax and Takeda Announce Preliminary Phase 2 Data Demonstrated That Hematide Increased Hemoglobin in Dialysis Patients

Presentations at American Society of Nephrology Renal Week 2009 Characterize
Binding, Immunogenicity Profile for Hematide
PALO ALTO, Calif. & DEERFIELD, Ill.--(Business Wire)--
Affymax, Inc. (Nasdaq:AFFY) and Takeda Pharmaceutical Global Research &
Development Center, Inc., today announced data from multiple clinical and
preclinical studies evaluating Hematide, including preliminary results of a
Phase 2 trial which demonstrated that Hematide increased hemoglobin levels in a
group of anemic hemodialysis (HD) patients. This is the first reported data from
an open-label, controlled comparative study of once-monthly Hematide compared to
three times per week epoetin alfa (EPO). These results were presented at the
American Society of Nephrology (ASN) Renal Week 2009 in San Diego, CA.
Separately, Hematide is currently being evaluated in four Phase 3 trials for the
treatment of anemia associated with chronic renal failure.

Preliminary data from the Phase 2 randomized, active-controlled, open-label
trial were presented in a poster entitled "Preliminary Analysis of Once-Monthly
Hematide Efficacy and Safety in Hemodialysis Patients not on erythropoiesis
stimulating agent (ESA) Treatment." The trial enrolled 114 hemodialysis patients
who were not actively undergoing ESA treatment. In these patients, hemoglobin
levels were between 8.0 g/dL and 11.0 g/dL at baseline. According to the
National Kidney Foundation, hemoglobin levels should generally be maintained in
the range 11.0 g/dL to 12.0 g/dL. Patients were randomized to receive one of
three starting doses: intravenous Hematide once every four weeks (0.04 mg/kg or
0.08 mg/kg) or intravenous EPO three times per week (50 U/kg). Preliminary
results showed Hematide treated anemia as measured by increasing hemoglobin
levels and maintaining them at the target range in this patient population.
Moreover, patients in the Hematide group appeared to show treatment results
comparable to patients in the EPO group.

Further, after 12 weeks of treatment, the mean hemoglobin levels for all three
patient groups increased from a mean overall baseline of 9.2 g/dL to the target
range of 11-12 g/dL where it was maintained through the rest of the study. At
the time of the preliminary analysis, 11% of patients had experienced a serious
adverse event. These events included arteriovenous (AV) thrombosis and vitreous
hemorrhage. A single serious adverse event considered treatment-related was a
case of arteriovenous fistula thrombosis that occurred in the lowest dose of
Hematide (0.04 mg/kg). Adverse events considered possibly treatment-related
occurred in approximately 9% of the patients. Hypertension was the only
treatment related adverse event that occurred in more than one patient (8% in
the Hematide 0.04 mg/kg group, 3% in the Hematide 0.08 mg/kg group and 8% in the
EPO 50 U/kg group).

"Anemia remains a significant co-morbidity of chronic kidney disease and is
associated with increased rates of hospitalization and mortality," said
Anne-Marie Duliege, M.D., chief medical officer of Affymax, Inc. "In the
preliminary analysis of this study to increase hemoglobin levels of anemic
dialysis patients not on ESAs, Hematide, used once a month, appeared to have
treatment effects comparable to epoetin alfa used three times per week."

Additional clinical and preclinical studies with Hematide are being presented at
the meeting. They include data from a Phase 2 clinical trial evaluating
Hematide`s ability to raise hemoglobin levels in patients with pure red cell
aplasia (PRCA), as well as preclinical studies evaluating the immunogenicity,
binding characteristics and mechanism of action of Hematide.

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 once approved in the United States. The product,
upon approval, will be commercialized in the European Union by Takeda. Phase 3
clinical trials are being conduced to investigate the potential for Hematide to
treat anemia associated with chronic renal failure.

About Anemia in Chronic Renal Failure (CRF)

Anemia in CRF affects many individuals with Chronic Kidney Disease (CKD).
According to the National Kidney Foundation, 26 million Americans - 1 in 9 U.S.
adults - have CKD. Anemia develops in the early stages of CKD and worsens as
patients progress towards total kidney failure and need a dialysis machine to
eliminate waste and water from their blood. In severe or prolonged cases of
anemia, the lack of oxygen in the blood can cause serious and sometimes fatal
damage to the heart and other organs. Benefits of anemia correction in patients
with CKD include decreased morbidity, hospitalization, and mortality.1

About Takeda Pharmaceuticals North America, Inc.and Takeda Global Research &
Development Center, Inc.

Based in Deerfield, Ill., Takeda Pharmaceuticals North America, Inc. and Takeda
Global Research & Development Center, Inc. are subsidiaries of Takeda
Pharmaceutical Company Limited, the largest pharmaceutical company in Japan. The
respective companies currently market oral diabetes, insomnia, rheumatology and
gastroenterology treatments and seek to bring innovative products to patients
through a pipeline that includes compounds in development for diabetes,
cardiovascular disease, gastroenterology, neurology and other conditions. To
learn more about these Takeda companies, visit www.tpna.com.

About Affymax, Inc.

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

This release contains forward-looking statements, including statements regarding
the success of the collaboration, timing, design and results of the Company's
clinical trials and drug development program and the timing and likelihood of
the commercialization of Hematide. The Company's 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 and
room temperature stability, the cardiovascular event rate in our Phase 3
program, 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 quarterly report on Form 10-Q
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 Company undertakes no obligation to update any
forward-looking statement in this press release.

1. http://www.anemia.org/pdf/mon_Anemia_and_CKD.pdf

Affymax, Inc.
Sylvia Wheeler, 650-812-8861
Executive Director, Corporate Communications
or
Takeda Global Research & Development Center, Inc.
Julia Ellwanger, 224-554-7681
Corporate Communications

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