Affymax and Takeda Announce Permanent J-Code for OMONTYS® (peginesatide) Injection is in Effect

Code J0890 Effective as of January 1, 2013

PALO ALTO, Calif. and DEERFIELD, Ill., January 3, 2013 – Affymax, Inc. (Nasdaq:AFFY) and Takeda Pharmaceuticals U.S.A., Inc. (TPUSA) today announced that the J-code assigned by the Centers for Medicare and Medicaid Services (CMS) for OMONTYS® (peginesatide) Injection is now effective. This permanent OMONTYS-specific billing code, J0890, will continue to provide for streamlined reimbursement for dialysis organizations prescribing OMONTYS. OMONTYS is the only once-monthly erythropoiesis-stimulating agent (ESA) for anemia available to the adult dialysis patient population with chronic kidney disease (CKD) in the United States (U.S.).

“We are excited by the strong level of interest in the dialysis community for OMONTYS,” said John Orwin, chief executive officer, Affymax. “We believe the J-code complements our efforts to make this once-monthly therapy broadly available to the dialysis community, and importantly, to appropriate patients.”

According to Nicole Mowad-Nassar, vice president, marketing at Takeda, “We are pleased to have an effective J-code in place approximately nine months following the approval of OMONTYS.”

OMONTYS was approved by the U.S. Food and Drug Administration (FDA) on March 27, 2012, for the treatment of anemia due to CKD in adult patients on dialysis. OMONTYS is not indicated and is not recommended for use in patients with CKD not on dialysis, in patients receiving treatment for cancer and whose anemia is not due to CKD, or as a substitute for red blood cell (RBC) transfusions in patients who require immediate correction of anemia. OMONTYS has not been shown to improve symptoms, physical functioning, or health-related quality of life. Please see Important Safety Information including Boxed WARNINGS below.

Information on OMONTYS Reimbursement Support
Customers seeking additional information about accessing the product can refer to the OMONTYS Reimbursement Access Support (RAS) program. RAS offers comprehensive reimbursement access, and support services for healthcare providers. For more information please call 1-855-GOMONTYS (1-855-466-6689) for more information.

About OMONTYS® (peginesatide) Injection
OMONTYS is a synthetic, pegylated ESA. It is the only ESA that is peptide-based and its building blocks (amino acids) are arranged in a different order than erythropoietin (i.e., it has no sequence homology to endogenous erythropoietin).

On March 27, 2012, the FDA approved OMONTYS for the treatment of anemia due to CKD in adult patients on dialysis. OMONTYS is the first ESA to be introduced to the U.S. market in over 10 years. It is the only once-monthly ESA for anemia available to this patient population in the United States.

IMPORTANT SAFETY INFORMATION

Contraindications

OMONTYS is contraindicated in patients with uncontrolled hypertension and in patients who have had serious allergic reactions to OMONTYS.

Warnings and Precautions
Increased mortality, myocardial infarction, stroke, and thromboembolism:

• Using ESAs to target a hemoglobin level of greater than 11 g/dL increases the risk of serious adverse cardiovascular reactions and has not been shown to provide additional benefit. Use caution in patients with coexistent cardiovascular disease and stroke. Patients with CKD and an insufficient hemoglobin response to ESA therapy may be at even greater risk for cardiovascular reactions and mortality. A rate of hemoglobin rise of >1 g/dL over 2 weeks may contribute to these risks.
• In controlled clinical trials of ESAs in patients with cancer, increased risk for death and serious adverse cardiovascular reactions including myocardial infarction and stroke was observed.
• There is increased mortality and/or increased risk of tumor progression or recurrence in patients with cancer receiving ESAs.
• In controlled clinical trials of ESAs, ESAs increased the risk of death in patients undergoing coronary artery bypass graft surgery (CABG) and deep venous thrombosis (DVT) in patients undergoing orthopedic procedures.
• In 2 trials of OMONTYS, patients with CKD not on dialysis experienced increased specific cardiovascular events.

Hypertension (see Contraindications): Appropriately control hypertension prior to initiation of and during treatment with OMONTYS. Reduce or withhold OMONTYS if blood pressure becomes difficult to control.

Serious allergic reactions (see Contraindications): Serious allergic reactions have been reported with OMONTYS. Immediately and permanently discontinue OMONTYS and administer appropriate therapy if a serious allergic reaction occurs.

Lack or loss of response to OMONTYS: Initiate a search for causative factors. If typical causes of lack or loss of hemoglobin response are excluded, evaluate for antibodies to peginesatide.

Dialysis management: Patients receiving OMONTYS may require adjustments to dialysis prescriptions and/or increased anticoagulation with heparin to prevent clotting of the extracorporeal circuit during hemodialysis.

Laboratory monitoring: Evaluate transferrin saturation and serum ferritin prior to and during OMONTYS treatment. Administer supplemental iron therapy when serum ferritin is less than 100mcg/L or when serum transferrin saturation is less than 20%. Monitor hemoglobin every 2 weeks until stable and the need for RBC transfusions is minimized. Then, monitor monthly.

Adverse reactions
Most common adverse reactions in clinical studies in patients with CKD on dialysis treated with OMONTYS were dyspnea, diarrhea, nausea, cough, and arteriovenous fistula site complication.

Please click here for Full Prescribing Information, including Boxed WARNINGS, also available at www.omontys.com.

OMONTYS Indication and Limitations of Use
OMONTYS® (peginesatide) Injection is indicated for the treatment of anemia due to chronic kidney disease (CKD) in adult patients on dialysis.

OMONTYS is not indicated and is not recommended for use in patients with CKD not on dialysis, in patients receiving treatment for cancer and whose anemia is not due to CKD, or as a substitute for red blood cell (RBC) transfusions in patients who require immediate correction of anemia. OMONTYS has not been shown to improve symptoms, physical functioning, or health-related quality of life.

About Affymax, Inc.
Affymax, Inc. is a biopharmaceutical company based in Palo Alto, California. Affymax's mission is to discover, develop and deliver innovative therapies that improve the lives of patients with kidney disease and other serious and often life-threatening illnesses.

The company's first marketed product, OMONTYS, was approved by the U.S. Food and Drug Administration (FDA) in March 2012. For additional information on Affymax, please visit www.affymax.com.

Affymax Forward-Looking Statement
This release contains forward-looking statements, including statements regarding the importance of the J-code, the potential advantages of OMONTYS, the continuation and success of Affymax's collaboration with Takeda and the commercialization of OMONTYS. Affymax's actual results may differ materially from those indicated in these forward-looking statements due to risks and uncertainties, including risks relating to the factors affecting the commercial potential of OMONTYS, the continued safety and efficacy of OMONTYS, industry and competitive environment, regulatory requirements by the FDA or other regulatory authorities, including post-marketing studies, trials and Risk Evaluation and Mitigation Strategy, the potential for disruptions to supply, financing requirements and our ability to access capital 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. Affymax undertakes no obligation to update any forward-looking statement in this press release.

About Takeda Pharmaceuticals U.S.A., Inc. and Takeda Global Research & Development Center, Inc.
Based in Deerfield, Ill., Takeda Pharmaceuticals U.S.A., 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, gastroenterology and cardiovascular disease treatments and seek to bring innovative products to patients through a pipeline that includes compounds in development for diabetes, gastroenterology, neurology and other conditions. To learn more about these Takeda companies, visit www.tpna.com.

Takeda Forward-Looking Statement
This press release contains forward-looking statements. Forward-looking statements include statements regarding Takeda's plans, outlook, strategies, results for the future, and other statements that are not descriptions of historical facts. Forward-looking statements may be identified by the use of forward-looking words such as "may," "believe," "will," "expect," "project," "estimate," "should," "anticipate," "plan," "assume," "continue," "seek," "pro forma," "potential," "target," "forecast," "guidance," "outlook" or "intend" or other similar words or expressions of the negative thereof. Forward-looking statements are based on estimates and assumptions made by management that are believed to be reasonable, though they are inherently uncertain and difficult to predict. Investors are cautioned not to unduly rely on such forward-looking statements.

Forward-looking statements involve risks and uncertainties that could cause actual results or experience to differ materially from that expressed or implied by the forward-looking statements. Some of these risks and uncertainties include, but are not limited to, (1) the economic circumstances surrounding Takeda's business, including general economic conditions in Japan, the United States and worldwide; (2) competitive pressures and developments; (3) applicable laws and regulations; (4) the success or failure of product development programs; (5) actions of regulatory authorities and the timing thereof; (6) changes in exchange rates; (7) claims or concerns regarding the safety or efficacy of marketed products or product candidates in development; and (8) integration activities with acquired companies.

The forward-looking statements contained in this press release speak only as of the date of this press release, and Takeda undertakes no obligation to revise or update any forward-looking statements to reflect new information, future events or circumstances after the date of the forward-looking statement. If Takeda does update or correct one or more of these statements, investors and others should not conclude that Takeda will make additional updates or corrections.

SOURCE: Affymax, Inc. and Takeda Pharmaceuticals U.S.A., Inc.

Contacts:

Jessica Tuquero
Corporate Communications
Takeda Pharmaceuticals U.S.A., Inc.
224-554-2021