Affymax breaks Amgen's anemia drug monopoly with ESA approval

Amgen has finally lost control of the U.S. market for anemia drugs needed to treat dialysis patients. In the middle of the day the FDA announced that it had handed Affymax ($AFFY) an approval for peginesatide--an ESA therapy that will be sold as Omontys. The approval paves the way to the entry of a rival for Epogen, Amgen's ($AMGN) longtime anemia blockbuster, which will offer patients a much easier dosing schedule.

Peginesatide's biggest advantage is that patients will only need once-monthly injections, compared to up to 12 times a month for Epogen patients. That is likely to open lots of doors in the market of some 400,000 patients. And the FDA was acutely aware of the lack of competition in the market when it announced the news of the approval.

"Omontys represents the first new FDA-approved and marketed ESA for this condition since 2001," said Richard Pazdur, M.D., CDER's director of the Office of Hematology and Oncology Products. "This new drug offers patients and health care providers the convenience of receiving ESA therapy just once per month instead of more frequent injections."

The approval marks a big victory for Affymax, which had to battle back from the cardiovascular risk signals seen in 2010 to win over regulators. Takeda will split the U.S. market with Affymax. The news is also good for Nektar ($NKTR), which helped on the delivery side of the program. Nektar wins a single-digit royalty stream with the approval.

Amgen has been digging a deep defensive position for itself in the anemia market. It has an exclusive supplier relationship with DaVita which covers the bulk of its anemia drug needs for seven years. And Fresenius struck a nonexclusive supply deal. That still leaves a large chunk of the marketplace for small- and medium-sized dialysis centers, which analysts note are particularly price sensitive. Peginesatide is expected to bring in $700 million a year, with much of that money redirected from the Epogen franchise.

- here's the press release
- read the story from Bloomberg
- get the Xconomy story