Affymax Lives to Fight Another Day, In Bid to Challenge Amgen’s Monopoly

to last longer in the bloodstream, requiring only one injection a month for anemia. This provides one less thing doctors and patients need to do during the dialysis visits, and makes for simpler insurance reimbursement procedures, Morris says. What’s more important, though, is that Affymax and Takeda are considering whether to offer their drug at a lower price than Amgen’s—which could provide a compelling reason for dialysis clinics to switch in an era of tightening Medicare reimbursement for kidney patients.

Affymax and Takeda are still a long way from setting the price for the anemia drug, but Morris says they could decide to offer a lower price. “People have been looking for 18 years for someone else to come into the market,” Morris says. “Because it’s a monopoly, they can charge whatever they want.”

Before any of that can come to fruition, Affymax and Takeda will have to make a compelling case to the FDA that their drug deserves a spot on the market. The agency has spent a lot of time and energy thinking about the risks and benefits of the drugs made by Amgen, after a series of safety warnings came out in 2007 alerted doctors to higher risk of heart attack, stroke and death when those treatments are used in high doses. That whole debacle chopped $29 billion off of Amgen’s market valuation that year. While Amgen suffered through that period, Affymax was crafting its game plan, beginning its series of four pivotal studies that ended up enrolling 2,609 patients with kidney disease at varying degrees of severity.

The first look at the data, as mentioned above, wasn’t encouraging to investors. Affymax and Takeda looked at a composite safety score on cardiovascular health, which combined death, stroke, heart attack, congestive heart failure, unstable angina, and arrhythmia. On that important measurement, 21.6 percent of non-dialysis patients had an adverse event while on the Affymax/Takeda product. That compared with 17.1 percent of patients on the Amgen drug.

While that made the new drug look like a riskier choice, the situation was reversed when Affymax and Takeda looked at patients in the end stage of kidney disease (dialysis). In those patients, 22.8 percent on the Affymax drug had a cardiovascular adverse event, while 24.4 percent had one while taking the Amgen product.

Affymax was “obviously surprised,” Morris says, to see the higher rate of cardiovascular adverse events in the non-dialysis patients. And after weeks of digging into the data, she said the companies still haven’t determined exactly why that happened. Affymax and Takeda aren’t planning to seek FDA approval for the non-dialysis patient population, although Morris wouldn’t quite go so far as to say the product has no future for those patients.

Researchers have floated at least one hypothesis that Morris shared with me. The idea is that many kidney disease patients also coincidentally have heart trouble, and many of them die from it before they ever progress all the way to end-stage renal disease (dialysis). That means the dialysis patient population is naturally self-selected to be people with hardy cardiovascular health, and less likely to be perturbed by an anemia therapy.

Really, though, it’s just an idea, not iron-clad

Author: Luke Timmerman

Luke is an award-winning journalist specializing in life sciences. He has served as national biotechnology editor for Xconomy and national biotechnology reporter for Bloomberg News. Luke got started covering life sciences at The Seattle Times, where he was the lead reporter on an investigation of doctors who leaked confidential information about clinical trials to investors. The story won the Scripps Howard National Journalism Award and several other national prizes. Luke holds a bachelor’s degree in journalism from the University of Wisconsin-Madison, and during the 2005-2006 academic year, he was a Knight Science Journalism Fellow at MIT.