A Happy Surprise from Amgen
A more potent version of Amgen Inc.'s (AMGN ) Epogen anemia drug can reduce the need for red blood-cell transfusions by more than 50%, cutting hospital stays for cancer patients, according to new studies. Surprisingly, the longer-lasting drug, Aranesp, though designed to treat anemia, may also slow the progression of cancer, according to one study.
The findings, from several large clinical trials designed to show Aranesp's efficacy in treating a common side effect of cancer, were presented at the American Society of Clinical Oncology meeting in San Francisco.
Amgen, based in Thousand Oaks, Calif., is already awaiting approval of Aranesp as an anemia treatment for patients on kidney dialysis in the U.S. and Europe. It now plans to file for approval of the drug as a treatment for cancer patients. Like Epogen, it's a bioengineered protein designed to raise the level of red blood cells, but it lasts about three times longer.
Epogen has been a huge drug for Amgen in the U.S., but Johnson & Johnson holds the rights in Europe, where it's marketed as Procrit. Amgen holds worldwide rights to Aranesp, which some analysts have forecast could eventually bring in sales of $2 billion a year, with half of that amount involving cancer patients.
Anemia -- a drop in the number of red blood cells -- is found in more than 50% of cancer patients and is caused both by the disease and the toxic chemotherapy and radiation treatments. In a Phase 3 trial involving 314 lung-cancer patients, 21% of patients receiving once-weekly doses of Aranesp for 12 weeks needed blood transfusions, compared with 51% of the group on placebo.
Lead investigator Dr. Robert Pirker of the University of Vienna Medical School in Austria said the patients receiving Aranesp were hospitalized for a mean of 10.3 days, compared with 13 days for those on the placebo -- a result the company hadn't been expecting.
Pirker said he also was surprised to discover the median time for progression of the cancer for those on Aranesp was 27 weeks, vs. 19 weeks for the placebo group. Pirker said he could only hypothesize why the disease was slowed: "It could be they had a better response to the chemotherapy, because of oxygenation of the tumors by the increased red blood cells." About 89% of the lung-cancer patients were smokers, he noted, which reduces oxygenation of the blood.
By Catherine Arnst in San Francisco
Edited by Douglas Harbrecht