Amgen had already said there was a higher death rate in preliminary data released in January. The overall number of deaths was greater in the Aranesp group at 48.5% compared to 46% in placebo.
This phase III study was designed to evaluate the efficacy and safety of Aranesp 6.75 mcg/kg administered every four weeks for the treatment of anemia in cancer patients not receiving chemotherapy or radiotherapy. Aranesp is not approved for use by the FDA or EMEA in these patients.
Amgen said it could not explain why there was an increased death rate for those administered Aranesp.
“Since this was not designed as a survival study and statistical significance diminished when the analyses were adjusted for known prognostic factors, there is no clear explanation for the increase of deaths in the Aranesp group.” said John Glaspy, professor, David Geffen School of Medicine, University of California.
The company also commented that Aranesp would not be beneficial for patients with active cancer, not receiving chemotherapy or radiation, who are anemic due to the cancer itself. Amgen is no longer pursuing approval of Aranesp for this indication.
Additionally, the study did not meet its primary endpoint of reducing red blood cell transfusions in the Aranesp treatment group. Transfusion occurrences from weeks 5 to 17 favored Aranesp but were not statistically significant between the groups.