The biotech says the SEC’s Atlanta office is conducting an informal inquiry into the Aranesp anemia drug by Danish researchers. The disclosure was contained in the Amgen’s annual report, which you can see here.

The study conducted found that some patients had worse outcomes than those not given the treatment. The researchers ended the trial in October, but Amgen didn’t disclose the results about its best-selling drug until earlier this month after The Cancer Letter asked questions. As Wall Street reacted, Amgen quickly called a teleconference, but the episode sapped investor confidence.

Meanwhile, Amgen says the FDA has “invited” the company to participate in an oncologic drugs advisory committee meeting on May 10 to review its progress in “delineating” the effects of Aranesp and similar meds on survival and tumor progression in cancer patients. The FDA is also looking into a boxed warning for nephrology and oncology indications for the class of erythropoiesis-stimulating agents, or ESAs, a group that includes Aranesp, as well as its own Epogen and Johnson & Johnson’s Procrit.

[tags]Amgen, Aransep[/tags]