The biotech made several changes to the warning labels on its EPO drugs, Aranesp and Epogen, and six new clinical trials are being proposed to assess their safety in treating chemotherapy-induced anemia in specific types of tumors. The revised labels say therapy should end following the completion of chemotherapy, and patient dosing should be adjusted to achieve and maintain the lowest hemoglobin level possible to avoid a blood transfusion. The warnings also state that the hemoglobin level should not exceed the upper safety limit of 12 grams per deciliter of blood.

The changes to the boxed warnings include additional language in the indications and usage section, addition of an oncology study to the warnings section, and clarification of the hemoglobin range for chronic renal failure patients in the dosage and administration section. For more details, you can read the Amgen statement. UPDATE: And this is the FDA warning, which also applies to Johnson & Johnson’s Procrit.

But Amgen continues to differ with the Centers for Medicare and Medicaid, which this summer set a ceiling of 10 grams per deciliter for reimbursement. The decision infuriated the biotech, which began lobbying Congress with the help of the American Society of Hematology and the American Society of Clinical Oncology. Citing a recent decision by the European Medicines Agency, EMEA, that a range of 10 to 12 g/dl is permissable - with a warning not to exceed 12 g/dl - the biotech plans to submit “new evidence” in hopes of convincing CMS to change its New Coverage Decision, or NCD.

“Major US health plans announced that they will continue to base their coverage policies on evidence-based clinical practice guidelines and not adopt the NCD,” Amgen said in the second of two statements issued this morning. “In this regard, the NCD has created an unprecedented two-tiered healthcare system based solely on insurance status: one for patients covered by Medicare and another for those with private healthcare coverage.” Look here for more.

By bundling these announcements, Amgen is trying to convince investors, doctors and regulators that it can be more responsive to safety concerns and, of course, justify its plan to petition Medicare for a reversal. The strengthened warnings, however, were necessary, apart from any CMS decision, given recommendations by an FDA advisory panel. A lot of money is at stake, though, and so the big issue now is whether CMS alters its position. Wall Street analysts have largely indicated this won’t happen. The lobbying will be interesting to watch.

UPDATE: Jim Reddoch, a biotech analyst at Friedman Billings Ramsey, doesn’t think CMS will change its mind. “We think this label gives the CMS some leverage in the ongoing debate about whether or not to overturn the recent NCD and, despite Amgen’s and various medical groups efforts, we think it is highly unlikely it will be overturned, especially since the FDA just sent a letter last month to Pete Stark stating the NCD is consistent with the FDA label and the label has basically remained unchanged since then.”