Pfizer’s Biosimilar to Epogen Nears Final FDA Approval

The US Food and Drug Administration’s (FDA) Oncologic Drugs Advisory Committee in a 14–1 vote recommended approval of a Pfizer drug that is a biosimilar compound to epoetin alfa (Amgen’s brand name anemia drug Epogen). The committee voted to support the biosimilar drug for approval of all four of Epogen’s clinical indications, making it the first biosimilar of an erythropoiesis-stimulating agent in the US recommended for approval by an FDA advisory committee.

Analytical similarity data between the biosimilar and the FDA-licensed reference product is the basis for biosimilar development. The new biosimilar product must be demonstrated to be “highly similar” to an FDA-licensed biological product under FDA rules. The licensure pathway of a biosimilar means it can be licensed based on “less than a full complement of product-specific preclinical and clinical data,” known as an abbreviated licensure pathway, the FDA states.

In this case, the biosimilar drug, developed by Pfizer’s subsidiary Hospira, was designed to be similar to the reference drug for all of its clinical indications. Epogen is a manmade protein that stimulates red-blood cell production for anemia owing to chronic kidney disease (CKD) and other conditions.

One member of the FDA committee voted against approving the biosimilar for two of four indications, reported Regulatory Focus website. “I have residual concerns about lack of immunogenicity and basic safety data in patients with HIV and cancer, and for that reason I voted ‘no’ for the broader indication,” said Thomas Uldrick, MD, clinical director for the HIV & AIDS Malignancy Branch at the National Cancer Institute. Uldrick did vote to approve the biosimilar drug to treat anemia due to CKD and to reduce allogeneic red blood cell transfusions in patients undergoing elective, noncardiac, nonvascular surgery.

Other panelists agreed with Uldrick regarding the uncertainty due to immunogenicity, but at least one stated that clarity was likely to emerge during postmarket surveillance.

According to the Pink Sheet, a publication that follows biopharma regulations, laws, and business news, only four biosimilar products had been approved by January 2016, although five are slated for review in 2017 to date in first-cycle review. The new epoetin alfa biosimilar drug returned for FDA review after an earlier application failed to pass at the committee approval phase.