- Pfizer has hit a surprise roadblock in its bid to win approval of a biosimilar version of epoetin alfa, disclosing Thursday the Food and Drug Administration rejected its proposed copy to the anemia drug.
- In a complete response letter, the regulator cited a previous warning letter sent to the pharma giant about manufacturing violations at its McPherson, Kansas plant. Pfizer had listed the facility as a potential production site for the biosimilar candidate on its Biologics License Application.
- No additional clinical data was requested, nor did any violations flagged in the February warning letter directly relate to production of biosimilar epoetin alfa. Approval of the copycat biologic had been expected after a FDA advisory panel recommended approval in a May meeting.
Issues with legacy Hospira plants continue to hamstring Pfizer. The big pharma inherited a number of manufacturing issues in its 2015 acquisition of Hospira, and the company has been chipping away at bringing the sites into compliance with the FDA.
The February warning issued to the McPherson facility was another headache in that process, although Pfizer CEO Ian Read has noted the inspection which triggered a letter from the FDA came within the first nine months after the Hospira acquisition.
In a statement on the rejection, Pfizer said it submitted a corrective and preventative action plan for bringing the McPherson site up to code back in March, and is "dedicated to addressing all of the FDA's concerns."
Sales of branded epoetin alfa — which is sold as Epogen and Procrit by Amgen and Johnson & Johnson, respectively — totaled nearly $2.4 billion last year.
Amgen, however, recorded a 31% decline in Epogen sales, which fell to $1.28 billion last year. Declines in demand and shifting sales in the dialysis setting to Amgen's other anemia drug Aranesp (darbepoetin alfa) accounted for much of the decline.
J&J sales of Procrit grew by 3.5% in 2016 versus a year prior, although the company saw a roughly 10% sales decline over the first three months of 2017.
Pfizer had already lined up Vifor Pharma as a distributor of its epoetin alfa biosimilar to the dialysis market, which is big business for anemia drugs. Three-quarters of all Epogen sales, for instance, go to free-standing dialysis clinics owned or managed by DaVita and Fresensius Medical Care North America.
The FDA's rejection sets back those plans and gives Amgen and J&J some additional breathing room competitively.