FDA to Require Additional Study for Eagle’s Generic Vasopressin
Eagle Pharmaceuticals is still struggling to get its generic vasopressin to market, announcing both a regulatory stall and an additional trial delay for a patent case with Endo Par Innovation Company over the drug.
Eagle received a complete response letter from the U.S. Food and Drug Administration (FDA), and after additional consultation with FDA, it has determined it will begin an additional, short-duration study by mid-March.
In the patent case, Eagle received word from the United States District Court for the District of Delaware last week its court data has been postponed to July 7, from February 1. According to the company, Endo Par has asserted claims in its patents for a vasopressin formulation with a pH between 3.7-3.9. However, Eagle says its vasopressin product would not be in that range.
Vasostrict – Endo Par’s branded version of injectable vasopressin – was approved in 2014 in hypotensive adult patients with vasodilatory shock, and works by increasing blood pressure. Vasopressin is a naturally occurring hormone and was previously marketed without FDA approval until 2011, when FDA required New Drug Applications (NDAs) from drugmakers. Endo Par was the first to win approval, and the company negotiated exclusive deals with the largest vasopressin suppliers, effectively blocking out existing competitors. At least one competitor, Fresnius SE, sued Endo over the moves but lost its case last year.
Eagle was the first of at least three companies that have submitted Abbreviated NDAs to FDA for approval of a generic vasopressin, and the complete response letter came following a priority review that was granted in November. The company said it has already met with FDA twice about the letter and “believes it can fully respond to the questions raised.” FDA and Eagle will meet again within a month.
Eagle estimates that Endo Par had over $700 million in sales for Vasostrict last year, up 20% over the previous year, and says FDA has flagged it as a COVID priority. Vasopressin has been used in adults with severe COIVD-19 with shock. If its Abbreviated NDA is approved, the company expects it will be eligible for a 180-day generic exclusivity period.