Pozen shares slide after FDA questions study for aspirin combo

FDA regulators have unexpectedly blocked--at least temporarily--Pozen's path to a regulatory approval of its amped up and extra-safe combo aspirin. And it may have to set up an in vivo bioequivalence study in order to make its case.

Just three months after offering positive top-line Phase III data on PA32540, its combo of immediate-release omeprazole and a 325 mg dose of delayed-release aspirin designed to prevent ulcers among high-risk cardio patients, the biotech announced that regulators aren't happy with the company's early-stage bioequivalence study. Investors hate that kind of nasty surprise, and Pozen's shares ($POZN) tanked, sliding 16% on the news.

"Based on its preliminary assessment, the FDA does not agree that bioequivalence of PA32540 to EC aspirin 325 mg was demonstrated based on the information available to the FDA at this time," the company stated in a release this morning. "The FDA indicated that the reference-scaled bioequivalence approach used in the 115 Study was justifiable for PA32540 in establishing bioequivalence with EC aspirin 325 mg with ASA as the analyte."

FDA also advised Pozen that, "as a general comment, for the development of a combination product with 81 mg aspirin, an in vivo bioequivalence study will be necessary unless a biowaiver can be further justified." 

Last March company CEO John R. Plachetka said the Chapel Hill, NC-based biotech would file for an approval in the third quarter as it advanced partnership talks. Their next step now is to follow up with a meeting at the FDA. 

- read the press release
- here's the story from Reuters