FDA staffers cast doubts on Sanofi's pitch for key blood thinner

Sanofi's ($SNY) application for a new blood thinner--semuloparin--has run into some choppy waters at the FDA. Ahead of the June 20 panel meeting staffers concluded that the drug giant doesn't have the data needed for an approval to treat venous thromboembolism among chemo patients.

The problem for the FDA staffers, reports Reuters, is that most of the patients in the studies for the drug didn't have issues with clotting, instead dying from other causes. "These findings call into question the clinical value of semuloparin in the proposed clinical setting," concluded the review.

That's bad news for Sanofi, which has gone through a long dry spell on new drug approvals, despite bold plans to restructure its R&D operations. Bryan Garnier's Eric Le Berrigaud tells Bloomberg that the drug could bring in more than $600 million a year, if it can get an approval.

Semuloparin was one of 6 key drug programs singled out by Sanofi last fall. Sanofi also recently filed for an approval of Aubagio (teriflunomide) as well as the new MS drug Lemtrada. 

- here's the Bloomberg report
- here's the Reuters story