US company Oscient Pharmaceuticals looks likely to have failed in its bid to have the indications for its antibiotic Factive extended to include acute sinus infections in the USA, after a Food and Drug Administration advisory committee said yesterday its safety and efficacy had not been demonstrated.

Factive (gemifloxacin mesylate) is already approved for community-acquired pneumonia and chronic bronchitis but has already been turned down in 2000 by the FDA for the sinus indication, when the drug was in GlaxoSmithKline’s portfolio. Oscient booked $2.6 million from Factive sales in the second quarter of this year.

The FDA panel voted 11-2 that Factive’s efficacy in sinusitis did not outweigh certain safety issues, particularly a higher risk of rash and other dermatological reactions compared to other members of the fluoroquinolone antibiotic class.

While none of the rashes seen in patients taking the drug since it reached the market in 2004 were life threatening, there were concerns that they could reflect an elevated risk for the life-threatening dermatological reaction known as Stevens Johnson syndrome.

But there was also doubt about the drug’s efficacy relative to other antibiotics in sinusitis, and the panel also raised questions about the suitability of using ‘non-inferiority’ studies, which have fallen out of favour at the FDA for testing antibiotics against less serious infections like sinusitis.

Oscient is also trying to get approval for a five-day treatment regimen for Factive in pneumonia, but this was not covered at yesterday’s meeting.