After the successful conclusion of talks with the US Food and Drug Administration, Vivus has resubmitted its previously-rejected obesity treatment Qnexa for approval.

The decision follows an agreement reached last month with officials of the agency's Endocrine and Metabolic Division on the filing strategy for Qnexa (phentermine/topiramate). The FDA issued a complete response letter for the drug last October, citing concerns about potential side effects such as depression, memory loss, increased heart rate and birth defects.

Then in December, Vivus submitted a briefing document to the agency addressing the various concerns it had with the New Drug Application and last month, the firm noted its intention to refile. The latest submission includes a contraindication "for women of childbearing potential" and a risk evaluation and mitigation strategy.

The filing comes prior to completion of the FORTRESS study looking at topiramate's and Qnexa’s teratogenic potential, top-line results from which are expected in December. The resubmission will also allow for an early 2012 advisory committee meeting and a second-quarter 2012 prescription drug user fee act (PDUFA) action date. If the FORTRESS study is favourable, that may enable Vivus to expand the indication to include obese women of child-bearing age.

Shares in Vivus rose on the possibility that the firm has moved ahead of rival obesity drugs that have also been rejected by the FDA and could be resubmitted fairly soon - Orexigen Therapeutics' Contrave (naltrexone/bupropion) and Arena Pharmaceuticals/Eisai's lorcaserin. No prescription weight-loss pill has made it onto the US market since the launch of Roche's Xenical (orlistat) in 1999.