Vivus, which has been the subject of frenzied takeover talk since advisors to the US Food and Drug Administration backed its obesity drug Qnexa, has launched a public offering aimed at raising $202.5 million.

The firm is putting up 9 million shares priced $22.50 per share and the offering is expected to close on March 6. Vivus has also granted the underwriters an option to purchase up to nearly 1.4 nillion additional shares.

The proceeds will be primarily used to fund a sales force and the production of promotional materials necessary to commercialize Qnexa (phentermine/topiramate), which last month got the backing of the FDA's Endocrinologic and Metabolic Drugs Advisory Committee. Cash will also be used to support non-US marketing approvals for Qnexa and Vivus' impotence drug avanafil.

Simos Simeonidis, an analyst at Cowen & Co, said the offering is a "prudent and conservative move for the company to take advantage of the substantial move in the stock to significantly strengthen the balance sheet". He added that should Qnexa be approved by April 17, "there will be an additional move to the stock, and we expect that the company could tap the capital markets again…in order to improve its negotiating position with big pharma partners/potential acquirers".