Options traders have set their sights on VIVUS, Inc. (NASDAQ:VVUS - 20.95) today, especially on the bearish side of the tape. In afternoon trading, the drug maker has seen roughly 10,000 puts and 9,200 calls change hands, compared to its average intraday volume of around 1,100 puts and 2,200 calls.

Digging deeper, it seems speculators are initiating new positions at the soon-to-be front-month October 18 and 21 puts, which have each seen around 1,500 contracts traded. Volume has exceeded open interest at both strikes, and the majority of the puts have crossed at the ask price, hinting at buy-to-open activity.

The volume-weighted average price (VWAP) of the 18-strike puts is $0.37, meaning the buyers will profit if VVUS breaches the $17.63 level (strike minus premium paid) within the next month or so. Meanwhile, the October 21 puts changed hands for a VWAP of $1.35, pointing to a breakeven level of $19.65 on the trade.

While the shares of VVUS haven't yet hit either level today, it hasn't been for lack of trying. The stock has bucked the broad-market trend higher, shedding more than 11.7% to hit an intraday nadir of $20.35. Investors are undoubtedly responding to the company's warning that European regulators are unlikely to recommend marketing approval for its obesity drug next month -- which could delay Qsiva's (known as Qsymia in the U.S.) entry into the European market by at least a year, according to some analysts.

The news, as well as VVUS' subsequent plunge, may be spooking a few options traders. Despite today's appetite for bearish bets, investors have been scooping up VVUS calls over puts at a much faster-than-usual clip during the past couple of weeks. In fact, the stock's 10-day call/put volume ratio on the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX) stands at 7.22, higher than 88% of all other readings of the past year.

Elsewhere, a few analysts might also be reconsidering their optimistic stances on VVUS. Currently, the stock boasts six "buy" or better ratings, compared to four lukewarm "holds" and just one "sell" or worse suggestion. Plus, the average 12-month price target stands at $37.50 -- implying expected upside of 84% to VVUS' intraday low today, and in territory the security hasn't charted since late 1997.

Should European regulators deny Qsiva in mid-October, an unwinding of optimism in the options arena, or a flood of negative analyst attention, could exacerbate VVUS' slide.

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