Bristol-Meyers Squibb (BMY) announced this morning that it was buying heart drug developer MyoKardia Inc (Nasdaq: MYOK) for $13 billion, or $225 per share in cash, as a way to boost its portfolio of heart disease treatments. The shares of MYOK are trading at a record high in response, up 58.3% at $220.92 at last check. 

This isn't the first major move MYOK has made in the past year. The stock enjoyed a massive bull gap in mid-May, grabbing several consecutive record highs in the following sessions. Though MYOK cooled after a brush with the $110 level, support at its 80-day moving average helped push the security past this range, and on to even more fresh highs in late September and early October. Now, MYOK boasts an impressive 203.1% year-to-date lead. 

The typically quiet options pits are going wild today as a result, and its bears are taking the lead. So far, 781 calls and 3,555 puts have exchanged hands -- 54 times the intraday average. The monthly October 200 put is the most popular, followed by the March 210 put. It appears that positions are being bought to open at both, suggesting these bears are betting on MYOK stock pulling back a bit in the coming months. 

This is a shift from the norm, as MYOK sports a 50-day call/put volume ratio of 7.36 at the International Securities Exchange (ISE), Cboe Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX). This ratio stands higher than 87% of readings from the past year, suggesting a healthier-than-usual appetite for long calls.