Investor raises stake in Onyx Pharma

Onyx Pharmaceuticals has been running, and one investor is looking for gains to accelerate this week.

optionMONSTER's Heat Seeker tracking program detected the purchase of 1,500 September 80 calls for $3 and the sale of 1,000 September 77.50 calls for $4.85. Volume was below open interest in the 77.50s, indicating that an existing long position was closed and rolled to the higher strike.

The move is noteworthy because it increased the number of long calls in the position, which will provide additional leverage in the event of a sharp move into expiration this Friday. The trader also collected a credit of $35,000. (See our Education section)

ONXX is up 1.77 percent to $82.70 in late morning trading and is now at its highest prices ever. The stock has more than doubled in the last six months, with much of that move coming on June 21 after a Food and Drug Administration advisory panel voted in favor of approving its carfilzomib blood-cancer treatment.

Overall option volume is quadruple the daily average so far today, with calls outnumbering puts by more than 2 to 1.

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