By Mike Yamamoto, managing editor of OptionMonsterNEW YORK -- Bullish option traders are piling into Valeant Pharmaceuticals ( VRX) as its shares reach all-time highs. OptionMonster's tracking systems detected the purchase of about 2,100 October 105 calls Thursday, led by a large print of 1,355 contracts that went for $3.35. Volume was more than nine times the previous open interest at the strike, indicating that this is fresh buying. Calls lock in the price where shares can be purchased, offering potentially significant leverage in a rally. Investors also use these options to limit the amount of capital at risk if the shares reverse lower. But the Valeant calls bought Thursday will expire worthless in mid-October if the stock remains below the $105 strike price. Valeant's shares rose 4.19% to $101.68 on Thursday, a new closing high. The stock had spent most of June at support around $84 but then started moving last month and gained 2% on Wednesday as strong demand in emerging markets prompted management to raise guidance. Total option volume in the session was more than triple its daily average for the last month, with overall calls leading puts by 4,200 to 1,700. Yamamoto has no positions in VRX.