Shares of Onyx Pharmaceuticals Inc. have hit a 52-week high on the Nasdaq Monday morning after the drug developer's Nexavar treatment, co-developed by Bayer AG, was hailed as a breakthrough drug for improving the survival of people with liver cancer, a hard-to-treat disease. The drug, already approved for kidney cancer, extended patient survival by nearly three months in a large clinical trial, which cancer specialists said represents a breakthrough in treatment. The stock is trading at $32.92 (U.S.), up $2.04 or 6.8 per cent, after hitting a new high of $34 on volume topping 8 million shares. Bear Stearns has upgraded the stock to "outperform" from "peer perform," with a $40 price target.