Exelixis (EXEL) faces limited high-impact catalysts, and the opportunity from potential success with the zanza trials is already priced into the valuation, BofA Securities said in a Monday note.

Analysts said that the company's Cabometyx cancer drug has limited patent life, with exclusivity set to expire by 2031.

BofA said that since phase 3 data from its trial evaluating zanza in colorectal cancer was "relatively underwhelming," it expects only niche peak sales of around $300 million.

Analysts said that updates from competitors could weigh on Exelixis shares, notably from Merck (MRK), which could erode Cabometyx's market position.

BofA downgraded the stock's rating to underperform from neutral and lowered its price target to $41 from $43.

Exelixis shares were down 3% in recent Monday trading.

Price: 42.12, Change: -1.46, Percent Change: -3.35