Stifel Nicolaus initiated its coverage of AVEO Pharmaceuticals (NASDAQ: AVEO) last week with a sell, which led to a 13% plunge in AVEO's share prices in a single day, citing concerns over the company's drug Tivozanib. Now, the company is rebounding, but it may have a long road ahead. Tivozanib recently beat Onyx's (NASDAQ: ONXX) Nexavar in a phase 3 trial as far as overall survival for renal cell carcinoma, and the company hopes to launch the drug in 2014, if it is approved. But Stifel thinks approval is unlikely, and even if it does get approved, this is already a crowded space, with a lot of competition.

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