ImClone Systems' (NASDAQ:IMCL) stock price has been all over the place this year, falling as low as $26 and rising as high as $45 a share. Even with a volatile stock, one thing ImClone has been consistent with is advancing its drug candidates through the pipeline.

ImClone announced yesterday that it was beginning phase 2 testing of an anti-insulin-like growth factor-1 receptor monoclonal antibody (try saying that three times fast) as a treatment for late stage metastatic prostate cancer. The trial will be a small, 30-person study testing the drug's efficacy and safety.

ImClone also initiated a phase 2 study of its vascular endothelial growth factor receptor (VEGFR) inhibitor last week. It will be tested as a treatment for metastatic kidney cancer in patients who have failed with other VEGF inhibitors, presumably Pfizer's (NYSE:PFE) Sutent or Onyx Pharmaceuticals' (NASDAQ:ONXX) and Bayer's (NYSE:BAY) Nexavar.

ImClone's anti-VEGFR compound, thoughtfully named IMC-1121B, will be tested on a range of tumors in the coming months. Like most inhibitors of the VEGF protein, success in the kidney cancer study likely will mean that the drug can be used to fight the growth of other cancers as well, which makes this kidney cancer study so important to ImClone.

Many investors give ImClone credit only for its marketed antibody Erbitux. Any setback or success with Erbitux tends to send shares of ImClone flying. With three new molecules in phase 2 testing and another two in phase 1 testing by the end of the year, ImClone may not be completely reliant on Erbitux for its fortunes in the coming years.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool has a disclosure policy.