Cabozantinib – Top 10 Late-Stage Cancer Drugs – 2012


Developer: Exelixis
Partner: Exelixis and Bristol-Myers Squibb ended partnership in 2010
Lead indication: Thyroid cancer (but prostate is the big opportunity)
Key date: Phase III Comet-1 study begins 1H 2012

Exelixis ($EXEL) failed to get the FDA to support the design of its Phase III program for cabozantinib in castrate-resistant prostate cancer, but the drug remains one of the hot experimental cancer drugs in biopharma today. And the positive late-state trial data for the drug in thyroid cancer last year bodes well for the drug's approval in that smaller market this year.

Exelixis surprised and disappointed some investors last year with its plans to move ahead with its Phase III program for "cabo" without a special protocol assessment from U.S. regulators. The South San Francisco-based developer has made pain response and impact on bone scans the main goals its Phase III trial known as COMET-2, yet several existing drugs for prostate cancer have established survival benefits, JPMorgan analyst Cory Kasimov has noted. The company does plan to pursue survival endpoints for "cabo" in prostate cancer in its COMET-1 study, which is expected to begin in the first half of this year.

Prostate cancer offers the biggest market opportunity for cabo, but investors are going to have to wait until 2014 for survival data in patients with aggressive, castrate-resistant disease. At least Kasimov believes that survival data are important in determining how well cabo will fair in the increasingly competitive market for prostate cancer drugs.

In the meantime, the team at Exelixis is determined to prove that its drug does offer a differentiated option for treating prostate cancer. And CEO Mike Morrissey led a restructuring at the company last year to focus the company's resources on its lead candidate, laying off workers and casting other R&D projects aside in the process.