Top-line results from Exelixis' cabozantinib phase 3 trial on medullary thyroid cancer

Exelixis, Inc. (NASDAQ:EXEL) today reported top-line results from the ongoing phase 3 clinical trial of cabozantinib in patients with advanced medullary thyroid cancer (MTC), known as the EXAM trial. The trial met its primary endpoint of improving progression-free survival (PFS) compared with placebo and substantially exceeded the threshold of a 75% increase in PFS originally assumed when the trial was designed. Cabozantinib significantly improved median PFS by 7.2 months compared with placebo. The median PFS on the cabozantinib arm was 11.2 months versus 4.0 months on the placebo arm; hazard ratio (HR) 0.28, (95% CI 0.19, 0.40), p < 0.0001. Exelixis intends to report the EXAM data at an upcoming medical conference.

"The success of the EXAM trial is an important advance for MTC patients and for Exelixis," said Michael M. Morrissey, Ph.D., president and chief executive officer of Exelixis. "These data demonstrate cabozantinib's profound anti-tumor activity in an indication that has seen little clinical progress over the past few decades. They also highlight Exelixis' late-stage clinical development capabilities that will continue to be of critical importance as cabozantinib advances through late-stage development in other indications. Potential approval of cabozantinib in MTC would be a first step to achieve our goal of improving the lives of cancer patients, and would set a solid foundation on which to build a cabozantinib franchise that includes large indications such as prostate cancer."

Exelixis will consult with the FDA to determine whether the trial conduct should be changed as a result of these data in conjunction with the SPA. The company is requesting permission to begin a rolling submission of the New Drug Application (NDA) for cabozantinib in this indication to the U.S. Food and Drug Administration (FDA). It is anticipated that the filing will be completed in the first half of 2012.

"The prospect of a new highly effective therapy for MTC gives patients and physicians a reason for great optimism," said Steven I. Sherman, M.D., Chair and Naguib Samaan Distinguished Professor in Endocrinology and Medical Director, Endocrine Multidisciplinary Center at MD Anderson Cancer Center, who was also an investigator in the study. "Personally, as a clinician who treats many patients with advanced MTC, it is particularly gratifying to see Exelixis' commitment to the thorough evaluation of cabozantinib in this indication in a large phase 3 study, and the resultant positive outcome of the trial. This represents important progress in the treatment of MTC, an indication that has long been underserved and still has a significant unmet medical need. I believe that cabozantinib has great potential to improve the care and outcomes of MTC patients."