Bristol-Myers Squibb returns right for cancer drug candidate to Exelixis

California, USA-based drug developer Exelixis says it has regained full rights to develop and commercialize XL184 from partner US pharmaceutical major Bristol-Myers Squibb. The companies entered into a global development collaboration for XL184, the clinically most advanced MET inhibitor, in December 2008.

That deal involved an upfront payment to Exelixis of $195 million and could have generated a total to the company of at least $240 million from B-MS and, at the time, saw the developer's share price leap 33%.Yesteday's news saw Exelixis shares plunge 16% to $3.84.

Under the accord, B-MS and Exelixis had originally agreed to certain clinical development plans, and Exelixis maintained key rights regarding timing and funding of current and future clinical trials. Given the recent progress of B-MS' wholly-owned oncology pipeline and positive data generated by XL184, the two firms were not able to align on the scope, breadth and pace of the ongoing clinical development of XL184. As a result, B-MS returned XL184 to Exelixis, thereby giving the latter the opportunity to advance the program as originally envisioned. B-MS will make a payment to Exelixis of $17 million in connection with the return of the cancer drug candidate.