French drugmaker Ipsen has picked up rights to Exelixis’ lead oncology drug cabozantinib in deal worth up to $855 million plus potential royalties.

The deal sees Ipsen gain exclusive commercialisation rights for current and potential future cabozantinib indications outside the US, Canada and Japan, including Cometriq, which is cleared in the EU for the treatment of adult patients with progressive, unresectable, locally advanced or metastatic medullary thyroid cancer. 

In return, Exelixis gets a $200 million upfront payment and stands to receive regulatory milestones, including a $60 million milestone upon approval of cabozantinib in Europe for advanced renal cell carcinoma (RCC), and $50 million upon the drug’s filing and approval in the region for advanced hepatocellular carcinoma (HCC), as well as additional regulatory milestones for potential further indications. 

The agreement also includes up to $545 million of potential commercial milestones and provides for Exelixis to receive tiered royalties up to 26% on Ipsen’s net sales of cabozantinib in its territories.

“Cabozantinib has the potential to become a key oncology product,” said Marc de Garidel, Ipsen’s chairman and chief executive, explaining the firm’s interest in the deal. “This transaction will help Ipsen accelerate the growth of the company and strengthen its oncology footprint in Europe.”

The immediate priority for the drug is on advanced RCC, but the firms said they are also committed to exploring and potentially developing cabozantinib in a variety of cancer settings. The drug suffered a high profile failure in a Phase III prostate cancer trial back in 2014, but has been making a comeback ever since.