Takeda Pharmaceutical Co has signed a deal to develop and sell Orexigen Therapeutic's investigational obesity drug Contrave.

The deal, which covers rights to Contrave (sustained-release naltrexone/bupropion) in the USA, Canada and Mexico, will see Orexigen get an upfront fee of $50 million from Takeda, and it will be eligible to receive payments of over $1 billion upon achieving certain regulatory and sales-based milestones. The Japanese firm will also pay tiered double-digit royalty payments on net sales.

The Contrave combo is "believed to address both biological and behavioural drivers of obesity", the new partners noted, "controlling the balance of food intake and metabolism, and regulating reward-based eating". It will go in front of a US Drug and Administration advisory panel on December 7 and has a Prescription Drug User Fee Act action date of January 31, 2011.

Shinji Honda, head of Takeda in North America, said his firm has "deep experience in providing important medicines to treat chronic disease and Contrave will help us provide a full spectrum of treatment to patients for the management of obesity." Orexigen chief executive Michael Narachi said that "this is a great strategic partnership to enable our goal of a strong market entry for Contrave, if approved".

He added that "it has been our belief that getting a partner involved early would be critical to a high-quality launch of Contrave, and with this partnership now in place, we are tightly focused on the regulatory review process and securing approval".

This are interesting times in terms of new obesity drugs and Orexigen is one of a trio of companies looking to impress the US Food and Drug Administration. In July, the agency's Endocrinologic and Metabolic Drugs Advisory Committee voted against backing Vivus' Qnexa (phentermine/topiramate) over long-term safety concerns, while Arena Pharmaceuticals’ lorcaserin is due to go in front of an FDA panel on September 16. Interestingly, Arena has also partnered with a Japanese drugmaker, Eisai.