Astellas regains bladder drug from GSK

Astellas Pharma US has exercised its right under a 2003 co-promotion agreement with GlaxoSmithKline (GSK) to take back full commercial responsibility in the US for its overactive bladder treatment VESIcare (solifenacin succinate).

The companies have been co-promoting Vesicare in the US since the drug was launched in 2005. However, Astellas said it would now take over all promotional activities for the product and that GSK sales reps would no longer promote the drug. The change is expected to take place after a transition period that will end no later than January 2012.

Specific financial terms of the arrangement were not disclosed, but Astellas said it would make "certain payments" to GSK until 2015, when the co-promotion deal had been scheduled to conclude.

"GlaxoSmithKline has been an instrumental partner for Astellas in this successful co-promotion since the company first introduced Vesicare into the marketplace," the company said. "Astellas Pharma US will work with GlaxoSmithKline over the coming months to ensure a smooth and transparent transition."

Vesicare was the first product to be launched by Yamanouchi Pharma America, Japan-based Astellas' independent sales and marketing network in the US. The drug is among Astellas' top-selling products, with annual North American sales of about $431m. However, it is due to lose its patent protection in the US market in 2018.

To help mitigate the effects of generic competition for Vesicare, Astellas is developing a next-generation overactive bladder treatment called mirabegron, which the company filed for marketing approval in Japan in June 2010. The drug has a different mechanism of action than Vesicare and may produce fewer side effects.