GW Pharmaceuticals has reacquired full ownership of US rights to its cannabinoid medicine Sativex following the termination of a previous license agreement with Otsuka.

GW and Otsuka originally signed a licensing agreement in 2007 giving the latter an exclusive license to develop and market Sativex in the US.

The new arrangement gives GW the right to develop and commercialise the product in the US without having to make an upfront payment to the Japanese drugmaker.

The company will, however make contingent milestone payments to Otsuka, the first of which would become due upon FDA approval of Sativex, with following payments released on the achievement of certain annual US sales thresholds.

“We are pleased to have amicably reached this agreement with Otsuka, which enables GW to develop, seek approval for, and commercialise Sativex in the United States,” said Justin Gover, GW’s chief exeutive.

“We have previously conducted several positive Phase II and III trials for Sativex and believe that this product represents an important new late-stage pipeline opportunity for GW in the US market.”

Sativex is an oromucosal spray of a formulated extract that contains cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) in a 1:1 ratio.

The product is already cleared for use to treat spasticity in patients with multiple sclerosis in 29 countries outside of the US.