GSK returns IPX066 rights to Impax; Merck & Co and Pfizer link up on diabetes drug

US biotech firm Impax Laboratories (Nasdaq: IPXL) saw its shares fall 2% to $17.32 in premarket trading, after the company revealed the termination of its collaboration with UK pharma giant GlaxoSmithKline (LSE: GSK for the development and commercialization of IPX066 outside the USA and Taiwan has been terminated.

IPX066 (known as Rytary in the USA) is an investigational extended-release capsule formulation of carbidopa-levodopa being developed for the symptomatic treatment of adult patients with idiopathic Parkinson’s disease and is not approved anywhere in the world.

Under the terms of the accord entered into in December 2010, GSK’s right to develop and commercialize IPX066 outside the US and Taiwan will transfer back to Impax effective at the end of July 2013. The decision has been reached because of delays in the anticipated regulatory approval and launch dates in countries in which GSK has rights to commercialize the product. Impax intends to initiate activities to find a partner or partners for markets outside the U.S. looking to grow their non-US neurology franchise.