BioMarin Pharmaceutical has announced the acquisition of Huxley Pharmaceuticals, manufacturers of 3,4-diaminopyridine (3,4-DAP), a new treatment for the rare autoimmune disease Lambert-Eaton myasthenic syndrome (LEMS).

The new treatment recently received a positive opinion from the EU Committee for Medicinal Products for Human Use and if approved, would become the first LEMS treatment, winning ten years of European market exclusivity.

BioMarin CEO Jean-Jacques Bienaime said that this deal leverages existing European infrastructure and commercial capabilities and provides opportunities for near-term revenue growth and operating income growth.

“We expect to launch the product in Europe in the first quarter of 2010, and are evaluating the best development strategy for amifampridine phosphate in LEMS in the US and in other indications in the US and Europe,” Bienaime said.

“We will also evaluate the development of amifampridine phosphate in other indications including multiple sclerosis.”

Under the acquisition, BioMarin paid Huxley stockholders $15m upfront and will pay an additional $7.5m on final approval of amifampridine, which is expected in late 2009 or early 2010.

Huxley stockholders will also be eligible to receive up to $36m in milestone payments based on annual cumulative sales and meeting US development milestones.

Huxley licensed the rights to 3,4-DAP from EUSA Pharma, which developed the product after acquiring the rights from the original developer, Assistance Publique Hopitaux de Paris.