GlaxoSmithKline is linking up with Prosensa to develop drugs for Duchenne muscular dystrophy, an agreement that could be worth £428 million to the Dutch biopharmaceutical company.

Under the terms of the deal, GSK has acquired the rights to develop and sell Prosensa’s lead compound, PRO051, an RNA modulating therapeutic which acts by skipping exon 51 of the dystrophin gene. Three other RNA-based compounds, which seek to treat “specific, but different, subpopulations of patients suffering from DMD,” are covered by the agreement.

Cashwise, GSK is making an upfront payment of £16 million and Prosensa is eligible to receive up to £412 million in milestones if all four compounds are successfully developed. The Leiden-headquartered firm is also entitled to double-digit royalties on product sales and will retain certain commercial participatory rights.

DMD is a severely debilitating neuromuscular disease that affects one in 3,500 newborn boys. Patients suffer from progressive loss of muscle strength due to the absence of the protein dystrophin, often making them wheelchair-bound before the age of 12, and most die in early adulthood due to respiratory and cardiac failure.

Hans Schikan, Prosensa’s chief executive, said that the alliance will not only speed-up the further development of PRO051, “but will also accelerate the progress of our complementary DMD therapeutics, allowing us to reach a broader patient population”. The deal comes a month after GSK’s R&D chief Moncef Slaoui revealed that the that company was looking to expand into the orphan drugs market.

Meantime, GSK has entered into a partnership with the UK Government, the Wellcome Trust and the East of England Development Agency to develop a biotechnology science park located at the company’s site in Stevenage. Full details in tomorrow’s PharmaTimes UK News elert.