DMD: Prosensa Pursuing Path Forward for Drisapersen

Update (May 1, 2014): For encouraging results from an open-label, extension study of drisapersen (all participants receive the drug in an open-label study), see Prosensa's May 1, 2014, press release. For additional information, listen to and view the webcast of the same date; and view the poster presented at the 66th annual meeting of the American Academy of Neurology, held in Philadelphia April 26-May 3, 2014. Nathalie Goemans from the University of Leuven in Belgium and a key investigator on various drisapersen studies, said, "We see very positive signs of the ability of drisapersen to improve the walking ability of boys with DMD. In this extension study, patients who entered the study with a less advanced stage of the disease either improved or experienced less decline in mobility with two-year continuous drisapersen therapy, and these data suggest a treamtnet difference from those initially on placebo."


original story:

Dutch biotechnology company Prosensa, developer of the experimental exon-skipping drug drisapersen for patients with Duchenne muscular dystrophy (DMD) who can be helped by skipping exon (section) 51 of the dystrophin gene, says it is actively working to determine a path forward for this drug.

MDA is not funding clinical trials of drisapersen at this time, but it has supported foundational research in exon skipping, the strategy used by Prosensa in developing this compound.

In an April 29, 2014, communication to patient groups, the company said it hopes to be able to relay information from regulators about drisapersen by the end of June 2014 and to resume dosing patients with drisapersen at study sites in North America and Europe by the third quarter of 2014.

Prosensa and its then-partner, GlaxoSmithKline (GSK), halted dosing with drisapersen in clinical trials in September 2013, after a large-scale, phase 3 trial of the drug conducted outside the United States found no statistically significant differences on tests of walking distance or motor function between treated and placebo participants.

In contrast, results from a U.S.-based, phase 2 trial of drisapersen, for which results were announced in March 2014, at the MDA Clinical Conference in Chicago, were more encouraging.

The April 29 communication, signed by Prosensa's chief medical officer Giles Campion and manager of patient group relations Claire Leyten, says, "We realize that this is a very difficult period for the boys and families, and we are working as quickly as possible to provide access to drisapersen and determine a path forward. As soon as we have concrete information on re-dosing, we will communicate our plans in a timely manner."

The company invites families to view and listen to a March 25, 2014, webinar that's archived on the Prosensa site under Events & Presentations.

Prosensa also will be making a presentation on April 30, 2014, at the American Academy of Neurology meeting in Philadelphia.

The company invites families to contact Claire Leyten at if they have questions.