Prosensa Reports Initial Findings from the Further Clinical Data Analyses of Drisapersen for the Treatment of Duchenne Muscular Dystrophy

Corporate update presentation given at the 32nd Annual J.P. Morgan Healthcare Conference in San Francisco on Thursday, January 16, 2014 at 10:00 AM Pacific Time


Leiden, The Netherlands, Jan. 16, 2014 (GLOBE NEWSWIRE) -- Prosensa Holding N.V. (NASDAQ: RNA), the Dutch biopharmaceutical company focusing on RNA-modulating therapeutics for rare diseases with high unmet medical need, today announced initial findings from further analyses from the aggregate data from the clinical development program of drisapersen for the treatment of Duchenne Muscular Dystrophy (DMD).

"We are encouraged by these results that suggest that treating earlier in the disease and treating longer shows a delay in the progression of the disease," said Hans Schikan, Prosensa's Chief Executive Officer. "These data encourage us to engage patient groups, clinical experts and regulators to explore a path forward for drisapersen, which includes the possibility of re-dosing."

Schikan will be presenting details of the further data analyses at the 32nd Annual J.P. Morgan Healthcare Conference in San Francisco on Thursday, January 16, 2014 at 10:00 AM Pacific Time. A live webcast of the presentation can be accessed through the Investors & Media section of the Prosensa corporate website at http://ir.prosensa.eu/events.cfm  and will be archived for 90 days.

With data from more than 300 patients Prosensa has the largest clinical data set in DMD. In order to advance the general understanding of DMD, Prosensa has also announced that it will make certain data from the drisapersen clinical program available to the scientific community. In addition it has initiated a study to better understand the natural history of DMD and is also exploring potential biomarkers that could be of use as indicators of efficacy in DMD clinical trials.

The subset analyses focus on outcomes in DMD boys seven years or younger and those over seven years old as measured by the six-minute walk test (6MWT). In all studies, a treatment difference was seen in the younger patient population.

Notably, the preliminary analysis of the 96 week extension data from those participating in the phase III DMD114044 (DEMAND III) study shows a 49 meter difference between those on continual treatment (n=52) and those who had been on placebo for 48 weeks followed by active drug (n=31).  Those previously participating in the DMD114117 study (DEMAND II) showed a 52 meter difference at 96 weeks (n=13, n=17, respectively).

Key safety findings are consistent with previous observations, including injection site reactions, proteinuria and mild to severe thrombocytopenia.

Schikan concludes, "We will continue to work closely with patient groups, clinical experts and regulators to ensure that we leave no stone unturned to bring treatments to boys affected by DMD."

About drisapersen and the clinical development program

Drisapersen, (previously GSK2402968/PRO051), an antisense oligonucleotide which induces exon skipping of exon 51, is currently in-late stage development for DMD. Drisapersen has orphan drug status in the EU, US, Australia and Japan. In June 2013, drisapersen was granted Breakthrough Therapy designation by the US Food and Drug Administration.

The overall drisapersen clinical program comprises three double-blind, placebo-controlled studies (DMD114117, DMD114876 and DMD114044) and two long term open-label extension studies (DMD114673 and DMD114349).

For more information regarding the ongoing clinical studies involving drisapersen visit www.clinicaltrials.gov.

About DMD

Duchenne Muscular Dystrophy (DMD) is a severely debilitating childhood neuromuscular disease that affects up to 1 in 3,500 live male births. This rare disease is caused by mutations in the dystrophin gene, resulting in the absence or defect of the dystrophin protein. Patients suffer from progressive loss of muscle function, often making them wheelchair bound before the age of 12. Respiratory and cardiac muscle can also be affected by the disease. Few patients survive the age of 30.

About exon skipping

The dystrophin gene is the largest gene in the body, consisting of 79 exons. Exons are small sequences of genetic code which lead to the manufacture of sections of protein. In DMD, when certain exons are mutated/deleted, the RNA cannot read the genetic code past the fault. This prevents the rest of the exons being read, resulting in a non-functional dystrophin protein and the severe symptoms of DMD.

RNA-based therapeutics, specifically antisense oligonucleotides inducing exon skipping, are currently in development for DMD. This technology uses synthetic antisense oligonucleotides to skip an exon next to a deletion and thereby correct the reading frame, enabling the production of a novel dystrophin protein. Up to 13% of boys with DMD have dystrophin gene mutation/deletions amenable to an exon 51 skip.

About Prosensa Holding N.V.

Prosensa (NASDAQ: RNA) is a Dutch biotechnology company engaged in the discovery and development of RNA-modulating therapeutics for the treatment of genetic disorders. Its primary focus is on rare neuromuscular and neurodegenerative disorders with a large unmet medical need, including Duchenne muscular dystrophy, myotonic dystrophy and Huntington's disease.

www.prosensa.com

Forward Looking Statements

This press release contains certain forward-looking statements.  All statements, other than statements of historical facts, contained in this press release, including statements regarding our strategy, future operations, future financial position, future revenues, projected costs, prospects, plans and objectives of management, are forward-looking statements. The words "anticipate," "believe," "estimate," "expect," "intend," "may," "plan," "predict," "project," "target," "potential," "will," "would," "could," "should," "continue," and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Forward-looking statements in this press release include statements around our exon -skipping drug candidates. Actual results may differ materially from those projected or implied in such forward-looking statements. Such forward-looking information involves risks and uncertainties that could significantly affect expected results.  These risks and uncertainties are discussed in the Company's SEC filings, including, but not limited to, the Company's Form 6-K containing this press release and certain sections of the Company's Registration Statement on Form F-1. In addition, any forward-looking statements represent our views only as of today and should not be relied upon as representing our views as of any subsequent date. While we may elect to update these forward-looking statements at some point in the future, we specifically disclaim any obligation to do so, even if our views change.



            

Contact Data