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FDA Issues Response to BioMarin’s DMD Treatment

Press Release: FDA Issues Complete Response Letter for KyndrisaTM for Duchenne Muscular Dystrophy Amenable to Exon 51 Skipping

Summary: BioMarin reported today that it has received a Complete Response Letter from the U.S. Food and Drug Administration (FDA) indicating that the review cycle for the company’s New Drug Application for drisapersen (Kyndrisa) to treat DMD is complete and that the application is not ready for approval in its present form as the standard of substantial evidence of effectiveness has not been met. BioMarin is reviewing the Complete Response Letter and will work with the FDA to determine the appropriate next steps regarding this application while the marketing authorization application remains under regulatory review in Europe. BioMarin said that extension studies for drisapersen will continue, as will ongoing studies for other exon-skipping therapies targeting exons 44, 45 and 53, while it explores next steps for this application.

Statement from MDA Executive Vice President & Chief Medical and Scientific Officer Valerie Cwik, M.D.: “Our families urgently need safe and effective treatments, and although this is not the outcome so many had hoped for, we know that the FDA exercised its due diligence in considering drisapersen.

We commend the remarkable strength of our community and we are proud to have worked together to reach a point where experimental therapies like drisapersen are moving through the regulatory review process. As our community moves forward, we will continue to fund critical scientific research, facilitate clinical trial participation, and advocate for policies that help ensure that the drug development and regulatory review processes move as quickly and effectively as possible.

With more treatments staged to begin their review process in 2016, we remain optimistic that many of those living with DMD today will have safe and effective therapy options in the very near future. MDA families, we will continue to do everything in our power to advocate on your behalf.”

Background: Drisapersen is an "exon-skipping" drug that targets a section of the dystrophin gene called exon 51, and may help up to 13 percent of DMD patients. Exon skipping is a treatment strategy in which sections of genetic code are “skipped,” allowing the creation of partially functional dystrophin, the muscle protein missing in DMD. Exon skipping is not a cure for DMD, but could lessen the severe muscle weakness and atrophy that is the hallmark of this disease.

MDA has funded groundbreaking DMD research for over 60 years, including laboratory development of exon skipping since the 1990s, and today provides coordinated multidisciplinary care to those living with DMD in our more than 150 clinics nationwide.