BioMarin Initiates Phase 3 Trial for Amifampridine Phosphate for the Treatment of LEMS

NOVATO, Calif., June 7, 2011 /PRNewswire/ -- BioMarin Pharmaceutical Inc. (Nasdaq: BMRN) announced today that the first patient has been dosed in the Phase 3 trial for amifampridine phosphate (3,4-diaminopyridine phosphate) for the treatment of patients with Lambert-Eaton Myasthenic Syndrome (LEMS).  Amifampridine phosphate received marketing approval in the EU for the treatment of LEMS in January 2010.  

"In early 2010, we introduced the first approved therapeutic option to the EU to treat LEMS, a rare, serious and debilitating disease.  We are conducting this Phase 3 trial to meet the regulatory requirements of the FDA in order to gain marketing authorization in the U.S. and are evaluating different commercialization options in the meantime," said Jean-Jacques Bienaime, Chief Executive Officer of BioMarin.  "This marks the fourth clinical trial initiated in 2011 as we remain committed to the advancement of our pipeline over the next few years."  

The Phase 3 trial is a double-blind, placebo-controlled randomized discontinuation study followed by an open-label extension period in approximately 30 patients across 25 sites worldwide.  The purpose of the study is to evaluate the efficacy and safety, including the long-term safety, of amifampridine phosphate.  The primary efficacy variable is the Quantitative Myasthenia Gravis score, and the secondary efficacy variable is the timed-25-foot walk test.  

About LEMS

Lambert-Eaton Myasthenic Syndrome (LEMS) is a rare autoimmune disease with the primary symptoms of muscle weakness. Muscle weakness in LEMS is caused by autoantibodies to voltage gated calcium channels leading to a reduction in the amount of acetylcholine released from nerve terminals. The prevalence of LEMS is estimated at four to ten per million, or approximately 2,000 to 5,000 patients in the EU and 1,200 to 3,100 patients in the U.S. Approximately 50 percent of LEMS patients diagnosed have small cell lung cancer.

Patients with LEMS typically present with fatigue, muscle pain and stiffness. The weakness is generally more marked in the proximal muscles particularly of the legs and trunk. Other problems include reduced reflexes, drooping of the eyelids, facial weakness and problems with swallowing. Patients often report a dry mouth, impotence, constipation and feelings of light headedness on standing. On occasion these problems can be life threatening when the weakness involves respiratory muscles.  A diagnosis of LEMS is generally made on the basis of clinical symptoms, electromyographic testing and the presence of autoantibodies against voltage gated calcium channels.

About BioMarin

BioMarin develops and commercializes innovative biopharmaceuticals for serious diseases and medical conditions. The company's product portfolio comprises four approved products and multiple clinical and preclinical product candidates. Approved products include Naglazyme® (galsulfase) for mucopolysaccharidosis VI (MPS VI), a product wholly developed and commercialized by BioMarin; Aldurazyme® (laronidase) for mucopolysaccharidosis I (MPS I), a product which BioMarin developed through a 50/50 joint venture with Genzyme Corporation; Kuvan® (sapropterin dihydrochloride) Tablets, for phenylketonuria (PKU), developed in partnership with Merck Serono, a division of Merck KGaA of Darmstadt, Germany; and Firdapse™ (amifampridine), which has been approved by the European Commission for the treatment of Lambert-Eaton Myasthenic Syndrome (LEMS). Product candidates include GALNS (N-acetylgalactosamine 6-sulfatase), which is currently in Phase III clinical development for the treatment of MPS IVA, amifampridine phosphate (3,4-diaminopyridine phosphate), which is currently in Phase III clinical development for the treatment of LEMS in the U.S., PEG-PAL (PEGylated recombinant phenylalanine ammonia lyase), which is currently in Phase II clinical development for the treatment of PKU, BMN-701, a novel fusion protein of insulin-like growth factor 2 and acid alpha glucosidase (IGF2-GAA), which is currently in Phase I/II clinical development for the treatment of Pompe disease, and BMN-673, a poly ADP-ribose polymerase (PARP) inhibitor, which is currently in Phase I/II clinical development for the treatment of genetically-defined cancers. For additional information, please visit www.BMRN.com. Information on BioMarin's website is not incorporated by reference into this press release.

Forward-Looking Statement

This press release contains forward-looking statements about the business prospects of BioMarin Pharmaceutical Inc., including, without limitation, statements about: the expectations of the development of amifampridine phosphate, including the timing of the clinical trials of the candidate, and the possible efficacy of such candidate. These forward-looking statements are predictions and involve risks and uncertainties such that actual results may differ materially from these statements. These risks and uncertainties include, among others: the content and timing of decisions by the U.S. Food and Drug Administration, the European Commission and other regulatory authorities, results and timing of current and planned clinical and preclinical studies related to such product; our ability to successfully manufacture the product; and those factors detailed in BioMarin's filings with the Securities and Exchange Commission, including, without limitation, the factors contained under the caption "Risk Factors" in BioMarin's 2010 Annual Report on Form 10-K, and the factors contained in BioMarin's reports on Form 10-Q. Stockholders are urged not to place undue reliance on forward-looking statements, which speak only as of the date hereof. BioMarin is under no obligation, and expressly disclaims any obligation to update or alter any forward-looking statement, whether as a result of new information, future events or otherwise.

BioMarin®, Naglazyme®, Kuvan® and Firdapse™ are registered trademarks of BioMarin Pharmaceutical Inc.

Aldurazyme® is a registered trademark of BioMarin/Genzyme LLC.

SOURCE BioMarin Pharmaceutical Inc.