BioMarin Pharmaceutical Inc has filed an investigational new drug application (IND) with the US FDA for Phenoptin, BioMarin's proprietary oral formulation of 6R-BH4, for the treatment of phenylketonuria (PKU). The company expects to initiate a clinical study of Phenoptin based on this IND by the end of 2004.

On July 20, 2004, BioMarin announced positive results from an investigator-sponsored pilot clinical study of oral 6R-BH4 in PKU patients. Consistent with previous studies of 6R-BH4, approximately half of the patients in the study experienced a substantial reduction in blood phenylalanine levels without serious adverse effects, suggesting that Phenoptin could be a valuable therapeutic for managing PKU, the company release added.

"Our recently submitted IND contains an unusually large set of data on 6R- BH4 that we expect will advance this program toward a later stage of development and will enable us to initiate a clinical study later this year," stated Emil Kakkis, senior vice president of Business Operations at BioMarin. "We look forward to having discussions with the FDA in the coming months that will help define the specific timeline and development course for this much needed therapeutic option for people living with PKU," he added.

Louis Drapeau, acting chief executive officer of BioMarin stated, "The passion and tenacity the BioMarin team has for developing new therapeutics for serious diseases has contributed greatly to the rapid development of our PKU programme." Drapeau continued, "In addition to these important developments in our PKU program, we also remain on track to file for marketing authorization for Aryplase, potentially our third approved product, in both the United States and European Union in the fourth quarter of this year. BioMarin is moving aggressively ahead with its programmes in all areas."

BioMarin Pharmaceutical Inc develops innovative biopharmaceuticals and commercializes therapeutics for serious paediatric diseases.