ViroPharma Incorporated (Nasdaq: VPHM) today announced that the European Commission has granted orphan drug designation for maribavir for treatment of cytomegaloviral (CMV) disease in patients with impaired cell mediated immunity. The "Orphan Medicinal Product Designation" is designed to encourage the development of drugs which may provide significant benefit to patients suffering from rare diseases identified as "life-threatening or chronically debilitating" conditions. ViroPharma has previously received orphan drug designation for maribavir in the United States for treatment of clinically significant cytomegalovirus viremia and disease in at-risk patients.
Under EMA guidelines, Orphan Medicinal Product Designation provides 10 years of potential market exclusivity if the product candidate is approved for marketing in the European Union and the orphan designation is maintained. Orphan status also permits EMA assistance in optimizing the candidate's clinical development through participation in designing the clinical protocol and preparing the marketing application. Additionally, a drug candidate designated by the EMA as an Orphan Medicinal Product may qualify for a reduction in regulatory fees as well as a European Union-funded research grant. Finally, if a Pediatric Investigation Plan is completed, an additional two years of exclusivity could be granted for a product with Orphan Medicinal Product designation.
"We are very pleased to receive orphan designation for maribavir from the European Commission," commented John Watson, ViroPharma's senior director, regulatory affairs, Europe. "This designation recognizes the potential of maribavir to address great unmet medical needs. We commend the European Commission for providing incentives such as this for the development of drugs for rare and life threatening diseases."
ViroPharma is currently conducting two Phase 2 dose ranging studies of oral maribavir at one of three doses (400mg, 800mg or 1200mg BID) in transplant recipients. The first is a randomized, active (valganciclovir) controlled maribavir dose blinded multicenter Phase 2 study in up to 160 European hematopoietic stem cell or solid organ transplant recipients who have demonstrated CMV viremia but do not have CMV organ disease. ViroPharma is also conducting a randomized, dose blinded multicenter Phase 2 study intended to enroll up to 120 hematopoietic stem cell or solid organ transplant recipients who have resistant or refractory CMV viremia with or without CMV organ disease. This study is currently being conducted in the US with plans to extend to include European sites.