SAN DIEGO, May 2, 2013 (GLOBE NEWSWIRE) -- Zogenix, Inc. (Nasdaq:ZGNX), a pharmaceutical company commercializing and developing products for the treatment of central nervous system disorders and pain, today announced positive top-line results from its extended Phase 1 clinical trial of Relday™, an investigational candidate of a proprietary, once-monthly subcutaneous formulation of risperidone for the treatment of schizophrenia. If approved, Relday has the potential to be the first subcutaneous antipsychotic product that allows for once-monthly dosing. Efforts are now underway to secure a strategic development and commercialization partner for Relday. The extended Phase 1 clinical trial included a 100 mg dose of Relday, following previously reported positive results with 25 and 50 mg doses. The results for the 100 mg dose showed that risperidone blood concentrations in the therapeutic range were achieved on the first day of dosing, and maintained throughout the one-month period. In addition, dose proportionality has now been established across the full dose range that would be anticipated to be used in clinical practice (50 to 100 mg). The 100 mg dose was safe and well-tolerated, with no unexpected adverse events, including injection site reactions, as compared to the initial Phase 1 clinical trial with the 25 and 50 mg doses. The adverse events were generally mild to moderate and consistent with other risperidone products. "With the positive top-line results from the Relday Phase 1 extension, we believe that we have now confirmed the product candidate's viability across the anticipated commercial dosing range," said Stephen Farr, Ph.D., president of Zogenix. "We are well positioned to begin a multi-dose clinical trial to provide steady-state pharmacokinetic and safety data, once a partner is secured, prior to initiating Phase 3 development studies." Roger L. Hawley, chief executive officer of Zogenix, said, "We now have sufficient data to formalize our business development discussions, with a goal of securing a strategic development and commercialization partner. While we plan to retain U.S. rights to Relday, based on the 505(b)(2) NDA regulatory pathway and previous discussions, we believe there is strong partnering interest in Relday."