Today Biogen Idec (NASDAQ: BIIB) released the primary efficacy analysis and safety data from its Phase 3 pivotal clinical trial, ADVANCE. Results support peginterferon beta-1a as a potential treatment dosed every two weeks or every four weeks for relapsing-remitting multiple sclerosis (RRMS). Peginterferon beta-1a is a new molecular entity in which interferon beta-1a is pegylated to extend its half-life and prolong its exposure in the body, enabling study of a less frequent dosing schedule. The primary endpoint of ADVANCE, annualized relapse rate (ARR) at one year, was met for both the two-week and four-week dose regimens. Results showed that peginterferon beta-1a also met the secondary endpoints of risk of 12-week confirmed disability progression, proportion of patients who relapsed and magnetic resonance imaging (MRI) assessments for both dose regimens. Adverse events (AEs), serious adverse events (SAEs) and discontinuations due to AEs were similar across both dose groups. Overall with both dose regimens studied, the risk-benefit profile of peginterferon beta-1a appears to be favorable. “If approved, peginterferon beta-1a will represent an innovation that offers patients a less frequent dosing schedule of no more than 26 doses annually, as well as a significant reduction in relapses and disability progression,” said Gilmore O’Neill, vice president, Global Neurology Late Stage Clinical Development at Biogen Idec. “Interferons are an important and widely used option for many patients. As a leader in MS, Biogen Idec has the deepest MS pipeline in the industry and we remain steadfast in our commitment to study compounds that target a broad range of patients’ needs.” The ADVANCE study included more than 1,500 patients with RRMS and was designed to evaluate the efficacy, safety and tolerability of peginterferon beta-1a compared to placebo at one year. Results showed that when administered via subcutaneous (SC) injection, peginterferon beta-1a 125 mcg demonstrated a significant reduction in ARR at one year. Compared to placebo, ARR reduction with two-week dosing was 35.6 percent (p<0.001) and with four-week dosing was 27.5 percent (p<0.02).