The Efficacy of Peginterferon Beta-1a in Early and Later-Stage Patients With Multiple Sclerosis: A 1-Year Subgroup Analysis Based on Disease Duration from the ADVANCE Study (P7.267)

OBJECTIVE: To investigate the efficacy of subcutaneous peginterferon beta-1a (PEG-IFN) in patients with early and later-stage symptoms of relapsing remitting multiple sclerosis (RRMS). BACKGROUND: In the Phase 3 ADVANCE study in patients with RRMS, PEG-IFN dosed at 125 μg every 2 weeks was more effective than placebo and had a safety profile similar to other beta interferons. This subgroup-analysis evaluated the efficacy of PEG-IFN versus placebo in patients with early (<3 years) and later-stage (蠅3 years) symptom onset. DESIGN/METHODS: ADVANCE was a two-year, double-blind, placebo-controlled, Phase 3 study in patients aged 18-65 years with RRMS. This subgroup-analysis evaluated the efficacy of PEG-IFN versus placebo at Year 1 in those RRMS patients with early (<3 years patients) and with later-stage (蠅3 years patients) symptom onset. Efficacy endpoints evaluated were annualized relapse rate (ARR) and 24-week confirmed disability progression (CDP24W). RESULTS: The study population comprised 512 patients (n=157 for p =0.009) reduction in adjusted ARR in p =0.016) reduction in adjusted ARR in >3 year patients receiving PEG-IFN (0.289, 95[percnt] CI 0.229-0.366) versus placebo (0.413, 95[percnt] CI 0.334-0.511). A Cox proportional hazard model showed that PEG-IFN reduced the risk of CDP24W versus placebo by 29[percnt] in p =0.55), and by 60[percnt] in 蠅3 year patients ( p =0.005). CONCLUSIONS: PEG-IFN, as with other treatments for MS, is more efficacious in reducing relapse rate versus placebo in earlier MS (50.2[percnt]) than later. However, PEG-IFN is also highly efficacious in reducing CDP24W (60[percnt]) in longer-term RMS patients. Study sponsored by: Biogen Idec Inc. (Cambridge, MA, USA). Disclosure: Dr. Kieseier has received personal compensation for activities with Biogen Idec, Genzyme, Novartis, and Teva Neuroscience. Dr. Newsome has received personal compensation for activities with Biogen Idec, Novartis, and Genzyme as scientific advisory board participant. Dr. Newsome9s employer has received research support from Biogen Idec and Novartis. Dr. Shang has nothing to disclose. Dr. Liu has received personal compensation for activities with Biogen Idec as an employee. Dr. Hung has received personal compensation for activities with Biogen Idec as an employee. Dr. Sperling has received personal compensation for activities with Biogen Idec as an employee.