Rebif® Quality of Life (RebiQoL): A randomized, multicenter, Phase IIIb study evaluating quality-of-life measures in patients receiving the serum-free formulation of subcutaneous interferon beta-1a for the treatment of relapsing forms of multiple sclerosi

BackgroundIn clinical studies, treatment with subcutaneous interferon beta-1a (IFNβ-1a) has been shown to reduce relapse rates and slow the progression of physical disability in patients with relapsing forms of multiple sclerosis (MS). A formulation of subcutaneous IFNβ-1a has been developed that is free of fetal bovine serum and human serum albumin.ObjectiveTo evaluate (a) the impact on quality of life (QoL) and treatment satisfaction of transitioning from the original formulation of subcutaneous IFNβ-1a to the serum-free formulation in patients with relapsing forms of MS; and (b) the impact of dose titration versus non-titration during the transition on tolerability and patterns of analgesic use. QoL was measured by the Multiple Sclerosis Treatment Concerns Questionnaire Global Side Effects (GSE) score.MethodsPatients who had received the original formulation of IFNβ-1a subcutaneously for ≥24 weeks were randomized to receive the serum-free formulation of IFNβ-1a 44 μg subcutaneously three times weekly for 12 weeks, with or without a dose titration over a 4-week period. After week 12, patients continued to receive serum-free subcutaneous IFNβ-1a during a safety extension phase until they completed between 84 and 112 weeks of treatment. The primary endpoint was the percentage change from baseline to week 12 in GSE score in all patients.ResultsA total of 232 patients were randomized (titrated n=113; non-titrated n=119). The mean percent change (improvement) from baseline to week 12 in the GSE score was 5.0% (p<0.001 for mean change in GSE score from baseline); this change was similar between titrated and non-titrated patients and met criteria for non-inferiority to the original formulation. Adverse event (AE) incidence and use of analgesics for the treatment of flu-like symptoms (FLS) were less common in the titrated group. Few patients (<2%) discontinued due to AEs during weeks 0 to 12.ConclusionPatients with relapsing forms of MS who transitioned from original-formulation subcutaneous IFNβ-1a to serum-free subcutaneous IFNβ-1a had overall improved QoL scores at 12 weeks of treatment. Titration during the transition resulted in a lower requirement for analgesic treatment of FLS and fewer AEs.

► Patients with relapsing MS were transitioned to serum-free subcutaneous IFNβ-1a.
► Patients were randomized to treatment either with or without a dose titration.
► Patients had overall improved quality of life scores at 12 weeks.
► Incidence of adverse events was lower in the titrated group.
► Titration reduced the requirement for analgesic treatment of flu-like symptoms.