Effects of delayed-release dimethyl fumarate (DMF) on health-related quality of life in patients with relapsing-remitting multiple sclerosis: an integrated analysis of the phase 3 DEFINE and CONFIRM studies.

Purpose: Delayed-release dimethyl fumarate (DMF; also known as gastro-resistant DMF) has been reported to have clinical and neuroradiologic efficacy in people with relapsing-remitting multiple sclerosis (RRMS) in the Phase 3 DEFINE and CONFIRM studies. An integrated analysis of data from DEFINE and CONFIRM was conducted to estimate more precisely the therapeutic effects of delayed-release DMF. Here we describe the impact of RRMS on health-related quality of life (HRQoL) at baseline and assess the effects of delayed-release DMF on prespecified HRQoL end points over 2 years.

Methods: Patients with RRMS were randomly assigned to receive delayed-release DMF 240 mg PO BID or TID or matching placebo for up to 2 years (96 weeks). As a tertiary end point in both studies, patient-reported HRQoL was assessed using the Physical and Mental Component Summaries (PCS and MCS, respectively) of the 36-item Short Form Health Survey (SF-36); global assessment of well-being, as measured on a visual analog scale (VAS); and the EuroQoL-5D (EQ-5D) VAS, administered at baseline and at weeks 24, 48, and 96. Higher scores suggested better HRQoL.

Findings: The integrated analysis included 2301 patients treated with delayed-release DMF BID (n = 769) or TID (n = 761) or placebo (n = 771). The mean PCS and MCS scores at baseline were lower overall compared with those reported in the general US population and were ≥5 points lower (a clinically meaningful difference) in patients with a baseline Expanded Disability Status Scale (EDSS) score of ≥2.5 compared with those in patients with a baseline EDSS score of 0. At 2 years, mean PCS and MCS scores were increased from baseline in the patients treated with delayed-release DMF, whereas the mean PCS and MCS scores were decreased from baseline in the placebo group; the difference in PCS and MCS scores was significant for the delayed-release DMF BID and TID groups compared with placebo. SF-36 subscale scores generally remained stable or were improved relative to baseline in patients treated with delayed-release DMF and decreased in patients receiving placebo; improvements were significant for delayed-release DMF BID and TID versus placebo on most subscales. Compared with that in the placebo group, the proportions of patients in the delayed-release DMF groups exhibiting a ≥5-point improvement in SF-36 score were significantly higher. The following factors were found to be predictive of improved PCS and MCS scores at 2 years: delayed-release DMF treatment, lower baseline EDSS score, age ≤40 years (PCS only), and corresponding lower baseline PCS or MCS score. Changes from baseline in VAS and EuroQoL-5D scores were generally consistent with changes in SF-36 scores.

Implications: These HRQoL benefits parallel the improvements in clinical and magnetic resonance imaging end points with delayed-release DMF, suggesting that delayed-release DMF treatment improves patient-perceived health status as well as neurologic and physical functioning. ClinicalTrials.gov identifiers: NCT0042012; NCT00451451.