Diroximel Fumarate for Relapsing MS: How Does It Affect Clinical Outcomes?

Diroximel fumarate is an effective treatment for young adults with multiple sclerosis, according to study results presented at the 2022 Annual Meeting of the Consortium of Multiple Sclerosis Centers (CMSC) held from June 1-4, in National Harbor, Maryland.

Compared with dimethyl fumarate, diroximel fumarate has superior gastrointestinal (GI) tolerability and decreased rates of discontinuation associated with GI adverse events (AE), the researchers said. Yet, outcomes for young adult patients treated with diroximel fumarate have not previously been reported. In this study, researchers assessed diroximel fumarate outcomes among adults aged 18 to 25 years who participated in the open-label EVOLVE-MS-1 study (ClinicalTrials.gov identifier: NCT02634307).

Patients in the EVOLVE-MS-1 study had either been newly diagnosed with MS or had completed the randomized, double-blind, 5-week phase 3 EVOLVE-MS-2 study (ClinicalTrials.gov identifier: NCT03093324) of diroximel fumarate or dimethyl fumarate.

In September 2020, the EVOLVE-MS-1 study included 65 young adult patients (aged 22.6±2.0 years; 61.5% women) who had been diagnosed 1.6±2.0 years before baseline. Their Expanded Disability Status Scale (EDSS) scores were 1.66±1.10.

AEs occurred in 90.8% patients during treatment. The most frequent AEs were flushing (32.3%), nasopharyngitis (24.6%), and MS relapse (23.1%). Ten patients experienced serious AEs. The investigator deemed the 1 reported death was unrelated to treatment.

GI AEs occurred in 40% of patients, but none of these patients discontinued treatment.

Absolute lymphocyte count decreased 18% from baseline to week 48 (baseline 1.86×109/L n=65 week 48 1.52×109/L [n=56]). Annualized relapse rate (ARR) decreased 78.6% (95% CI, 61.6%-88.0%; P <.0001) from 12 months before study entry (ARR, 0.961; 95% CI, 0.79-1.17) to 2 years from baseline (ARR, 0.206; 95% CI, 0.11-0.38).

At week 48, an estimated 79% of patients were relapse free and more than half (54.7%) had no evidence of disease activity.

The researchers found that 73.2% of patients were free of gadolinium-enhancing lesions at week 48, down from 46.2% at the beginning of the study.

“Safety, GI tolerability, and efficacy in the young adult population of EVOLVE-MS-1 were consistent with those in the overall adult study population,” the researchers said. “Clinical and radiologic (gadolinium-enhancing lesion counts) outcomes significantly improved, and no discontinuations due to GI AEs were seen. These data suggest that [diroximel fumarate] is an effective treatment option for young adults with MS.”

The researchers said they will also assess data for patients aged 18 to 29 years.

Disclosure: This research was supported by Biogen. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.


Wray S, Zhu C, Singer BA. Diroximel fumarate in young adults with relapsing-remitting multiple sclerosis: interim safety and efficacy results from the Phase 3 EVOLVE-MS-1 study. Presented at: CMSC 2022 Annual Meeting; June 1-4, 2022; National Harbor, Maryland. Abstract DMT57.