Efficacy of fumarates similar in underrepresented groups, white patients with MS

Key takeaways:

• Researchers analyzed more than 5,800 individuals with MS treated with fumarates for change in annual relapse rate at 12 months.
• At 12 months, ARR was reduced for Black, Hispanic, Asian and white patients.

DENVER — Efficacy of fumarates to treat multiple sclerosis was consistent across four racial and ethnic groups, particularly for Black, Hispanic and Asian persons, according to a poster at the American Academy of Neurology annual meeting.

“Even though minority populations present with higher disease burden and higher relapse rates, fumarates are effective [disease modifying therapies] and can be initiated in all populations of people with multiple sclerosis,” Sophia Woodson, CNP, family nurse practitioner at University Hospitals in Cleveland, told Healio in an email.

Dimethyl fumarate (DMF) and diroximel fumarate (DRF) are disease-modifying therapies for relapsing MS. As the body of knowledge surrounding the efficacy of these treatments in underrepresented groups is limited, Woodson and colleagues sought to assess their effectiveness in Black, Hispanic, Asian and white persons with multiple sclerosis (pwMS).

Their retrospective analysis culled data from the Komodo Health Claims Database to include 4,650 white, 1,241 Black, 777 Hispanic and 132 Asian adults aged 18 to 64 years with at least one claim for MS diagnosis from January 2016 to August 2022 and a claim for DMF or DRF between January 2017 and May 2022. Index date was the first claim date for fumarate prescription, and all individuals were tracked from index to first occurrence of either the end of a study, end of insurance eligibility, a gap of greater than 45 days, or switch of disease modifying therapy.

The primary outcome was change in annualized relapse rate (ARR) from 12 months pre-index to post-index, with the main secondary outcome being time to first relapse post index date up to 24 months.

Outcomes were subsequently organized by race or ethnic subgroup based on patient self-report, with all participants categorized into one subgroup only.

Baseline mean MS severity scores were: Black, 7.1 (4.2); Hispanic, 6.4 (4); Asian, 6 (3.3); and white, 6.4 (4.1). Baseline (1 year pre-index) ARR (95% CI) was 0.338 (0.297-0.385) in Black patients, compared with 0.311 (0.258-0.376), 0.295 (0.212-0.412) and 0.299 (0.273-0.326) in Hispanic, Asian and white patients, respectively.

Mean fumarate exposure post-index ranged from 449 to 559 days (Black, 449; Hispanic 488; white, 554; Asian 559).

Post-index, ARR (95% CI) was 0.252 (0.212-0.3) in Black patients, compared with 0.185 (0.138-0.248), 0.163 (0.104-0.256) and 0.214 (0.182-0.251) in Hispanic, Asian and white patients, respectively.

Estimated relapse-free proportion of patients (95% CI) at 24 months were: Black, 77% (73.7%-80.3%); Hispanic, 75.4% (71%-80%), Asian, 81.7% (73%-90.3%); white, 80.5% (70%-82.1%).

“The study demonstrates efficacy of fumarates across all racial and ethnic populations in people with multiple sclerosis,” Woodson told Healio. “Even with Black patients who are historically known to have higher disease burden, fumarates are shown to be an effective disease-modifying therapy.”