Data Equity in Action: Largest Real-World MS Analysis Confirms Fumarate Efficacy Across Racial Groups

As the multiple sclerosis (MS) research landscape begins to reckon with decades of underrepresentation, a new real-world study offers long-overdue clarity on not only efficacy but also enduring disparities.

Black and Hispanic individuals with multiple sclerosis (PwMS) face disproportionately higher disease burden, but they have long been underrepresented in clinical research. In a landmark real-world analysis using the Komodo Health claims database, researchers evaluated over 6,800 PwMS—including 2,150 Black, Hispanic, and Asian patients—treated with dimethyl or diroximel fumarate. This represents the largest dataset to date examining differential outcomes of a single disease-modifying therapy (DMT) class across diverse populations.

The researchers found that fumarates reduced the annualized relapse rate (ARR) significantly across all groups—from 0.338 to 0.252 in Black PwMS, and similarly across Hispanic, Asian, and white patients. At two years, the proportion of relapse-free patients was comparable: 77.0% in Black PwMS, 75.4% in Hispanic, and 80.5% in white populations. Importantly, despite having higher baseline severity scores and comorbidity burdens, Black patients achieved similar relapse control without elevated health care resource utilization or costs.

The absolute lymphocyte count (ALC) decline—a surrogate for immunomodulatory effect—was notably smaller in Black PwMS (10.3%) compared to Hispanic (20.1%) and white (20.4%) patients at 12 months, a finding that mirrored prior trial data. While the clinical implications of this differential lymphocyte trajectory remain uncertain, the absence of increased relapse rates supports fumarates’ immunologic selectivity across ethnicities.

Structural Disparities Still Shape Outcomes

Despite treatment parity, the study reaffirms the outsized burden carried by Black PwMS: higher baseline severity, greater comorbidity (including pulmonary and cardiac conditions), and lower commercial insurance rates. These patterns underscore the role of social determinants of health (SDOH)—including poverty, access, and systemic bias—in MS outcomes, and spotlight the urgency for more inclusive, stratified care models.

This analysis offers critical evidence that fumarates maintain efficacy across racially and ethnically diverse MS populations—even among those starting with more severe disease. It also reinforces the need for real-world, SDOH-informed datasets to shape equitable treatment strategies. With disparities in access and burden still evident, equal efficacy is necessary but not sufficient for equal outcomes.

Reference

Woodson S, Gettings EJ, Guo C-Y, et al. Real-world treatment outcomes in Black, Hispanic, Asian, and White people with multiple sclerosis treated with fumarates in the USA. Neurol Ther. 2025;14(8):1641-1656. doi:10.1007/s40120-025-00773-3