New study uncovers therapeutic inertia in the treatment of women with multiple sclerosis

A new study has revealed significant therapeutic inertia in the treatment of women with multiple sclerosis (MS), highlighting gender disparities that could impact long-term health outcomes for women of childbearing age. 

The findings, presented at the ECTRIMS (European Committee for Treatment and Research in Multiple Sclerosis) 2024 Congress, suggest that concerns related to pregnancy may lead to delayed or reduced use of disease-modifying treatments (DMTs), even before pregnancy becomes a consideration.

In an extensive analysis of 22,657 patients with relapsing MS (74.2 per cent women) who were on the French MS registry (OFSEP), researchers found that over a median follow-up of 11.6 years, women had a significantly lower probability of being treated with any DMT (OR=0.92 [95% CI 0.87-0.97]) and were even less likely to be prescribed high-efficacy DMTs (HEDMTs) (OR=0.80 [95% CI 0.74-0.86]).

The difference in DMT usage varied across different treatments and over time. Teriflunomide, fingolimod, and anti-CD20 therapies were significantly underused throughout their entire availability, (OR 0.87 [95% CI 0.77-0.98], OR 0.78 [95% CI 0.70-0.86], and OR 0.80 [95% CI 0.72-0.80, respectively]. Interferon and natalizumab were initially used less frequently, but their usage equalised over time (OR 0.99 [95% CI 0.92-1.06], OR 0.96 [95% CI 0.86-1.06], respectively). In contrast, glatiramer acetate and dimethyl fumarate were initially used equally between genders, but eventually became more commonly prescribed to women (ORs 1.27 [95% CI 1.13-1.43], OR 1.17 [95% CI 1.03-1.42], respectively).

The study further highlighted that the disparity in treatment emerged after two years of disease duration for DMTs and as early as one year for HEDMTs. Interestingly, this gender-based treatment gap did not significantly vary with patient age, indicating that therapeutic inertia may persist regardless of the woman’s stage in life.

“These findings underscore the critical need to reassess how we make treatment decisions for women with MS, particularly those of childbearing age,” said Prof Sandra Vukusic, lead author of the study. “Women may not be receiving the most effective therapies at the optimal time, often due to concerns about pregnancy risks that may never materialise. The use of DMTs and HEDMTs is frequently limited by potential and unknown risks associated with pregnancy, as there is often insufficient data available when these drugs first come to market.”

Both neurologists and patients contribute to this therapeutic inertia, many taking a precautionary approach and avoiding these treatments, she said.

“The main impact of this inertia is the less effective control of disease activity during DMT-free periods, leading to the accumulation of lesions and an increased risk of long-term disability,” stressed Prof Vukusic. “This represents a real loss of opportunity for women, especially in an era where DMTs are so effective when used early.”

To address these challenges, the study recommends a multifaceted approach: “Empowering patients through education, improving the dissemination of recent findings, providing formal training for specialists, and actively collecting and analysing real-world data are essential steps to reducing therapeutic inertia and ensuring equity in treatment,” Prof Vukusic concluded.

The 40th ECTRIMS Congress took place between 18-20 September 2024 in Copenhagen, Denmark. For more information go to https://ectrims.eu/.