Real world drug utilization patterns in the first years following a relapsing-remitting multiple sclerosis diagnosis

Real-world drug utilization studies provide valuable insights into the treatment of relapsing-remitting multiple sclerosis (RRMS). As treatment dynamics in the Dutch context are limited, we studied drug utilization patterns in the first two years following a RRMS diagnosis in the Netherlands.

People diagnosed with RRMS between 2016 and 2022 were included from the Dutch Multiple Sclerosis Registry, a registry-based observational study. Disease modifying therapies (DMTs) were categorized as low-, moderate- or high-efficacy. Initiation, discontinuation, reasons for discontinuation, and switches in the first two years post-diagnosis were evaluated. We calculated proportions with 95% confidence intervals (CI).

We included 806 PwMS. 2-year discontinuation was highest for low- (51%, CI: 45-57) and moderate-efficacy (37%, CI: 32-42) DMTs, mainly due to adverse events or insufficient efficacy. Of those switching from these therapies, 26% (CI: 21-33) switched to low-efficacy and 37% (CI: 30-44) to moderate-efficacy therapies, of which 32% (CI: 34-41) discontinued their second DMT. Anti-CD20 therapies were discontinued in 5% (CI: 2-15) of initiations. High-efficacy DMT use rose from 12% (CI: 10-15) at initiation to 29% (CI: 26-33) at year two.

Our results indicate high risks of discontinuation of low- and moderate-efficacy DMTs, in contrast to low risk of discontinuation of anti-CD20 therapies. These findings may give further direction to research on finding the optimal treatment strategy and may inform health care providers in the Netherlands.