Inflammatory activity a modifiable component in primary progressive multiple sclerosis: JAMA

A study was conducted to investigate the effectiveness of DMTs on the risk of becoming wheelchair dependent in a real-world population of patients with primary progressive multiple sclerosis.

This was a multicenter, observational, retrospective, comparative effectiveness research study. Data were extracted on November 28, 2018, from the Italian multiple sclerosis register and analyzed from June to December 2021. The mean study follow-up was 11 years. Included in the study cohort were patients with a diagnosis of primary progressive multiple sclerosis and at least 3 years of Expanded Disability Status Scale (EDSS) evaluations and 3 years of follow-up.

The results of the study are:

• From a total of 3298 patients with primary progressive multiple sclerosis, 2633 were excluded because they did not meet entry criteria for the phase 3, multicenter, randomized, parallel-group, double-blind, placebo-controlled study to evaluate the efficacy and safety of ocrelizumab in adults with PPMS (ORATORIO) trial. Among the remaining 665 patients, 409 were further selected for propensity score matching
• In the matched cohort, during the study follow-up, 37% of patients (152 of 409) reached an EDSS score of 7.0 after a mean (SD) follow-up of 10.6 (5.6) years.
• A higher EDSS score at baseline was associated with a higher risk of an EDSS score of 7.0, whereas the interaction term between DMT and superimposed relapses was associated with a reduced risk of an EDSS score of 7.0
• Similar findings were obtained when treatment according to DMT class was considered and when DMT was included as a time-dependent covariate.
• These results were confirmed in the subgroup of patients with available magnetic resonance imaging data.

Thus, the results of this comparative effectiveness research study suggest that inflammation also occurs in patients with PPMS, may contribute to long-term disability, and may be associated with a reduced risk of becoming wheelchair dependent by current licensed DMTs.

Reference:

Portaccio E, Fonderico M, Iaffaldano P, et al. Disease-Modifying Treatments and Time to Loss of Ambulatory Function in Patients With Primary Progressive Multiple Sclerosis. JAMA Neurol. Published online July 25, 2022. doi:10.1001/jamaneurol.2022.1929

Keywords:

Portaccio E, Fonderico M, Iaffaldano P, Disease-Modifying, Treatments, Time, Loss, Ambulatory Function, Patients, Primary, Progressive, Multiple, Sclerosis, JAMA Neurology