Investigators noted the need for more transformational treatments to improve disability for patients with both primary and secondary progressive multiple sclerosis.
Analyses of pooled placebo arm data from clinical trials in multiple sclerosis (MS) suggest that the percentage of patients with disability progression and improvement within the first year were similar between those with primary progressive multiple sclerosis (PPMS) and secondary progressive multiple sclerosis (SPMS). These findings were also observed after stratifying for baseline disability severity.
Findings were presented at the Americas Committee for Treatment and Research in Multiple Sclerosis (ACTRIMS) Forum 2022, February 24-26, in West Palm Beach, Florida, and further support similarities between the 2 progressive MS patient populations. Investigators, including Natalia Sadetsky, MD, PhD, MPH, senior director, Health Economics & Outcomes Research, Atara Biotherapeutics, posited the need for more transformational treatments to improve disability, due to observed high disability progression, between 9.2% and 11.1%, and limited disability improvement, between 5.6% and 6.5% at 6 months, confirmed at 12 months in patients with PPMS and SPMS receiving placebo.
Placebo arm data were included from 9 clinical trials, with a total of 251 patients with PPMS (mean age, 48.9 years) and 449 patients with SPMS (mean age, 48.5 years) enrolled. For those with PPMS, 46.2% had a baseline Expanded Disability Status Score (EDSS) of 5.5 or greater, compared with those with SPMS, where 62.1% had a baseline EDSS score of 5.5 or greater. Investigators observed no difference between patients with PPMS and SPMS in disability improvement at 6 months confirmed at 12 months, at rates of 5.6% vs 6.5%, respectively (P = .64). Further, there was no difference between patients with PPMS and SPMS in disability improvement at 12 months confirmed at 18 months, at rates of 8.8% vs 7.6%, respectively (P = .20).
When investigating disability progression, Sadetsky et al did not observe a difference between PPMS and SPMS groups at 6 months confirmed at 12 months, at rates of 9.2% vs 11.1%, respectively (P = .41), or at 12 months confirmed at 18 months, at rates of 8.8% vs 7.6%, respectively (P = .58). Additionally, disease severity at baseline did not modify the result for overall disability improvement (EDSS ≤5.0: 7.4% vs 6.5% [P = 0.75]; EDSS ≥5.5: 6.0% vs 10.8% [P = 0.14]; pinteraction=0.22), or overall disability progression (EDSS ≤5.0: 14.1% vs 15.3% [P = 0.77]; EDSS ≥5.5: 22.4% vs 20.8% [P = 0.72]; pinteraction=0.65).
To be included in the study, patients were required to have a diagnosis of PPMS or SPMS, be between the ages of 18 and 61 years, and have a baseline EDSS score between 3 and 6.5 with at least 2 consecutive follow-up EDSS scores in the Multiple Sclerosis Outcomes Assessment Consortium Placebo Database. Confirmed disability progression or improvement was defined as an increase or decrease of 1.0 or more from EDSS baseline score between 5.0 and 0.5 from an EDSS baseline score of 5.5 or greater, which was confirmed at the 6-month timepoint. Outcomes between the 2 patient groups were compared, with events assessed at 6 months confirmed at 12 months and at 12 months confirmed at 18 months.
For more coverage of ACTRIMS Forum 2022, click here.