A treatment response score consisting of a combination of age, sex, relapses in the previous year, disease duration, and Expanded Disability Status Scale (EDSS) could help determine which patients with multiple sclerosis (MS) would benefit from glatiramer acetate or interferon beta-1 (IFN-ß1a), according to study results published in Neurology.
Study researchers sought to compare the effectiveness of intramuscular IFN-ß1a and glatiramer acetate MS immunotherapies by identifying patient profiles associated with treatment efficacy.
To achieve this, they utilized data from 2 independent MS datasets, including the randomized CombiRx trial (ClinicalTrials.gov Identifier: NCT00211887) and an observational cohort from the MSbase registry. These data were used to produce and validate a treatment response score. The primary outcome of the study was the annualized relapse rate (ARR) of glatiramer acetate compared with IFN-ß1a through 3 years.
The treatment response score used in this study was calculated using the CombiRx dataset as the linear combination of baseline variables chosen from the CombiRX and MSBase cohorts. These variables included age, sex, amount of relapses in the year prior to the start of treatment, disease duration, and EDSS. The treatment response score was then applied to the MSBase for validation.
Data were available for 503 patients of the IFN-ß1a and glatiramer acetate arms. Treatment with glatiramer acetate was associated with a greater reduction in the ARR compared with IFN-ß1a by approximately 28% (ARR ratio, 0.72; 95% CI, 0.55-0.95; P =.018).
Patients who experienced the most benefit from glatiramer acetate compared with IFN-ß1a had an ARR ratio of 0.40 (95% CI, 0.25-0.63). Among patients with the highest treatment response score, those treated with IFN-ß1a had a 14% lower ARR compared with those treated with glatiramer acetate (ARR ratio, 1.14; 95% CI, 0.59-2.18; P =.012). Additionally, among patients with an intermediate treatment response score, the ARR was 10% lower for those treated with glatiramer acetate than those who received IFN-ß1a (ARR ratio, 0.90; 95% CI, 0.61-1.34).
The study researchers noted that the treatment score cannot be generalizable to all IFN formations because the score was developed and validated for only intramuscular IFN-ß1a 30 μg.
Despite this limitation, they concluded that their “methodology…can be applied to all the comparisons involving currently available therapies” and “should be a stimulus for pharmaceutical companies to allow the re-analysis of their clinical trial data to try to define the drug responders’ profiles.”
The study’s treatment response score calculator can be found here: https://osf.io/wyk5h/?view_only=ccdf366d44fa4b9b9da585a0e1c4f79b
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Bovis F, Kalincik T, Lublin F, et al. Treatment response score to glatiramer acetate or interferon beta-1a. Published online October 6, 2020. Neurology. doi:10.1212/WNL.0000000000010991