DMT Switching Associated With Lower Adherence, Persistence Among Patients With MS

Health-system specialty pharmacies (HSSPs) supported adherence and persistence to disease-modifying therapies (DMTs) among patients with multiple sclerosis (MS), but DMT switching was associated with poorer outcomes. Researchers published their findings in Multiple Sclerosis and Related Disorders.

Previous research suggests patient adherence and persistence are crucial for successful treatment outcomes in MS, but suboptimal adherence rates and early treatment discontinuation have been observed, researchers said. The investigators aimed to validate the outcomes of the HSSP practice model by conducting a multisite prospective cohort study.

The study included patients who had received at least 3 fills of a DMT at an HSSP between January 2020 and June 2021. Exclusions were made for pregnant patients or those who had passed away. The study consisted of a 6-month enrollment period followed by 12 months of follow-up. 

Adherence was measured using pharmacy claims, specifically the proportion of days covered (PDC), during the follow-up period. Persistence was assessed as the time from the initial DMT fill to the first instance of a gap between medication exhaust and refill exceeding 60 days. 

Adherence and persistence calculations were evaluated at the therapeutic class level, encompassing any self-administered DMT dispensed by the HSSPs. The Kaplan-Meier method and Cox proportional hazards regression were employed to analyze the data.

The study included 968 patients. Glatiramer acetate, fingolimod, and dimethyl fumarate were the most filled self-administered DMTs. Most patients (96%) did not switch DMTs during the study period. 

The median PDC was 0.97, indicating high adherence levels across all sites. Patients who switched DMTs were 76% less likely to have a higher PDC compared to those who did not switch, according to the findings. 

Overall, 86% of patients were persistent to DMT over the 12-month study period, with a median time to non-persistence of 231 days. Patients who switched medications were 2.4 times more likely to be non-persistent. The most common reasons for non-persistence were discontinuation or holding medication for an extended period, often due to decisions made by the patient or prescriber, researchers said.

The findings suggest HSSPs have a positive impact on DMT adherence and persistence in patients with MS. The high rates of adherence and persistence observed indicate the potential benefits of the HSSP practice model in improving patient outcomes. However, switching DMTs was associated with lower adherence and persistence rates, highlighting the need for enhanced care coordination or additional resources to optimize therapy transitions, researchers said.

The authors said further research and evaluation across multiple HSSPs are warranted to validate these findings and explore additional strategies to enhance DMT adherence and persistence in patients with MS.

Reference:
Zuckerman AD, DeClercq J, Simonson D, et al. Adherence and persistence to self-administered disease-modifying therapies in patients with multiple sclerosis: A multisite analysis. Mult Scler Relat Disord. Published online April 28, 2023. 2023;75:104738. doi:10.1016/j.msard.2023.104738