Impact of COVID-19 on prescribing patterns and treatment selection of disease modifying therapies in multiple sclerosis

Background: Certain classes of multiple sclerosis (MS) disease modifying therapies (DMTs) have been associated with an increased risk of severe COVID-19, resulting in prescribers considering changes in their practice habits during the COVID-19 pandemic. This study assessed for differences in prescribing patterns of DMTs along with the reason(s) for modification of therapy over time. Methods: A retrospective review of medical records at Johns Hopkins Health System was performed. The timeframe of the study, April 2019 to December 2021, was divided into three subcategories: pre-pandemic (April 2019–March 2020), pre-vaccine availability (April 2020–March 2021), and post-vaccine availability (April 2021–December 2021). Patients were identified through dispense reports from the pharmacy dispensing system, and prescribing report from the health-system electronic health record (EHR). The health-system EHR was also utilized to conduct chart reviews for a subset of patients that had a modification in their therapy during the specified timeframes. The study included adult patients that were prescribed at least one DMT through the Johns Hopkins Pharmacy Services during the study timeframe and those who stayed on their DMT for at least 2 months without tolerability issues. Descriptive statistics were used to compare the prescribing practices during the timeframes with the percentage of prescribing for each type of treatment and to assess the percentage of patients that switched therapies in the different time periods. Results: Based on prescribing report data, 670 patients were prescribed a DMT during the pre-pandemic period with infusion therapies being the most prescribed therapies during this timeframe (38%), followed by oral therapies at 35%. In comparison, a total of 620 patients were prescribed a DMT during pre-vaccine pandemic and the percentage of prescriptions of infusion therapies decreased to 28% (-10%) during this timeframe, whereas oral prescriptions increased to 42% (+7%). These trends continued during the post-vaccine timeframe where infusion therapies decreased to 26% (-12%) and oral therapies increased to 43% (+8%) in reference to the pre-pandemic period. Prescribing patterns of self-injectable therapies remained stable throughout the 3 timeframes. A dispensing report cohort of 500 patients were randomly selected for chart reviews to assess therapy modifications due to COVID-19. The percentage of therapy change due to COVID-19 increased to 45.2% during pre-vaccine period and remained at 38.4% during post-vaccine period when compared to the pre-pandemic reference period. The majority of changes due to COVID-19 were delays in infusion therapies (96% during pre-vaccine, and 94% during post-vaccine), not medication changes. Conclusion: Prescribing patterns and therapy modifications of DMTs for MS patients were impacted by COVID-19, with the greatest changes observed for the infusion therapies, including reduction in percentage of infusion prescriptions and delays in infusion therapies. Prescribing patterns of lower efficacy self-injectable therapies (interferon-beta and glatiramer acetate) remained stable. The outcomes of this study provide background for future outcomes-focused research studies in MS.