Dimethyl fumarate is associated with lower rates of infection and lower infection-related healthcare costs when compared with ocrelizumab

• Published in: Multiple sclerosis and related disorders 2022-07, Vol.63, p.103921-103921, Article 103921
• Main Authors: Nicholas, Jacqueline A, Gudesblatt, Mark, Garabedian, Meghan, Belviso, Nicholas, Shen, Changyu, Geremakis, Caroline, Shankar, Sai L, Mendoza, Jason P, Lewin, James B
• Format: Article
• Language: English
• Subjects: Dimethyl fumarate; Healthcare resource costs; Healthcare resource utilization; Infection; Multiple sclerosis; Ocrelizumab
• ISSN: 2211-0348; 2211-0356
• DOI: 10.1016/j.msard.2022.103921

•DMF-treated patients had a lower infection risk than matched OCR-treated patients.•Infection-related healthcare costs were lower for DMF- vs OCR-treated patients.•Inpatient infections accounted for most of the healthcare cost difference. Infections in people with multiple sclerosis (PwMS) may have a detrimental effect on disease progression, risk of hospitalization, and healthcare resource utilization (HRU). The infection risk and HRU costs may vary between disease-modifying therapies (DMTs); however, the individual risks and differences associated with DMTs are not well characterized. Some DMTs may increase the risk for infections in PwMS; however, previous studies have reported an intact humoral immune response in dimethyl fumarate (DMF)-treated patients. The objective was to compare infection-related HRU and healthcare costs (HCCs) between PwMS treated with DMF or ocrelizumab (OCR). Eligible patients were identified from the Optum US claims database between April 2017 and September 2020 (DMF n = 1429; OCR n = 3170). Patients were followed from index date to first occurrence of: (1) end of study, (2) end of insurance eligibility, (3) discontinuation of index DMT, or (4) switch from index DMT to another DMT. Outcomes were annualized rate of infection encounters (defined as infection encounters [n] during follow-up window / days followed [n] × 365); annualized infection-related HCCs (defined as aggregated costs of infection encounters during follow-up window / days followed [n] × 365); location-specific infections, and overall infection-related events. Propensity score matching (PSM) 1:1 method was used; PS was calculated via logistic regression for probability of DMF treatment conditional on demographics and comorbidities. Mean differences (MD) were reported for infection encounter measures. After PSM, DMF and OCR cohorts (n = 1094 in each cohort) were balanced based on baseline characteristics (standardized MD of adjusted baseline characteristics