1Jacqueline Nicholas, 2Nick Belviso, 2Geentanjoli Banerjee, 2Caroline Geremakis, 2Robin Avila, 2Karthik Bodhinathan

1OhioHealth MS Center, Riverside Methodist Hospital, Columbus, United States; 2Biogen, Cambridge, United States

Background:

Natalizumab (NTZ) and ocrelizumab (OCR) are high-efficacy disease-modifying therapies (DMTs) approved to treat relapsing forms of multiple sclerosis (MS). Real-world head-to-head data comparing relapses and related hospitalization rates for high-efficacy DMTs, including NTZ vs OCR, are limited. To compare claims-based relapses and relapse-related hospitalization rates for MS patients treated with NTZ or OCR using data from a large insurance claims database.

Material(s) and Method(s):

This retrospective analysis of the Optum claims database included patients with a diagnosis of MS (≥1 inpatient or ≥2 outpatient claims of International Classification of Diseases [ICD]-9 340 or ICD-10 G35 between 1 April 2017 and 30 September 2020), were naive to study DMTs in the year prior to the initial prescription (index date), and were treated with NTZ or OCR during the study period. Relapses included outpatient events with an MS diagnosis code followed by steroid use within 7 days and hospitalization events with MS as the primary diagnosis code. Inverse probability weighting (IPW) was used to adjust for differences between groups in 17 baseline covariates, including age, number of MS symptoms, prior DMT use, comorbidities, and baseline (index) costs.

Result(s):

The analysis included 835 NTZ and 3497 OCR patients. After IPW, NTZ (n=4342) and OCR (n=4333) patients were well balanced with all standardized differences ≤0.1. Mean follow-up time was approximately 0.9 and 1.0 years for NTZ and OCR patients, respectively. NTZ patients had longer time to first relapse vs OCR with hazard ratio (HR) significantly favoring NTZ (0.70 [95% confidence interval (CI): 0.55–0.88]; P<0.01). The HR for time to first MS-related emergency room (ER) visit did not differ significantly between groups. Mean annualized rates were significantly lower with NTZ than with OCR for any relapse (0.30 vs 0.43; mean difference: –0.13 [95% CI: –0.25, –0.02]; P=0.02) and outpatient relapse (0.22 vs 0.36; mean difference: –0.14 [95% CI: –0.24, –0.04]; P=0.01); but did not differ for MS-related ER visits (0.09 vs 0.08; P=0.82) and relapse-related hospitalizations (0.07 vs 0.07; P=0.83).

Conclusion(s):

Rates of relapses overall were significantly lower with NTZ than with OCR. Though relapses were insurance claims-based and not physician reported, these results provide a direct comparison of relapse-related outcomes and healthcare utilization in MS patients treated with NTZ or OCR in real-world settings.