Use of disease-modifying therapies (DMTs) for the treatment of multiple sclerosis (MS) is driven by many factors that are not well understood. In March 2017, ocrelizumab (OCR), an intravenous humanized anti-CD20 monoclonal antibody (mAb), was approved in the United States for the treatment of relapsing-remitting MS (RRMS) and primary progressive MS (PPMS).
To examine whether the type of MS patient being treated with OCR first line or as a first switch is changing over time in the United States.
Cross-sectional MS patient-level data were collected once-yearly from practicing United States neurologists from 2017 to 2020. Contributed chart review data were from MS patients either initiating their first DMT (2017 n=1,033; 2018 n=1,059; 2019 n=1,006) or switching to a new DMT (2018 n=1,035; 2019 n=1,003; 2020 n=1,009) within the prior three months. Analyses focused on new OCR starts (2017 n=70; 2018 n=107; 2019 n=102) and first switches to OCR (2018 n=60; 2019 n=85; 2020 n=90). Relapsing forms of MS (RMS) is defined as clinically isolated syndrome and RRMS.
Overall use of OCR in treatment-naïve MS individuals has increased since 2017, with a decrease in PPMS offset by an increase in RMS. By 2019, OCR was the initial DMT choice in 7% of RMS individuals, while use decreased from 63% in 2017 to 35% of PPMS. Of all new OCR DMT starts evaluated in 2019, RMS made up 58% and PPMS 31%. OCR starts are increasingly female, with 65% of 2019 new start use among female MS patients. This pattern is seen for both RMS and PPMS, although is more marked for PPMS. Mean age of MS patients initiating OCR has decreased by 4.6 years since 2017. OCR use in those aged ≥56 years has fallen to 12% compared to 31% in 2017. Mean Expanded Disability Status Scale (EDSS) score decreased in the PPMS cohort who initiate OCR therapy, but increased in the RMS cohort.
Among MS individuals who made a first switch to OCR in 2018-2020, more switches were among RMS patients compared to PPMS. Switches to OCR are now most likely from first-line glatiramer acetate (GA; 39%), followed by dimethyl fumarate (18%). Switches from interferon beta have decreased from 33% to 17%. In PPMS, the second most common switch is from another mAb therapy to OCR (accounting for 24% of 2020 switches up from 11% of 2018 switches). First switches to OCR are increasingly among female MS patients (2020: 64% vs. 2018: 50%), especially among PPMS patients. Mean age and EDSS score have not changed significantly over time when assessed by total, MS subtype, or gender.
OCR initiation as a first-line agent is on the rise, driven by increased use among RMS patients, and is being used in younger MS individuals. First-line OCR use in females with PPMS has increased over time. Initial switches to OCR are increasingly coming from GA. The usage pattern of OCR in the United States is evolving and changing over time.