Real-world use of ofatumumab to treat multiple sclerosis 9 months post-FDA approval during COVID-19 pandemic

Abstract

Background: Relapsing multiple sclerosis (MS) is an inflammatory, demyelinating, neurodegenerative disease of the central nervous system that causes episodes of neurological dysfunction (relapse) alternating with variable intervals of stability. Disease-modifying therapies (DMTs) aim to reduce the rate of relapse and slow disease progression in people with MS, particularly in those with relapsing MS. Ofatumumab is a fully human anti-CD20 monoclonal antibody approved to treat patients with relapsing forms of MS. This study describes the demographics, clinical characteristics, and prior DMT use of patients with at least one ofatumumab prescription claim following approval by the United States (US) Food and Drug Administration (FDA). Understanding ofatumumab utilization patterns and patient characteristics can help define the journey of patients with MS and aid future clinical decision-making.

Methods: This retrospective study is based on data from IQVIA's Longitudinal Prescription Data (LRx) and Medical Claims (Dx) databases in the US, collected between August 01, 2019 and May 31, 2021. The index date was defined as the date of the first ofatumumab prescription. The pre-index period was defined as the 12 months prior to the index date. Adult patients (aged ≥18 years) with a diagnosis of MS and at least one prescription for ofatumumab between August 2020 and May 2021 in the LRx database were included. Only patients with at least one medical claim in the Dx database and a diagnosis of MS 24 months prior to the index date were included. Descriptive analyses were conducted 3, 6, and 9 months after FDA approval.

Results: Overall, 3,600 patients with a prescription for ofatumumab were identified in the LRx claims database, and 2,101 patients remained in the study after inclusion and exclusion criteria had been applied. At the 9-month post-approval time point, patients with ofatumumab claims were characterized as primarily female (74%) and middle-aged (median age: 48 years); two-thirds (64.7%) had a mild MS disability level. Patients were otherwise generally healthy with limited comorbid conditions. Most patients (81.7%) in the study did not experience relapse during the pre-index period. DMT-naïve patients who were prescribed ofatumumab at 3, 6, and 9 months post-approval accounted for 46.9%, 54.8%, and 58.4% of the study population, respectively. Over time, this increase in DMT-naïve ofatumumab initiators was statistically significant (p = 0.0003). Among patients who had been treated with DMTs during the previous year, most had taken them orally (50.6%), some had received them via intravenous infusion (32.2%), and some via subcutaneous/intramuscular injection (21.1%). Intravenous ocrelizumab was the most common DMT switch observed (n = 205, 23.4%) among these patients.

Conclusion: This real-world study is the first to describe patients treated with ofatumumab since FDA approval during the COVID-19 pandemic. The majority of patients in this study were middle-aged women with mild MS symptoms. Ofatumumab was increasingly used as a first-line DMT. Additionally, a number of patients aged ≥55 years (beyond the trial population) used ofatumumab, which may suggest expanding clinician confidence in the safety and clinical utility of ofatumumab therapy. However, future long-term observational studies are needed to confirm these results.

Keywords: Anti-CD20 human MAb; DMT-naïve; Disease-modifying therapies; Drug utilization; Relapsing multiple sclerosis.