# Switch from intravenous anti-CD20 therapy to subcutaneous ofatumumab in patients with relapsing MS: results from the OLIKOS study

## TL;DR

This study shows that switching from intravenous anti-CD20 therapy to subcutaneous ofatumumab in MS patients maintains effectiveness and safety while improving treatment satisfaction.

## Contribution

The study provides first evidence on efficacy and safety of switching from IV to SC anti-CD20 therapy in relapsing MS.

## Key findings

- Zero Gd+ T1 lesions observed at 12 months in most participants.
- Treatment satisfaction improved significantly, especially in the Convenience domain.
- No new safety signals were identified during the study.

## Abstract

Multiple sclerosis (MS) is a chronic condition, and as such, switching therapies is not uncommon. However, data on switching from intravenous (IV) to subcutaneous (SC) formulations of anti-CD20 therapies are lacking.

OLIKOS, a phase 3b, prospective, single-arm, multicenter study conducted from 2020 to 2024, evaluated the efficacy and safety of switching to SC ofatumumab from IV ocrelizumab or rituximab in adults with relapsing MS. Participants were excluded if they had discontinued anti-CD20 therapy due to suboptimal response or safety concerns. Maintenance of efficacy was defined as either no change or a reduction from baseline in the number of gadolinium-enhancing (Gd +) T1 lesions observed by magnetic resonance imaging (MRI) after 12 months of ofatumumab.

The full analysis set included 102 participants. Most participants (99%) switched from IV ocrelizumab to SC ofatumumab. Zero Gd+ T1 lesions were observed at Month 12 in participants with evaluable MRI assessments (n = 84), satisfying the primary endpoint. New/enlarging T2 lesions were observed in 2.3% (2/86) of participants at Month 12. There was no change in median Expanded Disability Status Scale score between baseline and Month 12, and annualized relapse rate remained low (0.075). Treatment satisfaction improved from baseline to Month 12 across all domains with the largest increases in the Convenience domain. Treatment-emergent adverse events occurred at similar frequencies as in ofatumumab phase 3 trials, and no new safety signals were identified.

The findings indicate efficacy and safety are maintained following a switch from IV anti-CD20 to SC ofatumumab with improved treatment satisfaction.

ClinicalTrials.gov Identifier: NCT04486716 https://clinicaltrials.gov/study/NCT04486716

The online version of this article (10.1007/s00415-025-13462-w) contains supplementary material, which is available to authorized users.