Effectiveness and safety of ofatumumab in treatment-naive and oral DMT-switched multiple sclerosis patients: a multicenter observational study in China.

BACKGROUND

Ofatumumab, a fully humanized anti-CD20 monoclonal antibody, is the only highly effective disease modifying therapy (DMT) approved for the treatment of relapsing multiple sclerosis (RMS) in China up to data. Real-world data are necessary to investigate the factors for switching from oral DMTs and to assess the effectiveness and safety of ofatumumab in the Chinese MS population.

OBJECTIVE

We conducted a multicenter observational study (GY2024-038-0) to evaluate the effectiveness and safety of ofatumumab in RMS patients who were either treatment-naïve or had switched from oral DMTs, including teriflunomide, siponimod, fingolimod, dimethyl fumarate.

METHODS

Medical records at three tertiary hospitals were collected between December 2021 and May 2024. Clinical relapses, MRI activity, confirmed disease progression, and adverse events were reviewed.

RESULTS

Treatment-naïve and switched data were obtained for 38 (31.5 % men, mean age 35.42 years, median disease duration 2.31±4.08 years, median follow-up 12.00 months) and 59 (16.9 % men, mean age 34.75 years, median disease duration 5.30±4.17 years, median follow-up 20.00 months) patients, respectively. Among treatment-naïve patients, the annualized relapse rate (ARR) at the final follow-up decreased from 0.27 ± 0.47 to 0.05 ± 0.23 (p < 0.001), while the Expanded Disability Status Scale (EDSS) score at month 12 after treatment dropped from 2.50(2.00-4.00) to 2.00(1.00-3.00) (p < 0.001). For patients switched from oral DMT, the mean reasons for transitioning were disease progression (28.8 %), clinical relapse (28.8 %), MRI activity (25.4 %) and adverse reaction (6.8 %). After switching, ARR and EDSS score at month 12 reduced from 0.45 ± 0.54 to 0.08 ± 0.28(p = 0.039), and from 2.00(2.00-3.38) to 1.00(1.00-2.00) (p < 0.001), respectively. And no increase in T1 Gd-enhancing lesions or new/enlarged T2 lesions identified. No clinical relapses, EDSS worsening, and MRI activity were observed in either treatment-naïve or oral DMT-switched MS patient. During follow-up, no serious adverse events were reported.

CONCLUSIONS

This real-world study revealed a significant decrease in disease activity and progression among MS patients treated with ofatumumab, both in treatment-naïve and oral DMTs-switched patients, while maintaining a well-tolerated safety profile.