Efficacy and safety of four-year ofatumumab treatment in relapsing multiple sclerosis: The ALITHIOS open-label extension.

BACKGROUND

Ofatumumab has demonstrated superior efficacy and favorable safety for up to 2.5 years versus teriflunomide in relapsing multiple sclerosis (RMS).

OBJECTIVE

Further characterize efficacy and safety of ofatumumab in RMS.

METHODS

Efficacy set: patients randomized to ofatumumab/teriflunomide in ASCLEPIOS I/II (core). Safety set: patients who received ⩾ 1 dose of ofatumumab in ASCLEPIOS I/II, APLIOS, APOLITOS (all core), or ALITHIOS (umbrella open-label extension). Patients received continuous ofatumumab or were newly switched from teriflunomide. Data cut-off: 25 September 2021.

RESULTS

In the efficacy set (n = 1882), the continuous ofatumumab group had a low annualized relapse rate (ARR 0.05 (95% confidence interval: 0.04-0.07)), low numbers of gadolinium-enhancing (Gd+) T1 lesions (0.01 lesions/scan) and fewer new/enlarging T2 lesions (annualized rate 0.08). Overall, 78.8% met three-parameter "no evidence of disease activity" criteria through 4 years. Switching from teriflunomide led to reduced ARR, risk of confirmed disability worsening (CDW), new/enlarging T2 lesions, Gd+ T1 lesions, and serum neurofilament light chain. In the continuous and newly switched ofatumumab groups, cumulative 3- and 6-month CDW rates remained low. In the safety set (n = 1969), the most frequently reported adverse events were infections and infestations (58.35%). No new safety signals were identified.

CONCLUSION

Ofatumumab has a favorable longer-term benefit-risk profile in RMS.

TRIAL REGISTRY: ALITHIOS (NCT03650114): https://clinicaltrials.gov/ct2/show/NCT03650114.