OLIKOS, a 12-month, prospective, single-arm, multicenter Phase 3b study, will explore maintained efficacy in patients with relapsing multiple sclerosis (RMS) transitioning from intravenous anti-CD20 monoclonal antibody (mAb) therapy to ofatumumab.

B-cell depletion in RMS patients using anti-CD20 mAbs reduces annualized relapse rates and inflammatory lesion activity on MRI, and delays time to confirmed disability worsening. Anti-CD20 mAbs ocrelizumab and rituximab are administered intravenously in clinic; ofatumumab is administered subcutaneously with an autoinjector pen, facilitating patient-administration at home. No outcome data exist relating to transition from ocrelizumab/rituximab treatment to ofatumumab.

Approximately 100 adults with RMS will be enrolled at 10-20 US centers. Eligible patients will have been previously treated with 2-5 consecutive courses of ocrelizumab/rituximab, with last dose 4-9 months before OLIKOS baseline. Other inclusion criteria are EDSS score ≤5.5 at screening and CD19 B-cell count <1% normal at baseline. Patients with suboptimal response to anti-CD20 therapy in the previous 6 months (relapse, ≥2 active gadolinium-enhancing [Gd+] lesions, any new/enlarging T2 lesions, clinical worsening), or who discontinued anti-CD20 therapy because of severe infusion-related reactions or recurrent infections, or with progressive disease, will be excluded. All participants will receive ofatumumab 20mg via autoinjector on Days 1, 7, and 14, then every 4 weeks through Month 12. The primary endpoint will be no change or a reduction in Gd+ lesion count at Month 12. Secondary endpoints will be participant retention and changes in immune biomarkers, treatment satisfaction, safety, and tolerability at Months 6 and 12. There will be a 6-month interim analysis.

The detailed study design for the OLIKOS trial will be presented. The trial will generate efficacy, retention, and satisfaction data from RMS patients transitioning from intravenous anti-CD20 therapies to ofatumumab.

OLIKOS will provide important data on the maintenance of efficacy in RMS patients transitioning from intravenous anti-CD20 therapies to ofatumumab.