Genmab to Begin Phase 3 Trials of Ofatumumab to Treat Relapsing Multiple Sclerosis

Genmab announced plans to soon begin a Phase 3 clinical trial program assessing the subcutaneous formulation of ofatumumab as a potential treatment for relapsing multiple sclerosis (MS). The company, working in collaboration with its partner Novartis, will begin enrolling patients in September in trials that will evaluate the efficacy and safety of ofatumumab compared to teriflunomide (Aubagio), an approved relapsing MS treatment.

Ofatumumab is a human monoclonal antibody targeting an epitope in the CD20 molecule, which is found on the surface of B-cells, important immune cells that are involved in the pathogenesis of MS and also cancer. By targeting CD20, ofatumumab is able to direct the body’s immune system to fight normal and cancerous B-cells.

The Phase 3 trials (ASCLEPIOS I and II studies) are randomized, double-blind studies to compare the safety and efficacy of ofatumumab versus teriflunomide, in approximately 900 patients with relapsing MS in each study. Patients will be randomized to receive either subcutaneous injections of ofatumumab every four weeks, or teriflunomide orally once daily. The trials’ primary endpoint is the annualized relapse rate (ARR), meaning the number of confirmed relapses in a 12-month period. Novartis will be conducting the studies.

“Ofatumumab has the potential to be a best-in-class anti B-cell therapy for relapsing MS,” Jan van de Winkel, PhD, chief executive officer of Genmab, said in a press release. “We look forward to swift execution and outcome of these trials and to further development of ofatumumab in this disease area.”

A Phase 2 clinical trial for relapsing-remitting MS (RRMS) investigating the subcutaneous formulation of ofatumumab has been completed, and top-line results demonstrated significant reduction in the cumulative number of new brain lesions, according to a Genmab statement.

Ofatumumab, under the trade name Arzerra, is currently approved in the United States, in combination with chlorambucil, for the treatment of previously untreated patients with chronic lymphocytic leukemia (CLL) for whom fludarabine-based therapy is considered inappropriate.

More information on the planned Phase 3 studies is expected to be available soon.

MS is a demyelinating disease of unknown etiology in which the insulating covers (myelin) of nerve cells in the brain and spinal cord are damaged. This damage disrupts the ability of parts of the nervous system to communicate, resulting in a range of signs and symptoms, including physical, mental, and sometimes psychiatric problems.

MS affects approximately 2.5 million people worldwide. The most common form of MS, accounting for 80% of the cases, is RRMS, which is characterized by unpredictable recurrent attacks where the symptoms usually evolve over days and are followed by either complete, partial or no neurological recovery. No progression of neurological impairment is experienced between attacks.