Safety Board Says Phase 2 Temelimab Trial Should Move Forward

A Phase 2a clinical trial evaluating GeNeuro‘s investigational antibody temelimab as a treatment for relapsing multiple sclerosis (MS) should continue as planned, without modifications.

That’s the recommendation of a Drug Safety Monitoring Board, an independent committee of clinical research experts, which was evaluating the trial of the relapsing MS therapy candidate, the company announced in a press release.

The board’s recommendation was based on data from the first eight patients who received temelimab for two months in the ProTEct-MS trial (NCT04480307). The study is ongoing at the Karolinska Institutet’s Academic Specialist Center in Stockholm, Sweden.

Patient enrollment recently was completed for the double-blind trial, in which neither researchers nor participants know which patients are receiving the therapy and which the placebo. Top-line results are expected by March 2022.

Temelimab is a monoclonal antibody specifically designed to target a viral protein — called pHERV-W — preventing it from activating an immune response and causing damage to the myelin coat that surrounds nerve cells, two hallmarks of MS.

ProTEct-MS is a randomized trial designed to investigate the safety and effectiveness of temelimab in patients with relapsing forms of MS, whose disability progressed without relapses, and who had previously been treated with rituximab for at least one year.

Rituximab is an antibody that targets a protein on the surface of B-cells — a type of immune cell that starts inflammation in MS — triggering their death. The medication, approved for certain blood cancers, is used off-label in MS and has been shown to be highly powerful and effective in treating relapses and brain lesion formation.

A total of 42 patients were enrolled in the study and randomly assigned to receive one of three temelimab doses (18, 36, or 54 mg/kg) or a placebo, given as a monthly intravenous or into-the-vein infusion for two years.

As its primary goal, the trial will assess the safety and tolerability of temelimab, measured as the number of adverse events experienced by patients. Additional goals include measuring how the therapy impacts brain atrophy (shrinkage) and lesion volume, both assessed by neuroimaging.

Researchers have already reported positive results with temelimab in the CHANGE-MS Phase 2 trial (NCT02782858) and the open-label extension study ANGEL-MS (NCT03239860). In both studies, treatment with an 18 mg/kg dose reduced brain atrophy, helped maintain the integrity of myelin, and reduced disease progression.

“Our previous clinical studies have demonstrated that temelimab administration is safe and demonstrated positive results on markers of disability progression at 18 mg/kg in patients, so it is now important to define the optimal dose in preparation for the planned Phase III study,” said David Leppert, MD, chief medical officer of GeNeuro.

“We are delighted to have the tolerability of the higher doses of temelimab confirmed as a further step in our path to deliver a treatment against the critical unmet medical need of blocking disability progression in MS,” Leppert added.