Efficacy and safety of temelimab in multiple sclerosis: Results of a randomized phase 2b and extension study.

Background: The envelope protein of human endogenous retrovirus W (HERV-W-Env) is expressed by macrophages and microglia, mediating axonal damage in chronic active MS lesions.

Objective And Methods: This phase 2, double-blind, 48-week trial in relapsing-remitting MS with 48-week extension phase assessed the efficacy and safety of temelimab; a monoclonal antibody neutralizing HERV-W-Env. The primary endpoint was the reduction of cumulative gadolinium-enhancing T1-lesions in brain magnetic resonance imaging (MRI) scans at week 24.

A safety and pharmacodynamics study of temelimab, an antipathogenic human endogenous retrovirus type W envelope monoclonal antibody, in patients with type 1 diabetes.

Aim: To report the first study of temelimab, a monoclonal antibody neutralizing the pathogenic human endogenous retrovirus type W envelope, in patients with type 1 diabetes (T1D).

Materials And Methods: This double-blind, placebo-controlled, randomized clinical trial recruited adult patients with T1D within 4 years postdiagnosis and remaining C-peptide secretion. Sixty-four patients were randomized (2:1) to monthly temelimab 6 mg/kg or placebo during 24 weeks followed by a 24-week, open-label extension, during which all patients received temelimab.

A High-dose Pharmacokinetic Study of a New IgG4 Monoclonal Antibody Temelimab/GNbAC1 Antagonist of an Endogenous Retroviral Protein pHERV-W Env.

Purpose: Temelimab/GNbAC1 is a humanized immunoglobulin G4 monoclonal antibody antagonist of the human endogenous retrovirus W envelope protein, which is associated with multiple sclerosis (MS) pathophysiology and possibly with other autoimmune disorders. Human endogenous retrovirus W envelope protein is expressed in the central nervous system of patients with MS, and sufficient amount of temelimab must reach the target. The safety of very high dosages of temelimab should be tested to support further clinical trials in MS.

A new therapeutic approach for type 1 diabetes: Rationale for GNbAC1, an anti-HERV-W-Env monoclonal antibody.

We describe a newly identified therapeutic target for type 1 diabetes (T1D): an envelope protein of endogenous retroviral origin, human endogenous retrovirus W envelope (HERV-W-Env). HERV-W-Env was found to be detected in the blood of ~60% of patients with T1D and is expressed in acinar pancreatic cells of 75% of patients with T1D at post mortem examination. Preclinical experiments showed that this protein displays direct cytotoxicity on human β-islet cells.

A placebo randomized controlled study to test the efficacy and safety of GNbAC1, a monoclonal antibody for the treatment of multiple sclerosis - Rationale and design.

Background: GNbAC1, a humanized monoclonal antibody, is an innovative treatment currently in development for multiple sclerosis (MS) which, contrary to the immunomodulation/immunosuppressive mechanism of action of most of the MS drugs, targets specifically a protein of endogenous retroviral origin supposed to be critical in MS pathogenesis.

Methods: This trial is a randomized placebo controlled 4-arm study with the objective of demonstrating the efficacy of repeated doses of GNbAC1 on the cumulative number of T1 Gd-enhancing lesions measured from Week 12 to 24 in patients with relapsing remitting MS (RRMS). Two hundred sixty patients with RRMS are planned to be included.