Stiefel, a GSK company, announced the start of a phase III study to evaluate the efficacy and safety of subcutaneous of atumumab in patients with pemphigus vulgaris, a rare autoimmune skin disorder. The global study will assess disease remission in patients with pemphigus vulgaris treated with subcutaneous ofatumumab as add-on treatment to oral steroids, the global standard-of-care.

Pemphigus vulgaris is a rare, chronic skin disorder in which the immune system malfunctions and produces antibodies that attack healthy cells in the skin and mucous membranes.1 Patients with pemphigus vulgaris develop burn-like blisters, which can first appear in the mouth and then on the skin. Typically occurring between the ages of 30 to 60 years, pemphigus vulgaris can lead to secondary skin infections, dehydration, spread of infection through the blood (sepsis) and death. The incidence of pemphigus vulgaris is approximately 7 people per million worldwide. The global standard treatment for pemphigus vulgaris is chronic, high-dose systemic steroids.

“The initiation of this study is an important step towards providing a potential new treatment option for patients suffering from this painful and potentially debilitating skin disease,” said Dr. Kathy Rouan, senior vice president and head of R&D, Stiefel.

This global, multicentre, randomised, double-blind, placebo-controlled, parallel-group study (OPV116910) will assess the efficacy, safety, and tolerability of subcutaneous ofatumumab in subjects with pemphigus vulgaris.

The primary objective of the study is to determine disease remission, following treatment with subcutaneous ofatumumab as add-on treatment to oral steroids (which will gradually be reduced) compared to a control arm receiving placebo as add-on treatment. Subcutaneous ofatumumab will be administered at a dose of 20 mg every four weeks (following two initial loading doses) for a total of 56 weeks. Secondary objectives include evaluation of safety, tolerability, B-cell depletion and repletion, anti-desmoglein antibody levels, immunogenicity, pharmacokinetics, and other clinical and quality of life endpoints.

Ofatumumab is a human monoclonal antibody which targets an epitope on the CD20 molecule encompassing parts of the small and large extracellular loops. Ofatumumab is being developed under a co-development and collaboration agreement between Genmab and GSK. Under the companies' agreement, GSK is solely responsible for development of ofatumumab in autoimmune indications and all related costs. Ofatumumab is not approved or licensed anywhere in the world for pemphigus vulgaris.