FDA Grants Orphan Drug Designation to Belimumab for Systemic Sclerosis Treatment

The FDA has granted Orphan Drug Designation to belimumab (Benlysta; GSK) for the potential treatment of systemic sclerosis.

Systemic sclerosis, which affects just 2.3 to 10 people per 1 million, is characterized by microvascular damage, dysregulation of immunity, and progressive fibrosis in multiple organs. Interstitial lung disease is a common and serious complication of systemic sclerosis, marked by inflammation and buildup of scar tissue in the lungs. It is observed in as many as half of patients with systemic sclerosis and is a significant contributor to patients’ disease burden and mortality.

According to a press release, the company plans to initiate a phase 2/3 trial of belimumab for systemic sclerosis associated with interstitial lung disease in the first half of 2023. Systemic sclerosis is a rare autoimmune disease that causes atypical growth of connective tissues and can affect the musculoskeletal system, heart, lungs, kidneys, skin, and other organs. Interstitial lung disease is the leading cause of death in systemic sclerosis, affecting as many as half of people living with the disease, according to the press release.

Systemic sclerosis associated with interstitial lung disease has limited treatment options, and the Orphan Drug Designation reflects the need for new research and developments for this patient population. The designation is granted to support the development and evaluation of potential new treatments intended for the treatment, diagnosis, or prevention of rare diseases and disorders affecting fewer than 200,000 patients in the United States.

Belimumab is a B-lymphocyte stimulator (BLyS) specific inhibitor that binds to soluble BLyS, which is increased in patients with systemic autoimmune diseases such as systemic lupus erythematosus and lupus nephritis. As a fully human monoclonal antibody, it inhibits the prolonged survival of B cells induced by increased BLyS, including autoreactive B cells, and reduces the differentiation of B cells into immunoglobulin-producing plasma cells.

Belimumab was first approved by the FDA for the treatment of active systemic lupus erythematosus. It is the first and only approved biologic for this indication and lupus nephritis in more than 50 years, including for pediatric patients, according to the press release.

REFERENCE

Benlysta granted Orphan Drug Designation by US FDA for the potential treatment of systemic sclerosis. GSK; February 1, 2023. Accessed February 3, 2023. https://www.gsk.com/en-gb/media/press-releases/benlysta-granted-orphan-drug-designation-by-us-fda-for-the-potential-treatment-of-systemic-sclerosis/