A subcutaneous formulation of GlaxoSmithKline’s Benlysta has hit targets in a Phase III trial involving patients with active, autoantibody-positive systemic lupus erythematosus.

Findings from the BLISS-SC study presented at the American College of Rheumatology/Association for Rheumatology Health Professionals Annual Meeting show that weekly subcutaneous infusions of Benlysta (belimumab) plus standard of care achieved greater reductions in disease activity compared to placebo/SoC.

For the primary efficacy endpoint - Systemic Lupus Erythematosus Responder Index (SRI)* at Week 52 - 60.8% of patients treated with GSK’s drug plus SoC showed reduced disease activity versus 48.47% of those receiving placebo/SoC. 

The Benlysta regimen also met the secondary target of delaying the time to severe flare (170 days) versus placebo/SoC (116.5 days), and while 18.2% were able to reduce their steroid dose by 25% or more (in those taking more than 7.5mg/day of prednisone) compared to 11.9% of those on placebo/SoC, this did not reach statistical significance.

Highlighting the need for new treatment options, Paul-Peter Tak, head of the Immuno-Inflammation Therapy Area Unit at GSK, noted that despite use of current standard of care, such as glucocorticosteroids and immunosuppressants, “about 60% of lupus patients continue to experience persistent symptoms and severe disease flares”.

Results of the trial “reinforce our belief in the BLyS pathway as a means of reducing underlying disease activity,” and “we expect to progress towards global regulatory filings for a belimumab subcutaneous formulation, which if approved, will provide appropriate patients with a new approach to treatment administration,” he said.

Benlysta is the first medicine specifically developed and approved for SLE in over 50 years. It is a human monoclonal antibody that selectively targets B-lymphocyte stimulator (BLyS), an important factor in the survival of B cells. 

Intravenous formulations of the drug are approved in the US for the treatment of adults with active, autoantibody_positive, SLE receiving standard therapy, and in the European Union as an add-on therapy in adults with a high degree of disease activity, despite standard therapy.

*SRI is a composite endpoint measuring clinical improvement (SELENA-SLEDAI) with no significant worsening in any organ system (BILAG) and no worsening in overall patient condition (PGA).