Belimumab is being developed by Human Genome Sciences (HGS) and GlaxoSmithKline (GSK) under a co-development and commercialization agreement entered into in August 2006.
The belimumab Phase III development program includes two double-blind, placebo-controlled, multi-center Phase III superiority trials – Bliss-52 and Bliss-76 – to evaluate the efficacy and safety of belimumab plus standard of care, versus placebo plus standard of care, in patients with serologically active systemic lupus erythematosus (SLE).
The design of the two trials is similar, but the duration of therapy in the two studies is different – 52 weeks for Bliss-52 and 76 weeks for Bliss-76. The data from Bliss-76 will be analyzed after 52 weeks in support of a potential biologics license application. HGS said that the company designed the belimumab Phase III program in collaboration with GSK and leading international SLE experts. The primary efficacy endpoint of Bliss-52 and Bliss-76 is the patient response rate at week 52.
In each of the two Phase III trials, patients have been randomized to one of three treatment groups: 1mg/kg belimumab, 10mg/kg belimumab, or placebo. Patients are dosed intravenously on days zero, 14 and 28, then every 28 days for the duration of the study. All receive standard of care therapy in addition to the study medication. Safety and tolerability are evaluated by an independent data monitoring committee throughout both studies.