Lupus can lead to arthritis, kidney failure, heart and lung inflammation, central nervous system abnormalities, inflammation of the blood vessels and blood disorders. No new drug for lupus has been approved by regulatory authorities for more than 50 years.

Human Genome Sciences, Inc. (HGS) and GlaxoSmithKline PLC (GSK) announced recently that BENLYSTA™ (belimumab, formerly LymphoStat-B®) has met the primary endpoint in BLISS-52, the first of two pivotal Phase III trials in patients with serologically active systemic lupus erythematosus (SLE). In the placebo-controlled BLISS-52 study, the results showed that BENLYSTA plus standard of care achieved a clinically and statistically significant improvement in patient response rate at Week 52 compared with standard of care alone. Study results also showed that belimumab was generally well tolerated; adverse event rates were comparable between belimumab and placebo treatment groups.

‘The BLISS-52 results support and extend the findings that emerged in the serologically active subgroup of SLE patients at Week 52 in our Phase II trial,’ said David C. Stump, M.D., Executive Vice President, Research and Development, HGS. “We are delighted to report that the efficacy of treatment with BENLYSTA plus standard of care was superior in this study to that of placebo plus standard of care, while the safety profile was comparable overall to placebo.’

Based on an intention-to-treat analysis, belimumab met its primary efficacy endpoint of superiority versus placebo at Week 52. A clinically and statistically significant improvement was shown in patient response rate for belimumab plus standard of care vs. placebo plus standard of care: 57.6% for 10 mg/kg belimumab, 51.7% for 1 mg/kg belimumab, and 43.6% for placebo (p=0.0006 and p=0.011 for 10 mg/kg and 1 mg/kg belimumab, respectively, vs. placebo).

The Phase III development program for belimumab 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 serologically active (i.e. autoantibody-positive) patients with systemic lupus erythematosus. This is the largest clinical trial program ever conducted in lupus patients.

Belimumab is an investigational human monoclonal antibody drug that specifically recognizes and inhibits the biological activity of B-lymphocyte stimulator, or BLyS®. In lupus and certain other autoimmune diseases, elevated levels of BLyS are believed to contribute to the production of autoantibodies – antibodies that attack and destroy the body’s own healthy tissues. The presence of autoantibodies appears to correlate with disease severity. Preclinical and clinical studies suggest that belimumab can reduce autoantibody levels in systemic lupus erythematosus. BLISS-52 results suggest that belimumab can reduce systemic lupus erythematosus disease activity, and a second Phase III trial, BLISS-76, is underway to confirm these results.

For the full version of this story, which includes key findings from BLISS-52 and further information on the BENLYSTA (belimumab) Phase III development program, please see the news section on the HGS website.