GSK announces positive results in fourth consecutive pivotal trial of Benlysta in SLE

Data in Japan, China and South Korea will form basis of new regulatory submissions for Benlysta.

For the primary efficacy endpoint (SLE Responder Index at Week 52), significantly more of the patients on belimumab 10 mg/kg administered intravenously (54%) achieved reduced disease activity compared with those on placebo (40%). SRI is a comprehensive composite endpoint measure, the components of which measure reduction in disease activity defined as clinical improvement (less than or equal to 4-point improvement in SELENA-SLEDAI, [SS]) with no significant worsening in any organ system (BILAG) and no worsening in overall patient condition (PGA).

The benefits of belimumab were also seen for all the secondary endpoints in the study. The key secondary endpoint relating to average steroid reduction in patients with baseline dose of >7.5 mg/day prednisone was significant, favouring belimumab. In addition, 56% of patients on belimumab achieved a greater than or equal to 4 point reduction in SS at Week 52; 33% of belimumab patients achieved an SRI7 response rate; and the belimumab group had a 50% lower risk of experiencing a severe flare versus placebo, as measured by the Severe Flare Index.

The safety profile of belimumab observed in the study was consistent with that observed in previous IV and subcutaneous belimumab studies, with the overall incidence of adverse events being similar in both the belimumab (75%) versus placebo (76%) groups. Fewer serious adverse events occurred in the belimumab group compared with the placebo group (12% versus 18%). There were no deaths in the belimumab group and 1 in the placebo group. No new safety issues were identified.

David Roth, Project Lead for Benlysta at GSK, said: "Outside of South Korea, where Benlysta has already been granted approval, there is currently no approved biologic treatment option for lupus patients in Northeast Asia, so in the context of the unmet medical need in the region, this study result is extremely important. The data also reinforces our belief that the belimumab mechanism of action is central to disease activity in SLE and we are pleased that the benefit/risk profile remains favourable for patients. Based on this data and subsequent regulatory submissions, we hope to be able to make Benlysta available to more patients living with lupus in this region."