Safety and efficacy of belimumab in older adults with SLE: results of an integrated analysis of clinical trial data.

Objective: Assess the safety and efficacy of belimumab in older adults with SLE.

Methods: This post hoc integrated analysis (GSK Study 116559) included safety data from six randomised, placebo-controlled belimumab trials (BLISS-76, BLISS-52, BLISS-SC, North East Asia study, LBSL02, EMBRACE; n=4170). The BASE study provided additional safety data (n=4003). Efficacy data were from five of the trials. Older adults (≥65 years) were compared with the overall populations of patients with SLE. Patients who had received ≥1 treatment dose were included.

Results: Sixty-three older adults (1.5%) were included in the pooled safety analysis population and 156 (3.9%) in the BASE study. At baseline, older adults had lower disease activity but more organ damage than the overall populations. In the pooled safety analysis population, five (18.5%) placebo-treated and ten (27.8%) belimumab-treated older adults experienced ≥1 serious adverse event (SAE), as did 230 (17.0%) placebo-treated and 421 (15.0%) belimumab-treated patients overall. In the BASE study, nine (11.0%) placebo-treated and six (8.1%) belimumab-treated older adults experienced ≥1 SAE, as did 222 (11.1%) placebo-treated and 220 (11.0%) belimumab-treated patients overall. No clinically relevant differences in deaths and adverse events of special interest were observed between older adults and the overall populations. Older adults' SLE Responder Index response rates favoured belimumab versus placebo, consistent with the overall population.

Conclusion: The safety and efficacy of belimumab in older adults were generally consistent with the overall populations, suggesting belimumab is a treatment option for older patients with SLE. Due to small numbers of older adults, findings should be interpreted with caution.