OBJECTIVE
To assess the appropriateness of expanded serological activity eligibility criteria for belimumab use in the UK systemic lupus erythematosus (SLE) population (and possibly other countries), which includes patients with either anti-double-stranded DNA (anti-dsDNA) positivity hypocomplementaemia rather than both criteria.
METHODS
This post-hoc analysis used data from three randomised, double-blind, placebo-controlled phase III belimumab trials: BLISS-52 (BEL110752; NCT00424476), BLISS-76 (BEL110751; NCT00410384) and BLISS-SC (BEL112341; NCT01484496). Patients with SLE were stratified by high disease activity (HDA): HDA1, Safety of Estrogens in Lupus Erythematosus National Assessment-SLE Disease Activity Index (SELENA-SLEDAI) score ≥10, low complement positive anti-dsDNA; and HDA2, SELENA-SLEDAI ≥10 and either low complement positive anti-dsDNA.
RESULTS
This analysis included 660 HDA1 patients (n=396 on intravenous treatment; n=264 on subcutaneous treatment) and 969 HDA2 patients (n=532 on intravenous treatment; n=437 on subcutaneous treatment). Significant improvements were observed at week 52 with belimumab versus placebo, irrespective of subgroups or drug formulations, in SLE Responder Index (SRI) 4 response (OR (95% CI): HDA1 intravenous 2.7 (1.8 to 4.1); HDA2 intravenous 2.3 (1.61 to 3.26); HDA1 subcutaneous 2.2 (1.22 to 3.85); HDA2 subcutaneous 1.8 (1.17 to 2.74)); proportion of patients achieving ≥4-point reduction in SELENA-SLEDAI score (OR (95% CI): HDA1 intravenous 2.6 (1.7 to 3.9); HDA2 intravenous 2.1 (1.49 to 3.03); HDA1 subcutaneous 2.3 (1.30 to 4.14); HDA2 subcutaneous 1.9 (1.21 to 2.84)); patients with no worsening in Physician Global Assessment (OR (95% CI): HDA1 intravenous 2.0 (1.3 to 3.1); HDA2 intravenous 1.7 (1.17 to 2.45); HDA1 subcutaneous 2.3 (1.18 to 4.40); HDA2 subcutaneous 1.8 (1.11 to 2.92)); and risk of severe flares (HR (95% CI): HDA1 intravenous 0.6 (0.37 to 0.81); HDA2 intravenous 0.6 (0.43 to 0.86); HDA1 subcutaneous 0.52 (0.30 to 0.92); HDA2 subcutaneous 0.59 (0.37 to 0.94)).
CONCLUSION
Broadening the HDA population to include either low complement positive anti-dsDNA, rather than both, would enable more UK patients to receive SLE treatment and experience improved clinical outcomes.