Organ damage, anti-dsDNA antibodies predict belimumab efficacy in lupus
Belimumab treatment for systemic lupus erythematosus (SLE) may induce low disease activity (LDA) and clinical remission in patients with limited or no organ damage, as well as with positive antidouble stranded DNA (anti-dsDNA) titres, according to a study.
The study used data from the BLISS-52 and BLISS-76 trials and included 563 SLE patients (mean age, 37.9 years; 95.7 percent female) who received belimumab 10 mg/kg. Researchers used logistic regression to evaluate the performance of baseline factors in predicting achievement of LDA (assessed using Lupus Low Disease Activity State [LLDAS]) or clinical remission (defined as SLE Disease Activity Index 2000 score of 0) at week 52 from treatment initiation.
Organ damage (assessed using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index [SDI]) reduced the likelihood of attaining LDA (SDI >0: odds ratio (OR), 0.44, 95 percent CI, 0.22–0.90; p=0.024) and the primary LLDAS condition (ie, SLEDAI-2K ≤4 with no renal activity, pleurisy, pericarditis or fever; SDI >1: OR, 0.46, 0.27–0.77; p=0.004). The association between organ damage and failure to achieve the primary LLDAS condition was attributed mainly to cognitive impairment/psychosis prior to belimumab initiation.
Baseline SDI scores >1 also predicted failure to attain clinical remission (OR, 0.53, 0.30–0.94; p=0.030), with cutaneous damage largely driving this association.
On the other hand, anti-dsDNA positivity increased the probability of attaining clinical remission, along with reduced prednisone intake (≤7.5 mg/day), by about 80 percent (OR, 1.82, 1.08–3.06; p=0.025). However, cardiovascular damage reduced the probability of such an outcome (OR, 0.13, 0.02–0.97; p=0.047).
The associations observed were independent of age, SLE disease duration or SLE activity grade, the researchers noted, adding that the data overall have important clinical implications with respect to optimization of the use of belimumab.