27475 Efficacy of the BIIB059 monoclonal antibody against BDCA2 in active cutaneous lupus erythematosus (CLE): Subgroup analyses of participants with or without systemic LE (SLE) and with different levels of disease activity

Abstract

CLE is an autoimmune disease occurring with or without systemic manifestations that significantly impairs health-related QoL. In the phase 2 LILAC (NCT02847598) study (part B), efficacy of BIIB059 50mg, 150mg, and 450mg vs placebo SC Q4W was demonstrated in participants with CLASI-A scores ≥8 and ≥1 subacute and/or chronic CLE lesions. In the subgroup analyses presented here, percentage changes from baseline in CLASI-A scores were analyzed in CLE participants with vs without concomitant SLE and in those with baseline CLASI-A<10 vs ≥10. The overall modified intent-to-treat population consisted of n = 33 (placebo), n = 26 (BIIB059 50mg), n = 25 (BIIB059 150mg), and n = 48 (BIIB059 450mg). The least squares (LS) mean differences from placebo (95%CI) in percentage change in CLASI-A at week 16 for participants with SLE were -31.01 (-61.61,-0.41; n = 11; BIIB059 50mg), -34.93 (-63.86,-6.00; n = 12; BIIB059 150mg), and -19.04 (-44.44,6.35; n = 20; BIIB059 450mg). For participants without SLE, they were -21.08 (-47.00,4.84; n = 15; BIIB059 50mg), -33.58 (-60.36,-6.79; n = 13; BIIB059 150mg), and -36.52 (-59.09,-13.95; n = 28; BIIB059 450mg). The LS mean differences from placebo (95%CI) in percentage change in CLASI-A at week 16 for participants with CLASI-A<10 were 25.38 (58.82,8.06; n = 6; BIIB059 50mg), 59.37 (97.19,21.55; n = 4; BIIB059 150mg), and 28.64 (59.67,2.39; n = 8; BIIB059 450mg). For CLASI-A≥10, they were 23.48 (47.00,0.05; n = 20; BIIB059 50mg), 28.08 (50.72,5.44; n = 21; BIIB059 150mg), and 26.21 (45.91,6.51; n = 40; BIIB059 450mg). The incidence of AEs in the overall study population was similar between the placebo and BIIB059 groups. Although the subgroup analyses are limited by small sample sizes and are not powered for statistical testing, BIIB059 efficacy was observed regardless of SLE presence or disease severity, consistent with the primary analysis in part B of the LILAC study.