A randomized, double‐blind, parallel‐group, placebo‐controlled, multiple‐dose study to evaluate AMG 557 in patients with systemic lupus erythematosus and active lupus arthritis

Systemic lupus erythematosus (SLE) is a autoimmune disease characterized by unpredictable flares on the skin, musculoskeletal, nervous, pulmonary, and renal systems. Currently available treatments are inadequate; hence, more effective therapies with fewer short- and long-term toxicities are needed. Therefore the findings of the present study AMG 557 showed safety and potential effectiveness, supporting further evaluation of the clinical efficacy of ICOSL blockade in patients with SLE. 

To assess a fully human antibody, AMG 557 efficacy and safety inhibit inducible T‐cell costimulator ligand (ICOSL) among the individuals suffered from systemic lupus erythematosus (SLE) with arthritis.

The patients obtained either 210 mg AMG 557 or placebo once a week for three weeks, then every other week for ten additional doses. By day 29, the immunosuppressants were terminated and by day 85, the Corticosteroids were tapered to ≤7.5 mg/day. The Lupus Arthritis Response Index (LARI), medicine discontinuation, ≥1‐letter improvement in the musculoskeletal domain of the British Isles Lupus Assessment Group (BILAG) index, safety and immunogenicity measured at 169 days of the analysis were considered as the primary endpoints. Changes in BILAG index scores, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) along with tender and swollen joint counts were taken as the secondary endpoints.

A total of 1/10 subjects from the placebo group and 3/10 from AMG 557 group showed LARI responses. The rate of ≥4‐point improvement in the SLEDAI was higher in AMG 557 group than placebo. Also, at 169 days the AMG 557 group exhibited more significant improvements in SLEDAI scores, tender and swollen joint counts, and global BILAG index as compared to the placebo. Both groups showed the similar incidences of mild adverse events.

The AMG 557 exhibited safety and potential effectiveness, promoting further assessment of the clinical efficacy of ICOSL blockade among patients with SLE.