Tumor necrosis factor (TNF) and interleukin-17A (IL-17A) may independently contribute to the pathophysiology of rheumatoid arthritis (RA). This study sought to evaluate the safety and efficacy of ABT-122, a novel dual variable domain immunoglobulin targeting human TNF and IL-17A, in patients with RA who have experienced an inadequate response to methotrexate.
Patients with active RA who were receiving treatment with methotrexate and had no prior exposure to biologic agents (n = 222) were enrolled in a 12-week phase II randomized, double-blind, active-controlled, parallel-group study. Patients were randomized to receive either ABT-122 at dosages of 60 mg every other week, 120 mg every other week, or 120 mg every week or adalimumab at 40 mg every other week, administered subcutaneously. The primary efficacy end point was the proportion of patients achieving a ≥20% improvement response based on the American College of Rheumatology criteria for 20% improvement (ACR20) at week 12.
Treatment-emergent adverse events were similar across all treatment groups, with no serious infections or systemic hypersensitivity reactions reported with ABT-122. ACR20 response rates at week 12 were 62%, 75%, and 80% with ABT-122 60 mg every other week, 120 mg every other week, and 120 mg every week, respectively, compared with an ACR20 response rate of 68% with 40 mg adalimumab every other week. The corresponding response rates for ACR50 and ACR70 improvement in the ABT-122 dose groups and adalimumab group were 35%, 46%, 47%, and 48%, respectively, and 22%, 18%, 36%, and 21%, respectively.
Over the 12-week study period, dual inhibition of TNF and IL-17A with ABT-122 produced a safety profile consistent with that of adalimumb used for inhibition of TNF alone. The efficacy of ABT-122 over 12 weeks at dosages of 120 mg every other week or 120 mg every week was not meaningfully differentiated from that of adalimumab at a dosage of 40 mg every other week in patients with RA receiving concomitant methotrexate.