AB0752 Efficacy and Safety of Brodalumab over One Year in Patients with Psoriatic Arthritis with and without Prior Exposure to A Biologic

Background New agents with novel mechanisms of action are needed to treat the growing pool of patients with psoriatic arthritis (PsA) who do not respond to, lose response to, or do not tolerate biologics. Patients with PsA who fail one tumor necrosis factor inhibitor (TNFi) often demonstrate reduced treatment response to subsequent TNFi's. Objectives To compare the long-term efficacy at weeks 12, 24, and 52 and safety of brodalumab in biologic-naïve vs. biologic-experienced patients with PsA. Methods Patients between 18 – 75 years with active PsA (Classification of Psoriatic Arthritis criteria with ≥3 tender and ≥3 swollen joints) for ≥6 months were randomly assigned (1:1:1) to receive double-blind placebo or brodalumab (140 or 280 mg Q2W); at week 12, patients could enter an open-label extension to receive 280 mg Q2W brodalumab. As observed American College of Rheumatology (ACR) response rates, and changes from baseline in Disease Activity Score (28 joint count C-reactive Protein [DAS28CRP]) and enthesitis and dactylitis counts were analyzed. Results A total of 168 patients were randomized (naïve N=82; experienced N=86); 156 entered the open-label phase. Patients were similar in baseline demographics, disease characteristics, and mean baseline doses of methotrexate (19 vs. 18 mg/wk), although PsA duration was slightly less in the naïve group (7 vs. 10 years). Approximately 97% of the experienced patients had used a TNFi; based on medication history, 54% were primary failures, 6% secondary failures, while the rest discontinued due to intolerance (10%) or other non-specified reasons (30%). ACR response rates were comparable between naïve and experienced patients at weeks 12, 24, and 52 (Table). The groups were also comparable in mean change from baseline in DAS28-CRP, enthesitis, and dactylitis. There was no difference in tolerability of brodalumab between the groups, with 91% (n/N=71/78) of both naïve and experienced patients reporting an adverse event, and 9% (n/N=7/78) and 4% (n/N=3/78) of patients experiencing a serious adverse event in the open-label phase. Conclusions Prior exposure to a biologic does not seem to affect the efficacy or tolerability of brodalumab over one year in the treatment of PsA. Acknowledgements This study was funded by Amgen, Inc. Disclosure of Interest M. Genovese Grant/research support: Amgen, Inc, Consultant for: Amgen, Inc, P. Mease Grant/research support: (Abbott) AbbVie, Amgen, Biogen Idec, BMS, Celgene, Crescendo, Genente