THU0114 Effects of smoking on baricitinib efficacy in patients with rheumatoid arthritis: pooled analysis from two phase 3 clinical trials

Background The efficacy of some rheumatoid arthritis (RA) therapies is reduced among patients who are smokers. Objectives This post-hoc analysis of two phase 3 studies assessed the effects of patient smoking status on the response to baricitinib treatment in patients with RA. Methods In RA-BEAM (NCT01710358), patients with inadequate response to methotrexate were randomized to placebo once-daily (QD) (N=488), baricitinib 4 mg QD (N=487), or adalimumab 40 mg biweekly (N=330). 1 In RA-BUILD (NCT01721057), patients with inadequate response to conventional synthetic disease modifying antirheumatic drugs (csDMARDs) were randomized to placebo (N=228) or baricitinib (2 mg, N=229; or 4 mg, N=227) QD. 2 Patients continued background csDMARD therapy in both studies. This post-hoc analysis was conducted in the placebo (N=716) and baricitinib 4 mg (N=714) patients. Patient-reported smoking status was categorized as current (smokers) or not current (non-smokers). Results Among 1,430 evaluable patients who received placebo or baricitinib 4 mg, 290 (20.3%) were smokers. Smoking status at baseline did not affect the clinical results of treatment with baricitinib for 24 weeks; smokers who received placebo were numerically less likely than non-smokers receiving placebo to achieve most clinical outcomes (Table). Baricitinib9s effect on modified total Sharp score was more pronounced among nonsmokers (interaction p-value =0.07). ACR20/50/70=20%, 50%, and 70% improvement in American College of Rheumatology criteria; CDAI=Clinical Disease Activity Index; DAS28-hsCRP=Disease Activity Score 28-high sensitivity C-reactive protein; HAQ-DI=Health Assessment Questionnaire-Disability Index; mTSS=modified total Sharp score; SDAI=Simple Disease Activity Index. Conclusions This analysis of smokers and non-smokers in two RA trials demonstrated that the beneficial effect of baricitinib treatment versus placebo was similar on all clinical endpoints, but may differ for structural damage progression. References Taylor PC et al. Arthritis Rheumatol 2015;67(suppl 10) abst 2L. Dougados M et al. Ann Rheum Dis 2017;76:88–95. Disclosure of Interest J. Curtis Grant/research support from: AbbVie, Amgen, BMS, Janssen, Pfizer, Roche/Genentech, Corrona, UCB, Myriad, Eli Lilly and Company, Consultant for: AbbVie, Amgen, BMS, Janssen, Pfizer, Roche/Genentech, Corrona, UCB, Myriad, Eli Lilly and Company, Employee of: University of Alabama at Birmingham, P. Emery Consultant for: Pfizer, MSD, Abbvie, BMS, UCB, Roche, Novartis, Samsung, Sandoz, Eli Lilly and Company, G. Burmester Consultant for: Eli Lilly and Company, V. Arora Employee of: Eli Lilly and Company, J. Alam Employee of: Eli Lilly and Company, D. Muram Employee of: Eli Lilly and Company, L. Klareskog Grant/research support from: Janssen, Pfizer, BMS, GSK, AbbVie, Roche.