Objectives:To investigate predictors of drug survival of bDMARDs in previously bio-naive patients (pts) with RA during the first year of therapy.Methods:204 adult bio-naive pts (173 women, 84.8%), with active RA, despite the concomitant DMARD therapy, were included into retrospective study. All of them initiated bDMARDs: infliximab (INF) - 65 pts (31.9%), rituximab (RTM) - 39 (19.1%), adalimumab (ADA) - 30 (14.7%), etanercept (ETA) - 28 (13.7%), abatacept (ABA) - 23 (11.3%), tocilizumab (TZ) - 15 (7.4%), certolizumab pegol - 4 (1.9%). The following indicators were used as survival predictors: sex, age and clinical form of RA. Pts were divided by age according to the classification adopted by the World Health Organization: 18-44 years (74 pts), 45-59 years (68 pts), 60-74 years (57 pts), 75 years or more (5 pts). Clinical forms of RA were presented: RA, seropositive by rheumatoid factor (RF), RA, seronegative by RF, RA with extra-articular manifestations, adult-oneset Still’s disease, juvenile RA. Predictors of therapy inefficiency or AE were investigated in Cox proportional risk model. Survival on drug was estimated using the Kaplan-Meier method and evaluation of difference significance using log-rank criterion.Results:A year later, 92 pts (45%) remained on bDMARDs and 112 pts had their treatment discontinued. The reasons of bDMARDs discontinuation during the first year of treatment were: lack of effectiveness (including primary inefficiency) - 50%, adverse events (AE) - 25%, administrative causes - 17%, remission - 6.25%, death due to reasons unrelated to the therapy - 1.75%. By the end of the observation period, the best survival was shown by RTM therapy (69.23% of patients continued treatment for a year), ETA (44.4% of patients) and ABA (43.48% of patients). Discontinuation of bDMARDs due to remission was achieved in 7 patients and proved to be significantly higher in the RTM group (10.26%, p < 0.05) compared to the ABA group (8.7%) and ADA group (3.45%). Although the number of women continued after a year was significantly higher than that of men (84.8% and 15.2% respectively), female sex was not a reliable predictor of drug survival. At the same time, the rate of discontinuation due to AE in women was higher (96.55%, p = 0.03). After a year, the number of pts continuing treatment in all age groups remained comparable, and the difference between them - statistically not significant: 1 group (18-44 years old, 29 pts) - 31.52% of pts, 2 group (45-59 years old, 36 pts) - 39.13%, 3 group (60-74 years old, 26 pts) - 28.26%, 4 group (75-90 years old, 1 pts). Discontinuation of bDMARDs due to inefficiency was noted in 1 group more often (46.43%, 26 pts, р =0.03), in other groups this indicator was 33.93% (19 pts) in the 2nd group, 19.64% (11 pts) in the 3rd group and 0% in the 4th group. Discontinuation therapy due to AE was also prevalent in 1 group (50%, 14 pts) than in 2 (14.3%, 4 pts), 3 (32.1%, 9 pts) and 4 (3.6%, 1 pts). Discontinuation of therapy due to inefficacy was more common in the group of seronegative RA - 59.1% (p < 0.05). In the seropositive RA group 24.8% of pts had interrupted bDMARDs for this reason, in the RA with extra-articular manifestations group it was 18.1%, in the adult-oneset Still’s disease group - 30% and in the juvenile RA group - 30%. Discontinuation of therapy due to remission was overwhelmingly observed in seropositive RA group (6 pts, 4%) and was significantly higher than in other groups (1 patient in RA with extra-articular manifestations group, 4.5%).Conclusion:Female sex, young age (18-44 years), RA, seronegative by RF were associated with less survival of bDMARDs due to lack of effectiveness and/or AE, and RTM and seropositive RA - with more frequency of discontinuation of therapy due to remission.Disclosure of Interests:Eugenia Aronova: None declared, Galina Lukina Speakers bureau: Novartis, Pfizer, UCB, Abbvie, Biocad, MSD, Roche, Galina Gridneva: None declared, Svetlana Glukhova: None declared, Anastasia Kudryavtseva: None declared