LAUSR

Background Baricitinib (bari) demonstrated clinical efficacy in Ph3 trials in RA patients (pts) naïve to DMARDs (RA-BEGIN1); and in RA pts with inadequate response to conventional synthetic DMARDs (RA-BEAM2 and RA-BUILD3) or biologic DMARDs (RA-BEACON4). Objectives To evaluate durability and maintenance of efficacy over an additional 96 weeks (wks) of bari treatment. Methods Pts included were those randomised to bari in an originating study (OS), completed that study without rescue (52 wks in RA-BEGIN or RA-BEAM; 24 wks in RA-BUILD or RA-BEACON), and entered the long-term extension (LTE) study ≥96 wks prior to data cut-off. Durability of response was evaluated as pts achieving low disease activity (LDA) of SDAI ≤11 and minimal clinically important difference (MCID) of HAQ-DI improvement ≥0.22. Maintenance of response was evaluated as proportion of pts who had responded to bari at entry into LTE and maintained response at wk 96. Data are also provided for pts who had not responded to bari at entry into LTE who achieved response. Results Approximately half the pts in the durability analyses were categorised as LDA by wk 24 and the proportion of pts in the LDA category were similar or higher at wk 96. Three quarters of pts across groups demonstrated HAQ-DI improvement by wk 12 and more than half achieved MCID at wk 96. Most responders at entry into LTE maintained their response through wk 96. More than 25% of SDAI and HAQ-DI nonresponders at entry into LTE achieved response after 96 wks of treatment.Table 1 RA-BEGIN RA-BEAM RA-BUILD RA-BUILD RA-BEACON RA-BEACON Bari 4mg Bari 4mg Bari 2mg Bari 4mg Bari 2mg Bari 4mg N=30 N=104 N=154 N=164 N=117 N=124 Durability of Response, n (%)  SDAI ≤11 Wk12 OS 13 (43.3) 48 (46.2) 59 (38.3) 69 (42.1) 31 (26.5) 46 (37.1) Wk24 OS 18 (60.0) 59 (56.7) 87 (56.5) 106 (64.6) 40 (34.2) 56 (45.2) Wk52 OS 23 (76.7) 74 (71.2) Wk48 LTE 23 (76.7) 77 (74.0) 98 (63.6) 106 (64.6) 54 (46.2) 62 (50.0) Wk96 LTE 25 (83.3) 73 (70.2) 86 (55.8) 92 (56.1) 54 (46.2) 62 (50.0)  HAQ-DI imp≥0.22 Wk12 OS 28 (93.3) 80 (76.9) 118 (76.6) 118 (72.0) 85 (72.6) 97 (78.2) Wk24 OS 27 (90.0) 85 (81.7) 121 (78.6) 121 (73.8) 88 (75.2) 92 (74.2) Wk52 OS 24 (80.0) 86 (82.7) Wk48 LTE 25 (83.3) 77 (74.0) 113 (73.4) 115 (70.1) 75 (64.1) 80 (64.5) Wk96 LTE 26 (86.7) 80 (76.9) 98 (63.6) 105 (64.0) 58 (49.6) 79 (63.7) Maintenance of Response at 96 wks, % (n/N')  SDAI ≤11 R 82.6 (19/23) 81.1 (60/74) 70.9 (61/86) 66.7 (68/102) 77.5 (31/40) 77.8 (42/54) NR 85.7 (6/7) 43.3 (13/30) 36.9 (24/65) 36.2 (21/58) 27.8 (20/72) 27.7 (18/65)  HAQ-DI imp≥0.22 R 87.5 (21/24) 84.9 (73/86) 72.7 (88/121) 71.9 (87/121) 56.8 (50/88) 71.7 (66/92) NR 83.3 (5/6) 38.9 (7/18) 30.3 (10/33) 39.0 (16/41) 27.6 (8/29) 40.6 (13/32) Data were analysed using nonresponder imputation without considering rescue status in LTE. N = number of mITT pts; N' = number of responders (R) or nonresponders (NR) at entry into LTE; n = number of pts in the specific category. Conclusions These data provide further evidence of the effectiveness of bari treatment in achievement of meaningful clinical control of disease activity long term. References Fleischmann R et al. Arthritis Rheumatol 2016. Taylor P et al. Arthritis Rheumatol 2015;67(Suppl10). Dougados M et al. Ann Rheum Dis 2017. Genovese MC et al. N Eng J Med 2016. Disclosure of Interest J. Smolen Grant/research support from: Abbvie, Janssen, Eli Lilly and Company, MSD, Pfizer, Roche, Consultant for: Abbvie, Amgen, Astra-Zeneca, Astro, BMS, Celgene, Celltrion, Chugai, Gilead, Glaxo, ILTOO, Janssen, Eli Lilly and Company, Medimmune, MSD, Novartis-Sandoz, Pfizer, Roche, Samsung, Sanofi, UCB, Speakers bureau: Abbvie, Amgen, Astra-Zeneca, Astro, BMS, Celgene, Celltrion, Chugai, Gilead, Glaxo, ILTOO, Janssen, Eli Lilly and Company, Medimmune, MSD, Novartis-Sandoz, Pfizer, Roche, Samsung, Sanofi, UCB, Z. Li: None declared, R. Klar Employee of: Quintiles IMS Holdings, Inc., L. Xie Employee of: Eli Lilly and Company, D. Walker Employee of: Eli Lilly and Company, A. Ghizdavescu Employee of: Eli Lilly and Company, R. Ortmann Employee of: Eli Lilly and Company, M. Dougados Grant/research support from: Abbvie, Pfizer, Eli Lilly and Company, Novartis, UCB, Merck, Roche, BMS, Consultant for: Abbvie, Pfizer, Eli Lilly and Company, Novartis, UCB, Merck, Roche, BMS