E067 Bimekizumab maintained efficacy responses through 52 weeks in biologic disease-modifying antirheumatic drugnaïve patients with psoriatic arthritis who were responders at week 16: results from BE OPTIMAL, a phase 3, activereference study

Abstract Background/Aims Given the chronic nature of psoriatic arthritis (PsA), sustaining high levels of disease control with treatment is important. Assessing maintenance of response in patients that achieve treatment targets is of interest as loss of response can occur with long-term therapy. Bimekizumab (BKZ), a monoclonal IgG1 antibody that selectively inhibits interleukin (IL)-17F in addition to IL-17A, has demonstrated rapid, clinically meaningful joint and skin efficacy responses at Week (Wk) 16 versus placebo (PBO) in patients with PsA; responses were sustained to Wk52. We report the maintenance of response in joint and skin efficacy outcomes to 52 wks in BKZ-treated patients with PsA who responded at Wk16. Methods BE OPTIMAL (NCT03895203), which included a 16-wk double-blind, PBO-controlled period and a 36-wk active treatment-blind period, assessed BKZ in biologic disease-modifying antirheumatic drug (DMARD)-naïve patients with active PsA. Patients were randomised 3:2:1 to subcutaneous BKZ 160mg every 4 wks (Q4W), PBO or reference (adalimumab 40mg Q2W). At Wk16, PBO patients switched to BKZ 160mg Q4W. Maintenance of response is reported as the percentage of BKZ-treated patients who achieved response at Wk16 and maintained at Wk52. Data are reported for patients randomised to BKZ 160mg Q4W at baseline. Endpoints include American College of Rheumatology (ACR)20/50/70, Psoriasis Area and Severity Index (PASI)75/90/100, minimal/very low disease activity (MDA/VLDA) and Disease Activity Index for PSoriatic Arthritis (DAPSA) remission or low disease activity (REM+LDA; ≤14) and remission (REM; ≤4) responses. Wk16 responders are reported using nonresponder imputation (NRI); maintenance of response to Wk52 is reported using NRI and observed case (OC). Treatment-emergent adverse events (TEAEs) to Wk52 are reported for patients who received ≥1 dose of BKZ, including patients randomised to PBO at baseline. Results At baseline, 431 patients were randomised to BKZ 160mg Q4W; 217/431 (50.3%) had psoriasis affecting ≥3% body surface area (BSA). 414/431 (96.1%) completed Wk16; 388 (90.0%) completed Wk52. Most patients who achieved response at Wk16 maintained at Wk52 across a range of joint and skin outcomes. At Wk16, 268 (62.2%)/189 (43.9%)/105 (24.4%) patients achieved ACR20/50/70; responses were maintained at Wk52 by 88.4%/86.8%/82.9% (NRI); 92.9%/91.1%/87.9% (OC). Of 217 patients with psoriasis affecting ≥3% BSA at baseline, 168 (77.4%)/133 (61.3%)/103 (47.5%) achieved PASI75/90/100 at Wk16. Most patients maintained response at Wk52: 88.1%/82.7%/79.6% (NRI); 98.7%/94.0%/89.1% (OC). The same pattern was observed for composite measures of efficacy. 194(45.0%) patients achieved MDA at Wk16; 85.6% (NRI)/90.7% (OC) maintained response at Wk52. At Wk16, 205 (47.6%)/47 (10.9%) achieved DAPSA REM+LDA/DAPSA REM; 85.9%/68.1% maintained response at Wk52. To Wk52, 555/702 (79.1%) BKZ-treated patients reported ≥1 TEAE; 46 (6.6%) reported serious TEAEs. Conclusion With BKZ treatment, most Wk16 responders maintained robust efficacy responses to Wk52 across joint, skin and composite efficacy outcomes. Safety profile of BKZ was consistent with previous reports. Disclosure W.R. Tillett: Consultancies; AbbVie, Amgen, Celgene, Eli Lilly, GSK, Janssen, MSD, Novartis, Ovo Pharma, Pfizer and UCB Pharma. Honoraria; AbbVie, Amgen, Celgene, Eli Lilly, GSK, Janssen, MSD, Novartis, Ovo Pharma, Pfizer and UCB Pharma. Grants/research support; AbbVie, Amgen, Celgene, Eli Lilly, GSK, Janssen, MSD, Novartis, Ovo Pharma, Pfizer, UCB Pharma. Other; Speaking fees from AbbVie, Amgen, Celgene, Eli Lilly, GSK, Janssen, MSD, Novartis, Ovo Pharma, Pfizer and UCB Pharma. J.F. Merola: Consultancies; AbbVie, Amgen, Biogen, BMS, Dermavant, Eli Lilly, Janssen, LEO Pharma, Novartis, Pfizer, Regeneron, Sanofi, Sun Pharma and UCB Pharma. Other; Investigator for AbbVie, Amgen, Biogen, BMS, Dermavant, Eli Lilly, Janssen, LEO Pharma, Novartis, Pfizer, Regeneron, Sanofi, Sun Pharma and UCB Pharma. Y. Tanaka: Honoraria; AbbVie, AstraZeneca, BMS, Boehringer Ingelheim, Chugai, Eisai, Eli Lilly, Gilead, GSK, Pfizer, Taiho and Taisho. Grants/research support; Chugai, Mitsubishi-Tanabe and Taisho. Other; Speaking fees from AbbVie, AstraZeneca, BMS, Boehringer Ingelheim, Chugai, Eisai, Eli Lilly, Gilead, GSK, Pfizer, Taiho and Taisho. E.G. Favalli: Consultancies; AbbVie, BMS, Celltrion, Eli Lilly, Galapagos, Janssen, MSD, Novartis, Pfizer and UCB Pharma. Other; Speaking fees from AbbVie, BMS, Celltrion, Eli Lilly, Galapagos, Janssen, MSD, Novartis, Pfizer and UCB Pharma. D. McGonagle: Consultancies; AbbVie, Celgene, Janssen, Merck, Novartis, Pfizer and UCB Pharma. Honoraria; AbbVie, Celgene, Janssen, Merck, Novartis, Pfizer and UCB Pharma. Member of speakers’ bureau; AbbVie, Celgene, Janssen, Merck, Novartis, Pfizer and UCB Pharma. Grants/research support; AbbVie, Celgene, Janssen, Merck, Novartis and Pfizer. J.A. Walsh: Consultancies; AbbVie, Amgen, Eli Lilly, Janssen, Merck, Novartis, Pfizer and UCB Pharma. Grants/research support; AbbVie, Amgen, Eli Lilly, Janssen, Merck, Novartis, Pfizer and UCB Pharma. D. Thaçi: Consultancies; AbbVie, Almirall, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, Celltrion, Eli Lilly, Galapagos, Galderma, Janssen-Cilag, Kyowa Kirin, LEO Pharma, Novartis, Pfizer, Regeneron, Samsung, Sandoz, Sanofi, Target-Solution and UCB Pharma. Grants/research support; AbbVie, LEO Pharma and Novartis. Other; Investigator for AbbVie, Almirall, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, Celltrion, Eli Lilly, Galapagos, Galderma, Janssen-Cilag, Kyowa Kirin, LEO Pharma, Novartis, Pfizer, Regeneron, Samsung, Sandoz, Sanofi, Target-Solution and UCB Pharma. B. Ink: Shareholder/stock ownership; AbbVie, GSK and UCB Pharma. Other; Employee of UCB Pharma. R. Bajracharya: Shareholder/stock ownership; UCB Pharma. Other; Employee of UCB Pharma. V. Taieb: Shareholder/stock ownership; UCB Pharma. Other; Employee of UCB Pharma. C.T. Ritchlin: Consultancies; AbbVie, Amgen, Eli Lilly, Gilead, Janssen, Novartis, Pfizer and UCB Pharma. Grants/research support; AbbVie.