POS0708 EVALUATING THE HYPERSENSITIVITY PROFILE OF ANIFROLUMAB AND THE NEED FOR PREINFUSION PROPHYLACTIC TREATMENT IN PATIENTS WITH SLE

Background Anifrolumab, a human monoclonal antibody (mAb), is approved in Canada, Japan, and the United States for treatment of patients with systemic lupus erythematosus (SLE) based on results from phase 2b MUSE 3 TULIP-1/-2 trials. 1–3 Anaphylactic reactions (ARs), hypersensitivity (HSRs), infusion-related (IRRs) are risks mAb infusions, so physicians prescribing anifrolumab may wish to understand profile whether prophylactic pretreatments required mitigate HSR/IRRs. Objectives To evaluate need pretreatment. Methods Pooled data were analyzed moderate severe SLE despite standard therapy who received intravenous infusions (every 4 weeks, 48 weeks) or placebo randomized, 52-week ( NCT01438489 ), 1 TULIP-1 NCT02446912 2 TULIP-2 NCT02446899 ) An AR (analyzed 150/300/1000 mg groups) was defined as acute illness onset within minutes several hours infusion involvement skin and/or mucosal tissue, respiratory compromise, reduced blood pressure, persistent gastrointestinal symptoms. HSRs IRRs 300 group (as this dose) group. HSR tissue during (not meeting definition); IRR any other reaction occurring during/within 24 infusion. Patients did not receive pretreatment unless they had experienced previous IRR/HSR program. Pretreatment assumed if patient antihistamine, corticosteroid, non-steroidal anti-inflammatory drug, dopamine antagonist day before/on Results Of (n=459), 1000 (n=105), (n=466), none ARs; 150 (n=93) an AR. occurred 3% (n=12) mg-treated (of whom history HSRs) vs 1% (n=3) 9% (n=43) anifrolumab-treated 7% (n=33) All mild/moderate intensity. There no discontinuations due group, while there (HSR: n=1; IRR: n=1). In groups, more HSR/IRRs initial (1–6) later (Figure 1). median (median absolute deviation) time first 30.5 (29.5) days 27.0 (26.0) days, respectively. 12 ≥1 HSR, subsequent pretreatment, after use 43 IRR, dosage remained unchanged. Conclusion Following infusion, ARs uncommon, few (3%) HSRs. dose mild moderate, early treatment, lead discontinuation, only rarely Our support safe manageable anifrolumab. References [1]Furie R, et al. Arthritis Rheumatol . 2017;69:376–86. [2]Furie Lancet 2019;1:e208–19. [3]Morand E, N Engl J Med 2020;382:211–21. Acknowledgements Writing assistance provided by Rosie Butler, PhD, JK Associates Inc., part Fishawack Health. This study sponsored AstraZeneca. Disclosure Interests Kenneth C Kalunian Consultant of: Aurinia, Equillium, Kezar, BMS, Chemocentryx, Eli Lilly, Biogen, Roche/Genentech, Grant/research from: Horizon, UCB, Yoshiya Tanaka Speakers bureau: Gilead, Abbvie, Behringer-Ingelheim, Mitsubishi-Tanabe, Chugai, Amgen, YL Biologics, Eisai, Astellas, Bristol-Myers, Astra-Zeneca, Daiichi-Sankyo, Taisho, Ayumi, Sanofi, GSK, Asahi-Kasei, Takeda, Corrona, Kowa, Ihor Hupka Employee AstraZeneca, Lijin (Jinny) Zhang Shareholder Manish Shroff Shanti Werther Gabriel Abreu AstraZeneca AB, Catharina Lindholm Raj Tummala