Background:Rotator cuff tendinopathy (RC TP) is a multifactorial condition and one of the most common causes of musculoskeletal burden. Current standard of care (SoC) is limited to pain relief with NSAIDs and physiotherapy. Recent evidence indicates that IL-17A-expressing tendon-resident immune cells are present in human overuse tendinopathy, and IL-17A levels are increased in early human tendinopathic tissue samples [1, 2]. Secukinumab (SEC) is a fully human, monoclonal antibody that binds to and neutralises IL-17A.Objectives:To evaluate the efficacy and safety of SEC in patients with active overuse RC TP refractory to oral NSAIDs/acetaminophen, physiotherapy or corticosteroid injections.Methods:96 patients with symptomatic RC TP with no or Results:Clinically relevant improvement in both SEC and PBO groups on top of SoC treatment was observed, with no statistically significant difference demonstrated in the full study population on physical symptoms and function (Table 1). Similar results were observed in the secondary endpoints with marked improvement in both groups over time. Exploratory post-hoc analyses in a subpopulation of 39% of the study subjects with non-acute, moderate to severe disease, SEC provided significant and clinically relevant improvements vs PBO through Week 24 in total WORC score (overall treatment difference: 19.2, p Conclusion:Although SEC did not demonstrate a significant benefit vs PBO in the overall patient population with active overuse RC TP, SEC did provide benefit in the subpopulation with non-acute, moderate to severe disease. Larger clinical trials of SEC in this area are warranted.References:[1]Millar NL, et al. Sci Rep. 2016;6:27149.[2]Millar NL, et al. Nat Rev Rheumatol.2017;13:110-122.Table 1.Change from baseline in the SEC versus PBO groups in WORC index and pain (VAS)VisitSEC 300 mgPBOp-valueTotal treated population N=96WORC Index percentage score (0 worst -100 best)aDay 2922.3519.490.45Day 9937.0037.770.87Day 16943.4140.970.64Pain (VAS, 0 best - 100 worst)bDay 29−26.04−23.130.57Day 99−46.11−40.560.28Day 169−52.23−50.740.78Post-hoc population* N=37WORC Index percentage score (0 worst - 100 best)cDay 2930.0910.840.002Day 9948.2631.830.048Day 16955.9835.240.028Pain (VAS, 0 best - 100 worst)dDay 29−29.20−14.850.125Day 99−51.48−35.370.045Day 169−57.01−46.640.217aDay 1: SEC 42.47, PBO 40.47; bSEC 67.04, PBO 64.85; cSEC 35.93, PBO 32.90, dSEC 71.72, PBO 67.58. Day 1 values are given as absolute values to describe baseline WORC/Pain status*Post-hoc subpopulation: Baseline: (Disease duration 2-6 months) AND (WORC ≤40 OR Tear Thickness (Bauer) ≥1 OR Sein ≥2)PBO, placebo; SEC, secukinumab; SoC, standard of care; WORC, Western Ontario Rotator Cuff Index; VAS, visual analogue scaleFigure 1.Post-hoc analysis of function (WORC) in the treatment groups in non-acute, moderate to severe subpopulationSECSE, standard error; SEC, secukinumab; WORC, Western Ontario Rotator Cuff IndexDisclosure of Interests:Neal L Millar Grant/research support from: Honoraria or research funding from Novartis and Stryker, Iain McInnes Speakers bureau: AbbVie, Amgen, Bristol-Myers Squibb, Celgene, Janssen, Lilly, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb, Celgene, Janssen, Lilly, Novartis, Pfizer, and UCB, Grant/research support from: AbbVie, Amgen, Bristol-Myers Squibb, Celgene, Janssen, Lilly, Novartis, Pfizer, and UCB, Linda Mindeholm Employee of: Employee of Novartis, Abdelkader Seroutou Employee of: Employee of Novartis, Jens Praestgaard Employee of: Employee of Novartis, Ursula Schramm Employee of: Employee of Novartis, Rafael Levitch Employee of: Employee of Novartis, Eckhard Weber Employee of: Employee of Novartis, Didier Laurent Employee of: Employee of Novartis, Jeffrey Rosen Consultant of: Research advisor for Novartis, Georg Schett Speakers bureau: Received speakers honoraria from Abbvie, Amgen, BMS, Eli Lilly, Gilead, Janssen, Novartis, UCB, Ronenn Roubenoff Employee of: Employee of Novartis, Matthias Schieker Employee of: Employee of Novartis.