APREMILAST REDUCES INFLAMMATION AS MEASURED BY MRI, CLINICAL OUTCOMES, AND PATIENT-REPORTED OUTCOMES IN PATIENTS WITH PSORIATIC ARTHRITIS: RESULTS FROM THE PHASE 4 MOSAIC STUDY

Background: Psoriatic arthritis (PsA) is characterized by inflammatory arthritis, enthesitis, dactylitis, and spondylitis. Apremilast is an oral immunomodulating phosphodiesterase-4 inhibitor approved for treatment of PsA. Results from the MOSAIC study demonstrated that treatment with apremilast in patients with active PsA led to significant improvements in objective MRI indices of inflammation of the hand as assessed by the PsA MRI Score (PsAMRIS) [1] as well as significant reduction in total peripheral inflammation, including significant improvement in peripheral joint inflammation and enthesitis, as assessed by whole-body MRI (WB-MRI) [2]. Objectives: To evaluate the efficacy of apremilast on MRI endpoints, clinical outcomes, and patient reported outcomes (PROs) in patients with PsA treated with apremilast 30 mg BID in the MOSAIC study. Methods: MOSAIC (NCT03783026) was a phase 4, multicenter, single-arm, open-label study in patients with active PsA (≥3 months but ≤5 years since diagnosis, meeting CASPAR criteria) evaluating apremilast as monotherapy or in combination with stable methotrexate. Patients were treated with apremilast for 48 weeks and had contrast-enhanced MRI of the hand and WB-MRI performed at baseline, Week 24, and Week 48. All images were read and adjudicated by 2 experienced readers blinded to clinical information and acquisition time. MRI endpoints included change from baseline in the composite and total inflammation scores of hand bone marrow edema, synovitis, and tenosynovitis in fingers 2–5 as assessed by PsAMRIS at Weeks 24 and 48, as well as total peripheral inflammation index as assessed by WB-MRI. Clinical outcomes included change from baseline to Weeks 24 and 48 in swollen joint count (SJC), tender joint count (TJC), Clinical Disease Activity Index for Psoriatic Arthritis (cDAPSA) score, and evaluator’s global assessment of disease activity. PROs included change from baseline in Psoriatic Arthritis Impact of Disease 12 items (PsAID-12), patient assessed disease activity and pain and Health Assessment Questionnaire-Disability Index (HAQ-DI score). Results: A total of 122 patients were enrolled and received apremilast. Mean age was 47 years and 55% were women. Disease duration was limited (mean 1.9 years). At baseline, mean (SD) for MRI endpoints were composite inflammation 18.5 (17.8), total inflammation 25.8 (24.2), and peripheral inflammation 28.8 (22.5); mean (SD) SJC was 8.0 (7.2), TJC 14.6 (11.3), cDAPSA 31.9 (16.5), and evaluator’s global assessment of disease activity 5.2 (1.5); mean (SD) PsAID-12 4.75 (1.87), patient’s global assessment of disease activity 5.6 (1.8), patient’s assessment of pain 5.6 (1.8), and HAQ-DI 1.01 (0.57). Apremilast treatment resulted in significant changes from baseline to Weeks 24 and 48 in the composite inflammation score and total inflammation score by PsAMRIS, and peripheral inflammation index by WB-MRI (Figure 1). Significant reductions were observed with clinical outcomes and PROs at weeks 24 and 48, including SJC, TJC, cDAPSA, evaluator’s global assessment of disease activity, PsAID-12, patient’s global assessment of disease activity, patient’s assessment of pain, and HAQ-DI (Figure 2). Conclusion: Patients with PsA treated with apremilast had significant improvements in MRI endpoints, clinical outcomes, and PROs at Weeks 24 and 48, confirming the effect of apremilast on clinical and inflammatory manifestations of PsA. These results offer important insights on the effect of apremilast in PsA and highlight the value of using MRI of the hand and whole body as measures of inflammatory disease activity and change following treatment. REFERENCES: [1] Østergaard M, et al. Ann Rheum Dis. 2023;82:341-42. [2] Østergaard M, et al. Ann Rheum Dis. 2023;82:2000-01. Figure 1. Improvements in MRI scores of inflammation during apremilast therapy. Figure 2. Improvements in clinical disease activity scores and patient-reported outcomes during apremilast therapy. Acknowledgements: This clinical trial was sponsored by Amgen Inc. Medical writing support was funded by Amgen Inc. and provided by Martha Mutomba (on behalf of Amgen Inc) and Jessica Ma, employee of and stockholder in Amgen Inc. Disclosure of Interests: Philip J. Mease AbbVie, Amgen Inc., Eli Lilly, Janssen, Novartis, Pfizer, and UCB, AbbVie, Acelvrin, Amgen Inc., Bristol Myers Squibb, Eli Lilly, Galapagos, Gilead, Janssen, Novartis, Pfizer, Sun, UCB, Aclaris, Boehringer Ingelheim, GlaxoSmithKline, Moonlake Pharma, Takeda, and Ventyx, AbbVie, Acelvrin, Amgen Inc., Bristol Myers Squibb, Eli Lilly, Galapagos, Gilead, Janssen, Novartis, Pfizer, Sun, and UCB, Walter P Maksymowych AbbVie, BMS, Celgene, Galapagos, Gilead, Janssen, Lilly, Novartis, Pfizer, and UCB, AbbVie, Novartis, Pfizer, and UCB, Mikael Boesen AbbVie, Celgene, Eli Lilly, Image Analysis Group, Novartis, Pfizer, and UCB, AbbVie, Celgene, Eli Lilly, Image Analysis Group, Novartis, Pfizer, and UCB, AbbVie, Celgene, and Novartis, Robert G Lambert Calyx, CARE Arthritis Limited, and Image Analysis Group, Guillermo Valenzuela AbbVie, Amgen Inc., AstraZeneca, BMS, Boehringer Ingelheim, Celgene, Centocor, Eli Lilly, Genentech, Horizon, Janssen, Mallinckrodt, Novartis, Pfizer, Pharmacia, Radius, Regeneron, Sanofi, Takeda, and UCB, AbbVie, Alexion, Amgen Inc., Boehringer Ingelheim, Celgene, Eli Lilly, Esaote, Exagen, Genentech, Gilead, Global Health Living, Horizon, Image Analysis Group, Janssen, Merck, Novartis, Pfizer, Regeneron, Sandoz, Sanofi, and UCB, Mallinckrodt and Novartis, Michael Bubb Amgen Inc., BMS, Eli Lilly, Gilead, GSK, Janssen, Novartis, Pfizer, and UCB, Olga Kubassova: None declared, Frank Behrens Abbvie, Pfizer, Roche, Chugai, UCB, BMS, Amgen, Celgene, MSD, Novartis, Janssen, Lilly, Sanofi, Biogen, Sandoz, GSK, Abbvie, Pfizer, UCB, BMS, Celgene, Amgen, Novartis, Janssen, Lilly, MSD, Sanofi, GSK, Abbvie, Pfizer, Roche, Chugai, Prophylix, Rallybio, BMS, Novartis, Amgen, Janssen, Jyotsna Reddy Amgen Inc, Amgen Inc, Stephen Colgan Amgen Inc, Amgen Inc, Yuri Klyachkin Amgen Inc, Amgen Inc, Cynthia Deignan Amgen Inc, Amgen Inc, Zhenwei Zhou Amgen Inc, Amgen Inc, Mikkel Østergaard Amgen Inc, Amgen Inc DOI: 10.1136/annrheumdis-2024-eular.2405 Keywords: Patient Reported Outcome Measures, Randomized controlled trial, Magnetic Resonance Imaging Citation: , volume 83, supplement 1, year 2024, page 704Session: Psoriatic arthritis (Poster View)

Patient Reported Outcome Measures, Randomized controlled trial, Magnetic Resonance Imaging