Economic Evaluation of Timely Versus Delayed Use of Tumor Necrosis Factor Inhibitors for Treatment of Psoriatic Arthritis in the US

INTRODUCTION: The present study aimed to evaluate clinical outcomes and costs associated with timely versus delayed use of tumor necrosis factor inhibitors (TNFis) among patients with moderately to severely active psoriatic arthritis (PsA) with and without moderate/severe psoriasis (Ps) from a US payer’s perspective. METHODS: An economic model evaluated PsA patients initially treated with a TNFi (timely TNFi use) or apremilast (delayed TNFi use). Patients without joint (American College of Rheumatology 20%, [ACR20]) improvement either switched TNFis or initiated one. ACR20 responses were evaluated for all patients and skin responses by Psoriasis Area Severity Index 75% (PASI75) for those with concomitant PsA and Ps. Published randomized controlled trials and publicly available databases provided model inputs. Effectiveness measures included 1-year responses and number needed to treat (NNT). Direct costs, costs per responder, and incremental costs per responder were calculated. RESULTS: After 1 year, timely TNFi-treated patients had higher ACR20 responses (70.4% vs. 59.6%) and lower NNTs (1.42 vs. 1.68) compared with delayed use. Among PsA + Ps patients, timely TNFi use was associated with higher ACR20 + PASI75 responses (41.0% vs. 30.0%) and lower NNTs (2.44 vs. 3.33). Cost per ACR20 responder was higher ($56,492 vs. $52,835) among PsA patients without Ps; with concomitant Ps, cost per ACR20 + PASI75 responder was lower for timely TNFi use ($100,954 vs. $111,686). Incremental costs per responder for timely versus delayed TNFi were $76,823 in PsA and $71,791 in PsA and Ps. CONCLUSION: Timely use of TNFis is a cost-effective strategy for the management of PsA based on improvements in both joint and/or skin disease. FUNDING: AbbVie Inc.