OBJECTIVES : To compare cost-effectiveness of sequential treatments for patients with psoriatic arthritis (PsA) from US societal perspective.

METHODS : A discretely integrated condition event simulation model was constructed to examine cost-effectiveness of sequential biologic disease-modifying (bDMARD) drugs in PsA. Three different sequences of biologics were compared to conventional DMARDs (cDMARDs) over 20 years. The sequences comprised six bDMARDs and included (1) current practice (adalimumab → etanercept → ustekinumab → secukinumab 150mg → secukinumab 300mg → apremilast); (2) a sequence of bDMARDs with different mechanisms of action (MOA switchers; adalimumab → secukinumab 150mg → secukinumab 300mg → ustekinumab → apremilast →etanercept); and (3) an optimal sequence based on highest quality-adjusted life years (QALYs) produced using a single biologic therapy over five years. Efficacy inputs (20% improvement in American College of Rheumatology criteria, Health Assessment Questionnaire, Psoriasis Area and Severity Index) were obtained from network meta-analyses. bDMARD costs were based on wholesale acquisition costs with 30% rebate. Cost (2017 US$) and outcomes were discounted at 3%/year, and $150,000/QALY threshold value was implemented. Simulations were run for 1,000 patients.

RESULTS : The single biologic therapies produced the following QALYs over five 5 years to produce the optimal sequence: etanercept (4.38) → infliximab (4.36) → golimumab (4.33) → adalimumab (4.30) → secukinumab 150mg (4.30) → secukinumab 300mg (4.30). The optimal sequence compared to the current practice and MOA switchers sequences was $5,801 and $8,490 less expensive and produced 0.22 and 0.23 more QALYs, respectively. The three sequences were determined to be cost-effective vs cDMARDs, with an incremental cost-effectiveness ratio of $122,708, $135,616, and $137,277 per QALY for the optimal, current practice, and MOA switchers sequences, respectively. Probabilistic sensitivity analysis confirmed the results of bDMARDs sequences vs cDMARDs.

CONCLUSIONS : The optimal treatment sequence starting with etanercept was more cost-effective than other sequences, and bDMARDs were more cost-effective than cDMARDs.