Aims: To assess from a US payer perspective the relative cost-effectiveness of the catechol-O-methyltransferase inhibitors opicapone and entacapone when used adjunctively to levodopa/carbidopa (LD/CD) in patients with Parkinson''s disease (PD), based on the drugs'' effects to reduce absolute OFF-time hours in PD patients.
Materials and methods: A Markov model was created to estimate cost-effectiveness of adjunctive opicapone treatment compared with adjunctive entacapone treatment in a synthetic cohort of 1,000 patients with PD taking LD/CD. Clinical inputs were derived from clinical trials, published literature, and expert opinion. Cost data (in 2018 US dollars) were obtained from the Centers for Medicare & Medicaid Services, the Kaiser Family Foundation, and Analy$ource. Cost-effectiveness outcomes included incremental cost per OFF-time hours avoided, cost per life year gained, and cost per quality-adjusted life year (QALY) gained. Outcomes were projected over a 25-year lifetime horizon and discounted at 3% annually.
Results: Opicapone treatment was associated with an average of 1,187 fewer OFF-time hours per patient and an increase of 0.07 QALYs compared with entacapone. Total lifetime costs for opicapone were $3,100 higher than entacapone, resulting in an incremental cost-effectiveness ratio of $46,900 per QALY. One-way sensitivity analyses showed the model was most sensitive to mean OFF-time hours associated with opicapone and entacapone. Probabilistic sensitivity analysis suggested a 60-65% probability that opicapone was cost-effective relative to entacapone at any willingness-to-pay threshold ≥$5,000.
Limitations: There exists a single head-to-head clinical trial comparing the effectiveness of opicapone with entacapone, thus the clinical inputs regarding relative treatment effect of the drugs to reduce OFF-time hours in PD patients receiving LD/CD were derived from that single non-inferiority trial.
Conclusions: Add-on treatment with opicapone in PD patients receiving LD/CD appeared to be cost-effective compared with entacapone.
Keywords: COMT inhibitors; I11; I13; OFF-time; Parkinson’s disease; cost effectiveness; entacapone; opicapone.