OBJECTIVES: To assess the cost-effectiveness of mirabegron (50 mg) versus oxybutynin (10 mg) and tolterodine extended release (ER [4 mg]) in patients with overactive bladder (OAB) treated in the Argentinean healthcare system.

METHODS: Cost-effectiveness was assessed over a 5-year time horizon using a Markov model that characterizes the course of disease over time. Model health states were based on disease severity levels, and therapeutic management and complications in hypothetical cohorts of patients with OAB were tracked over one-month cycles. Key model outcomes included costs, quality-adjusted life-years (QALYs), micturition state improvement (MSI), and incontinence state improvement (ISI). Transition probabilities were estimated from a mirabegron trial and a mixed treatment comparison study. Other inputs such as resource use and costs, including costs of anticholinergic burden, comorbidity treatment, drug acquisition, and physician visits, were obtained from published literature and expert opinion. All costs are reported in 2019 US dollars (USD). Deterministic and probabilistic sensitivity analyses were performed.

RESULTS: Mirabegron conferred greater improvement in terms of micturition, incontinence and QALYs than its comparators, oxybutynin and tolterodine ER, although it was associated with higher acquisition costs. The projected QALY gain for mirabegron was similar compared to both tolterodine ER and oxybutynin (0.022 and 0.020). Mirabegron had an incremental cost effectiveness ratio (ICER) of $3,953 per MSI, $4,789 per ISI and $23,522 per QALY versus tolterodine ER and an ICER of $2,699 per MSI, $3,188 per ISI and $17,313 per QALY versus oxybutynin. Probabilistic sensitivity analyses showed that mirabegron was cost effective in 100% of simulations considering a willingness-to-pay (WTP) of 3x per capita GDP of Argentina ($23,995 USD 2019).

CONCLUSIONS: Compared to the most commonly used antimuscarinics in Argentina, mirabegron is cost-effective at a WTP of 3x per-capita GDP per outcome of improvement for the treatment of OAB in the public healthcare system of Argentina.