Oxybutynin and tolterodine for treatment of neurogenic detrusor overactivity: a pharmacoeconomic evaluation in the Brazilian context

Antimuscarinic agents are the first-line choice for the treatment of neurogenic detrusor overactivity (NDO). The currently available antimuscarinic drugs have been widely studied in patients presenting idiopathic detrusor overactivity; however, investigations evaluating the effects of these drugs on NDO are scant, particularly with regard to cost-effectiveness analyses. A pharmacoeconomic evaluation was performed to compare the costs and effectiveness of oxybutynin and tolterodine in two different formulations, extended (ER) and immediate-release (IR), for the treatment of NDO (based on Brazilian maximal consumer price index). A systematic review of literature was conducted in order to obtain significant clinical and urodynamic data (based on expert opinion), concerning the effects of these drugs in the neurogenic population. Furthermore, a pharmacoeconomic evaluation was performed and costs involved were calculated based on percentage effectiveness obtained for the timeframes of one month and of one year. The best cost-effectiveness ratio (CER) was observed with oxybutynin IR for the urodynamic parameters. In terms of clinical parameters, oxybutynin IR and ER showed the best CER. Based on the key urological parameters analyzed, oxybutynin IR was considered the most cost-effective antimuscarinic agent.