A Cost-Effectiveness Analysis of Onabotulinumtoxin A as First-Line Treatment for Overactive Bladder
Obstetrical and Gynecological Survey
© 2018 Wolters Kluwer Health, Inc. All rights reserved. First-line therapy for overactive bladder (OAB) includes an anticholinergic (ACH) medication and behavioralmodification. There are high rates of discontinuation with ACH because of adverse effects such as dry mouth, dry eyes, and constipation. Although detrusor injection of onabotulinumtoxinA (Botox) is a highly efficacious treatment for OAB, it is not considered a first-line treatment option and is restricted to use when ACH medications fail. The aim of this study was to determine whether Botox is a cost-effective first-line treatment for women with OAB that should be offered, even before prescribing ACH. A cost-effectiveness analysis was performed modeling the following clinical options: no treatment, receptor nonselective ACH, receptor selective ACH, and Botox. To allow Botox reinjection, discontinuation of anticholinergics, and follow-up, the model timeframe was 2 years. Multiple efficacy levels for each treatment option included symptomimprovement by less than 50%, 50%, 75%, and 100%. If efficacy of 50%or greater was not reached with the first Botox injection, a second injection was allowed at 6 months. Complications of Botox and adverse effects of the ACH medication were noted. Up to one medication switch was modeled for adverse effects or lack of efficacy. Crossover from ACH to Botox or vice versa was not allowed, and patients who failed the treatment options were considered to have refractory, untreated OAB. A cost-effectivenessmodel was constructed using data fromthe medical literature. Costs were converted to 2016 US dollars when appropriate. The incremental cost-effectiveness ratio was used to determine cost-effectiveness. "Dominated" strategies (treatment options) were both less effective and more expensive than another strategy. Multiple one-way sensitivity analyses were used to evaluate the robustness of the model. Botox was more expensive than nonselective ACH, but less expensive than selective ACH, in models with and without refractory overactive bladder costs. Of the treatment options, Botox had the highest effectiveness (1.763 quality-adjusted life years) and was more cost-effective in models including and excluding refractory costs ($12,428.75 and $14,437.01, respectively). Botox was more effective and less costly than selective ACH and was the dominant strategy for that comparison pair. Over 2 years, the average time patients used oral medication was 15.6 months for selective ACH and 14.3 months for nonselective ACH, and patients averaged 2.2 Botox injections. Variation of input parameter estimates in sensitivity analyses did change the results. These findings demonstrate that it would be cost-effective to offer Botox as a first-time treatment for overactive bladder instead of offering it after anticholinergic failure, and suggest the current treatment paradigm should be reevaluated.
Shepherd, J., Carter-Brooks, C., & Chermanksy, C. (2018). A Cost-Effectiveness Analysis of Onabotulinumtoxin A as First-Line Treatment for Overactive Bladder. Obstetrical and Gynecological Survey, 73 (11). http://dx.doi.org/10.1097/OGX.0000000000000620