Background: In the TEMPO (Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and Its Outcomes) trial, tolvaptan significantly reduced expansion of kidney volume and loss of kidney function.
Objective: To determine how the benefits of tolvaptan seen in TEMPO may relate to longer-term health outcomes, such as progression to end-stage renal disease (ESRD) and death, and cost-effectiveness.
Design: A decision-analytic model.
Data sources: Published literature from 1993 to 2012.
Target population: Persons with early autosomal dominant polycystic kidney disease.
Time horizon: Lifetime.
Intervention: Patients received tolvaptan therapy until death, development of ESRD, or liver complications or no tolvaptan therapy.
Outcome measures: Median age at ESRD onset, life expectancy, discounted quality-adjusted life-years and lifetime costs (in 2010 U.S. dollars), and incremental cost-effectiveness ratios.
Results of base-case analysis: Tolvaptan prolonged the median age at ESRD onset by 6.5 years and increased life expectancy by 2.6 years. At $5760 per month, tolvaptan cost $744 100 per quality-adjusted life-year gained compared with standard care.
Results of sensitivity analysis: For patients with autosomal dominant polycystic kidney disease that progressed more slowly, the cost per quality-adjusted life-year gained was even greater for tolvaptan.
Limitation: Although TEMPO followed patients for 3 years, the main analysis assumed that clinical benefits persisted over patients' lifetimes.
Conclusion: Assuming that the benefits of tolvaptan persist in the longer term, the drug may slow progression to ESRD and reduce mortality rates. However, barring an approximately 95% reduction in price, cost-effectiveness does not compare favorably with many other commonly accepted medical interventions.
Primary funding source: National Institutes of Health and Agency for Healthcare Research and Quality.