Cost-effectiveness of tolvaptan in autosomal dominant polycystic kidney disease

Tolvaptan in Pediatric Autosomal Dominant Polycystic Kidney Disease: From Here to Where?

Background

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disorder, accounting for approximately 5% of all ESRD cases worldwide. As a vasopressin receptor 2 antagonist, tolvaptan is the FDA-approved therapeutic agent for ADPKD, which is only made available to a limited number of adult patients; however, its efficacy in pediatric patients has not been reported widely.

Summary

Tolvaptan was shown to delay ADPKD progression in the Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and Its Outcomes (TEMPO) 3:4 study, Replicating Evidence of Preserved Renal Function: an Investigation of Tolvaptan Safety and Efficacy in ADPKD (REPRISE) trial, and other clinical studies. In addition to its effects on aquaretic adverse events and alanine aminotransferase elevation, the effect of tolvaptan on ADPKD is clear, sustained, and cumulative. While ADPKD is a progressive disease, the early intervention has been shown to be important and beneficial in hypotheses as well as in trials. The use of tolvaptan in pediatric ADPKD involves the following challenges: patient assessment, quality of life assessment, cost-effectiveness, safety, and tolerability. The ongoing, phase 3b, 2-part study (ClinicalTrials.gov identifier: NCT02964273) on the evaluation of tolvaptan in pediatric ADPKD (patients aged 12-17 years) may help obtain some insights.

Key Messages

This review focuses on the rationality of tolvaptan use in pediatric patients with ADPKD, the associated challenges, and the suggested therapeutic approaches.

Tolvaptan in the treatment of autosomal dominant polycystic kidney disease: patient selection and special considerations

Standard of care therapies for autosomal dominant polycystic kidney disease (ADPKD) may limit morbidity and mortality due to disease-related complications, but they do not delay disease progression. Tolvaptan, a selective vasopressin V2 receptor antagonist, delays the increase in kidney volume (a surrogate marker for disease progression), slows the decline in renal function, and reduces pain in ADPKD patients with relatively preserved renal function. The most common adverse events of tolvaptan are linked to its aquaretic effect, and rare cases of idiosyncratic hepatitis were observed. Additional ongoing studies will determine whether the benefits are sustained over time, whether they can be observed in patients with advanced kidney disease, and whether they can be translated in terms of quality of life and cost/effectiveness parameters. Tolvaptan is currently approved in Europe and several countries throughout the world. In real-life conditions, selection of patients that would be good theoretical candidates to tolvaptan is a key but complex question. Eligibility criteria slightly differ from one country to another, and several models (based on conventional data, genetics, renal volume) were recently proposed to identify patients with evidence or risk of rapid disease progression. Eligible patients will ultimately make the decision to start tolvaptan, after complete information, consideration, and balancing of benefits, adverse events, and risks.