The NOCTURNE Randomized Trial Comparing 2 Tolvaptan Formulations

Introduction Tolvaptan, a treatment for autosomal dominant polycystic kidney disease (ADPKD), inhibits vasopressin V2 receptor signaling, which causes aquaretic adverse events (AAEs). The short-term efficacy and tolerability of a once-daily, modified-release (MR) formulation was assessed relative to the twice-daily, immediate-release (IR) formulation. Methods This Phase 2 multicenter, randomized (1:1:1:1), placebo-controlled, double-blind, placebo-masked, parallel-group study (NCT01451827) compared tolvaptan MR 50 mg once daily or tolvaptan MR 80 mg once daily with tolvaptan IR 60/30 mg daily split dose and placebo over 8 weeks in 177 subjects. The primary endpoint was percent change from baseline in total kidney volume (TKV) at week 3. Other endpoints included tolerability, assessed by adverse events and quality of life (QOL) measures. Results Mean percentage decreases in TKV at week 3 were observed for the pooled group of all (MR+IR) tolvaptan-treated subjects (−2.07%), tolvaptan MR 80 mg (−2.55%), and tolvaptan MR 50 mg (−2.46%) versus placebo (0.09%; P  Conclusion Tolvaptan MR and tolvaptan IR demonstrated similar short-term efficacy, tolerability, and safety, with low impact on multiple measures of QOL. Conclusions regarding long-term efficacy are limited by the short duration of follow-up.