Results from an 11-year follow-up of studies on the use of tolvaptan to treat autosomal dominant polycystic kidney disease showed a slowing in the decline of kidney function in patients at early and later stages of chronic kidney disease.
The findings, appearing in an upcoming issue of the Clinical Journal of the American Society of Nephrology, “suggest that tolvaptan might delay the need for dialysis or kidney transplantation, provided that its effect on kidney function decline is sustained and cumulative over time,” according to a press release on the study from the American Society of Nephrology. The hormone vasopressin promotes the progression of autosomal dominant polycystic kidney disease (ADPKD), the fourth leading cause of ESRD.
The Mayo Clinic researchers, led by Vincente Torres, MD, PhD, from the division of nephrology and hypertension, reviewed data from 97 patients with ADPKD enrolled in the 3-year Tolvaptan Efficacy and Safety in Management of ADPKD and its Outcomes (TEMPO) 3:4 clinical trial and the 1-year Replicating Evidence of Preserved Renal Function: An Investigation of Tolvaptan Safety and Efficacy in ADPKD trial (REPRISE). Because all patients participating in the clinical trials were given the opportunity of continuing tolvaptan in an open-label extension study, investigators gathered information on the efficacy of tolvaptan during an 11-year period. Kidney function was measured as eGFR.
Investigators found patients treated with tolvaptan had lower eGFR slopes compared with controls (-1.97 vs. -3.50 ml/min per 1.73 m2 per year) and a lower risk of a 33% reduction in eGFR from baseline. Also, the annualized eGFR slopes of patients treated with tolvaptan did not change with the duration of follow-up, according to the press release. The team also compared the eGFR values observed at the last follow-up in the tolvaptan treated patients to the anticipated last follow-up eGFR values.
“The results of the study suggest that the effect of tolvaptan on eGFR in patients with ADPKD is sustained, cumulative and consistent with potentially delaying the need of kidney replacement,” Torres said in the release.
s: Torres is a member of the steering committees for the TEMPO and REPRISE clinical trials, has received research support from Otsuka Pharmaceutical and is a consultant for Vertex, Sanofi-Genzyme and Palladio. Czerwiec is an employee of Otsuka Pharmaceuticals. All other authors reported no relevant financial disclosures.