Akebia Therapeutics and US Renal Care (USRC) have announced the decision by USRC Kidney Research to stop the Vafseo Outcomes In Center Experience—VOICE—trial following a planned interim analysis.
The trial is investigating the safety of three times weekly oral vadadustat (Vafseo) for the treatment of anaemia in haemodialysis patients.
The primary investigator made the decision to stop the study after a recommendation from the Independent Data Monitoring Committee and Trial Steering Committee based on the prespecified stopping criteria and supported by findings of significantly improved safety outcomes in patients treated with vadadustat versus an erythropoiesis-stimulating agent (ESA).
“The VOICE trial was rigorously and pragmatically designed to test the hypothesis that there are clinically important areas of differentiation between Vafseo and ESAs,” said Geoffrey A Block, associate chief medical officer and senior vice president, clinical research & medical affairs for USRC. “Importantly, based on the interim data, we observed that Vafseo resulted in a statistically significant and clinically meaningful reduction in the primary composite endpoint of all-cause mortality and hospitalisation, with the result driven by a reduction in hospitalisation. We are eager to share data that we believe shows substantial clinical benefit with clinicians and dialysis industry colleagues, and expect to submit the VOICE trial results to an upcoming scientific meeting. We are indebted to the thousands of patient volunteers who have participated in this trial, to our team of dedicated Investigators, to the extraordinary work of the USRC Kidney Research team, and to the dedicated staff at all of our participating facilities who bring innovation directly to patient care.”
The VOICE trial enrolled 2,116 patients and was designed as a randomised, open-label, active controlled, non-inferiority trial sponsored by USRC to measure the safety of Vafseo administered three times weekly versus standard-of-care ESA using a hierarchical composite endpoint of mortality and hospitalisation rates.
Results of the planned interim analysis as of 1 June 2026, the data cutoff date, demonstrated that the trial met the predefined stopping criteria with a win odds of 1.16 (95% confidence interval [CI] 1.06, 1.28, p=0.0016), establishing non-inferiority and superiority of the primary composite endpoint.
The results further demonstrated a statistically significant decrease in hospitalisations with Vafseo versus ESA (1.11 versus 1.23 hospitalisations per patient year, incidence rate ratio of 0.90 (95% CI, 0.824, 0.988). There was no statistically significant difference between mortality rates with Vafseo versus ESA (8.77% versus 8.78% per 100 patient-years, incidence rate ratio of 1.00 (95% CI 0.718, 1.391).
“It was striking to see results in the VOICE trial, where we used vadadustat three times weekly during haemodialysis, that were nearly identical to those reported in a post-hoc analysis of the phase 3 INNO2VATE programme, where vadadustat was dosed daily at home,” said Glenn M Chertow (Stanford University School of Medicine, Stanford, USA) and member of the executive steering committee for the VOICE trial. “The data analysed in the VOICE trial confirms the observation that vadadustat, when compared to standard-of-care erythropoiesis stimulating agents, reduces the composite endpoint of death or hospitalisation in patients receiving dialysis with CKD-related anaemia.”
In March 2024, Vafseo was approved by the US Food and Drug Administration (FDA) for the treatment of anaemia due to chronic kidney disease in adults who have been receiving dialysis for at least three months, and it has been available in the USA since January 2025. Vafseo is approved for once-daily administration.
