Abstract: FR-PO0096
Reduction of Kidney Manifestations with Tolvaptan Through Six Years of the C-MAJOR Registry
Session Information
- ADPKD and Cystic Kidney Disease - 2
October 23, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Genetic Diseases of the Kidneys
- 1201 Genetic Diseases of the Kidneys: Cystic (Monogenic)
Authors
- McFarlane, Philip, University of Toronto, Toronto, Ontario, Canada
- Bichet, Daniel G., University of Montreal Clinical Research Center, Montreal, Quebec, Canada
- Alam, Ahsan, McGill University Health Centre, Montreal, Quebec, Canada
- Bubolic, Suzy, Otsuka Canada Pharmaceutical Inc, Saint-Laurent, Quebec, Canada
- Laplante, Annick, Otsuka Canada Pharmaceutical Inc, Saint-Laurent, Quebec, Canada
Background
Autosomal dominant polycystic kidney disease (ADPKD) is a hereditary disorder often leading to kidney failure, with a wide range of manifestations. Tolvaptan is efficacious in slowing progression of kidney enlargement and functional decline in ADPKD, however long-term real-world data with tolvaptan are limited. This analysis examined kidney manifestations through 6 years of tolvaptan in people with ADPKD enrolled in the C-MAJOR registry.
Methods
C-MAJOR (NCT02925221) was a Canadian multicenter observational study of adults with ADPKD initiating tolvaptan from 2015-2025. Routine care patient data were collected at baseline and 6-month intervals thereafter. Due to attrition over time, data were analyzed through 72 months from 2015-2023. Urinary tract infections (UTIs), hematuria, nephrolithiasis, albuminuria, and kidney pain were ADPKD manifestations of primary interest. Unadjusted and adjusted (early [G1-3a] vs late [G3b-5] chronic kidney disease [CKD]; Mayo Imaging Classification [MIC] 1B-E) general linear mixed models evaluated kidney manifestations, with time as a categorical variable. All p-values are nominal.
Results
Among 470 patients included in the analysis, UTI rates decreased significantly from 9.6% at baseline to 0.9% at month 72 (Type III p=0.0032); hematuria declined from 13.8% to 1.8% (Type III p<0.0001). Numerical reductions were seen in rates of nephrolithiasis and kidney pain (baseline: 14.3% and 24.0%; month 72: 7.2% and 9.9%, respectively). Reductions from baseline to month 72 in rates of UTIs (early CKD: 8.2% to 1.2%; late CKD: 13.4% to 0%), nephrolithiasis (early CKD: 12.6% to 9.4%; late CKD: 18.3% to 0%) and kidney pain (early CKD: 24.3% to 8.2%, late CKD: 23.9% to 12.5%) were generally similar for early vs late CKD. Hematuria declined in both subgroups, with a significant difference over time between early (baseline: 14.2%; month 72: 1.2%) vs late CKD (baseline: 13.4%; month 72: 4.2%; Type III p=0.0146). Kidney manifestation patterns through month 72 were similar across MIC classes and consistent with the overall population, although sample size was limited.
Conclusion
Long-term real-world C-MAJOR study follow-up confirms benefits of tolvaptan in clinical ADPKD progression, with improvements in kidney manifestations including UTIs, hematuria, and nephrolithiasis across CKD categories and MIC classes.
Funding
- Commercial Support – Otsuka Canada Pharmaceutical Inc.