Abstract: TH-PO169
Tenapanor Reduces Serum Phosphate with Similar Efficacy and Tolerability Profiles When Added to Various Phosphate Binders
Session Information
- CKD-MBD: Clinical
October 24, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Bone and Mineral Metabolism
- 502 Bone and Mineral Metabolism: Clinical
Authors
- Sprague, Stuart M., NorthShore University HealthSystem University of Chicago, Chicago, Illinois, United States
- Tietjen, David P., Nephrology Consultants, Huntsville, Alabama, United States
- Roesch, Jesslyn, Apogee Clinical Research, Huntsville, Alabama, United States
- Yang, Yang, Ardelyx Inc, Waltham, Massachusetts, United States
- Zhao, Suling, Ardelyx Inc, Waltham, Massachusetts, United States
- Edelstein, Susan A., Ardelyx Inc, Waltham, Massachusetts, United States
- Rosenbaum, David P., Ardelyx Inc, Waltham, Massachusetts, United States
- Spiegel, David M., Ardelyx Inc, Waltham, Massachusetts, United States
Background
Tenapanor (TEN) is approved to reduce serum phosphorus (P) in adults with chronic kidney disease on dialysis as add-on therapy in patients (pts) who have an inadequate response to phosphate binders (PBs) or who are intolerant of any dose of PBs. While PBs are generally required in hyperphosphatemia management, they often cause gastrointestinal side effects of varying severity and have a high pill burden. This post hoc analysis examines the efficacy and tolerability of TEN when added to different PBs.
Methods
In the Ardelyx-supported AMPLIFY (NCT03824587) and OPTIMIZE (NCT04549597) trials, pts on maintenance dialysis with uncontrolled serum P (P ≥5.5 and >5.5 mg/dL, respectively), despite stable PB doses, received TEN. In AMPLIFY, TEN was added to baseline (BL) PB therapy, which remained stable during the 4-week efficacy period. In OPTIMIZE (cohort 2), TEN was added to BL PB which was then reduced by ≥50%. After week 2, PB could be dose adjusted to achieve P ≤5.5 mg/dL during the 10-week efficacy and 16-week open-label extension periods.
Results
In AMPLIFY, P decreased when TEN was added to sevelamer (SEV)-based and non–SEV based PB regimens, with no appreciable difference in least-squares mean P reductions at week 4 between SEV- (0.9 mg/dL, n=60) and non-SEV based (1.1 mg/dL, n=56) regimens. In OPTIMIZE, a mean P reduction of 1.0 mg/dL was achieved at the end of the 10-week treatment period, regardless of whether TEN was added to PB regimens including SEV (n=52) or not including SEV (n=80). Diarrhea was the only adverse reaction that occurred in >5% of pts; pooled rates were similar when TEN was added to SEV alone (38.9%; 42/108), calcium-based PB alone (46.8%; 22/47), iron-based PB alone (33.3%; 18/54), lanthanum carbonate alone (28.6%; 2/7), and multiple PB types (56.6%; 30/53). Study discontinuation rates in pooled analyses were similar when TEN was added to SEV alone (13.0%; 14/108), calcium-based PB alone (8.5%; 4/47), iron-based PB alone (16.7%; 9/54), lanthanum carbonate alone (14.3%; 1/7), and multiple PB types (9.4%; 5/53).
Conclusion
TEN provides a clinically meaningful serum P reduction with similar efficacy and tolerability when added to PBs, regardless of the type of PB.
Funding
- Commercial Support – Ardelyx, Inc.