Abstract: FR-PO127
Timing of PTH Reduction with Cinacalcet (CIN) or Etelcalcetide (ETL) Treatment and Effect of Previous CIN Dose
Session Information
- Bone and Mineral Metabolism: Phosphorus, FGF23, Vascular Calcification
November 08, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Bone and Mineral Metabolism
- 402 Bone and Mineral Metabolism: Clinical
Authors
- Rastogi, Anjay, UCLA, Los Angeles, California, United States
- Zhang, Sue, Amgen Inc., Thousand Oaks, California, United States
- Rossetti, Sandro, Amgen Inc., Thousand Oaks, California, United States
- Bushinsky, David A., University of Rochester Medical Center, Rochester, New York, United States
Background
The calcimimetics ETL and CIN reduce serum parathyroid hormone (PTH) in subjects with secondary hyperparathyroidism (sHPT) on hemodialysis (HD) (NCT1896232; Block JAMA 2017). This post-hoc analysis investigated the timing of PTH reductions following CIN or ETL treatment and their relation to previous CIN treatment.
Methods
Data were derived from a phase 3, randomized, active control, dose-titration trial comparing the safety and efficacy of CIN and ETL in adults with sHPT receiving HD with PTH ≥500 pg/mL. Subjects received CIN (titrated from 30-180 mg PO QD) and IV placebo (TIW); or ETL (titrated from 5-15 mg IV TIW) and placebo (PO QD) for 26 weeks to target a PTH ≤300 pg/mL. Subjects could not have received CIN during the 3 months prior to screening. Achievement of >30% PTH reduction by 8 or 18 weeks and maintenance of the target PTH reduction during the efficacy assessment phase (weeks 20-27) were analyzed. Stratified by previous CIN dose, PTH levels over time were summarized using descriptive statistics.
Results
At baseline, subjects (N=683 [343 CIN; 340 ETL]) had a median PTH of 930 and 900 pg/mL in the CIN and ETL groups, respectively. By week 8, >70% of subjects had achieved >30% PTH reduction from baseline (Table). Of these, 80% receiving ETL vs 68% receiving CIN maintained >30% PTH reduction in weeks 20-27. By week 18, >85% of subjects had achieved >30% PTH reduction from baseline. Of these, 77% receiving ETL vs 65% receiving CIN maintained >30% PTH reduction in weeks 20-27. In both groups, subjects with a lower previous CIN dose showed mostly consistent declines in PTH over time, with the ETL group achieving a greater magnitude reduction from baseline by week 26.
Conclusion
CIN and ETL can effectively reduce PTH levels within 8 weeks, and ETL may better preserve this reduction over time.
Reduction in PTH with treatment and effect of previous CIN dose
Funding
- Commercial Support –