Abstract
Background and Aims
The aim of this retrospective, real-world data based observational study was to evaluate the efficacy, safety profile of paricalcitol in Chinese hemodialysis (HD) patients with secondary hyperparathyroidism (SHPT) under routine clinical practice.
Method
From the Zemplar Engagement Program (ZEP) database, a total of 668 Chinese hemodialysis patients from 104 dialysis centers between January 2015 and May 2019 were included in the analysis set. Intact parathyroid hormone (iPTH), total serum calcium (Ca), phosphate (P), dosage of intravenous (IV) paricalcitol (Zemplar®) were analyzed and discussed via retrospective analysis of the database during the treatment. The comparison between baseline and end of treatment was made to reveal the fluctuation trend of each biomarker and reflected us with clues of IV paricalcitol’s algorithm in real-world practice.
Results
Patients were divided into five groups according to the duration of follow-up, which includes Month 0.5-3 (Day 14–90), Month 3-6 (Day 91–180), Month 6-12 (Day 181–360), Month 12-24 (Day 361–720) and Month 24-48 (Day 721–1440). Median iPTH levels decreased from 1183.05 pg/ml at baseline to 676.03 pg/ml at last visit by 30.88% (p < 0.0001). 56.14% of patients had a ≥30% decrease and 29.34% of patients had a ≥50% decrease in iPTH. The proportion of patients achieving the Chinese CKD-MBD Guideline target range (<600 pg/ml) increased from 9.88% at treatment initiation to 40.12% at last observation. Serum Ca levels remained within the normal range throughout the study with only a slight but statistically significant increase in the group of Month 12-24 (P=0.0479). Serum phosphate remained stable in all follow-up groups (P>0.05). Subgroup analyses of 221 patients with hyperphosphatemia at baseline >1.78 mmol/l showed a rapid phosphate reduction from 2.00±0.20 mmol/l to 1.76±0.34mmol/l by 11.64% (P< 0.0001), within the first few weeks, along with the reduction of iPTH. Of all patients, 62.72% experienced a 30% decrease in iPTH within a median time of 16.86 weeks (95% CI, 15.57-17.86), 38.17% experienced a 50% decrease in iPTH within a median time of 21.29 weeks (95% CI, 19.86-23.14). The average weekly dose of paricalcitol was 19.69±8.99ug/week. Total dose of paricalcitol used and baseline iPTH were negatively correlated with the decrease in iPTH.
Conclusion
This is the first national retrospective real-world observational study since IV paricalcitol is available in China since 2014. It proves that up to 20ug weekly IV paricalcitol treatment is safe and effective in China HD patients with higher iPTH level. Physicians and patients could expect significantly iPTH decrease within 16-21 weeks when IV paricalcitol is initiated. This study also encores the pre-published results of paricalcitol trials and high-quality cohorts, from the real-world perspective. In summary, IV paricalcitol is well tolerated and serves as an effective approach to treat SHPT in Chinese HD patients.
Figure.1 Mean iPTH values from baseline to last measurement (pg/ml)
Figure.2 iPTH changes compared with baseline stratified by baseline iPTH values (%)
Figure.3 Proportion of patients with a >=30% or 50% decrease in parathyroid hormone (%)
Figure.4 Changes of iPTH and P from baseline to last measurement in the subgroup of hyperphosphatemia (Mean ± SD); (Hyperphosphatemia, defined as P>1.78 mmol/l)
Parathyroid hormone-producing cells exist in adipose tissues surrounding the parathyroid glands in hemodialysis patients with secondary hyperparathyroidism
