Abstract: Objective: To evaluate the efficacy and safety of cinacalcet in maintenance hemodialysis patients with varying severity of secondary hyperparathyroidism (SHPT). Methodology: This open-label, parallel-group, multicenter study consisted of a 32-week cohort study followed by a 20-week post-trial follow-up. Patients were stratified by baseline iPTH levels into mild (≥300 pg/mL and <600 pg/mL), moderate (≥600 pg/mL and <900 pg/mL), or severe (≥900 pg/mL) categories. During the cohort study, participants received oral cinacalcet once daily, titrated from 25mg to 100mg, to achieve a target iPTH of ≥150 pg/ml and <300 pg/mL alongside conventional therapy. In the post-trial follow-up, patients chose whether to continue cinacalcet at their own expense. The primary efficacy outcome was the proportion of patients achieving the target iPTH level at weeks 20 and 32. Results: A total of 750 patients were enrolled, including 275 with mild, 224 with moderate, and 251 with severe SHPT. The primary efficacy outcome was achieved by 35.5%, 28.3%, and 12.4% of patients in the mild-to-severe groups, respectively, at week 20 (P<0.001). By week 32, these rates increased to 41.2%, 27.7%, and 15.9%, respectively (P<0.001). Cinacalcet significantly reduced serum calcium, phosphorus, and fibroblast growth factor 23 (FGF-23) levels across all SHPT severity groups. Higher cinacalcet doses and increased hypocalcemia incidence were observed in patients with more severe SHPT. During the post-trial follow-up, 40.0% and 47.6% of patients maintained ≥30% reductions in iPTH and FGF-23, respectively. Conclusion: These findings support initiating cinacalcet treatment at an early stage of SHPT in patients on maintenance hemodialysis. However, attention should be paid to treatment-related adverse events.

Key words: font-family:Inter, -apple-system, BlinkMacSystemFont, ", font-size:16px, background-color:#FFFFFF, ">cinacalcet, maintenance hemodialysis, secondary hyperparathyroidism, parathyroid hormone, fibroblast growth factor 23