Supplementary Material for: Characteristics of Patients Who Achieve Serum Phosphorus Control on Sucroferric Oxyhydroxide or Sevelamer Carbonate: A post hoc Analysis of a Phase 3 Study

<b><i>Introduction:</i></b> Control of hyperphosphatemia in patients on dialysis remains a major challenge. <b><i>Objective:</i></b> This study evaluated predictors of serum phosphorus (sP) control among dialysis patients treated with noncalcium, oral phosphate binder therapy in a phase 3 clinical trial. <b><i>Methods:</i></b> Post hoc analyses were performed using data for patients with hyperphosphatemia who received 52 weeks of treatment with sucroferric oxyhydroxide (SFOH) or sevelamer carbonate (sevelamer). Patients were categorized into those who achieved sP control (<i>n</i> = 302; defined as sP ≤ 5.5 mg/dL at week 52), and those with uncontrolled sP (<i>n</i> = 195; sP &gt;5.5 mg/dL at week 52). Because SFOH and sevelamer have previously demonstrated similar effects on chronic kidney disease-mineral-bone disorder parameters in this study, the treatment groups were pooled. <b><i>Results:</i></b> Average age at baseline was higher among sP-controlled versus sP-uncontrolled patients (56.9 vs. 53.4 years; <i>p</i> = 0.005). Baseline sP levels were significantly lower among sP-controlled versus sP-uncontrolled patients (7.30 vs. 7.85 mg/dL; <i>p</i> &lt; 0.001), and sP reductions from baseline were significantly greater in the sP-controlled group (−2.89 vs. −0.99 mg/dL at week 52; <i>p</i> &lt; 0.001). Logistic regression analysis identified higher baseline sP levels (odds ratio [OR] = 0.86, 95% confidence interval [CI]: 0.765–0.960), no concomitant active vitamin D therapy use (OR = 0.51, 95% CI: 0.328–0.804), and higher body mass index at baseline (OR = 0.96, 95% CI: 0.937–0.992) as significant predictors of uncontrolled sP. <b><i>Conclusion:</i></b> This analysis indicates that sP control may be more challenging in younger patients with high sP levels. Closer monitoring and management of serum phosphorus levels may be required in this population.

<b><i>引言：</i></b> 透析患者高磷血症的控制仍是一项重大临床挑战。<b><i>研究目的：</i></b> 本研究针对一项Ⅲ期临床试验中接受非钙类口服磷结合剂治疗的透析患者，评估其血清磷（serum phosphorus, sP）控制的预测因素。<b><i>研究方法：</i></b> 本研究采用事后分析方法，纳入接受52周氢氧化蔗糖铁（sucroferric oxyhydroxide, SFOH）或碳酸司维拉姆（sevelamer carbonate, sevelamer）治疗的高磷血症患者。将患者分为血清磷控制组（n=302，定义为第52周时血清磷≤5.5 mg/dL）与未控制组（n=195，第52周时血清磷>5.5 mg/dL）。鉴于本研究中SFOH与sevelamer既往已被证实对慢性肾脏病-矿物质和骨异常（chronic kidney disease-mineral-bone disorder, CKD-MBD）相关参数具有相似的干预效果，故将两组治疗数据合并分析。<b><i>研究结果：</i></b> 基线时，血清磷控制组患者的平均年龄高于未控制组（56.9岁 vs 53.4岁；p=0.005）。血清磷控制组患者的基线血清磷水平显著低于未控制组（7.30 mg/dL vs 7.85 mg/dL；p<0.001），且第52周时较基线的血清磷降幅显著更大（-2.89 mg/dL vs -0.99 mg/dL；p<0.001）。Logistic回归分析显示，基线血清磷水平更高（比值比[OR]=0.86，95%置信区间[CI]：0.765~0.960）、未伴随活性维生素D治疗（OR=0.51，95%CI：0.328~0.804）以及基线体质量指数更高（OR=0.96，95%CI：0.937~0.992）是血清磷未得到有效控制的显著预测因素。<b><i>研究结论：</i></b> 本分析提示，对于基线血清磷水平较高的年轻患者，血清磷控制可能更具挑战性，该人群需加强血清磷水平的监测与管理。