Goldberg D I, Dillon M A, Slatopolsky E A, Garrett B, Gray J R, Marbury T, Weinberg M, Wombolt D, Burke S K
GelTex Pharmaceuticals, Inc, Waltham, Massachusetts 02154, USA.
Nephrol Dial Transplant. 1998 Sep;13(9):2303-10. doi: 10.1093/ndt/13.9.2303.
Control of dietary phosphate absorption in end-stage renal disease patients is essential to prevent the deleterious sequelae of phosphorus retention. Efficacy of currently available calcium- and aluminium-containing phosphate binders is constrained by the side-effects associated with the absorption of calcium and aluminium. The current study examined the efficacy of RenaGel, a calcium- and aluminium-free, polymeric phosphate binder, in end-stage renal disease patients.
Administration of calcium- or aluminium-containing phosphate binders ceased during a 2-week washout period. RenaGel, at starting doses of one, two, or three 500-mg capsules three times per day with meals, was administered for 8 weeks. RenaGel dose was titrated up 1 capsule per meal at the end of each 2-week period if necessary to achieve phosphorus control. A second 2-week washout period followed the end of RenaGel treatment.
Mean serum phosphorus rose from a pre-washout level of 6.9 mg/dl (2.23 mmol/l) to 8.1 mg/dl (2.62 mmol/l) at the end of the initial 2-week washout. With RenaGel treatment, serum phosphorus declined and returned to pre-washout levels after 4 weeks. Serum phosphorus reached a nadir of 6.5 mg/dl (2.10 mmol/l) after 7 weeks of RenaGel treatment. Serum phosphorus rose to 8.2 mg/dl (2.65 mmol/l) 2 weeks after cessation of RenaGel treatment. As anticipated, calcium declined during the initial washout period when calcium-based phosphate binders were stopped for the majority of patients. The rise in serum phosphorus and decline in serum calcium during washout resulted in an increase in median intact parathyroid hormone (iPTH) levels from 292 pg/ml to 395 pg/ml. iPTH fell to 283 pg/ml after 6 weeks of RenaGel treatment despite a persistently lower serum calcium. RenaGel treatment also reduced serum total and LDL cholesterol by 25 mg/dl (0.65 mmol/l) and 23 mg/dl (0.59 mmol/l) respectively.
RenaGel appears to be an effective phosphate binder free of calcium and aluminium. Phosphorus control with two to four RenaGel capsules per meal appears to result in comparable phosphorus lowering seen with calcium- or aluminium-based phosphate binders. RenaGel may offer an alternative for the control of phosphorus retention in end-stage renal disease patients.
控制终末期肾病患者的饮食磷吸收对于预防磷潴留的有害后果至关重要。目前可用的含钙和含铝磷结合剂的疗效受到与钙和铝吸收相关的副作用的限制。本研究考察了一种不含钙和铝的聚合磷结合剂RenaGel在终末期肾病患者中的疗效。
在为期2周的洗脱期内停止使用含钙或含铝的磷结合剂。给予RenaGel，起始剂量为每日三次，每次一、二或三粒500毫克胶囊，随餐服用，持续8周。如有必要，在每2周结束时将RenaGel剂量每餐增加1粒胶囊，以实现磷控制。RenaGel治疗结束后紧接着是第二个2周的洗脱期。
在最初的2周洗脱期结束时，平均血清磷从洗脱前的6.9毫克/分升（2.23毫摩尔/升）升至8.1毫克/分升（2.62毫摩尔/升）。经RenaGel治疗后，血清磷下降，并在4周后恢复到洗脱前水平。RenaGel治疗7周后血清磷降至最低点6.5毫克/分升（2.10毫摩尔/升）。RenaGel治疗停止2周后，血清磷升至8.2毫克/分升（2.65毫摩尔/升）。正如预期的那样，在最初的洗脱期，当大多数患者停用钙基磷结合剂时，钙水平下降。洗脱期血清磷升高和血清钙下降导致完整甲状旁腺激素（iPTH）中位数水平从292皮克/毫升升至395皮克/毫升。尽管血清钙持续较低，但RenaGel治疗6周后iPTH降至283皮克/毫升。RenaGel治疗还使血清总胆固醇和低密度脂蛋白胆固醇分别降低了25毫克/分升（0.65毫摩尔/升）和23毫克/分升（0.59毫摩尔/升）。
RenaGel似乎是一种有效的不含钙和铝的磷结合剂。每餐服用两到四粒RenaGel胶囊控制磷的效果似乎与含钙或含铝的磷结合剂相当。RenaGel可能为控制终末期肾病患者的磷潴留提供一种替代方法。
