Calcium acetate, an effective phosphorus binder in patients with renal failure

Abstract

Calcium salts are increasingly used as phosphorus binders in patients with chronic renal failure. Calcium carbonate is the principal salt presently utilized, however, other calcium salts may be more effective and safer phosphorus binders. Theoretical calculations, in vitro experiments, and in vivo studies in normal subjects have shown calcium acetate to be a more effective phosphorus binder than other calcium salts. This salt has not previously been studied in patients with chronic renal failure. We used a one-meal gastrointestinal balance technique to measure phosphorus absorption, calcium absorption and phosphorus binding in six patients with chronic renal failure. Calcium acetate was compared with calcium carbonate and placebo. Equivalent doses (50 mEq Ca++) of calcium acetate bound more than twice as much phosphorus (106 +/- 23 mg) as calcium carbonate (43 +/- 39 mg) P less than 0.05. When phosphorus binding was factored for calcium absorption, calcium acetate bound 0.44 mEq HPO4 =/mEq absorbed Ca++ compared with 0.16 mEq HPO4 = bound/mEq Ca++ absorbed with calcium carbonate. More efficient phosphorus binding permits serum phosphorus concentration to be controlled with lower doses of calcium salts. The higher phosphorus binding/calcium absorption ratio coupled with a lower dose indicates that less calcium will be absorbed when calcium acetate is used for phosphorus control. Markedly positive calcium balance, hypercalcemia and ectopic calcification should be less likely to occur with this drug than other calcium salts.

Control of Hyperphosphatemia among Patients with ESRD

“…GI washout studies have shown that the amount of phosphorus bound per amount of calcium absorbed was almost twice as great with calcium acetate compared with calcium carbonate (36). Moreover, Mai et al (37) showed that phosphorus absorption decreased to 40% of the ingested load with calcium carbonate compared with 21.7% with an equivalent amount of calcium acetate. Thus, among patients with ESRD, calcium acetate binds approximately twice the amount of phosphorus per amount of calcium absorbed (38,39).…”

Effect of Patiromer on Urinary Ion Excretion in Healthy Adults

“…This potential binding is dependent on the ambient pH as well as the ion concentration along the GI tract (1,5). The Ca ions released during the ion exchange process may be absorbed, rebind to patiromer, remain in solution as a Ca ion, or bind phosphate (P) or other anions, resulting in the formation of relatively insoluble complexes, such as Ca-P salts (9).…”

Hyperphosphatemia Management and Related Problems in Patients with End Stage Renal Disease: Review

“…33,35 Kalsiyum içe-ren fosfat bağlayıcıların başlıcaları, kalsiyum karbonat ve kalsiyum asetattır. 36,37 Kalsiyum karbonat sadece asidik ortamda çözünür. İleri böbrek yetersizliği olan çoğu hastada aklorhidri olması veya proton pompa inhibitörü, H2 reseptör blokeri gibi ilaçların kullanılması kalsiyum karbonatın çözün-mesini etkileyebilir.…”

“…37 Kalsiyum asetatın ise hem asit hem de alkali ortamda çözünebiliyor olması etkinliği için kalsiyum karbonata göre avantajdır. 36,38 Kalsiyum asetat, kalsiyum karbonat ile aynı oranda fosfor bağlarken, bunu daha düşük dozda bir elemental kalsiyum ile yapması sayesinde daha az kalsiyum yüküne yol açar. 39,40 Turkiye Klinikleri J Nephrol 2014;9(2) Diyet ve diyalize rağmen yüksek serum fosfor seviyesi olan hastalara fosfor kontrolü amaçlı tedavi olarak başlangıçta kalsiyum içeren fosfat bağ-layıcılar başlanabilir.…”