Background
Chronic kidney disease (CKD), defined as kidney damage or decreased kidney function for three or more months, is one of the leading causes of morbidity and mortality worldwide.1,2 It is associated with increased risk for cardiovascular events, frequent hospitalization, and death.3,4,5 For end-stage renal disease, the management is renal replacement therapy through dialysis or kidney transplantation. Locally, in 2017, hemodialysis ranked as the top procedure with the Philippine Health Insurance Corporation (PhilHealth) paying a total of Php 8.4 billion worth of claims.6
Oral adsorbents, like AST-120, are substances that bind biologically active compounds, such as uremic toxins, in the gastrointestinal tract. Through binding and eventual excretion, they minimize the accumulation of these toxins in the body. The levels of uremic toxins, such as indoxyl sulfate and p -cresyl sulfate, in the body have been shown to be associated with progression of CKD, increased cardiovascular risk, and mortality.7,8,9,10 Worsening CKD will in turn result in production of more uremic toxins leading to a vicious cycle.
AST-120 has been shown to decrease serum levels of indoxyl sulfate in rats11,12 and delay progression of CKD in animals with reduced kidney mass.13,14 Currently, based on several studies,15,16,17 some of its suggested clinical utilities among patients with chronic kidney disease (CKD) is to reduce uremic symptoms and delay the progression to renal replacement therapy and kidney transplantation.