Efficacy of AST-120 for Patients With Chronic Kidney Disease: A Network Meta-Analysis of Randomized Controlled Trials

Abstract

AST-120, an oral spherical activated carbon, may delay the need for kidney dialysis and improve uremia symptoms because it can adsorb acidic and basic organic compounds, especially small-molecule uremic toxins. However, previous studies produced no conclusive evidence regarding the benefits of AST-120 in delaying the progression of chronic kidney disease (CKD). Therefore, this systematic review and network meta-analysis evaluated the effects of AST-120 in patients with CKD. Related keywords of CKD and AST-120 were used to search four databases to obtain potential evidence on this topic, and two authors individually completed evidence selection, data extraction, and quality assessment. Network meta-analysis was performed for mortality, end-stage renal disease, composite renal outcomes, and laboratory outcomes based on a frequentist approach. In total, 15 randomized controlled trials (n = 3,763) were included in the present synthesis, and the pooled results revealed non-significant differences in mortality among the treatment strategies. Low- and high-dose AST-120 were not superior to no AST-120 treatment regarding renal outcomes. However, the event rates of end-stage renal disease (risk ratio [RR] = 0.78, 95% confidence interval [CI] = 0.62-0.99) and composite renal outcomes (RR = 0.78, 95% CI: 0.63-0.97) were significantly lower in the tailored-dose AST-120 group than in no AST-120 group. The results did not reveal a small-study effect on the outcomes. Tailored dosing of AST-120 appeared to represent an optimal treatment strategy because it resulted in lower rates of composite renal outcomes and end-stage renal disease.

Keywords: adsorbent; chronic renal failure; kremezin; sorbent; uremic toxin.

FIGURE 1

Flowchart of the systematic review and meta-analysis according to PRISMA guidelines. CKD, chronic kidney disease; CRO, composite renal outcome; IS, indoxyl sulfate; RCT, randomized controlled trial; SCr, serum creatinine.

FIGURE 2

Network plots of (A) end stage renal disease, (B) composite renal outcome, (C) mortality, (D) serum creatinine slope, (E) creatinine clearance, and (F) indoxyl sulfate change. ESRD, end stage renal disease. Green, yellow, and red refers to low risk, some concerns, and high risk of bias respectively.

FIGURE 3

Forest plots of (A) end stage renal disease, (B) composite renal outcome, and (C) serum creatinine slope. CI, confidence interval; ESRD, end stage renal disease; RR, risk ratio. Blue diamond and line indicate statistically significant findings.