Attur Ravindra Prabhu, Indu Ramachandra Rao, Shankar Prasad Nagaraju, Eti Rajwar, Bhumika T Venkatesh, Sreekumaran Nair N, Ganesh Pai, Nageswara P Reddy, Deepak Suvarna

Hepatitis C virus (HCV) infection is common in chronic kidney disease (CKD) patients on dialysis, causes chronic liver disease, may increase the risk of death, and impacts kidney transplant outcomes. Direct-acting antivirals have replaced interferons because of better efficacy and tolerability. This is an update of a review first published in 2015. We aimed to look at the benefits and harms of interventions for HCV in CKD patients on dialysis: death, disease relapse, treatment response/discontinuation, time to recovery, quality of life (QoL), cost-effectiveness, and adverse events. We aimed to study comparisons of available interventions, compared with placebo, control, with each other and with newer treatments. We searched the Cochrane Kidney and Transplant's Specialised Register to 23 February 2023 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE and EMBASE, handsearching conference proceedings, and searching the International Clinical Trials Register Portal (ICTRP) and ClinicalTrials.gov. Randomised controlled trials (RCTs), quasi-RCTs, first period of randomised cross-over studies on interventions for HCV in CKD on dialysis were considered. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI). Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Three studies were included in this update, therefore 13 studies (997 randomised participants) met our inclusion criteria. Overall, the risk of bias was judged low in seven studies, unclear in four, low to unclear in one, and high in one study. Interventions included standard interferon, pegylated (PEG) interferon, standard or PEG interferon plus ribavirin; direct-acting antivirals, and direct-acting antivirals plus PEG interferon plus ribavirin. Compared to placebo or control, standard interferon may make little or no difference to death (5 studies, 134 participants: RR 0.89, 95% CI 0.06 to 13.23) or relapse (low certainty evidence), probably improves end-of-treatment response (ETR) (5 studies, 132 participants: RR 8.62, 95% CI 3.03 to 24.55; I² = 0%) (moderate certainty evidence), and probably makes little or no difference to sustained virological response (SVR) (4 studies, 98 participants: RR 3.25, 95% CI 0.81 to 13.07; I² = 53%), treatment discontinuation (4 studies, 116 participants: RR 4.59, 95% CI 0.49 to 42.69; I² = 63%), and adverse events (5 studies, 143 participants: RR 3.56, 95% CI 0.98 to 13.01; I² = 25%) (moderate certainty evidence). In low certainty evidence, PEG interferon (1 study, 50 participants) may improve ETR (RR 1.53, 95% CI 1.09 to 2.15) but may make little or no difference to death (RR 0.33, 95% CI 0.01 to 7.81), SVR (RR 2.40, 95% CI 0.99 to 5.81), treatment discontinuation (RR 0.11, 95% CI 0.01 to 1.96), adverse events (RR 0.11, 95% CI 0.01 to 1.96) and relapses (21/38 relapsed) (RR 0.72, 95% CI 0.41 to 1.25) compared to standard interferon. In moderate certainty evidence, high-dose PEG interferon (alpha-2a and alpha-2b) may make little or no difference to death (2 studies, 97 participants: RR 4.30, 95% CI 0.76 to 24.33; I² = 0%), ETR (RR 1.42, 95% CI 0.51 to 3.90; I² = 20%), SVR (RR 1.19, 95% CI 0.68 to 2.07; I² = 0%), treatment discontinuation (RR 1.20, 95% CI 0.63 to 2.28; I² = 0%) or adverse events (RR 1.05, 95% CI 0.61 to 1.83; I² = 27%) compared to low-dose PEG interferon. High-dose PEG interferon may make little or no difference to relapses (1 study, 43 participants: RR 1.11, 95% CI 0.45 to 2.77; low certainty evidence). There were no significant subgroup differences. Standard interferon plus ribavirin may lead to higher treatment discontinuation (1 study, 52 participants: RR 2.97, 95% CI 1.19 to 7.36; low certainty evidence) compared to standard interferon alone.  In low certainty evidence, PEG interferon plus ribavirin (1 study, 377 participants) may improve SVR (RR 1.80, 95% CI 1.46 to 2.21), reduce relapses (RR 0.33, 95% CI 0.23 to 0.48), slightly increase the number with adverse events (RR 1.10, 95% CI 1.01 to 1.19), and may make little or no difference to ETR (RR 1.01, 95% CI 0.94 to 1.09) compared to PEG interferon alone. The evidence is very uncertain about the effect of PEG interferon plus ribavirin on treatment discontinuation (RR 1.71, 95% CI 0.69 to 4.24) compared to PEG interferon alone. One study reported grazoprevir plus elbasvir improved ETR (173 participants: RR 174.99, 95% CI 11.03 to 2775.78; low certainty evidence) compared to placebo. It is uncertain whether telaprevir plus ribavirin (high versus low initial dose) plus PEG interferon for 24 versus 48 weeks (1 study, 35 participants) improves ETR (RR 1.02, 95% CI 0.67 to 1.56) or SVR (RR 1.02, 95% CI 0.67 to 1.56) because the certainty of the evidence is very low.  Data on QoL, cost-effectiveness, cardiovascular outcomes and peritoneal dialysis were not available. In dialysis patients with HCV infection grazoprevir plus elbasvir probably improves ETR. There is no difference in ETR or SVR for combinations of telaprevir, ribavirin and PEG interferon given for different durations and doses. Though no longer in use, PEG interferon was more effective than standard interferon for ETR but not SVR. Increasing doses of PEG interferon did not improve responses. The addition of ribavirin to PEG interferon may result in fewer relapses, higher SVR, and higher numbers with adverse events.