Systematic review with meta-analysis: vasoactive drugs for the treatment of hepatorenal syndrome type 1

Background Hepatorenal syndrome type 1 (HRS1) is a functional, rapidly progressive, potentially reversible form of acute kidney injury occurring in patients with cirrhosis. Characterised by intense renal arterial vasoconstriction, it carries a very poor prognosis. There is a significant unmet need for a widely approved, safe and effective pharmacological treatment. Aim To re-evaluate efficacy and safety of pharmacological treatments for HRS1, in the light of recently published randomised controlled trials (RCTs). Methods MEDLINE (OvidSP), EMBASE, PubMed and Cochrane registers were searched for RCTs reporting efficacy and adverse events related to pharmacological treatment of HRS1. Search terms included: ‘hepatorenal syndrome’, ‘terlipressin’, ‘noradrenaline’, ‘octreotide’, ‘midodrine’, ‘vasopressin’, ‘dopamine’, ‘albumin’ and synonyms. Comparison of vasoactive drugs vs. placebo/no treatment, and two active drugs were included. Meta-analysis was performed for HRS1 reversal, creatinine improvement, mortality and adverse events. Results Twelve RCTs enrolling 700 HRS1 patients were included. Treatment with terlipressin and albumin led to HRS1 reversal more frequently than albumin alone or placebo (RR: 2.54, 95% CI: 1.51–4.26). Noradrenaline was effective in reversing HRS1, but trials were small and nonblinded. Overall, there was mortality benefit with terlipressin (RR: 0.79, 95% CI: 0.63–1.01), but sensitivity analysis including only trials with low risk of selection bias weakened this relationship (RR: 0.87, 95% CI: 0.71–1.06). Notably, there was a significant risk of adverse events with terlipressin therapy (RR: 4.32, 95% CI: 0.75–24.86). Conclusions Terlipressin treatment is superior to placebo for achieving HRS1 reversal, but mortality benefit is less clear. Terlipressin is associated with significant adverse events, but infusion regimens may be better tolerated. There is continued need for safe and effective treatment options for hepatorenal syndrome

Serelaxin as a potential treatment for renal dysfunction in cirrhosis: Preclinical evaluation and results of a randomized phase 2 trial

<div><p>Background</p><p>Chronic liver scarring from any cause leads to cirrhosis, portal hypertension, and a progressive decline in renal blood flow and renal function. Extreme renal vasoconstriction characterizes hepatorenal syndrome, a functional and potentially reversible form of acute kidney injury in patients with advanced cirrhosis, but current therapy with systemic vasoconstrictors is ineffective in a substantial proportion of patients and is limited by ischemic adverse events. Serelaxin (recombinant human relaxin-2) is a peptide molecule with anti-fibrotic and vasoprotective properties that binds to relaxin family peptide receptor-1 (RXFP1) and has been shown to increase renal perfusion in healthy human volunteers. We hypothesized that serelaxin could ameliorate renal vasoconstriction and renal dysfunction in patients with cirrhosis and portal hypertension.</p><p>Methods and findings</p><p>To establish preclinical proof of concept, we developed two independent rat models of cirrhosis that were characterized by progressive reduction in renal blood flow and glomerular filtration rate and showed evidence of renal endothelial dysfunction. We then set out to further explore and validate our hypothesis in a phase 2 randomized open-label parallel-group study in male and female patients with alcohol-related cirrhosis and portal hypertension. Forty patients were randomized 1:1 to treatment with serelaxin intravenous (i.v.) infusion (for 60 min at 80 μg/kg/d and then 60 min at 30 μg/kg/d) or terlipressin (single 2-mg i.v. bolus), and the regional hemodynamic effects were quantified by phase contrast magnetic resonance angiography at baseline and after 120 min. The primary endpoint was the change from baseline in total renal artery blood flow.</p><p>Therapeutic targeting of renal vasoconstriction with serelaxin in the rat models increased kidney perfusion, oxygenation, and function through reduction in renal vascular resistance, reversal of endothelial dysfunction, and increased activation of the AKT/eNOS/NO signaling pathway in the kidney. In the randomized clinical study, infusion of serelaxin for 120 min increased total renal arterial blood flow by 65% (95% CI 40%, 95%; <i>p <</i> 0.001) from baseline. Administration of serelaxin was safe and well tolerated, with no detrimental effect on systemic blood pressure or hepatic perfusion. The clinical study’s main limitations were the relatively small sample size and stable, well-compensated population.</p><p>Conclusions</p><p>Our mechanistic findings in rat models and exploratory study in human cirrhosis suggest the therapeutic potential of selective renal vasodilation using serelaxin as a new treatment for renal dysfunction in cirrhosis, although further validation in patients with more advanced cirrhosis and renal dysfunction is required.</p><p>Trial registration</p><p>ClinicalTrials.gov <a href="https://clinicaltrials.gov/ct2/show/NCT01640964" target="_blank">NCT01640964</a></p></div