Therapeutic pipeline in nonalcoholic steatohepatitis

Our understanding of nonalcoholic fatty liver disease pathophysiology continues to advance rapidly. Accordingly, the field has moved from describing the clinical phenotype through the presence of nonalcoholic steatohepatitis (NASH) and degree of fibrosis to deep phenotyping with a description of associated comorbidities, genetic polymorphisms and environmental influences that could be associated with disease progression. These insights have fuelled a robust therapeutic pipeline across a variety of new targets to resolve steatohepatitis or reverse fibrosis, or both. Additionally, some of these therapies have beneficial effects that extend beyond the liver, such as effects on glycaemic control, lipid profile and weight loss. In addition, emerging therapies for NASH cirrhosis would have to demonstrate either reversal of fibrosis with associated reduction in portal hypertension or at least delay the progression with eventual decrease in liver-related outcomes. For non-cirrhotic NASH, it is the expectation that reversal of fibrosis by one stage or resolution of NASH with no worsening in fibrosis will need to be accompanied by overall survival benefits. In this Review, we summarize NASH therapies that have progressed to phase II and beyond. We also discuss some of the potential clinical challenges with the use of these new therapies when approved. The therapeutic pipeline for nonalcoholic steatohepatitis (NASH) is expanding as insights into disease pathophysiology are gained. This Review summarizes progress in the development of NASH therapies, current and ongoing clinical trials, and potential challenges with emerging therapies. Key points There are several novel treatments currently under development for treatment of non-cirrhotic and cirrhotic nonalcoholic steatohepatitis. Resolution of steatohepatitis and reversal of fibrosis are two important histological end points in the ongoing clinical trials. Emerging therapies are beginning to differentiate through extra-hepatic benefits such as improvement in glycaemic control, lipid profile and weight loss. Safety and tolerability of the emerging therapies will determine compliance that would result in sustained benefits and, ultimately, improvement in long-term survival.