Non-Alcoholic Fatty Liver Disease (NAFLD) is estimated to affect approximately 25-30% of the population in Western countries and is now the leading cause of chronic liver disease globally. NAFLD is a progressive liver disease and approximately 30% of individuals progress from simple steatosis to Non-Alcoholic Steatohepatitis (NASH), which can further progress to cirrhosis and hepatocellular carcinoma. In the Netherlands, it is estimated that 2.5 million people have NAFLD and this number is thought to increase by 50% in the next 10 years driven by an increasing prevalence of obesity and type 2 diabetes, and an ageing population. Independent of other cardiometabolic diseases, cardiovascular disease is the leading cause of death in individuals with NAFLD, followed by extrahepatic malignancies and liver-related complications. NAFLD results in sustained healthcare costs and economic losses, and reduced health-related quality of life.

It is now widely accepted that liver fibrosis is a result of liver injury secondary to NAFLD and is a major predictor for liver-related and overall mortality in individuals with NAFLD. The process of fibrosis progression is not completely understood, and it can vary considerably from one individual to another. Several risk factors for fibrosis progression have been identified: age, hypertension, obesity and type 2 diabetes. As of to date, no treatment is available that proved to be successful to target hepatic fibrosis. The only therapeutic options currently available therefore are the control of the concomitant metabolic diseases in addition to diet and lifestyle changes. Unfortunately, this inevitably will lead to polypharmacy and thereby decreases treatment adherence and increases the risk of adverse events and interactions with other drugs.

Recently, cellular senescence has been put forward as a causal factor in the development and progression of NAFLD and NAFLD related liver fibrosis. Cellular senescence is one of the hallmarks of aging and is defined as a stable arrest of the cell cycle coupled to specific phenotypic changes. Senescent cells secrete a collection of proteins called the senescence-associated secretory phenotype (SASP). This pro-inflammatory secretome drives age-related tissue dysfunction. Interestingly, metabolic dysregulation is thought to favor cellular senescence in several tissues involved in the pathogenesis of NAFLD such as the liver, pancreas and adipose tissue, further perpetuating metabolic dysregulation. Of interest, cellular senescence can be targeted using senolytics. The combination of dasatinib, which is an EMA-approved tyrosine kinase inhibitor and the antioxidant quercetin, which is a flavonol present in many fruits and vegetables, successfully clears senescent cells. Recent work in humans and rodents have shown that tissue function, including liver metabolism, can be recovered by clearing senescent cells with senolytics including.

Due the potential role of senescence in NAFLD related fibrosis, dasatinib plus quercetin might thus be an interesting future therapeutic option to tackle NAFLD related fibrosis. Based on the long-term safety profile of these treatments and the high unmet clinical need as there currently is no treatment for NAFLD we aim to perform a double-blind randomized controlled proof-of-principle study in which patients with NAFLD related liver fibrosis will be treated with dasatinib plus quercetin intermittently three days per week for three weeks, followed by a four-week medication-free period. Subsequently, this treatment cycle will be repeated three times