Driven by rising rates of obesity and diabetes, nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are replacing hepatitis C virus infection as the most common cause of chronic liver disease worldwide. With no Food and Drug Administration (FDA)-approved treatments available, patients confront a substantial unmet need.
However, the prospects for drug development have begun to brighten as understanding of liver disease pathophysiology, diagnosis, epidemiology and natural history evolve at a remarkable pace. Recent technological advances have resulted in the development of new approaches to assessing the degree of fibrosis caused by these conditions. Also, new quantitative liver function tests that define the severity and prognosis of liver disease by measuring the clearance of substrates hold promise as noninvasive measures of liver function.