| Assessing liver fibrosis in clinical trials, William Rosenberg of University College London points to the impact made by individual direct markers
Chronic liver disease is now the second most common cause of death in middle-aged men and the fifth most common cause of death in the UK overall. Out of the top five causes of death it is the only disease that is increasing. The pharmaceutical and biotechnology industries are recognising the worldwide impact of chronic viral hepatitis, alcoholic liver disease and non-alcoholic fatty liver disease (NAFLD) as well as the earning potential for new therapeutic interventions and diagnostic tests. The development of new drugs in particular is dependent on the availability of biomarkers that permit the earliest possible ‘go/no-go’ decisions and provide evidence of efficacy which ensure that drug development is rapid, efficient and safe.
The clinical impact of all chronic liver diseases (CLD) can be attributed to liver fibrosis that may progress to cirrhosis, which in turn results in the complications of portal hypertension (bleeding varices, ascites or encephalopathy), liver failure, hepatocellular cancer and death or liver transplantation. It has been recognised for decades that interventions directed at the causes of CLD can reverse the consequences of liver disease by reversing liver fibrosis. This has been established in clinical trials for the use of anti-viral agents for hepatitis B or hepatitis C, for life modifications including abstinence from alcohol and weight reduction and is integral to the investigation of drugs targeting insulin resistance that underlies NAFLD.
Now, insights into the biology of liver fibrosis have created the possibility of developing anti-fibrotic drugs that target hepatic stellate cells that are central to the production and degradation of liver matrix in fibrosis. The development of this new class of drugs targeted at the fibrotic process rather than individual causes of CLD that have broad applicability, is dependent on accurate biomarkers that are fit for purpose for use in clinical trials. LIVER BIOPSY
For almost half a century the liver biopsy has been regarded as the standard method for assessing liver fibrosis. Careful histological examination of a biopsy by an expert pathologist remains a vital asset in the diagnosis of liver disease. However, the place of liver biopsy in the assessment of liver fibrosis is increasingly questioned. Recent research has shown that liver biopsy is associated with many problems. For the patient and funder it is painful, hazardous and costly. |
