Professor Sievert has a long-term interest in liver disease and directs an active clinical research unit comprising physician-scientists, clinical research nurses and research students.

The Clinical Research Unit has been continuously active over ten years and regularly contributes to international trials of new antiviral agents for hepatitis B and C in addition to developing and leading national investigator-initiated studies. He also directs a basic research laboratory investigating mechanisms of inflammatory liver injury and hepatic fibrogenesis, with a translational focus on identification and development of potential hepatic antifibrotic agents.