Hepatitis B Treatment Not necessarily a life-long commitment
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here is a common view that once you start hepatitis B treatment, you will be on it for life. This is changing. In recent years, numerous studies have been done looking into the notion of a functional cure for hepatitis B which, when achieved, means therapy can be stopped. What is functional cure? Current hepatitis B treatment cannot completely cure the disease; the aim of current therapy is to suppress the virus sufficiently to prevent liver cirrhosis, liver failure or liver cancer, and thus improve survival. The hepatitis B virus embeds bits of itself in the host cell, allowing it to reactivate and replicate. Current therapy
cannot eradicate this remnant of the virus, which is known as the covalently combined closed DNA (cccDNA). For complete cure to happen, the cccDNA must be eliminated, not merely silenced. The virus also produces other bits of itself in its replication process. Some hepatitis B treatment drugs target various parts of this process, while others seek to enhance the body’s immune system to fight against the virus. A functional cure is a state where the other elements of the virus are eliminated or reduced to the point where the risk of adverse outcomes such as liver failure, is minimal, even though the cccDNA remains. People who have chronic
hepatitis B have various bits of the virus in their blood as a result of the virus replication process. The presence or absence of these bits act as markers for working out which stage the disease is at. One of these bits, known as the hepatitis B surface antigen (HBsAg) is the key marker that a person has chronic hepatitis B. Studies have shown that the level at which it exists in the blood is a good indicator of whether the disease is under control. Generally speaking, the indicators that treatment is working in achieving the goals of maintaining liver health and improving survival are: •
normal ALT levels,
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loss of hepatitis B surface antigen (HBsAg),
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undetectable hepatitis B DNA, and
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the appearance of hepatitis B e-antibodies (antiHBe).
Do these indicators, or end points as they are referred to, really lead to better outcomes for people? According to Prof Lim Seng Gee, Director of Hepatology at the National University of Singapore, meta-analysis
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HEPATITIS SA COMMUNITY NEWS 88 • December 2020
