STD Home > Treating Hepatitis B With Tenofovir and How It Works
There are two types of hepatitis B -- acute (recently acquired) and chronic (lifelong). For most people with acute hepatitis B, symptoms gradually get better within a couple of months. These people with have no long-lasting liver damage and will recover completely.
For some people, the body is not able to completely get rid of the virus. These people end up having a long-term liver infection. This is called chronic hepatitis B. People with chronic hepatitis B can infect others and are at an increased risk of serious liver disease, including cirrhosis and liver cancer.
Chronic hepatitis B treatment may include medications to help slow down the liver damage and possibly to prevent complications. Some people may be cured of the infection with such medications, but this does not happen very often. Usually, medications suppress the virus and help limit damage but cannot get rid of the virus altogether.
Tenofovir is one of the medications approved to treat chronic hepatitis B. It is not approved to treat acute hepatitis B. At this time, it is not known exactly how long people should take tenofovir for chronic hepatitis B treatment.
Tenofovir is currently the only medication in a class of HIV medications known as nucleotide reverse transcriptase inhibitors (NtRTIs). It is similar to medications in another class, nucleoside reverse transcriptase inhibitors (NRTIs). Tenofovir works by blocking a process that the HIV virus needs in order to multiply.
Like other viruses, HIV must use a person's own cells to reproduce. However, HIV is a little different from other viruses because it must first convert its genetic material from RNA to DNA. It is the DNA genes that allow HIV to multiply.
HIV converts its genetic material by using a special protein called the reverse transcriptase enzyme. To create DNA, this enzyme uses several different molecular building-blocks.
Tenofovir works by tricking reverse transcriptase into thinking it is one of these molecular building-blocks. However, it is just different enough that when used to create DNA, tenofovir actually stops the DNA from being made. Without DNA, HIV cannot multiply. Tenofovir is not a cure for HIV or AIDS, however. It can help stop HIV from infecting healthy cells in the body, but it does not help cells that have already been infected with the virus.
Tenofovir works similarly for treating chronic hepatitis B, except instead of inhibiting reverse transcriptase, it inhibits an enzyme known as HBV polymerase (a similar enzyme that helps to build DNA).