Guide to Hepatitis B for People Living With HIV
Currently approved treatments are unable to completely cure HBV infection. The rate of HBsAg seroconversion, the closest measure to a cure, is less than 10%, and most people will need to stay on treatment for life. When people need to stay on therapy for decades, the development of drug resistance will likely be inevitable. New, more potent drugs with high resistance barriers are needed.
Research into HBV is difficult because the virus cannot be grown in laboratories in an efficient manner. This limitation has resulted in an incomplete understanding of the HBV viral life cycle, which makes it harder to develop new drugs that can suppress HBV in different ways. Right now, all of the approved antivirals block viral replication at the same site; this is why combinations of HBV antiviral therapies do not improve efficacy, unlike in HIV, where drugs targeting different steps in the viral replication process can be combined into effective regimens.
Since the immune system plays such an important role in HBV disease progression, there is a critical need for research into what triggers immune response in the acute-infection, immune-clearance, and reactivation phases of chronic HBV. A complete HBV cure is likely to depend on a better understanding of these mechanisms.
There is a new HBV Clinical Research Network being set up by the National Institutes of Health. This network is likely to focus on treatment strategies, such as the best use of current drugs in different phases of chronic HBV disease progression, and different drug combination strategies with newer and more potent drugs. While this development is encouraging, funding for this network is not sufficient for researchers to adequately address most of the unanswered questions in chronic HBV. The network's website is at: www.hepbnet.org.
Public investment in HBV research lags behind that for HIV and HCV. A more vocal approach to HBV research advocacy is needed to bring more attention to, and increase funding for, this disease.
Where to Find Information on New HBV Drugs
An update on HBV drugs in clinical development is included in the TAG Pipeline Report, available for download as a PDF file from the TAG website: www.treatmentactiongroup.org
Reports relating to new HBV treatment are also regularly on the National AIDS Treatment Advocacy Project (NATAP) website: www.natap.org
An ongoing, detailed list of HBV drugs in development is also available on the Hepatitis B Foundation website: hwww.hepb.org/professionals/hbf_drug_watch.htm
This article was provided by Treatment Action Group.