A Surveillance Program for the Detection of Hepatitis B Virus (HBV) Resistance to Tenofovir in HIV-HBV co-Infected Patients

  • participants needed
  • sponsor
    Bayside Health
Updated on 7 November 2020
antiviral drugs


Human immunodeficiency virus/Hepatitis B virus (HIV/HBV) co-infections are frequently observed due to shared routes of transmission, with reported figures indicating 6-9% of HIV-infected individuals in developed countries are chronically infected with HBV. HIV infection impacts on the natural progression of HBV infection, increasing levels of HBV replication and the risk of liver-associated mortality. Liver diseases associated with HBV are affected by the antiviral drugs used for HIV infection (toxic side effects), the current immune function in the patient, by improvements in the immune system brought about by control of the HIV infection, and by the development of resistance to the antiviral agents used for both the hepatitis B and the HIV infection. Tenofovir (TDF) is a newer antiviral drug that is frequently used for HIV infection and is also highly active against hepatitis B; however it is still unknown whether resistance to TDF will eventually develop and how this will affect the long-term outcomes


Tenofovir disoproxil fumarate (TDF) is a nucleotide analogue that can inhibit both HIV and HBV DNA polymerases, and is active against wild-type HBV and HBV strains that contain lamivudine-associated polymerase gene mutations (Dore, Cooper et al. 2004). TDF was approved for use, in combination with other antiretrovirals, for HIV therapy in April 2002 in Australia. It is not currently approved for use in Australia for treatment of HBV mono-infection. TDF has only recently become available in Thailand where HIV/HBV co-infected individuals are predominantly infected with genotype B and C. In contrast, in Australia and Europe, the dominant HBV genotype in HIV/HBV co-infected individuals is A and D. As with all antiviral agents there is concern with long-term use and the development of resistance. There has been a report of a signature mutation leading to TDF resistance at rtA194T (Sheldon et al., 2005). We recently conducted a retrospective study of HIV/HBV co infected individuals in Melbourne who had received TDF for at least 3 months. Twenty-eight patients had samples available on TDF of which four (~14%) had detectable HBV DNA by PCR. We did not identify the mutation rtA194T or rtV214A/Q215S in individuals failing TDF and found that the only persisting mutations were LMV-resistant mutations. These findings highlight the need for a surveillance system for HIV-HBV co-infected individuals receiving TDF for the detection of novel mutations in the four major HBV genotypes. In addition, it is important to determine the clinical and virological risk factors for TDF failure. This is particularly important given that these agents will be used indefinitely in this patient population and with the development of unique drug resistant mutations there will be implications for progression of liver disease and future therapeutic choices. This study will recruit patients who are co-infected with HIV and HBV, and are currently taking or who are about to commence the anti-HIV drug TDF. The study cohort will include HIV-HBV co-infected individuals from the Alfred Hospital and Melbourne Sexual Health Clinic. Other sites, not covered by this application, are St Vincent's Hospital, Sydney and King Chulalongkorn Memorial Hospital, Bangkok, Thailand. The aim of the study is to identify any changes in the HBV DNA that might be associated with resistance to TDF, to determine how long any changes take to occur and to determine the effect of these changes on the clinical response to TDF. This will be achieved by 6 monthly assessment over a 2 year period, with medical history, physical examination, routine clinical investigations, hepatitis B activity and HBV DNA sequencing.

Condition HIV infection, Hepatitis B Virus
Clinical Study IdentifierNCT00660361
SponsorBayside Health
Last Modified on7 November 2020


How to participate?

Step 1 Connect with a site
What happens next?
  • You can expect the study team to contact you via email or phone in the next few days.
  • Sign up as volunteer to help accelerate the development of new treatments and to get notified about similar trials.

You are contacting

Investigator Avatar

Primary Contact


Phone Email

Please verify that you are not a bot.

Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.

Learn more

If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.

Learn more

Complete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.

Learn more

Similar trials to consider


Browse trials for

Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note