Table 1 Characteristics of included studies. TDF received approval for the treatment of HIV infection from the United States Food and Drug Administration (FDA) in October 2001 and from the Brefeldin A ATPase European Medicines Agency in February 2002. (FDA approval for the treatment of chronic HBV infection was granted in August 2008.) The first reports of the use of TDF in treating HBV infection were presented in 2002. Web of Science, Embase and Medline were searched, including all years. Conference abstracts from The Liver Meeting (American Association for the Study of Liver Diseases), The International Liver Congress (European Association for the Study of the Liver) and the Conference on Retroviruses and Opportunistic Infections were searched for the years 2002�C2010.

To search databases, a combination of key terms was used including ��hepatitis��, ��HIV��, and ��tenofovir��, limited to articles with human subjects and written in English (Appendix S1). Conference abstracts were searched online or by hand. Other publications that were discovered from the reference lists in publications reviewed were also included. Data Collection Studies were screened initially by title and then data was collected by HP from the full article of all published studies and from conference posters, or conference abstracts if posters were not available. Some studies met the eligibility criteria except that the published report did not include data on the number with undetectable HBV viral load at one year, or information on prior or concomitant drug exposure.

The authors of these studies were contacted by email and asked to provide additional data if available. Additional, unpublished data was obtained from the authors of 11 of the 23 sources included (Table 1). The authors of one conference report provided an article that superseded the conference report and which had been accepted and published online but that had not been discovered in the search [13]. Data collected consisted of type of study, source of study funding, number of HBV/HIV coinfected participants, number HBeAg positive at study entry, prior 3TC/FTC exposure, drug regimens used during study period, length of follow-up, type of HBV viral load test used and lower limit of detection, numbers tested for HBV viral load at yearly intervals, and numbers with undetectable Dacomitinib HBV viral load at yearly intervals. To maximise power and in the absence of any evidence suggesting a difference in effect on HBV between 3TC and FTC, exposure to these two were grouped together. Results were stratified by treatment into four groups.