Antiviral drug having dual antiviral activity against HIV and HBV is:

Emtricitabine (FTC), with trade name Emtriva (formerly Coviracil), is a nucleoside reverse transcriptase inhibitor (NI) for the treatment of HIV infection in adults and children.Emtricitabine is always used in combination with other HIV medicines. Because emtricitabine is also effective against HBV, it may be included in an HIV regimen to treat HBV infection in people with HIV. In addition to emtricitabine, the HIV regimen should include another drug that is effective against both HBV and HIV. Emtricitabine should not be used to treat HBV infection in HIV-infected individuals who are not receiving A. REFERANCE:aidsinfo.nih.gov,en.wikipedia.org