Emtricitabine (BW1592; FTC; Coviracil; Emtriva; Racivir) is a potent nucleoside reverse transcriptase inhibitor (NRTI) with an EC50 of 0.01 μM and has been used for the treatment of both human immunodeficiency virus (HIV) and hepatitis B virus. Emtricitabine is structurally similar to Lamivudine. It is effective at targeting HIV and HBV viruses since these viruses replicate in a reverse transcriptase manner. Studies indicate that the structure of Emtricitabine, specifically the unnatural β-L structural configuration produce greater antiviral effects in vitro on HIV and HBV than other antiviral agents. nucleoside reverse transcriptase inhibitor.