it is highly synergistic. Lamivudine treatment has been shown to restore zidovudine sensitivity of previously resistant HIV. Lamivudine showed no evidence of carcinogenicity or mutagenicity in in vivo studies in mice and rats at doses from 10 to 58 times those used in humans. It has a half-life of 5–7 hours in adults and 2 hours in HIV-infected children. History Racemic BCH-189 (the minus form is known as lamivudine) was invented by Bernard Belleau while at work at McGill University and Paul Nguyen-Ba at the Montreal-based IAF BioChem International, Inc. laboratories in 1988 and the minus enantiomer isolated in 1989. Samples were first sent to Yung-Chi Cheng of Yale University for study of its toxicity. When used in combination with AZT, he discovered that lamivudine's negative form reduced side effects and increased the drug's efficiency at inhibiting reverse transcriptase. The combination of lamivudine and AZT increased the efficiency at inhibiting an enzyme HIV uses to reproduce its genetic material. As a result, lamivudine was identified as a less toxic agent to mitochondria DNA than other retroviral drugs. Lamivudine was approved by the Food and Drug Administration (FDA) on November 17, 1995, for use with zidovudine (AZT) and again in 2002 as a once-a-day dosed medication. It is on the World Health Organization's List of Essential Medicines. Formulations Epivir tablets (GlaxoSmithKline; US and UK) for the treatment of HIV Epivir-HBV tablets (GlaxoSmithKline; US only) for the treatment of hepatitis B Zeffix tablets (GlaxoSmithKline; UK only) for the treatment of hepatitis B 3TC tablets (GlaxoSmithKline; South Africa) for the treatment of HIV Lamivudine is available in fixed-dose combinations with other HIV drugs such as: Lamivudine/zidovudine (with zidovudine) Abacavir/lamivudine (with abacavir) Abacavir/lamivudine/zidovudine (with zidovudine and abacavir) Dolutegravir/lamivudine (with dolutegravir) References External links Hepatotoxins Nucleoside analog reverse transcriptase inhibitors World Health Organization essential medicines Nucleosides Pyrimidones Wikipedia medicine articles ready to translate Hydroxymethyl compounds Oxathiolanes GSK plc brands