Bang Lynne M, Scott Lesley J
Adis International Limited, Auckland, New Zealand.
Drugs. 2003;63(22):2413-24; discussion 2425-6. doi: 10.2165/00003495-200363220-00003.
Emtricitabine, a nucleoside reverse transcriptase inhibitor, is phosphorylated by cellular enzymes to emtricitabine 5'-triphosphate which, in turn, inhibits the activity of HIV-1 (HIV) reverse transcriptase by competing with the endogenous substrate. Incorporation of the triphosphate into the viral DNA causes chain termination, thereby inhibiting viral replication. In adult patients infected with HIV, combination therapy including emtricitabine 200 mg once daily was as effective as triple therapy including lamivudine 150 mg twice daily and significantly more effective than stavudine (at standard dosages) or protease inhibitor-based therapy at achieving and/or maintaining durable suppression of HIV levels after 24-48 weeks of therapy. In addition, 85% of emtricitabine recipients maintained virological success (<400 copies/mL) during 96 weeks of therapy. Triple therapy including emtricitabine 6 mg/kg once daily decreased (to <400 copies/mL) or maintained durable suppression of HIV RNA levels in approximate, equals 90% of children and adolescents (aged 13 months to 17 years) after 16-24 weeks of therapy. Emtricitabine-based therapy was generally well tolerated; most adverse events being mild to moderate in intensity. Emtricitabine-based regimens were as well tolerated as those with lamivudine, and better tolerated than those with stavudine.
恩曲他滨是一种核苷类逆转录酶抑制剂，可被细胞酶磷酸化为5'-三磷酸恩曲他滨，后者通过与内源性底物竞争来抑制HIV-1（艾滋病毒）逆转录酶的活性。三磷酸恩曲他滨掺入病毒DNA会导致链终止，从而抑制病毒复制。在感染艾滋病毒的成年患者中，包含每日一次200mg恩曲他滨的联合疗法与包含每日两次150mg拉米夫定的三联疗法效果相当，并且在治疗24 - 48周后，在实现和/或维持对艾滋病毒水平的持久抑制方面，显著优于司他夫定（标准剂量）或基于蛋白酶抑制剂的疗法。此外，85%接受恩曲他滨治疗的患者在96周治疗期间维持了病毒学成功（<400拷贝/mL）。包含每日一次6mg/kg恩曲他滨的三联疗法在治疗16 - 24周后，使大约90%的儿童和青少年（年龄在13个月至17岁之间）的HIV RNA水平降低（至<400拷贝/mL）或维持持久抑制。基于恩曲他滨的疗法总体耐受性良好；大多数不良事件的强度为轻度至中度。基于恩曲他滨的治疗方案与拉米夫定治疗方案的耐受性相当，且比司他夫定治疗方案的耐受性更好。
