Hydroxyurea (Hydroxycarbamide), an antineoplastic agent, inhibits DNA synthesis through the inhibition of ribonucleoside diphosphate reductase.

Hydroxyurea能够抑制HIV-1复制。体外实验显示，对激活的PBMC中HIV-1实验室株，Hydroxyurea的90%抑制浓度（IC90）为0.4 mM。研究还发现Hydroxyurea与核苷逆转录酶抑制剂二氮嘧啶（didanosine）具有协同增效作用，可通过减小脱氧核苷三磷酸池大小来抑制激活PBMC中的HIV-1复制。Hydroxyurea已被证实能增敏对二氮嘧啶耐药的突变体[1][2]。Hydroxyurea在镰状细胞性贫血治疗中显示出活性，它通过增加胎儿血红蛋白的产量，从而减少了患者的溶血现象。Hydroxyurea通过抑制核糖核苷酸还原酶（负责核糖核苷酸向脱氧核糖核苷酸转换的速率限制酶）展现其细胞静止效果，促进细胞分裂在S期被阻断[1]。

Hydroxyurea 治疗在17周内持续降低WBC(白细胞)和ANC(绝对中性粒细胞)计数，但并未改善贫血症状。而以每公斤体重50 mg剂量的 Hydroxyurea 较之于对照化合物处理的镰状细胞鼠，WBC和ANC计数减少，但对贫血无改善效果[5]。

Erythroid cells obtained from peripheral blood of the same patients(Thirteen β-Thal/HbE patients are treated with hydroxyurea orally for 2 years at a starting dose of 5 mg/kg/day for 5 days/week with escalation to a maximum of 10 mg/kg/day) 1 year after they had stopped hydroxyurea treatment are treated with hydroxyurea in vitro.Treatment of cells performs in primary culture with 30 μM hydroxyurea for 96 hours.(Only for Reference)