Sundar Shyam, Chatterjee Mitali
Kala-azar Medical Research Center, Department of Medicine, Institute of Medical Sciences Banaras Hindu University, Varanasi, India.
Indian J Med Res. 2006 Mar;123(3):345-52.
Major therapeutic obstacles in the treatment of visceral leishmaniasis (VL) include the alarming increase in antimonial unresponsiveness especially in Bihar, India and relapses in HIV-Leishmania co-infected patients. The therapeutic armamentarium for VL is currently plagued with several limitations as the available drugs are toxic, majority are effective only parenterally and need to be administered for extended periods. The first orally effective drug, miltefosine has been approved for treating VL. In antimony refractory zones, pentavalent antimony has been largely replaced by amphotericin B deoxycholate, but prolonged hospitalization, toxic effects, and requirement for monitoring greatly hamper its widespread application in endemic regions. Lipid formulations of amphotericin B, a remarkable advance in amphotericin B therapy, have greatly reduced toxicity enabling large doses to be delivered over a short period. Even a single dose treatment with liposomal amphotericin B cures > 90 per cent patients; however, the stumbling block is its prohibitive cost that precludes its widespread accessibility in endemic countries. Studies using paromomycin in VL are encouraging, and judging by the preliminary results of a recently concluded phase III trial, it could be an extremely useful and affordable antileishmanial drug. Other orally effective drugs include the azoles and allopurinol but these have met with limited success owing to either poor efficacy or unacceptable toxicity. Sitamaquine has undergone limited evaluation, and the data suggest effective antileishmanial activity; its role has to be delineated for which additional developmental studies are proposed. This review highlights the progress made in the treatment of VL, including the multiple mechanisms of action of antileishmanial drugs with a view to enable the researcher to undertake the challenge of providing affordable and effective chemotherapy.
内脏利什曼病(VL)治疗中的主要治疗障碍包括抗锑无反应性的惊人增加,尤其是在印度比哈尔邦,以及HIV-利什曼原虫合并感染患者的复发。VL的治疗药物目前存在几个局限性,因为现有药物有毒,大多数仅胃肠外给药有效且需要长期给药。第一种口服有效的药物米替福新已被批准用于治疗VL。在锑难治地区,五价锑已在很大程度上被两性霉素B脱氧胆酸盐取代,但长期住院、毒性作用以及监测需求极大地阻碍了其在流行地区的广泛应用。两性霉素B的脂质制剂是两性霉素B治疗的一项显著进展,已大大降低了毒性,能够在短时间内给予大剂量药物。即使单剂量的脂质体两性霉素B治疗也能治愈超过90%的患者;然而,障碍在于其高昂的成本,这使得其在流行国家无法广泛获得。在VL中使用巴龙霉素的研究令人鼓舞,从最近完成的一项III期试验的初步结果判断,它可能是一种极其有用且价格合理的抗利什曼原虫药物。其他口服有效的药物包括唑类和别嘌醇,但由于疗效不佳或毒性不可接受,这些药物取得的成功有限。西他喹啉的评估有限,数据表明其具有有效的抗利什曼原虫活性;其作用有待明确,为此提出了进一步的开发研究。本综述强调了VL治疗中取得的进展,包括抗利什曼原虫药物的多种作用机制,以期使研究人员能够应对提供负担得起的有效化疗这一挑战。