CYSTEAMINE VS. CYSTAMINE TREATMENT OF CORNEAL CRYSTAL ACCUMULATION

一项成功的半胱胺与安慰剂对照临床试验， 证明了半胱胺滴眼液治疗去除 来自肾病性胱氨酸病患者的晶体。 因为半胱胺 在室温下配制制剂， 半胱胺氧化二硫化物半胱胺，已经提出， 研究这种更稳定的化合物的安全性和有效性。 到目前为止， 还没有关于二硫化物的临床功效的研究， 尽管目前的猜测是，该化合物将是 在相似的浓度下都是活性的。 无动物模型 存在胱氨酸病;临床疗效只能通过 有限的人体临床试验。 然而，在此之前， 毒性是必要的，在兔子中进行了一项研究，以确定 二硫化物化合物在其用于一种 临床试验 24只家兔进行了双盲观察， 半胱胺二硫化物的眼毒性试验研究，胱胺。 完整的数据是可用的，但总的来说，反应0.5%， 而1%的人与安慰剂组基本上没有区别。 胱胺 2%的人表现出临床和组织病理学证据， 睑炎和结膜炎。 本研究将进行一项随机， 半胱胺与胱胺治疗糖尿病的对照双盲临床试验 从角膜中去除晶体和保持 “无晶体”或接近无晶体的角膜。

A successful, controlled clinical trial of cysteamine vs. placebo has proved the efficacy of cysteamine eyedrops in the treatment of removing crystals from patients with nephropathic cystinosis. Because cysteamine preparation is dispensed at room temperature and room temperature cysteamine oxidizes the disulfide cysteamine, it has been suggested that this more stable compound be studied for safety and efficacy. To date, there have been no studies on the clinical efficacy of the disulfide, although current speculation is that the compound will be pharmacologically active at similar concentrations. No animal model for cystinosis exists; clinical efficacy can be determined only through limited human clinical trials. Preceding this, however, experience with toxicity was necessary, and a study was performed in rabbits to determine the range of toxicity of the disulfide compound prior to its use in a clinical trial. Twenty-four rabbits were observed in a double-blind study for ocular toxicity testing of cysteamine disulfide, cystamine. Complete data are available, but in summary, the reaction to 0.5 percent and 1 percent was essentially no different from the placebo. Cysteamine 2 percent showed both clinical and histopathologic evidence of blepharitis and conjunctivitis. This study is to perform a randomized, controlled, double-masked clinical trial of cysteamine vs. cystamine for equivalency in removing crystals from the cornea and in maintaining a "crystal-free" or near crystal-free cornea.