Novel approaches to develop a treatment for cryptosporidiosis

开发隐孢子虫病治疗方法的新方法

• 批准号: 8605836
• 负责人: CHRISTOPHER D HUSTON
• 金额: $ 22.88万
• 依托单位: UNIVERSITY OF VERMONT & ST AGRIC COLLEGE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-01-18 至 2015-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8605836
• 关键词: Accounting; Acquired Immunodeficiency Syndrome; Address; Affect; Biological Assay; Biological Availability; Cells; Child; Childhood; Chronic; Clinical Trials; Collection; Country; Cryptosporidiosis; Cryptosporidium; Cryptosporidium parvum; Data; Development; Diarrhea; Disease; Disease Outbreaks; Dose; Drug Combinations; Drug Kinetics; Drug usage; Economics; Enteral; Epithelial Cells; FDA approved; Goals; Gold; Growth; Growth Inhibitors; Histopathology; Human; Immunity; Immunocompetent; Immunocompromised Host; In Vitro; Infection; Intestines; Libraries; Maintenance; Microbe; Modeling; Mus; Parasites; Patients; Pharmaceutical Preparations; Pharmacodynamics; Placebos; Preclinical Drug Evaluation; Publishing; Safety; Scheme; Small Intestines; System; Testing; Therapeutic; Tissues; Toxic effect; United States; Validation; antimicrobial; base; biliary tract; clinical efficacy; combinatorial; cost; design; drug development; effective therapy; efficacy trial; follow-up; high throughput screening; in vitro Assay; in vivo; killings; microbial; microbicide; nitazoxanide; novel; novel strategies; public health relevance; safety testing; screening; success; tissue culture; waterborne

DESCRIPTION (provided by applicant): Cryptosporidiosis, due to intestinal infection with the intracellular parasites Cryptosporidium parvum or C. hominis, is the leading cause of diarrhea resulting from waterborne outbreaks in the United States, and it is a major cause of pediatric infectious diarrhea in the developing world. The infection is chronic and often fatal for immunocompromised patients, and cryptosporidiosis causes as much as 50% of chronic diarrhea in AIDS patients. Unfortunately, nitazoxanide, the only drug with known efficacy, is only moderately effective for treatment of immunocompetent people, and it is equivalent to placebo in severely immunocompromised people. Cryptosporidiosis predominantly affects people in the developing world, and the high cost of de novo drug development is a major barrier to developing an effective treatment. Using a drug repurposing approach to address this economic barrier, the ultimate goal of this project is to develop an effective therapy for cryptosporidiosis The target product profile requires that the treatment be safe, low in cost, selectively toxic for Cryptosporidium at concentrations relevant within the small intestine and biliary tract, and capable of eliminating the parasite from patients in the absence of effective host immunity. Towards this end, preliminary data are presented documenting: 1) development and validation of a robust, cell-based, high-throughput screening (HTS) assay; 2) identification of FDA-approved drugs with selective anti-Cryptosporidium activity; and 3) an in vitro assay to compare the ability of different treatments to eliminate C. parvum from a cell-based tissue culture system. In aim 1, the abilities of the identified anti-Cryptosporidium drug leads to eliminate C. parvum will be determined in vitro, and then the drug leads will be tested in vivo using a model of cryptosporidiosis in severely immunocompromised mice. Synergistic drug combinations sometimes possess cidal antimicrobial activity (i.e., kill microbes rather than merely inhibit microbial growth) at achievable tissue concentrations despite static activity of each drug used alone, and, in some cases, drug combinations enable successful treatment of immunocompromised patients where either drug alone is ineffective. Therefore, in aim 2, combinatorial drug screens will be undertaken to identify drugs with synergistic anti-Cryptosporidium activity when used with nitazoxanide or the primary screening hits. As proof of concept, a screen was conducted in the presence of a sub-inhibitory concentration of nitazoxanide, which yielded five approved drugs with no anti-cryptosporidial activity when used alone that were strong C. parvum growth inhibitors in combination with low dose nitazoxanide. Synergy of promising drug combinations will be confirmed with checkerboard assays, and the most promising will be followed up in vitro and in vivo as in aim 1. Successful completion of these specific aims will result in identification of at least one FDA-approved drug or a combination of drugs that cures immunocompromised mice infected with C. parvum and is suitable for testing in human clinical trials.

描述(由申请人提供)：隐孢子虫病是由细胞内寄生虫微小隐孢子虫或人隐孢子虫引起的肠道感染，是美国水媒疫情引起的腹泻的主要原因，也是发展中国家儿童感染性腹泻的主要原因。这种感染是慢性的，对于免疫功能低下的患者来说往往是致命的，而隐孢子虫病导致艾滋病患者慢性腹泻的比例高达50%。不幸的是，硝唑尼特是唯一已知疗效的药物，对免疫功能正常的人只有中度疗效，对于免疫严重受损的人，它相当于安慰剂。隐孢子虫病主要影响发展中国家的人们，新药开发的高昂成本是开发有效治疗方法的主要障碍。利用药物再利用的方法来解决这一经济障碍，该项目的最终目标是开发一种治疗隐孢子虫病的有效方法。目标产品概况要求治疗是安全的、低成本的、对隐孢子虫具有选择性毒性的浓度在小肠和胆道内，并能够在缺乏有效宿主免疫的情况下从患者身上消除寄生虫。为此，提供了以下初步数据：1)开发和验证基于细胞的强健高通量筛选(HTS)试验；2)鉴定FDA批准的具有选择性抗隐孢子虫活性的药物；以及3)体外试验，比较不同处理方法从基于细胞的组织培养系统中消除微小隐孢子虫的能力。 在目标1中，将在体外测定已鉴定的抗隐孢子虫药物对微小隐孢子虫的清除能力，然后利用免疫功能严重受损的小鼠的隐孢子虫病模型在体内测试药物先导。尽管单独使用的每种药物具有静态活性，但协同药物组合有时在可达到的组织浓度下具有杀灭微生物的抗微生物活性(即，杀死微生物，而不仅仅是抑制微生物生长)，在某些情况下，药物组合能够成功地治疗免疫功能低下的患者，其中任何一种药物单独无效。因此，在目标2中，将进行组合药物筛选，以确定与硝唑尼特或初步筛选的HITS一起使用时具有协同抗隐孢子虫活性的药物。作为概念的证明，在存在亚抑制浓度的硝唑尼德的情况下进行了筛选，该浓度产生了5种批准的药物，当单独使用时没有抗隐孢子虫活性，这些药物是很强的微小隐孢子虫生长抑制剂，与低剂量的硝唑尼德联合使用。有希望的药物组合的协同作用将通过棋盘试验得到证实，最有希望的药物将像目标1一样在体外和体内进行跟踪。成功完成这些特定目标将导致至少识别一种FDA批准的药物或一种治疗免疫受损小鼠感染微小弧菌的药物的组合，并适合在人类临床试验中进行测试。

项目成果

A Proposed Target Product Profile and Developmental Cascade for New Cryptosporidiosis Treatments.

提议的目标产品概况和用于新的隐孢子虫病治疗的发育级联。

• DOI: 10.1371/journal.pntd.0003987
• 发表时间: 2015-10
• 期刊: PLoS neglected tropical diseases
• 影响因子: 3.8
• 作者: Huston CD;Spangenberg T;Burrows J;Willis P;Wells TN;van Voorhis W
• 通讯作者: van Voorhis W

A Novel Piperazine-Based Drug Lead for Cryptosporidiosis from the Medicines for Malaria Venture Open-Access Malaria Box.

• DOI: 10.1128/aac.01505-17
• 发表时间: 2018-04
• 期刊: Antimicrobial agents and chemotherapy
• 影响因子: 4.9
• 作者: Jumani RS;Bessoff K;Love MS;Miller P;Stebbins EE;Teixeira JE;Campbell MA;Meyers MJ;Zambriski JA;Nunez V;Woods AK;McNamara CW;Huston CD
• 通讯作者: Huston CD