Manufacture of aseptic, purified, cryopreserved Plasmodium vivax sporozoites

摘要 由间日疟原虫(PV)寄生虫引起的疟疾在发病率和 疾病的严重程度，而恶性疟排在第一位。然而，与PF不同的是，化疗 针对PV的预防措施不能防止由于重新激活PV而发生的复发，这是PV独有的 这种寄生虫在肝脏阶段持续睡眠的形式被称为催眠虫。伯喹是唯一获得许可的药物 它针对PV催眠者，但它会在G6PD患者中引起危及生命的急性溶血性贫血 缺乏症是最普遍的人类遗传疾病，在疟疾流行国家影响8%的人。 开发更好的药物或生产急需的疫苗的努力因无法 与PF不同，PV寄生虫在体外繁殖血液阶段。因此产生受感染的蚊子 受控人类疟疾感染(CHMI)作为评估抗PV药物和疫苗的手段是完全依赖的 蚊子以来自PV疟疾患者的新鲜、受PV感染的血液为食。加在一起，这些 瓶颈使得开发和测试针对PV疟疾的强有力的干预措施的任务更具挑战性 与PF相比。我们在我批准的建立和维护阶段取得了重大进展 无特定病原体(SPF)的菌落Saimiri boliviensis(SB)。以及包装无菌、纯化的疟原虫 间日疟原虫(PV)子孢子(SPZ)是在无菌蚊子中使用SPF SB和SPZ感染的血液产生的 在所有过程中和释放过程中符合无菌和释放标准。我们现在概述第二阶段的后续计划，以 制作大量符合cGMP的PvSPZ挑战，进行质量控制放行和稳定性 研究，准备临床试验方案，准备和提交研究新药(IND)申请 以及对人源化FRG KO huHEP小鼠的感染性研究，以及免疫原性和 以显性寄生虫血症为保护结果的小鼠模型的保护效果研究。该产品 本提案中概述的研究结果将被称为Sanaria®PvSPZ挑战赛，类似于PfSPZ 挑战将为更大的疟疾社区提供一个评估药物和疫苗有效性的工具 使用更安全的质量控制试剂对抗PV疟疾，该试剂的效力差异最小 不同的地段，在后勤管理上更可行，并且不受地理限制 应用程序，与使用蚊子叮咬的传统CHMI相比。它将代表着一个前所未有的里程碑 疫苗学领域，和疫苗制造，最重要的是它将形成一个强大的基础 预防小儿麻痹症疟疾的疫苗方法--PvSPZ 化学预防疫苗(PvSPZ-CVac)。

ABSTRACT Malaria caused by Plasmodium vivax (Pv) parasites is ranked second with respect to the incidence and severity of disease while Plasmodium falciparum (Pf) malaria is ranked first. However unlike Pf, chemo prophylactic measures against Pv do not prevent relapses, unique to Pv, that occur due to re-activation of persistent liver-stage sleeping forms of the parasites called hypnozoites. Primaquine is the only licensed drug that targets Pv hypnozoites, but it causes life threatening acute hemolytic anemia in patients with G6PD deficiency, the most prevalent human genetic disorder, affecting 8% of people in malaria-endemic nations. Efforts to develop better drugs or produce a much needed vaccine are further hampered by the inability to propagate blood stages of Pv parasites in vitro, unlike Pf. Therefore generating infected mosquitoes for controlled human malaria infection (CHMI) as a means to assess anti-Pv drugs and vaccines, is entirely reliant on feeding of mosquitoes on fresh, Pv-infected blood from patients with Pv malaria. Together, these bottlenecks make the task of developing and testing robust interventions against Pv malaria more challenging compared to Pf. We have made significant progress under a phase I grant toward establishing and maintaining a colony of specific pathogen free (SPF) Saimiri boliviensis (Sb). and vialing aseptic, purified Plasmodium vivax (Pv) sporozoites (SPZ) that were generated in aseptic mosquitoes using infected blood from SPF Sb and met asepticity and release criteria in all in process and for release. We now outline phase 2 follow-up plans to manufacture a lot of PvSPZ Challenge in compliance with cGMPs, conduct quality control release and stability studies, prepare a clinical trial protocol, and prepare and submit an Investigational New Drug (IND) application to the FDA along with an infectivity study in humanized FRG KO huHEP mice, and an immunogenicity and protective efficacy study in a mouse model with patent parasitemia as the protection outcome. The product resulting from studies outlined in this proposal will be called Sanaria® PvSPZ Challenge, and similar to PfSPZ Challenge will provide the larger malaria community with a tool to assess the efficacy of drugs and vaccines against Pv malaria with a safer quality-controlled reagent that exhibits minimal variability in potency between different lots, is logistically more feasible to administer, and is not subject to geographical limitations for application, compared to traditional CHMI using mosquito bites. It will represent an unprecedented milestone in the field of vaccinology, and vaccine manufacturing and most importantly it will form the basis of a powerful vaccine approach to preventing Pv malaria when administered with anti-malarial chemoprophylaxis, the PvSPZ chemoprophylaxis vaccine (PvSPZ-CVac).