Development of a thermostable rotavirus vaccine for mucosal delivery withoutneed for reconstitution - Phase II

项目总结/摘要 轮状病毒（RV）每年造成约50万人死于严重腹泻，其中大部分在非洲。 发展中国家的儿童。目前，只有两种RV疫苗可广泛使用，并通过 液体滴剂（直接或重构后）给6-14周龄的婴儿。两种疫苗都不稳定 在环境温度下，因此受到冷链的约束，以及由于其 液体成分。向婴儿注射液体的缺点是有可能将疫苗吐出， 增加了疫苗接种不足的风险。此外，除了在关键时期让婴儿不受RV的保护外， 在出生后的头几个月，仅在6周龄后接种疫苗的方案被发现会导致更高的 疫苗相关性肠套叠--一种潜在的致命性肠梗阻。此外，这些疫苗的成本 在最贫穷的国家，由于这些国家的发病率和负担最高， RV胃肠炎。因此，迫切需要开发一种成本有效的热稳定轮状病毒疫苗， 在新生儿时期的无液体给药。 国际医学基金会（IMF）拥有低成本液体RV疫苗RRV-TV的全球许可证， 设计了一种改进的新生儿给药方案，数据显示， 肠套叠该疫苗是作为公私合作项目开发的，已完成第二阶段 在加纳进行临床试验，并将在不久的将来向世卫组织申请向联合国机构供应的资格预审。 UST的专利蒸发防腐（PBV）稳定技术和生产技术 含有经PBV干燥的生物制剂的聚合物膜能够以干膜形式进行口腔疫苗递送。同相 在RV疫苗的研究中，UST已经证明聚合物膜中的PBV干燥疫苗保留了高活性， 37°C下长期稳定性≥2个月，25°C下长期稳定性5个月。这些技术的应用 由于疫苗原料价格低廉， 通过PBV和无制冷配送和储存，可以提高生产产量。最终 产品将是一种热稳定的RV疫苗，在粘膜粘附性可溶性聚合物膜中， 因此，本发明提供了一种用于口腔或舌下表面给药的方法，以向新生儿提供更简单、更准确的给药。 第二阶段项目的具体目标是：1）应用第一阶段制定的PBV方案 2）优化膜生产方案以掺入PBV RRV-TV疫苗 和抗酸剂，和3）使用仓鼠和大鼠在体外和体内证明膜的适用性和安全性， 以及在无菌仔猪模型中的体内疫苗免疫原性和对抗攻击的效力。长期 目的是产生含有热稳定RRV-TV轮状病毒的可溶性粘膜粘附聚合物膜 用于新生儿简单口腔粘膜递送的疫苗，其具有低的制造、储存和运输成本， 免疫原性、安全性和保护性。

PROJECT SUMMARY/ABSTRACT Rotavirus (RV) is responsible for an estimated 500,000 deaths each year from severe diarrhea, mostly in children in developing countries. Currently only two RV vaccines are broadly available, and are delivered by liquid drops (either directly or after reconstitution) to infants between 6-14 weeks of age. Both vaccines are labile at ambient temperatures and so bound by the cold chain, as well as being sensitive to freezing because of their liquid components. A drawback of liquid delivery to babies is the potential for spitting out the vaccine, which increases the risk of under-vaccination. Also, aside from leaving babies unprotected from RV during the crucial first months of life, the protocol of vaccinating only after 6 weeks old has been found to lead to greater rates of vaccine-associated intussusception – a potentially fatal bowel blockage. Furthermore, the cost of these vaccines is often prohibitively high for introduction in the poorest countries, which have the highest rates and burden of RV gastroenteritis. Thus there is an urgent need to develop a cost-effective thermostable rotavirus vaccine for liquid-free administration during the neonatal time period. International Medica Foundation (IMF) has world-wide license for a low-cost liquid RV vaccine, RRV-TV, and has designed an improved neonatal administration protocol which data indicates will reduce the rate of intussusception. This vaccine was developed as a public-private partnership project and has finished Phase II clinical trials in Ghana, and will seek WHO Prequalification for supply to UN agencies in the near future. UST’s patented Preservation by Vaporization (PBV) stabilization technology and techniques for producing polymeric films containing PBV-dried biologicals enable buccal vaccine delivery in the dry film format. In Phase I studies with RV vaccine, UST has proven that PBV-dried vaccine in polymeric film retains high activity and long-term stability for ≥2 months at 37°C and 5 months at 25°C. The application of these technologies for use with RRV-TV will decreased the cost of vaccine implementation due to the low-priced raw vaccine material, enhanced manufacturing yields possible with PBV, and refrigeration-free distribution and storage. The final product will be a thermostable RV vaccine in a mucoadhesive dissolvable polymeric film for liquid-free administration to the buccal or sublingual surfaces, to provide simpler, more accurate dosing to neonates. The specific objectives of this Phase II project are 1) Application of PBV protocols developed during Phase I to tetravalent RRV-TV vaccine 2) Optimization of film production protocols to incorporate PBV RRV-TV vaccine and antacids, and 3) demonstrate film suitability and safety in vitro as well as in vivo using hamsters and rats, and in vivo vaccine immunogenicity and efficacy against challenge in a gnotobiotic piglet model. The long-term goal is to generate a dissolvable mucoadhesive polymeric film that contains thermostable RRV-TV rotavirus vaccine for simple oral mucosal delivery to neonates which has low cost of manufacture, store and ship and is immunogenic, safe and protective.