Durability of Protection After Single Immunisation With Genetically Attenuated Plasmodium Falciparum ∆mei2 (GA2) Sporozoites - a Follow-up, Controlled Human Malaria Rechallenge Study
试验速览
- 阶段
- 2 期
- 状态
- 招募中
- 发起方
- 入组人数
- 14
- 试验地点
- 1
- 主要终点
- Protective efficacy
研究概览
简要总结
This study will assess the durability of protection of a single immunisation with the Genetically Attenuated Parasite 2 (GA2) against controlled human malaria infection by rechallenging previously immunised and protected participants from the CoGA study (NCT05468606)
详细描述
This will be a non-randomised, open-label, controlled human malaria infection study that will consist of two study arms: the rechallenge group and infection controls. The rechallenge group consists of study participants from the CoGA study (phase I) who received single immunisation with GA2 and were protected during subsequent CHMI, while infection controls are newly recruited, malaria-naïve study participants. All participants will undergo CHMI through the bites of 5 mosquitos infected with wild-type 3D7 sporozoites. From day 6 to 21 after CHMI, participants will be followed daily on an out-patient basis to determine parasite loads detected by a quantitative polymerase chain reaction (qPCR). As soon as parasitaemia is detected (cut-off >100p/mL), or at the latest 28 days after CHMI, participants will be treated with a curative regimen of antimalarials.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- None
入排标准
- 年龄范围
- 18 years 至 64 years（18-64 Years）
- 接受健康志愿者
- 是
入选标准
- 未提供
排除标准
- 未提供
研究组 & 干预措施
Rechallenge group
Previous CoGA phase 1 study participants who were immunised with GA2 and who did not develop blood-stage malaria during CHMI (protected)
干预措施: CHMI with 3D7 malaria (Biological)
Infection control group
Malaria-naïve participants who have not been previously vaccinated with GA2
干预措施: CHMI with 3D7 malaria (Biological)
结局指标
主要结局
Protective efficacy
时间窗: Moment of CHMI to antimalarial treatment (28 days post CHMI)
Proportion of participants that do not develop parasitaemia (qPCR \>100p/mL) (sterile protection) after CHMI (re)challenge in participants with prior, single GA2 immunisation compared to infection controls.
Time to parasitaemia
时间窗: Moment of CHMI to antimalarial treatment (28 days post CHMI)
The time to parasitaemia (qPCR \>100 p/mL) (prepatent period) after CHMI (re)challenge between participants with prior, single GA2 immunisation and infection controls.
次要结局
- Cellular immune responses after homologous CHMI rechallenge(Moment of CHMI up to182 days post CHMI)
- Humoral immune responses after homologous CHMI rechallenge(Moment of CHMI up to182 days post CHMI)
研究者
Meta Roestenberg
Scientific
Leids Universitair Medisch Centrum (LUMC)