Clinical Investigation Study to Evaluate the Consistency and Reproducibility of Two Consecutive Mosquito Feeding Assays in Adults With Varying Plasmodium Falciparum Gametocyte Densities
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 42
- 试验地点
- 1
- 主要终点
- Oocyst Prevalence
研究概览
简要总结
The proposed trial design has been developed to assess the consistency and reproducibility of two consecutive direct skin feeding assays (DSFA) at 24-hour interval.
详细描述
The proposed trial design has been developed to assess the consistency and reproducibility of two consecutive direct skin feeding assays (DSFA) at 24-hour interval. The results will determine the type of pivotal trial design for a follow-on Phase 2b trial whose objective is to bridge the standard membrane feeding assay (SMFA) to the direct skin feeding assay (DSFA) and direct membrane feeding assay (DMFA) using a monoclonal antibody intervention, TB31F monoclonal antibody (mAb), which interrupts transmission from human to mosquito. The results from this experimental medicine study will inform whether the preferred "Before-After" trial design in which each human volunteer serves as their own internal control can be utilized for a follow-on Phase 2b trial.
研究设计
- 研究类型
- Observational
- 观察模型
- Other
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 55 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Provision of signed or thumb printed and dated informed consent form
- •Stated willingness to comply with all study procedures and availability for the duration of the study
- •Male or female aged between 18 years and 55 years inclusive.
- •Resident within the study area
- •In good general health as evidenced by medical history and clinical examination before entering the study Ability to take oral Coartem and low-dose primaquine anti-malarials upon conclusion of day 2 (2nd direct skin feed) and be willing to adhere to the medication regimen
- •For females, she must be of non-childbearing potential or use appropriate measures to prevent pregnancy for 30 days after receiving Coartem and primaquine. Non-childbearing potential means she is surgically sterilized or at least one year post-menopausal. Appropriate measures to prevent pregnancy include abstinence or adequate contraceptive precautions (i.e. intrauterine contraceptive device; oral contraceptives; diaphragm or condom in combination with contraceptive jelly, cream or foam; Norplant or Depo-Provera).
- •For males, he must be willing to ensure that he does not get his partner(s) pregnant for at least 3 months after treatment with primaquine. Appropriate measures to prevent pregnancy include abstinence or adequate contraceptive precautions in either the participant or the partner.
- •Positive for P. falciparum gametocytes as measured by polymerase chain reaction (PCR) with cycle threshold (cT) value < 31.
排除标准
- •Presence of any signs or symptoms of malaria
- •Presence of contraindications to administration of Coartem and primaquine as indicated in the respective drug package inserts
- •History of severe allergic reactions to mosquito bites (other than pruritus and local swelling)
- •Pregnant (i.e. a positive pregnancy test)
- •Current or recent (within the preceding 2 weeks) use of antimalarial treatment
- •Current participation in a malaria vaccine study
- •Any other findings that the investigator feels would increase the risk of having an adverse outcome from participation in the trial.
研究组 & 干预措施
Study Volunteers
Participants provided a blood sample on Day 1 for DMFA testing and then participated in the mosquito feeding assay. On Day 2 participants underwent a second DMFA and DSFA assay (within 24 hours of the first assays).
Upon completion of Day 2 DSFA participants will receive one dose of primaquine and the first dose of a 3-day regiment of artemether/lumefantrine.
干预措施: Direct Skin Feeding Assay (DSFA) (Other)
Study Volunteers
Participants provided a blood sample on Day 1 for DMFA testing and then participated in the mosquito feeding assay. On Day 2 participants underwent a second DMFA and DSFA assay (within 24 hours of the first assays).
Upon completion of Day 2 DSFA participants will receive one dose of primaquine and the first dose of a 3-day regiment of artemether/lumefantrine.
干预措施: Primaquine (Drug)
Study Volunteers
Participants provided a blood sample on Day 1 for DMFA testing and then participated in the mosquito feeding assay. On Day 2 participants underwent a second DMFA and DSFA assay (within 24 hours of the first assays).
Upon completion of Day 2 DSFA participants will receive one dose of primaquine and the first dose of a 3-day regiment of artemether/lumefantrine.
干预措施: Artemether/Lumefantrine (Drug)
结局指标
主要结局
Oocyst Prevalence
时间窗: Feeding assays were performed on Day 1 and Day 2; Oocyst prevalence in surviving mosquitoes was assessed 9 days after feeding (Days 9 and 10).
Participants underwent feeding assays on two days, 24 hours apart (day 1 and Day 2). After feeding, mosquitoes were maintained in locked environmental chambers for 9 days to allow oocyst development. An oocyst is a structure that develops on the outer wall of the infected mosquito's stomach that contains developing sporozoites. Nine days after feeding mosquito midguts were dissected, stained with 1% mercurochrome and examined by optical microscopy. The number of oocysts in each midgut were recorded. Oocyst prevalence is defined as the percentage of mosquitoes in a cup with at least one oocyst detected in the mid-gut among the surviving mosquitoes (in the same cup) that underwent the feeding assays.
次要结局
- Oocyst Density(Feeding assays were performed on Day 1 and Day 2; Oocyst density in surviving mosquitos was assessed 9 days after feeding (Days 9 and 10).)
- Sporozoite Prevalence(Feeding assays were performed on Day 1 and Day 2; Sporozoite prevalence in surviving mosquitoes was assessed 14 days after feeding (Days 14 and 15).)
- Sporozoite Density(Day 1 and Day 2)