Clinical Investigation Study to Evaluate the Consistency and Reproducibility of Two Consecutive Mosquito Feeding Assays

PATH

Status: Completed

Conditions: Malaria

Treatments: Drug: Primaquine; Drug: Artemether/Lumefantrine; Other: Direct Skin Feeding Assay (DSFA)

Study type: Observational

Funder types: Other; Other U.S. Federal agency

Identifiers

NCT04666350

CVIA 085 -- Phase 0

Details and patient eligibility

About

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.

Full description

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.

Enrollment: 42 patients

Sex: All

Ages: 18 to 55 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• 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.

Exclusion criteria

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.

Trial design

42 participants in 1 patient group

Study Volunteers

Description:

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.

Treatment:

Drug: Primaquine

Drug: Artemether/Lumefantrine

Other: Direct Skin Feeding Assay (DSFA)