Malaria Prevention

The purpose of this study is to demonstrate the feasibility, acceptability, and preliminary effectiveness of a focal mass drug administration program for household members of pregnant women to protect against malaria in pregnancy.

This Phase 1b study will assess the safety, tolerability and pharmacokinetics (PK, this measures the levels of study drug in the body) of a single injection of MMV371 in healthy adult and adolescent participants in Rwanda. MMV371 has been designed as a long acting injection (LAI). Protective efficacy (PE) will be assessed as an exploratory endpoint. Protective efficacy measures if participants are protected from becoming ill with malaria whilst the MMV371 is still present in their body. The study will enroll approximately 80 healthy male and female participants, aged 12 to 50 years. Before starting the study participants will be given a standard approved course of artemether lumifantrine (AL) to clear any malaria infection they have. Once the AL course has been completed the study drug will be given by injection in the muscle of the upper arm, the side of the thigh, or the hip. Three out of four participants will receive MMV371 and 1 in four participants will receive placebo. Placebo is a dummy medicine. All participants have an equal chance of being assigned to receive the injection in the upper arm, outer thigh or hip. Neither the participants nor the researchers treating the participants will know who received MMV371 or placebo until after the study is completed. Key study features include: * Study duration for each participant: up to 7 months * MMV371 or placebo given: a single intramuscular (IM) injection * Visit schedule: Participants will remain in-clinic on Days -1-2 (2 overnight stays), followed by 15 follow-up visits: Day 4, then weekly for 1 month, and subsequently every 2 weeks until the End-of-Study (EoS) visit at Week 24. These frequent visits are necessary to monitor safety, the levels of MMV371 in the body, and to perform malaria detection testing until EoS (Week 24).

Malaria is a major problem in western Kenya, particularly around Lake Victoria. Whilst current prevention methods like bed nets and vaccines help to reduce malaria burden, additional tools are needed to better protect communities from malaria. The investigators will test a new technology called LASER Guardian™, which are devices that release chemicals to keep mosquitoes away from homes. The investigators will conduct a large study involving 69 villages in western Kenya over two years. Each village will be randomly chosen to receive one of three approaches: the new LASER devices, indoor residual spraying with insecticide (a method already known to work), or the standard prevention methods currently used. All villages will continue to receive the usual malaria prevention tools provided by the Kenyan government, including bed nets and vaccines. In villages receiving LASER, the investigators will install 2-3 small device inside structures once a year for two years. In villages receiving IRS, the investigators will spray the inside walls of homes with insecticide once a year for two years. The investigators want to find out if the LASER devices can reduce malaria better than current methods alone, and whether they work as well as indoor spraying. To do this, the investigators will carry out surveys of the community every six months over two years (four rounds in total), testing about 4,485 children between ages 1 and 15 from approximately 3,450 households in each survey to see how many have malaria. The investigators will also work with local health clinics to track malaria cases, study mosquitoes to understand how the interventions affect them, talk with community members about their experiences, and calculate the costs of these different approaches. This study will help us understand whether LASER tool can effectively protecting against malaria in Kenya and other African countries where malaria is common.

This clinical study will evaluate an investigational malaria vaccine called PvCS/Montanide ISA-51 to determine whether it is safe and whether it can protect adults from infection with Plasmodium vivax, one of the main parasites that causes malaria. P. vivax malaria is common in tropical regions, including Colombia, and can lead to recurrent fever, anemia, and prolonged illness. Currently, no licensed vaccine effectively prevents P. vivax infection. The investigational vaccine (PvCS) contains synthetic peptides derived from the circumsporozoite (CS) protein located on the surface of P. vivax sporozoites. The vaccine is formulated with the adjuvant Montanide ISA-51 to enhance the immune response. This study aims to assess the safety of the PvCS/Montanide ISA-51 formulation and to determine whether it can prevent malaria after controlled exposure to the parasite. This is a Phase IIa/b, randomized, double-blind, placebo-controlled clinical trial conducted by the Malaria Vaccine and Drug Development Center (MVDC/CIV) in collaboration with ASOCLINIC IPS and the Pacific Health Institute (INSALPA) in Quibdó, Chocó, Colombia. A total of 72 healthy adults aged 18-50 years from malaria-endemic areas will participate. Participants will be randomly assigned in a 2:1 ratio to receive either the PvCS/Montanide ISA-51 vaccine or a placebo. The study product will be administered by intramuscular injection at months 0, 2, and 4. After each vaccination, participants will be monitored for side effects and provide blood samples to measure immune responses, including antibody levels and T-cell activity. Approximately one month after the third vaccination, participants will undergo a controlled human malaria infection (CHMI), during which they will be exposed to P. vivax through the bite of infected mosquitoes under strict medical supervision. Following exposure, participants will be monitored daily using blood tests to detect malaria at the earliest stage. If malaria parasites are detected-or if 21 days pass without infection-participants will receive prompt, effective antimalarial treatment based on Colombian national guidelines. All participants will continue to be followed for up to 12 months after the challenge to ensure safety and assess long-term outcomes. Primary goals of the study include: Determining whether the PvCS/Montanide ISA-51 vaccine prevents P. vivax infection after CHMI. Measuring the time between exposure and first detection of parasites (pre-patent period). Evaluating the safety and tolerability of the vaccine. Secondary goals include: Measuring immune responses generated by the vaccine. Exploring relationships between immune responses and protection from infection. The total duration of the study is expected to be approximately 30 months, including recruitment, immunizations, challenge procedures, and follow-up. Results will help determine whether this vaccine can safely protect adults against P. vivax malaria and guide planning for future larger-scale vaccine trials in endemic populations.