Clinical Research Directory

Safety, Tolerability and Efficacy of PfSPZ-LARC2 Vaccine Against CHMI in Malaria-Naïve Adults

This is a randomized, double-blind, placebo-controlled Phase 1 trial of Plasmodium falciparum (Pf) sporozoite (SPZ) late-arresting replication-competent (LARC) malaria vaccine (PfSPZ-LARC2 Vaccine) administered to healthy, malaria-naive study participants in Germany by direct venous inoculation (DVI) to determine safety, tolerability, and vaccine efficacy (VE) against controlled human malaria infection (CHMI). PfSPZ-LARC2 Vaccine contains a deletion of two genes, the Mei2 and LINUP genes, and undergoes developmental arrest in the late liver stages without releasing merozoites into the blood stream (blood stage parasites). The primary objective of the study is to assess the safety and tolerability of administration of PfSPZ-LARC2 Vaccine, with special attention to the adequacy of attenuation, in the intention-to-treat (ITT) population.

Safety and PK of MMV371 LAI in Healthy Adults and Adolescents in Rwanda

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).

Age De-escalation Safety Trial of PfSPZ-LARC2 Vaccine in Burkina Faso

This is a first-in-humans randomized, double-blind, placebo-controlled, age de-escalation Phase 1 trial of Plasmodium falciparum (Pf) late liver stage-arresting replication-competent (LARC) sporozoite (SPZ) malaria vaccine (Sanaria® PfSPZ-LARC2 Vaccine) administered to healthy, malaria-exposed adults and children by direct venous inoculation (DVI) to determine safety, tolerability, and immunogenicity. The PfSPZ comprising PfSPZ-LARC2 Vaccine contain a double gene deletion, of the Mei2 and LINUP genes. As a result, they undergo developmental arrest in the late liver stages without releasing merozoites into the blood stream (no blood stage parasites are produced, either asexual or sexual). Because Pf parasites with the LARC phenotype replicate in the liver before disintegrating, they amplify and diversify parasite protein expression and are expected to be a potent immunogen to induce anti-malarial immunity, equaling or exceeding the potency and efficacy of the replication-competent chemo-attenuated Sanaria® PfSPZ-CVac (chloroquine). Because the parasites are intrinsically attenuated, they are also expected to be safe and well tolerated, similar to radiation-attenuated Sanaria® PfSPZ Vaccine and to the single-gene(Mei2)-deleted GA2 parasites (also LARC phenotype) tested at the Leiden University Medical Center (LUMC), which, like PfSPZ-LARC2 Vaccine, disintegrate after replicating in the liver. PfSPZ-LARC2 Vaccine thus avoids the safety concerns associated with PfSPZ-CVac, which uses fully infectious, non-attenuated parasites to achieve replication and depends on co-administered chloroquine for attenuation. In summary, the genetically attenuated PfSPZ-LARC2 Vaccine should combine the best-in-class immunogenic potency and protective efficacy of PfSPZ-CVac (chloroquine) with the excellent safety and tolerability of intrinsically attenuated PfSPZ Vaccine and GA2 vaccine. This trial is designed to test the hypotheses that: 1. The vaccine is safe and well tolerated in each age group. 2. The true rate of breakthrough blood stage infection (or other concerning adverse events) is less than about 5%, with an 95% confidence level (this will be the level of confidence that there are no breakthroughs if no breakthroughs occur in the 50 participants receiving PfSPZ-LARC2 Vaccine).

Serological Testing and Treatment for Plasmodium Vivax Malaria: a Trial in Ethiopia and Madagascar

The resilience of P. vivax to malaria elimination efforts is due to its ability to form dormant liver stages (hypnozoites) that reactivate weeks to months after the initial infection causing recurrent episodes of malaria (relapses) and ongoing parasite transmission. Relapses account for a majority of recurrent infections and clinical cases of P. vivax malaria, and therefore have a significant effect on morbidity at the individual level. With current technology, it is not possible to directly measure hypnozoite biomarkers. Rather than directly detecting hypnozoites, our team developed an indirect approach by measuring antibodies induced by the primary blood-stage infection. Antibodies to different blood-stage antigens decay at different rates. Measuring antibodies to a carefully selected panel of P. vivax antigens can aid to identify individuals who have been infected within the previous 9 months (approximately the lifespan of hypnozoites). A serological test based on selected P. vivax antigens can detect recent exposure and predict future relapses. Coupling this test with a safe and efficacious primaquine treatment regimen, results in a population-based intervention to target the hypnozoite reservoir. This intervention is referred to as Plasmodium vivax Serological Testing and Treatment (PvSeroTAT). PvSTATEM is a cluster randomised trial in Madagascar and Ethiopia. This study will provide insights into the feasibility, acceptability, and efficacy of the PvSeroTAT approach. In this study, individuals, randomised by clusters, will be tested for the presence of serological markers of a recent P. vivax infection, followed by a targeted drug treatment intervention aimed at killing P. vivax hypnozoites.

Assessing the Feasibility of Combining Dihydroartemisinin Piperaquine and Primaquine for Malaria Mass Drug Administration in High Endemic Communities in the Eastern Region of Ghana

Previous malaria control studies in Ghana have shown that community-wide approaches can substantially reduce malaria infections. In a mass testing, treatment and tracking (MTTT) study, more than 75% of people in target communities were reached, leading to a 24% reduction in asymptomatic malaria after one year. However, rapid diagnostic tests (RDTs) can miss very low-level infections, meaning some infected individuals are not treated and can continue to spread malaria. A pilot malaria mass drug administration (MDA) study using artemether-lumefantrine (AL) in the Eastern Region of Ghana showed a very large reduction (over 95%) in parasite carriage after repeated rounds of treatment. Despite this success, malaria infections later fluctuated, possibly because some parasites remained in mosquitoes and because mature gametocytes-the parasite stage responsible for transmission-are not fully eliminated by standard malaria medicines. To better interrupt malaria transmission, this study will use MDA with dihydroartemisinin-piperaquine (DHAP) combined with a single low dose of primaquine (PQ), which targets these transmission stages. The intervention will be given to the whole community every two months (six times per year) and compared with the current standard malaria control measures. The study will examine whether this approach reduces malaria parasite carriage, whether malaria returns after treatment stops, and whether repeated MDA affects malaria drug resistance markers in the population. This two-year implementation research will generate practical evidence to guide national malaria policy in Ghana and inform the potential use of MDA in other malaria-endemic African countries.

IGHID 12334 - After the Flood: Optimal Strategies to Prevent Malaria Epidemics Caused by Severe Flooding

The purpose of this study is to test different ways to prevent malaria infections after flooding. To accomplish this, the investigators will assign villages to different control strategies and measure the number of malaria infections in each of the villages. Residents of all villages will receive new bed nets, but in some villages, residents will be provided with a monthly medication Dihydroartemisinin-piperaquine (DP) (a drug that is approved by the World Health Organization (WHO) and regulatory authorities and widely used in Africa for Malaria treatment. This drug is not approved by Food and Drug Administration (FDA) because it is not used in the US,) to prevent malaria, while others will also receive a treatment that can be placed into pools of water around the home to prevent mosquitoes from breeding there. The investigators will monitor the participant and their household members for mosquitoes and malaria over a period of 12 months after the flooding This study is important because, similar approaches could be used to prevent malaria after floods, which is occurring more frequently.

Experimental Malaria Infection of Healthy Malaria-Naive Adults by Mosquito Bite With the Genetically Modified Plasmodium Falciparum NF54/iGP3 GAP

The goal of this clinical trial is to learn if the genetically-modified malaria parasite NF54/iGP3 will safely infect humans with malaria. The investigators will also determine how the parasite grows in humans, and the effect of anti-malarial drugs. Researchers will use a controlled human malaria infection (CHMI) model to infect participants with malaria to observe the development of the disease, collect malaria-infected blood, and then treat the participants to cure the malaria infection. The collected malaria-infected blood will be used to create a frozen stock of malaria parasites for use in future research.