There are about 94 clinical studies being (or have been) conducted in Gambia. The country of the clinical trial is determined by the location of where the clinical research is being studied. Most studies are often held in multiple locations & countries.
Controlled human malaria infection (CHMI) is an important tool for the assessment of the efficacy of novel malaria vaccines and drugs prior to field trials. CHMI also allows for the evaluation of immunity to malaria and parasite growth rates in vivo and thus allows for the assessment of the natural acquisition and loss of malaria immunity. This may be particularly useful in individuals from endemic areas with changing levels of exposure and immunity to malaria. Thus, CHMI in individuals with prior exposure to malaria could be a valuable tool to accelerate malaria vaccine development and inform malaria control programs of changing immunity levels and related disease presentations. In this trial, the investigators intend to study the effect of pre-exposure to Plasmodium falciparum (Pf) on parasite kinetics, clinical symptoms and immunity after CHMI by PfSPZ Challenge in Gambian adults. Based on a well-defined sero-profile representing the extremes of current malaria exposure in The Gambia, two cohorts will be identified to study the impact of naturally acquired immunity on susceptibility for a Controlled Human Malaria Infection.
This micronutrient supplementation study is a 3-arm randomized controlled trial, unblinded, with 125 women per arm. Non-pregnant, non-lactating healthy women of reproductive age in West Kiang, The Gambia, will be randomized to 12 weeks of daily supplementation of either a) novel micronutrient supplement, b) a United Nations International Multiple Micronutrient Preparation (UNIMMAP) tablet or c) no intervention (control). The novel micronutrient supplement is a drink powder providing 800 µg folic acid, 5.2 µg cyanocobalamin (B12), 2.8 mg Riboflavin-5'-phosphate (B2), and 4g trimethylglycine (betaine). UNIMMAP contains 15 micronutrients at the Recommended Daily Allowance level. The aim is to test the effectiveness of the supplements on correcting micronutrient deficiencies in the dry season and to reduce homocysteine levels. The hypothesis is that the new drink powder will be the most effective supplement, causing a reduction in 1 µmol/L compared to the control group after supplementation. The supplements will be supplied to participants on a daily basis by Community-based Birth Attendants (CBCs). The CBCs will observe consumption of the supplement. The novel micronutrient supplement will be provided in powder form with instructions to dissolve one sachet in a cup of 200ml water. UNIMMAP will be provided in capsule form to be taken with water. Women will provide one 10ml fasted venous blood sample at baseline and another after 6 and 12 weeks of supplementation. At each time point they will also have their blood pressure and anthropometry assessed and provide a urine pregnancy test. Correcting micronutrient deficiencies is extremely important for the long-term health of women, and in particular around the time of conception and throughout pregnancy since micronutrients are needed for the proper physical and cognitive development of the baby. Certain micronutrients are required for adding a methyl group to places on DNA ('DNA methylation'). The pattern of these methyl groups can help determine whether a gene is switched on or off. Correct functioning of DNA methylation processes is therefore of critical importance for fetal development. High levels of homocysteine can impede DNA methylation, therefore supplements that reduce homocysteine may not only be beneficial for the mother but also for the developing child. The most effective supplement in this trial will be considered for testing in larger pregnancy trials.
The motivation for this study was produced from our preliminary data, which showed that during the first 96 hours of life a full-term neonate will actively reduce the overall serum iron concentration of their blood and the transferrin saturation decreases rapidly from 45% in cord blood to ~20% by six hours post-delivery. The Investigators hypothesise that this active sequestration of iron, which results in hypoferremia, is done in an effort to limit susceptibility to infection, a process referred to as nutritional immunity. Currently, little is known about iron regulation and iron homeostasis during the first week of life and even less is known about the comparisons of nutritional immunity between full term, preterm and low birth weight neonates. Additionally, limited research has been conducted on the impact of these processes on bacterial pathogens. In an effort to study the neonatal nutritional immunity and its role in neonatal susceptibility to infection, The investigator will conduct an observational study in full-term, preterm and low birth weight vaginally-delivered neonates born at Serrekunda General Hospital, The Gambia. The investigators will fully characterise and quantify nutritional immunity during the early neonatal period and the investogators will assess how this impacts bacterial growth. Study sensitisation will occur at the antenatal clinic, during the mother's second trimester of pregnancy. Mothers will be consented and enrolled at delivery. Blood samples will be collected once from the umbilical cord and at serial time points from the neonates over the first week of life.
Title: Evaluation of host biomarker-based point-of-care tests for targeted screening for active TB (Screen TB) Introduction: Tuberculosis (TB) places severe pressure on health care services of the developing world. Despite the introduction of the highly sensitive and specific GeneXpert MTB/RIF (GeneXpert) test [1] with a potential turn-around time of two hours, many people in high TB prevalence areas still do not have access to efficient TB diagnostic services due to logistical constraints in these settings. A cost effective, rapid, point-of-care screening test with high sensitivity would identify people with a high likelihood for active TB and would prioritize them for testing with more expensive, technically or logistically demanding assays including GeneXpert or liquid culture, facilitating cost-effective diagnostic work-up in resource-limited settings. A serum cytokine signature for active TB disease, discovered in the AE-TBC project, with a sensitivity of 89% (CI 78 - 95%) and specificity of 76% (CI 68 - 83%), will be optimised and utilized in a point-of-care format (TransDot) to rapidly test for TB disease in symptomatic people. Hypothesis: The TransDot test will achieve a sensitivity of > 90% for TB disease, in a training set of people suspected of having TB disease, and be validated (achieve similarly high sensitivity) subsequently in a prospective test set of people suspected of having TB disease, when compared to a composite gold standard of sputum culture, smear, GeneXpert, chest X-ray, TB symptoms and TB treatment response. Objectives: The overall objective of the study is to incorporate a six-marker serum signature into a multiplex UCP-LFA format, referred to as TransDot, for finger-prick blood testing. The end point of the study is the accuracy (sensitivity and specificity) of the UCP-LFA TransDot test on finger-prick blood for active TB and will be prospectively compared against gold standard composite diagnostic criteria (GeneXpert, MGIT culture, TB sputum smear, CXR, TB symptom screen and response to TB treatment). Primary: The primary outcome of interest will be accuracy, sensitivity and specificity of the TransDot finger-prick test when compared with the composite gold standard tests.
Anaemia continues to be one of the most common health problems affecting children and pregnant women in low-income countries. Nutritional iron deficiency is believed to be the main driver of anaemia, so mass iron supplementation and food fortification programs have been recommended by most public health organizations. However, these interventions are frequently ineffective and new strategies are desperately needed. Both anaemia and iron absorption are influenced by multiple factors, including nutritional status, infection, low grade inflammation and host genetics. The discovery of hepcidin, the master regulator of iron absorption and regulation has opened new avenues for investigation. Genome-wide association studies have identified several single nucleotide polymorphisms (SNPs) within hepcidin regulatory genes that are associated with altered iron status both in African populations. The study aims to investigate the impact of genetic alterations in hepcidin regulation on oral iron absorption. A recall-by-genotype study will be conducted using an existing database of pre-genotype individuals in rural Gambia (West Kiang). This database comprise of data on >3000 Gambians, with Illumina HumanExome array data on 80K directly genotyped putative functional variants as well as imputation data on 20M variants.
The primary purpose of the proposed research is to establish Reference Values (RVs) for micronutrients (MN) and macronutrients in human milk. The investigators' research to date has revealed highly variable milk MN concentrations among populations, and very low values in some low income countries (LICs) likely caused by poor maternal status and/or diet but RVs are needed to interpret these values. During the past year the investigators conducted a review of human milk nutrient composition, and formed a Technical Advisory Group (TAG) which developed the current proposal. Here, the investigators are conducting a longitudinal project on well-nourished women and infants. The Mothers, Infants and Lactation Quality (MILQ) study is a multi-center cohort project, investigating breast milk nutrient composition in well-nourished women across the first 8.5 months of lactation in four different populations. The countries involved are Denmark, Brazil, Bangladesh and The Gambia. Exclusive breastfeeding is an eligibility criterion up until the second post-partum study visit (between 1 - 3.4 months postpartum), with the exception of the first week after delivery. Other data collected on mothers and infants, including maternal and infant nutrient intake and status, morbidity, milk volume, and infant development, will inform interpretation and support application of the results. While the priority is to develop RVs for MN, other analyses will include human milk oligosaccharides (HMOs) and proteins, and free amino acids (FAA) in infant plasma. Thus, with the samples obtained the investigators will perform (a) laboratory analyses of milk, plasma and urine nutrients to construct RVs for global application, (b) analyses of HMOs and proteins in milk, and (c) metabolomic analysis of FAA and other metabolites in infant plasma. By request of the Bill and Melinda Gates Foundation (BMGF), colostrum and fecal microbiota samples will also be collected and stored for later analyses.
This is an observational cohort study. Pulmonary tuberculosis (TB) patients will be enrolled at the time of TB diagnosis and prospectively followed for at least two years after TB-treatment initiation with optional prolonged follow-up. Study visits will be performed in the study clinics or if necessary at the participant's home at pre-defined time points after TB treatment initiation. Clinical assessments, biological sample collections and collection of socio-economic data will be performed according to the pre-defined schedule of events.
Infection is the most common cause of death in early life, especially for newborns and can be reduced by immunization but insufficient knowledge of how vaccines protect the very young limits their optimal use. To gain insight into how vaccines induce protection of the most vulnerable, this National Institutes of Health (NIH)/National Institute of Allergy & Infectious Diseases (NIAID)-funded Human Immunology Project Consortium (HIPC) study, based at Boston Children's Hospital and conducted by the Expanded Program on Immunization Consortium (EPIC), employs two novel approaches studying newborn responses to hepatitis B vaccine (HBV): (a) systems biology that uses technologies which comprehensively measure global changes in molecules such as transcriptomics (RNA) and proteomics (proteins), as well as cell composition of the blood and (b) use of human newborn blood components, collected prior to immunization, to model vaccine responses in vitro (outside the body). Characterizing vaccine-induced molecular patterns ("signatures") that correspond to vaccine-mediated protection will accelerate development and optimization of vaccines against early life infections of major global health importance.
Though maternal and neonatal health are high priority areas for international development, maternal and neonatal mortality remain unacceptably high. Worldwide there are 1 million maternal and 4 million neonatal deaths every year and half of them occur in sub-Saharan Africa. Post-partum and neonatal severe bacterial infections, namely sepsis, are leading causes of maternal and neonatal deaths in sub-Saharan Africa. Newborns can be infected during labour - when passing through the birth canal - and also during the first days/weeks of life, as a consequence of the close physical contact with the mother, when the latter carriers bacteria. As the mother is an important source of bacterial transmission to the newborn, treating mothers with antibiotics during labour should decrease their bacterial carriage and therefore lower transmission to the newborn. As carriage is a necessary step towards severe disease, this intervention should in turn result in the lower occurrence of severe bacterial disease and mortality during the neonatal period. In many high-income countries, pregnant women are screened during pregnancy for vaginal carriage of Group B Streptococcus, the bacteria responsible for the vast majority of neonatal sepsis in the developed world. If women are carriers, they are treated with intravenous antibiotics during labour to decrease the risk of severe disease to their off-spring. Although this intervention has been successful in developed countries, infrastructure and resource limitations in regions like sub-Saharan Africa prevent both screening and use of intravenous antibiotics. Also, in Africa several bacterial pathogens are responsible for neonatal sepsis and the antibiotics needed in the continent should cover a wider number of bacteria; and ideally cover also bacteria responsible for severe post-partum disease in the mother. We will conduct a large trial in West Africa, The Gambia and Burkina Faso, with the main objective of determining if a single dose of an oral antibiotic given to women during labour decreases newborn mortality. The trial will also assess the effect of the antibiotic on lowering newborns and maternal hospitalization during the first week's post-partum. We have selected an antibiotic (azithromycin) that in sub-Saharan Africa has already been used for elimination of other prevalent diseases such as trachoma. This antibiotic is safe, requires a single oral administration, has no special storage requirements and has the potential to eliminate most of the bacteria commonly causing severe disease in newborns and post-partum women in the continent. Very important this antibiotic is not widely used in clinical care in the continent, and therefore, any temporal increase of resistance induced by the intervention should not have implications on current treatment guidelines. Before going to the large trial proposed here (12,000 women to be recruited), we have generated robust preliminary data on the effect of the intervention in a proof-of-concept trial conducted in The Gambia (829 women and their offspring recruited). We found that in fact, babies born from mothers who had taken this antibiotic during labour were less likely to carry bacteria that can potentially cause severe disease. These babies were also three times less likely to have bacterial skin infections or umbilical infections, both highly common among African newborns. Besides, fever or mastitis (again both very common in the region) during the post-partum period were four times lower among mothers who had taken the antibiotic during labour. Such trial confirmed our hypothesis of impact on bacterial transmission but it was too small to assess the effect of the antibiotic on mortality and hospitalizations. The preliminary trial also showed that women from the azithromycin group were less likely to need antibiotics for treatment infections during the puerperal period, decreasing then the pressure on the scarcity of antibiotics available in the continent. The advantages of our approach are its simplicity, low cost and the possibility of protecting both mothers and babies with the same intervention.
This study will examine the consistency of 3 batches of the Pneumosil vaccine by looking at the immune response in infants. In addition, the study will compare the immunogenicity of the Pneumosil vaccine to another WHO-prequalified vaccine, Synflorix.