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.
Primary endpoints - Incidence of symptomatic and asymptomatic infection with SARS-CoV-2 and other respiratory viruses as determined by molecular (e.g. PCR) and serological testing - Associations between the magnitude and quality of mucosal and serum antibody responses to SARSCoV- 2 and protection from infection with SARS-CoV-2 - Associations between the magnitude and quality of T cell responses to SARS-CoV-2 and protection from infection with SARS-CoV-2 Secondary endpoints - Secondary attack rate and household cumulative infection rate with SARS-CoV-2, influenza, RSV, and other respiratory viruses - Seroincidence and seroprevalence of SARS-CoV-2 a determined by binding antibodies to SARS-CoV-2 spike and nucleocapsid - Presence of risk factors for symptomatic and asymptomatic infection with respiratory viruses - Antibody and T cell kinetics of SARS-CoV-2 following infection - Associations between the magnitude and quality of antibody and T cell responses to seasonal coronaviruses and protection from infection with SARS-CoV-2 - Associations between infection with non-SARS-CoV-2 respiratory viruses and protection from infection with SARS-CoV-2 - Associations between upregulation of gene expression in the mucosa, including interferon stimulated genes (ISGs), and protection from infection with SARS-CoV-2
The purpose of this study is to conduct a multi-country, multi-site, epidemiologic study designed to assess the proportion of interferon gamma release assay (IGRA) positivity, at site level, and to build capacity to conduct a future TB vaccine efficacy study.
A randomized, observer-blind non-inferiority trial to evaluate alternative human papillomavirus (HPV) vaccination schedules in young females in West Africa.
This study will assess the efficacy of Pyramax administered for three-day, two-day or one day, in clearing a P. falciparum infection in asymptomatic carriers. .
The World Health Organization (WHO) recommends that infants receive a single dose of the meningococcal serogroup A-tetanus toxoid conjugate vaccine, MenAfriVac, when they reach at least 9 months of age. However, this leaves a window of susceptibility in early life when the incidence of invasive serogroup A disease, and the case fatality rate for the condition is at its highest. This study will investigate the potential role of administering the vaccine to expectant mothers at the start of the third trimester of pregnancy in order to protect their subsequent borne infants. Antibody transfer to the newborn and subsequent antibody decay will be measured. The level of protection against neonatal tetanus provided by the tetanus toxoid component of the vaccine, when compared to the routine dose of tetanus administered in pregnancy will also be assessed. As a separate exploratory study, the follow-up of the cohort planned will also be used to investigate the effects that the development of the gastrointestinal microbiome, and any perturbations in the microbiome caused by antibiotic use, have on immune development and vaccine immunogenicity over the first 10 months of life.
Currently, there are two types of vaccines available against pertussis (whooping cough), an infectious disease of the respiratory tract that can be extremely serious in very young children. Both have advantages and disadvantages: The acellular form (aP, mainly used in resource-rich countries) does not appear to offer as long lasting protection, but the whole cell vaccine (wP, mainly used in LMIC) appears to be generally more reactogenic. There is consensus that a "better pertussis vaccine" ought to be designed. The GaPs trial is part of a series of clinical trials performed by the PERtussIS COrrelates of Protection Europe (PERISCOPE) Consortium, an EU-funded group of investigators which aims to generate knowledge on immune responses to pertussis. A better understanding of human biomarkers of protective immune responses to B. pertussis and its waning immunity is needed to accelerate the design and testing of new pertussis vaccines with a longer duration of protection. This proposal describes the design and objectives of the clinical trial to be conducted in the Gambia, which is the only site in Africa involved in the consortium and involves the recruitment of 600 mother/infant pairs. Pregnant women will be randomised to receive either the usually recommended tetanus vaccination or a combination vaccine against whooping cough, diptheria, tetanus and polio. Their infants will receive either aP or wP as part of their EPI vaccines, and resulting immune responses will be characterized in detail up to the age of 9 months. The investigators will use immunological assays to investigate the functional humoral and cellular responses to pertussis in infants born to mothers who are randomized to receiving pertussis vaccine in pregnancy or not, and their infants who will receive either aP or wP vaccine. Our research questions are: Does vaccination against pertussis in pregnancy have impact on subsequent immune responses to pertussis vaccine and other EPI vaccines in the infants Does vaccination of infants with wP vaccine induce different levels and functionality of antibody and/or T cell responses than vaccination with aP vaccine What is the difference in innate and acquired immunity- as measured with novel systems vaccinology tools- between being vaccinated with wP versus aP?
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.
Streptococcus pneumoniae is responsible for over 10 percent of death in children under five and many of these deaths occur in early infancy before the current pneumococcal schedule is effective and nearly half occur in sub Saharan Africa. The PROPEL trial will examine the effect of either a maternal or a neonatal dose of a pneumococcal conjugate vaccine on pneumococcal colonisation in the nose which can be used to measure the risk of disease in early life. 600 Expectant mothers will be randomized at between 28 and 34 weeks to a maternal group, a neonatal group or a control group in equal number (200 per group). Their subsequent born offspring will be followed up until nine months of age. Infants born from expectant mothers in the maternal and control group will receive their subsequent pneumococcal conjugate vaccination according to the national Expanded Programme on Immunisation (EPI) schedule in the Gambia at 8, 12 and 16 weeks while infants born to expectant mothers in the control group will receive the pneumococcal conjugate vaccine within 48 hours of birth and at 8 and 16 weeks of life. Randomization will be undertaken by defined un-blinded members of the clinical trial team who will be delegated for this task and who will not be involved in any other trial related procedures Pregnant women who are willing and who are identified by the staff of the government antenatal clinic as being potentially eligible according to gestation (assessed initially according to the date of the last menstrual period (LMP) - if known, or the fundal height), will be referred to a member of the clinical trial team. Those who remain interested in participation having had the details of the study explained will have basic demographic, obstetric and contact details collected and will be invited, at a time of their convenience, to the Medical Research Council (MRC) clinical trial site for the formal informed consent process to be completed. Following informed consent, pregnancy will be confirmed with a urinary pregnancy test. Initial screening (e.g. for past-obstetric history and past-medical history etc) will be undertaken at this point along with screening bloods for serology (HIV, hepatitis B and syphilis) and haematology (haemoglobin and sickle test). A dating ultrasound scan (USS) will also be undertaken by designated clinical trial staff. On completion of screening, expectant mothers who are confirmed to be eligible according to the defined inclusion and exclusion criteria will be enrolled and randomized in parallel into one of three equally sized groups mentioned above (maternal, neonatal, control). According to the group into which they have been randomized, mothers will receive a dose of PCV13 and tetanus toxoid [maternal group], placebo (0.9% sodium chloride) and tetanus toxoid [control group] or tetanus toxoid alone [neonatal group]. From this point on, the maternal and control groups (now 'Routine EPI Schedule') will be followed up in exactly the same way for the purposes of interventions and all endpoint assessments. Infants in the neonatal group ('Neonatal Schedule') will be followed up according to the schedule outlined. At the time of presentation to the delivery unit a blood sample for serology and malaria Rapid Diagnostic Test (RDT) and an nasopharyngeal swab (NPS) sample will be obtained prior to or shortly following delivery. Immediately following delivery a sample of cord blood will be obtained and as soon as possible an NPS sample will be taken from the newborn. Anthropometric measurements will be taken from the newborn and an examination conducted. Once there has not been any contraindication to vaccination identified, all newborns will be administered the routine EPI vaccines according to the schedule in The Gambia (BCG, Hepatitis B and OPV). Those newborns in the Neonatal group will additionally be administered a single intramuscular (IM) dose of PCV13. At two, three and four months, infants will be administered the routine EPI vaccines. Those infants in the Maternal and Control Groups (Routine EPI Schedule) will additionally receive PCV13 at eight, 12, and 16 weeks while those in the Neonatal group will receive the vaccine at eight and 16 weeks only having received the first dose at birth. All infants will additionally receive a single dose of the inactivated poliovirus vaccine (IPV) at 16 weeks in line with the routine EPI schedule in The Gambia. Following the vaccines administered to expectant mothers and following the vaccines administered at birth, home visits will be undertaken on day 1 to 6 to collect solicited local and systemic adverse (for PCV only) reactions and any unsolicited. A day 7 safety clinic visit will be conducted following the vaccines administered to expectant mothers and following the vaccines administered at birth. Infant will attend the clinical trial site for NPS and blood samples to be taken at specific time points.
Vitamin A supplementation (VAS) significantly reduces all-cause mortality when given after 6 months of age, but has a null or detrimental effect when given between 1-5 months. Studies of neonatal VAS (NNVAS) have produced conflicting findings. These age-pattern variations might result from immunological interactions between VAS and vaccines. The potential efficacy of NNVAS is being retested in 3 large new intervention trials with mortality as endpoint. Complementary mechanistic studies in animals and in human infants in The Gambia (this proposal) and Bangladesh have been commissioned to run in parallel. The investigators will use a 2-arm double blind RCT to test whether NNVAS modulates the early ontogeny of human immune development. Neonates, recruited through a peri-urban clinic in The Gambia, will receive either 50,000 International Units (IU) VAS orally within 48 hours of birth (intervention group, n=100) or a placebo (control group, n=100). Male and female neonates will be randomized separately at enrolment for later analyses by sex. All infants will be followed up from birth to age 1 year. A broad panel of immunological outcomes will examine whether NNVAS: a). normalises thymic development (thymic index by ultrasound); b). skews mycobacterial and recall antigen responses towards a Th2 profile; c). diminishes Th1 and Th17 reactivity to mycobacterial and recall antigens; d). diminishes the tuberculin skin test (TST) response; e). causes increased innate immune reactivity; f). increases the frequency of circulating regulatory T cells (Tregs) expressing gut homing receptors; g). enhances B cell immune responses after routine vaccination (increase of B cell numbers and activation status); h). increases circulating IgA in mucosal immune compartment, especially oral polio vaccine (OPV) specific IgA post-vaccination; i). decreases bacterial translocation, by improving mucosal barrier function; and j). decreases markers of infection or inflammation. Growth and morbidity will also be assessed.