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Trial no.:
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PACTR202309751708712 |
Date of Registration:
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13/09/2023 |
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Trial Status:
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Registered in accordance with WHO and ICMJE standards |
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| TRIAL DESCRIPTION |
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Public title
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Experimental Human Pneumococcal Challenge with Streptococcus pneumoniae serotype 3 |
| Official scientific title |
Serotype 3 Dose ranging and reproducibility Experimental Human Pneumococcal Challenge in healthy volunteers |
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Brief summary describing the background
and objectives of the trial
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Streptococcus pneumoniae (SPN) is a major cause of morbidity and mortality from a lower respiratory tract infection globally, as well as causing pneumonia, meningitis, and sepsis. Nasopharyngeal carriage of pneumococcus is a prerequisite for pneumococcal disease and transmission of the bacterium and thus represents a risk to carriers themselves and to the wider community. Since the global introduction of pneumococcal conjugated vaccines (PCVs), the rates of pneumococcal disease have declined for many of the vaccine type (VT) serotypes but serotype 3 (SPN3) continues to cause significant disease. This may be due to the higher ‘force of infection’ where intense transmission overcomes vaccine-induced immunity or it may be a unique property of the type 3 capsule which is abundant and shed in large quantities by the bacteria.
The Experimental Human Pneumococcal Challenge (EHPC) model, developed by our team, is a unique method of determining pneumococcal colonisation rates, understanding the impact of colonisation on acquired immunity and for testing pneumococcal vaccines. This safe and reproducible EHPC model has been established in Liverpool and transferred to Malawi using SPN6B and has demonstrated acceptability to local stakeholders and feasibility in healthy adults. To increase the relevance of the EHPC model and its use for vaccine development, we will develop a serotype 3 EHPC model to address some pertinent questions on the burden of pneumococcal disease in Malawi and similar sub-Saharan African settings.
The study will consist of a dose ranging and safety study and a reproducibility study. Sequential cohorts of 10 healthy participants will be challenged with escalating doses of SPN3 in the dose ranging study, aiming to reach 60% carriage. Nasal wash samples will be collected for determination of carriage. The reproducibility part of the study will ideally use a dose that results in ≥60% of carriage, and with a high safety profile. A total of 33 participants will be enrolled in this cohort to check for reproducibility of the carriage rate. Various samples will be collected for determination of both local and systemic immunological responses to pneumococcal challenge. |
| Type of trial |
Observational |
| Acronym (If the trial has an acronym then please provide) |
SPN3 |
| Disease(s) or condition(s) being studied |
Ear, Nose and Throat,Respiratory |
| Sub-Disease(s) or condition(s) being studied |
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| Purpose of the trial |
Controlled human infection model or human infection study |
| Anticipated trial start date |
18/09/2023 |
| Actual trial start date |
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| Anticipated date of last follow up |
31/05/2024 |
| Actual Last follow-up date |
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| Anticipated target sample size (number of participants) |
83 |
| Actual target sample size (number of participants) |
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| Recruitment status |
Not yet recruiting |
| Publication URL |
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