View clinical trials related to Shigellosis.
Filter by:The goal of this clinical trial is to test a new Shigella vaccine (InvaplexAR-DETOX) in combination with a new adjuvant (dmLT) in healthy participants. The main questions it aims to answer are: - Is the new Shigella vaccine (with and without the new adjuvant) safe and well tolerated? - How wel does the new Shigella vaccine stimulate the immune system in combination with the new adjuvant, and without the new adjuvant? Participants will receive three vaccinations at 28-day intervals. Researchers will compare the results of participants vaccinated with the vaccine in combination with the adjuvant to the results of participants vaccinated with the vaccine only and to the results of participants vaccinated with a placebo (fake vaccine).
Diarrhoea caused by Shigella (shigellosis) is of major public health importance. However, there are no licensed Shigella vaccines in routine use, with several candidates still in various stages of clinical development. Shigella human infection studies (HIS) have played a key role in vaccine development. These models also allow for the evaluation of immunity and other non-immunological parameters that are important to understand resistance and/or susceptibility to disease. This is particularly useful in individuals from endemic areas with varying levels of prior exposure and immunity to Shigella. Thus, establishing a Shigella HIS would enable the testing of interventions such as vaccines in a population that would most benefit from a subsequent vaccine and has potential to accelerate vaccine development. Here, the goal is to successfully establish a Shigella sonnei human infection model in Kenyan adults. This will be achieved by conducting dose-finding and dose verification Shigella studies that safely and reproducibly induce ≥60% attack rates. In this study, investigators aim to use Shigella HIS in healthy adults to develop a model as a platform to test vaccines, to study immune responses identifying potential correlates of infection, and non-immunological factors mediating and influencing susceptibility to disease. To achieve this, the study will be carried out in two phases over a period of 12-14 months. Phase A will enroll (N=up to 40 volunteers) and Phase B will enroll an additional (N=30 volunteers). To be eligible to receive a dose of 53G, volunteers must pass the screening visit. Investigators will vary the dose of bacteria in individuals enrolled for challenge to identify the dose needed to cause ≥60% shigellosis (attack rate) (Phase A) followed by testing and demonstrate the reproducibility of the model (Phase B). Thus, the main outcomes of the study will be: (1) optimisation of bacterial dose for infection success (≥60% attack rate); and (2) safety.
The study is a first-in-human Phase 1/2a randomized, double-blind, placebo-controlled trial to assess the clinical safety and efficacy of ShigActive in healthy adults with experimental Shigella challenge.
The purpose of this study is to evaluate the efficacy, immunogenicity and safety of S. Flexneriza-S. Sonnei Bivalent Conjugate Vaccine in infants and children aged from 6 months to 5 years.
Background (brief): Shigellosis is the second leading cause of death due to diarrheal diseases worldwide (>200,000 deaths/year). Though the mortality rate associated with Shigellosis has decreased, the fact that the bacteria have acquired resistance to multiple antibiotics, is a cause for major concern. Oral azithromycin and intravenous ceftriaxone are the recommend first and second line therapies, respectively in Bangladesh. Approximately 20% of Shigella isolates are resistant to azithromycin suggesting that a substantial number of children will require second-line therapy. While resistance to ceftriaxone in shigellosis is low in Bangladesh at 5%, the potential for rapid emergence of antibiotic resistance to this third-generation cephalosporin and ceftriaxone's resource-intensive delivery method, underscore the need for evidence-based alternative antibiotic regimens for multidrug resistant Shigella infections Hypothesis: Children treated with tebipenem-pivoxil will have no worse clinical and microbiologic failure rates compared to ceftriaxone. Primary Aim To determine whether tebipenem-pivoxil is clinically non-inferior to the currently WHO-recommended second line Shigella therapy (ceftriaxone) 3 days after treatment initiation. Hypothesis: Children randomized to tebipenem-pivoxil experience no more clinical failures than children treated with ceftriaxone 3 days after treatment initiation. Secondary Aim: To determine whether tebipenem-pivoxil is clinically non-inferior to the currently WHO-recommended second line Shigella therapy (ceftriaxone) 7 and 30 days after treatment initiation. To determine whether tebipenem-pivoxil is microbiologically non-inferior to the currently WHO-recommended second line Shigella therapy (ceftriaxone) 7 and 30 days after treatment initiation. Describe the number of adverse events, between children with shigellosis treated with oral tebipenem-pivoxil or IV ceftriaxone. Compare the prevalence of ceftriaxone and carbapenam resistance, as well as ESBL-and carbapenemase-producing Escherichia coli, in children treated with tebipenem-pivoxil or ceftriaxone 7 and 30-days after initiation of second-line therapy. Methods: Investigators propose a phase IIb randomized controlled trial (RCT) to determine the efficacy and safety of oral tebipenem-pivoxil, compared to IV ceftriaxone, for children with Shigella infections unresponsive to first-line antibiotic therapy. Bangladeshi children aged 24 to 59 months with suspected Shigella infections and no clinical improvement within 48 hours of first-line therapy will be randomized to a 3-day course of oral tebipenem-pivoxil (4 mg/kg 3x daily) or 3-days of IV ceftriaxone (50 mg/kg 1x daily). The children will be evaluated for key clinical, microbiologic, and safety outcomes during the subsequent 30-day period. Additionally, investigators propose a lead in study of 15 patients to confirm the safety profile and pharmacokinetics and efficacy of tebipenem in the study population. During this pharmacokinetic study period investigators will compare 15 children with oral Tebipenem randomizing with 15 children with oral Azithromycin arm. Investigators will also check invitro susceptibility of Tebipenem-pivoxil in 200 shigella isolates prior to the clinical trial in collaboration with Infectious Diseases Division, icddr,b. Randomization Block randomization (1:1) in random sized blocks of will be used to assign treatment groups at study enrollment by an independent statistician. Treatment allocation (once assigned) will be known to the managing clinician and the participant due to the differing drug delivery mechanisms of the two antibiotics (oral vs. injectable). However, the team conducting the statistical analyses will be blinded to treatment allocation (allocation will appear A and B).
The study will compare the shigellosis rate in subjects previously challenged with a heterologous Shigella serotype to the attack rate in naïve subjects.
In this study, the tetravalent bioconjugate candidate vaccine Shigella4V will be tested to obtain first-in-human data on its safety and immunogenicity in infants and to identify the preferred dose of Shigella4V in 9 month old infants.
The purpose of this study is to assess the efficacy of 3 days of azithromycin (AZI) compared to 3 days of ciprofloxacin (CIP) (standard-of-care) for the treatment of children hospitalised with dysentery in Ho Chi Minh City.
This is a first-in-human, single-center, single-blinded, observer-masked randomized, dose escalation (two doses), placebo-controlled study in healthy volunteers.
In this proof of concept challenge study, the bioconjugate candidate vaccine Flexyn2a will be tested for its ability to induce an immune response that protects healthy adult volunteers from infection with a wild-type Shigella flexneri 2a strain compared to subjects receiving placebo.