20 Clinical Trials for Various Conditions
The purpose of this study is to determine whether SF2a-TT15 (a monovalent synthetic carbohydrate-based conjugate Shigella vaccine) is safe and effective in the prevention of Shigella infection.
This is a research study about an experimental (investigational) oral inactivated whole cell Shigella flexneri 2a killed vaccine (Sf2aWC) and an adjuvant called dmLT. Sf2aWC is a killed vaccine that is being made to prevent disease from Shigella., which causes bloody, watery diarrhea. An adjuvant is something that is added to a vaccine to make it work better. The purpose of the study is to see if the vaccine will protect people from Shigella infection with or without an adjuvant called dmLT. About 72 healthy adults, ages 18-45, will participate in this study. The study will compare 2 different vaccination groups and 1 control group. Volunteers have an equal chance to be in any of the 3 groups. Study procedures include: stool samples, blood samples and documenting side effects. Participants will be involved in study related procedures for about 6 months.
Development of an S. sonnei human challenge model using a newly manufactured lyophilized lot of S. sonnei strain 53G (Lot 1794) that can be used in the future as a challenge strain for all S. sonnei vaccine candidates. An adaptable dosing plan was used to determine the dose of Shigella sonnei 53G that induces the primary outcome in approximately 60% of subjects.
The purpose of this study is to determine whether CVD 1208S (a live, attenuated, oral vaccine) is safe and effective in the prevention of Shigella infection.
This is a research study about an experimental (investigational) oral inactivated whole cell Shigella flexneri 2a killed vaccine (Sf2aWC). Sf2aWC is a killed vaccine that is being made to prevent disease from Shigella., which causes bloody, watery diarrhea. Infants and children living in developing countries experience the greatest consequences of this disease. The purpose of this study is to find a dose of the vaccine that is safe, tolerable, and develops an immune response. About 82 healthy adults, ages 18-45, will participate in this study. This study will require volunteers to stay in the research facility for several nights for the first dose. Participants in Cohorts 2, 3, and 4 will not be required to stay overnight for the second and third doses. Participants will be assigned to receive 1 of 4 vaccine doses by mouth. Study procedures include: stool samples, blood samples and documenting side effects. Participants will be involved in study related procedures for about 8 months.
The purpose of this study is to determine whether CVD 1208S (a live, attenuated, oral vaccine) is safe and effective in the prevention of Shigella infection.
The purpose of this study is to determine whether CVD 1208S (a live, attenuated, oral vaccine) is safe and effective in the prevention of Shigella infection.
In this challenge study, the bioconjugate candidate vaccine Shigella4V2 will be tested for its ability to induce an immune response that protects healthy adult volunteers from infection with a wild-type Shigella sonnei strain compared to participants receiving placebo.
The purpose of this study is to determine whether a live, oral, combined Shigella-ETEC vaccine candidate, known as strain CVD 1208S-122, is safe and immunogenic.
This is a trial to evaluate the safety, reactogenicity, immunogenicity and efficacy of a 10\^6 cfu dose of an oral live-attenuated S. sonnei vaccine candidate, WRSs2, in up to 120 healthy males and non-pregnant females aged 18-49, inclusive. This is a two-phase study, an outpatient WRSs2 vaccination phase and an inpatient S. sonnei 53G challenge phase. After the initiation of the study, two participants had Grade 3 diarrhea and/or vomiting in the days following vaccination. The vaccination dose was reduced to 5X10\^5, enrollment was changed to 2 arms and randomized 2:1 (vaccine: placebo). Participants with morbid obesity were excluded and weight loss medications prohibited. The Primary Objective of this study is to estimate combined vaccine efficacy of 2 doses of WRSs2 (10\^6 cfu or 5X10\^5 cfu) in preventing shigellosis, following challenge with S. sonnei strain 53G.
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 evaluate the efficacy, safety and immunogenicity of the GSK3536852A vaccine, which was designed to protect against shigellosis caused by Shigella sonnei (S. sonnei) and is using the new Generalized Modules for Membrane Antigens (GMMA) platform technology developed by GlaxoSmithKline (GSK) Vaccines Institute for Global Health (GVGH). The study vaccine could be the stepping stone for the development of a multivalent broadly protective Shigella vaccine for vaccination of impoverished communities where shigellosis is endemic. However, a standalone monovalent vaccine against S. sonnei could be used to protect travelers against diarrheal shigellosis, as the vast majority of travelers' shigellosis is caused by S. sonnei, and even to protect infants in endemic regions where shigellosis is primarily caused by S. sonnei. The GSK3536852A vaccine has been tested in two Phase I dose escalation studies in Europe to assess its safety and immunogenicity via three routes of administration: intramuscular (IM), intranasal (IN) and intradermal (ID). The results from the first study (dose escalation with IM vaccination) have shown that the vaccine has an acceptable safety profile and is well-tolerated up to a dose of 100 micrograms (µg). The results from the second study (dose escalation with ID, IN and IM vaccination) showed that GSK3536852A vaccine is well-tolerated also when administered by the ID and IN routes of vaccination. However, immunogenicity data have shown that GSK3536852A vaccine administered by the ID and IN routes is not as immunogenic as GSK3536852A vaccine administered by the IM route. Therefore, it has been decided to proceed with the clinical development program of this vaccine only using the IM vaccination route. In terms of dosage, the regimen tested in Phase I studies (three doses given one month apart) did not show any significant benefit from the third dose in terms of immunogenicity, therefore a two dose schedule was selected for next studies. A Phase IIa study, conducted in endemic regions of Africa (i.e., Kenya), has been completed and confirmed the acceptable safety profile and immunogenicity of GSK3536852A vaccine. Performing this vaccine-human challenge study may give the opportunity to establish evidence of clinical protection induced by the candidate S. sonnei vaccine (GSK3536852A vaccine) at an early development stage.
This study is an open-label, dose-escalating Phase 1 investigation of S. flexneri 2a InvaplexAR vaccine. A total of up to 40 subjects will receive one of four S. flexneri 2a InvaplexAR vaccine doses. The vaccine will be administered intranasally (without adjuvant).
This is a phase I, single-blind, randomized, placebo-controlled, single-center study in healthy subjects using a staggered approach to dosing. 30 subjects will be randomized to receive 10 μg Flexyn2a candidate vaccine with or without adjuvant or placebo.
Phase 1, randomized, double-blind, placebo controlled, dose-escalation, inpatient study of single doses of S. sonnei. Health adult subjects, ranging in age from 18 to 45 years of age (inclusive) will be screened. Enroll serial groups up to 90 subjects. The primary objective is to evaluate safety and tolerance of WRSs2 by monitoring presence, frequency and severity of clinical signs and symptoms. A secondary objective is to evaluate the immune response in blood and stool following ingestion of WRSs2 and WRSs3.
The purpose of this study is to select a safe and immunogenic dose of Invaplex 50 intranasal vaccine, and to assess protection of Invaplex 50 intranasal vaccine against diarrhea, dysentery, and fever following challenge with the Shigella flexneri 2a 2457T strain.
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 main purpose of this study is to evaluate the safety of a Shigella flexneri 2a detoxified artificial invasin complex (Invaplex\[AR-Detox\]) vaccine candidate administered by intramuscular immunization.
This study is to determine the safety and immunogenicity of an Enterotoxigenic Escherichia coli (ETEC) candidate vaccine, attenuated recombinant Double Mutant Heat-Labile Toxin (dmLT) from ETEC, administered by the Intradermal (ID) route. The sample size has been determined based on the historic sample, not on power calculations.The study will involve 99 subjects (83 vaccinees and 16 placebo controls) in 4 consecutive cohorts of 16 individuals each (13 vaccinees and 3 placebo controls) and the final cohort of 35 (31 vaccinees and 4 placebos) subjects. The primary objective is to assess the safety and tolerability of dmLT vaccine when administered in three doses intradermally over a range of dosages in healthy adult subjects.
The vaccine is given as a nose spray. Volunteers will receive a 3-dose vaccination with doses spaced two weeks apart. Volunteers will be assigned to a vaccination group based on their order of enrollment with consideration of their availability to complete the necessary vaccinations and follow-up visits.