Safety and Efficacy Challenge Study of CVD 1208S, a Live, Attenuated Oral Vaccine to Prevent Shigella: Phase IIb
Tracking Information | |||||
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First Received Date ICMJE | March 19, 2009 | ||||
Last Updated Date | March 29, 2010 | ||||
Start Date ICMJE | January 2010 | ||||
Estimated Primary Completion Date | May 2011 (final data collection date for primary outcome measure) | ||||
Current Primary Outcome Measures ICMJE |
To measure the protective efficacy of 3 spaced doses of vaccine against experimental challenge with wild type S. flexneri 2a 2457T [ Time Frame: approximately October 2010 ] [ Designated as safety issue: No ] | ||||
Original Primary Outcome Measures ICMJE | Same as current | ||||
Change History | Complete list of historical versions of study NCT00866242 on ClinicalTrials.gov Archive Site | ||||
Current Secondary Outcome Measures ICMJE |
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Original Secondary Outcome Measures ICMJE | Same as current | ||||
Current Other Outcome Measures ICMJE | |||||
Original Other Outcome Measures ICMJE | |||||
Descriptive Information | |||||
Brief Title ICMJE | Safety and Efficacy Challenge Study of CVD 1208S, a Live, Attenuated Oral Vaccine to Prevent Shigella: Phase IIb | ||||
Official Title ICMJE | Safety, Immunogenicity, and Efficacy Following Experimental Challenge of CVD 1208S, a Delta guaBA, Delta Sen, Delta Set Shigella Flexneri 2a Live, Oral Vaccine: Phase IIb Challenge Study | ||||
Brief Summary | 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. |
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Detailed Description | The study comprises a Phase 2 vaccination study and a Phase 2b challenge study. The primary objectives of the Phase 2 vaccination study are: 1. To evaluate, in healthy volunteers, the safety and clinical acceptability of three spaced doses (one month apart) of an investigational, live, oral, attenuated vaccine called CVD 1208S, with particular attention to the occurence of diarrhea, dysentery, and fever, and 2. To characterize immune responses following ingestion of this vaccine. The primary objective of the Phase 2b challenge study is to measure the protective efficacy of 3 spaced doses of vaccine after ingestion of an oral challenge strain called Shigella flexneri 2a strain 2457T. Shigella is a leading cause of disease and death among children younger than 5 years living in developing countries. The difficulty controlling this infection has led experts to believe that prevention with the use of a vaccine is a promising strategy. At the CVD, we have pursued an approach of developing an oral, attenuated Shigella vaccine that prevents infection with the Shigella types of greatest clinical and epidemiologic importance. One of the strains to be included in the vaccine is called Shigella flexneri 2a. Investigators at the CVD have created a vaccine from Shigella flexneri 2a, designated CVD 1208S, using molecular biology techniques. To date, nearly 40 subjects have received varying doses of this vaccine with good clinical tolerance and modest immunogenicity. Previously a single dose of vaccine was used. In the current study, we will administer doses of vaccine on days 0, 28, and 56 to attempt to maximize immunogenicity. Approximately one month after the 3rd dose, a group of ~15-20 vaccinated volunteers along with a similar number of unvaccinated control subjects will be admitted to the CVD Research Isolation Ward at SNBL and challenged with wild type Shigella flexneri 2a. By comparing the attack rate of illness in vaccinated vs. unvaccinated subjects, we will determine the vaccine's ability to confer protective immunity. |
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Study Type ICMJE | Interventional | ||||
Study Phase | Phase 2 | ||||
Study Design ICMJE | Endpoint Classification: Safety/Efficacy Study Intervention Model: Single Group Assignment Masking: Open Label Primary Purpose: Prevention |
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Condition ICMJE | Shigella | ||||
Intervention ICMJE | Biological: CVD 1208S, Challenge strain of wild-type Shigella flexneri 2a
The challenge strain consists of freshly harvested Shigella flexneri 2a strain 2457T diluted in phosphate buffered saline to reach the desired inoculum Form: liquid Dose 10 to the 3rd power CFU in 1.0 ml Route: oral. |
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Study Arm (s) | Experimental: Challenge-recipients
Intervention: Biological: CVD 1208S, Challenge strain of wild-type Shigella flexneri 2a |
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Publications * | |||||
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline. |
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Recruitment Information | |||||
Recruitment Status ICMJE | Suspended | ||||
Estimated Enrollment ICMJE | 55 | ||||
Estimated Completion Date | May 2011 | ||||
Estimated Primary Completion Date | May 2011 (final data collection date for primary outcome measure) | ||||
Eligibility Criteria ICMJE | Inclusion Criteria:
Exclusion Criteria:
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Gender | Both | ||||
Ages | 18 Years to 45 Years | ||||
Accepts Healthy Volunteers | Yes | ||||
Contacts ICMJE | Contact information is only displayed when the study is recruiting subjects | ||||
Location Countries ICMJE | United States | ||||
Administrative Information | |||||
NCT Number ICMJE | NCT00866242 | ||||
Other Study ID Numbers ICMJE | HP-00040710 Phase IIb, Shigella CVD 27000 | ||||
Has Data Monitoring Committee | No | ||||
Responsible Party | Karen L. Kotloff, M.D., Principal Investigator, University of Maryland, Baltimore Center for Vaccine Development | ||||
Study Sponsor ICMJE | University of Maryland | ||||
Collaborators ICMJE | Program for Appropriate Technology in Health | ||||
Investigators ICMJE |
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Information Provided By | University of Maryland | ||||
Verification Date | March 2010 | ||||
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP |