Effect of Extended Dose Intervals on the Immune Response to Oral Cholera Vaccine

Summary

Cholera is a life-threatening disease if prompt actions are not taken. The most recent estimates of the global burden of cholera estimate that there are more than 1.3 billion people at risk. Of which, 2.86 million (range: 1.3-4.0 million) will contract cholera and 95,000 (21,000-143,000) will die each year. A safe, effective, and affordable killed whole-cell oral cholera vaccine (OCV) is now being used widely to prevent cholera in areas at risk. This regimen demonstrated 65% efficacy retained for at least 3 years and even up to 5 years in an endemic setting.

The primary aim of this project is to determine changes in the vibriocidal geometric mean titers (GMT) in subjects who receive the second dose of oral cholera vaccine (OCV) at different intervals: 2 weeks, or 6 months following the first dose of vaccine. Secondary aims include a) vibriocidal antibody response rates in subjects who receive OCV at 2 weeks or 6 months following the first dose of vaccine, b) age specific serum vibriocidal GMTs following the second dose among participants given the second dose of OCV at intervals of 2 weeks or 6 months following the first dose of vaccine, c) GMT and antibody response rates of Immunoglobulin A (IgA) and Immunoglobulin G (IgG) anti-lipopolysaccharide (anti-LPS) as measured by ELISA following the second dose among participants given the second dose of OCV at intervals of 2 weeks or 6 months following the first dose of vaccine. Our hypothesis is that the vibriocidal GMT following the second dose, when given after 6 months will not be inferior to the response when the second dose is given according to the standard interval of two weeks.

Conditions

• Cholera
• Vibrio Cholerae Infection

Interventions

BIOLOGICAL

Oral Cholera Vaccine

Shanchol is a bivalent (O1 and O139 serotypes) vaccine using a heat-killed classical Inaba strain and a formalin-killed classical Ogawa strain produced by Sanofi. Shanchol requires no oral buffer for administration, is approved for persons greater than 1 year of age, and requires 2 doses at two-week intervals. It became World Health Organization (WHO) prequalified in 2011.

BIOLOGICAL

Adjusted Dose Oral Cholera Vaccine

The Adjusted Dose Oral Cholera Vaccine is given in two doses, with the second dose given at six months, rather than the manufacturer described 2 week interval between first and second dose.

Sponsors & Collaborators

• Johns Hopkins Bloomberg School of Public Health

  lead OTHER

Principal Investigators

• Amanda K Debes, PhD · Johns Hopkins Bloomberg School of Public Health

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

1 Year

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2017-11-16

Primary Completion

2019-10-16

Completion

2020-12-01

Countries

• Zambia

Study Locations