Please select the arm or intervention descriptions that belong to the clinical trial below.
Title: Effect of Extended Dose Intervals on the Immune Response to Oral Cholera Vaccine
Brief 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.


Options:
A: Arm Label: 1; Type: EXPERIMENTAL; Interventions: Biological: killed whole cell oral cholera vaccine | Arm Label: 2; Type: PLACEBO_COMPARATOR; Interventions: Biological: Heat Killed E. coli | Intervention Type: BIOLOGICAL; Name: killed whole cell oral cholera vaccine; Assigned to Arm(s): 1 | Intervention Type: BIOLOGICAL; Name: Heat Killed E. coli; Assigned to Arm(s): 2
B: Arm Label: 1; Type: EXPERIMENTAL; Interventions: Biological: rBS-WC vaccine | Intervention Type: BIOLOGICAL; Name: rBS-WC vaccine; Assigned to Arm(s): 1
C: Arm Label: Shanchol; Type: EXPERIMENTAL; Interventions: Biological: Shanchol | Arm Label: Placebo; Type: PLACEBO_COMPARATOR; Interventions: Biological: Placebo | Intervention Type: BIOLOGICAL; Name: Shanchol; Assigned to Arm(s): Shanchol | Intervention Type: BIOLOGICAL; Name: Placebo; Assigned to Arm(s): Placebo
D: Arm Label: Shanchol Dose-interval Group 1; Type: ACTIVE_COMPARATOR; Interventions: Biological: Oral Cholera Vaccine | Arm Label: Shanchol Dose-Interval Group 2; Type: EXPERIMENTAL; Interventions: Biological: Adjusted Dose Oral Cholera Vaccine | Intervention Type: BIOLOGICAL; Name: Oral Cholera Vaccine; Assigned to Arm(s): Shanchol Dose-interval Group 1 | Intervention Type: BIOLOGICAL; Name: Adjusted Dose Oral Cholera Vaccine; Assigned to Arm(s): Shanchol Dose-Interval Group 2

Answer: D