NCT05784701

Trivalent Salmonella Conjugate Vaccine (TSCV)

Age-descending, Randomized, Placebo-controlled Phase 2 Trial in Three Sites in Sub-Saharan Africa to Assess the Safety and Immunogenicity of a Parenteral Trivalent Salmonella (S. Enteritidis/S. Typhimurium/S. Typhi Vi) Conjugate Vaccine (TSCV) Versus Placebo

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 800 (estimated)
• Sponsor: University of Maryland, Baltimore · Academic / Other
• Sex: All
• Age: 12 Weeks – 35 Years
• Healthy volunteers: Accepted

Summary

This is an age-descending, randomized, placebo-controlled trial that will evaluate the safety and immunogenicity of a Trivalent Salmonella conjugate vaccine (TSCV). The trial will proceed from adults, to children, to toddlers, and then to infants.

Detailed description

This is an age-descending, randomized, placebo-controlled trial that will evaluate the safety and immunogenicity of a Trivalent Salmonella conjugate vaccine (TSCV). The trial will proceed from adults, to children, to toddlers, and then to infants. In Step 1A-D of the trial, participants will be randomized to receive a single dose of TSCV (Full-strength or Half-strength), Typbar-TCV, or placebo, first in adults, then in children 5 to 9 years of age, then children 24 to 59 months of age, and then 16 to 23 months of age. Participants will be followed for 6 months. After a Data Safety Monitoring Board (DSMB) review of the safety data, the trial will proceed to Step 2A and 2B whereupon 12- to 16-month-old toddlers and infants 8- to 11-months of age will be similarly and simultaneously randomized. Participants will be followed for 6 months. After another DSMB safety review, Step 3 will commence with simultaneous enrollment of 12- to 14-week-old and 16- to 18-week-old infants who will each receive a single dose of TSCV, TCV or placebo. Participants will be followed for 6 months. After a third DSMB safety review and selection of the preferred TSCV formulation (Full-strength versus Half-strength) for further clinical development (a decision taken by the Sponsor, Manufacturer, and funder, while taking into consideration the recommendation of the DSMB), Step 4 will evaluate a two-dose regimen. Infants 12 to 18 weeks of age will be randomized to receive either two doses of TSCV (at Full-strength or Half-strength, based on results from Steps 1-3) or placebo followed by Typbar-TCV. The priming dose will be administered at enrollment and the booster at \~9, \~12, or \~15-17 months of age. Participants will be followed until 6 months after the last study vaccination. Note -- Whenever investigational products are intended to be administered at a scheduled Expanded Program on Immunization visit, they will always be given 2 weeks after the routine EPI vaccines. This will not only avoid interference with EPI vaccines but will provide a convenient contact point for potential recruitment of participants for the study.

Conditions

• Trivalent Salmonella Conjugate Vaccine (TSCV)

Interventions

Type	Name	Description
DRUG	TSCV (Full-strength)	TSCV (Full-strength)
DRUG	TSCV (Half-strength)	TSCV (Half-strength)
DRUG	Typbar-TCV	Typbar-TCV
DRUG	Placebo	Placebo

Timeline

• Start date: 2023-04-05
• Primary completion: 2027-01-05
• Completion: 2027-12-30
• First posted: 2023-03-27
• Last updated: 2025-05-02

Locations

1 site across 1 country: Mali

Regulatory

• FDA-regulated drug study