GC3111B versus Boostrix® as a Tdap booster in healthy adults
An Open(Part 1), Single-arm(Part 1), Randomized(Part 2), Double-blind(Part 2), Active-controlled(Part 2) Phase I/II Clinical Trial to Evaluate the Safety and Efficacy (Immunogenicity) of GC3111B in Healthy Adults
PHASE1; PHASE2 · GC Biopharma Corp · NCT06997627
This study will test whether the GC3111B vaccine is safe and produces protective immune responses comparable to Boostrix® when given as a Tdap booster to healthy adults aged 19–64.
Quick facts
| Phase | PHASE1; PHASE2 |
|---|---|
| Study type | Interventional |
| Enrollment | 120 (estimated) |
| Ages | 19 Years to 64 Years |
| Sex | All |
| Sponsor | GC Biopharma Corp (industry) |
| Locations | 1 site (Seoul) |
| Trial ID | NCT06997627 on ClinicalTrials.gov |
What this trial studies
The trial has two parts: Part 1 is a single-center, open-label, single-group safety evaluation, and Part 2 is a multicenter, double-blind, randomized, active-controlled comparison of GC3111B to Boostrix®. Healthy adults aged 19–64 who have not received a diphtheria-, tetanus-, or pertussis-containing vaccine in the previous 2 years are eligible, while recent vaccination, pregnancy, breastfeeding, or recent participation in other investigational trials are excluded. Participants will receive either GC3111B or Boostrix® and be followed for safety and antibody responses (immunogenicity) over predefined visits. The primary outcomes focus on safety/tolerability and laboratory measures of immune response to the vaccine antigens.
Who should consider this trial
Good fit: Healthy adults aged 19–64 who have not had a diphtheria-, tetanus-, or pertussis-containing vaccine in the past 2 years, are not pregnant or breastfeeding, and have not received other vaccines or investigational products within the specified exclusion windows are the ideal candidates.
Not a fit: People who recently received a Tdap or other vaccine within the exclusion windows, are pregnant or breastfeeding, or recently joined other investigational trials are unlikely to be eligible or to benefit from participation.
Why it matters
Potential benefit: If successful, GC3111B could provide a safe, effective alternative Tdap booster to Boostrix®, increasing vaccine options and supply.
How similar studies have performed: Licensed Tdap vaccines like Boostrix® have well-established safety and immunogenicity profiles, and other biosimilar/alternate Tdap candidates have shown comparable results in prior trials.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Healthy adults aged 19 to 64 years old as of the date of written consent. * Individuals with no history of vaccination with a vaccine containing diphtheria, tetanus, or pertussis antigens within the past 2 years prior to administration of the investigational product. Exclusion Criteria: * Individuals who have received a vaccine within 4 weeks prior to administration of the investigational product. * Individuals with a history of Tdap vaccination prior to administration of the investigational product. * Pregnant and breastfeeding women. * Individuals who have participated in other clinical trials involving investigational products/devices within 6 months prior to administration of the investigational product.
Where this trial is running
Seoul
- The Catholic Univ. of Korea Eunpyeong St. Mary's Hospital — Seoul, South Korea (RECRUITING)
Study contacts
- Study coordinator: Minji Ko
- Email: minji.ko@gccorp.com
- Phone: +82-31-260-9143
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions: Tetanus-diphtheria-acellular Pertussis