A Phase 2 interventional study of GC4006A and GC4006A in Covid-19 Prevention, sponsored by GC Biopharma Corp. Enrolling by invitation at 1 site in South Korea. Open to participants aged 19 Years to 85 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-13.
Sponsored by GC Biopharma Corp · Phase 2, Interventional, and Prevention
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Among 90 studies in COVID-19 with a site in Korea, Republic of — 11 open to participants now, 19 under way, 6 of them phase 3. COVID-19 · Korea, Republic of.
Among the 90 studies in COVID-19 with a site in Korea, Republic of, this one is the 39th largest by planned enrollment of the 72 interventional ones that give a count, is one of 4 that started in 2026, is one of 17 in phase 2, reaches primary completion later than 11 of the 18 other live ones, and was the 90th registered.
7,993 studies on the registry are indexed under COVID-19; 466 are open to participants now.
Browse COVID-19 studies →11 of the 90 studies in COVID-19 with a site in Korea, Republic of are open now. Recruiting first, the newest first:
Pfizer · Sites in Korea, Republic of, United States, Argentina and 15 more countries
Ages 18+
Pfizer · Sites in Korea, Republic of, United States, Argentina and 16 more countries
Ages 12+
Merck Sharp & Dohme LLC · Sites in Korea, Republic of, United States, Argentina and 21 more countries
Ages 18+
Jaehoon Ko · Sites in Korea, Republic of
Ages 19+
Pfizer · Sites in Korea, Republic of
Ages 19+
A study can be open while its sites in Korea, Republic of have not opened yet or have stopped. Only those recruiting at a site in Korea, Republic of →
Of the 356 COVID-19 studies recruiting now, 206 (58%) set no upper age limit and 83 (23%) stop at 75 or younger; 91 take children under 18; 135 take healthy volunteers.
This study: 19 Years to 85 Years · all sexes · healthy volunteers too.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
90 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 20 · Phase 2 31 · Phase 3 30 · Phase 4 2
First in 2018; this study’s year is marked. 4 started in 2026.
By drug class, each counting the studies that test any of its medicines:
This study's planned enrollment of 210 is above the median of 102 across 4,365 interventional studies indexed under COVID-19.
Median enrollment 253 across the 72 interventional studies, 730 across the 18 observational. Of the 58 that completed or were terminated, 21 (36%) have results posted.
This tab as a report to print or save as PDF → With an account.
64 of 90 have an industry lead sponsor. The 10 most frequent:
This study is registered under GC Biopharma Corp, one of the names counted as GC Biopharma Corp.. Under that name alone:
GC Biopharma Corp is the lead sponsor of 16 studies on the registry; 6 are open to participants now.
GC Biopharma Corp. has 3 studies filed under COVID-19 — fewer than ten, so there is no comparison to draw.
7 of the studies in COVID-19 with a site in Korea, Republic of that are under way reach primary completion within a year, 3 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT07013474Phase 3PfizerA Study to Learn About the Study Medicine Ibuzatrelvir in Adults With COVID-19 Who Are Severely Immunocompromised | 2027-09-28 |
| NCT06679140Phase 3PfizerA Study to Learn About a Study Medicine Called Ibuzatrelvir in Adult and Adolescent Patients With COVID-19 Who Are Not Hospitalized But Are at Risk For Severe Disease | 2027-10-01 |
| NCT05624450Phase 3AstraZenecaEfficacy and Safety of Tozorakimab in Patients Hospitalised for Viral Lung Infection Requiring Supplemental Oxygen | 2027-11-04 |
| NCT06613984PfizerKorean Post Marketing Surveillance for Comirnaty Injection (Bretovameran) | 2026-12-30 |
| NCT05032976PfizerKorea Comirnaty Post-marketing Surveillance | 2027-01-24 |
Add all 7 to your calendar (.ics) → With an account.
Among the 90 studies in COVID-19 with a site in Korea, Republic of, from their registry updates:
This tab as a report to print or save as PDF → With an account.
The purpose of this study is to evaluate the safety and immunogenicity of the COVID-19 preventive vaccine 'GC4006A' in healthy adults aged 19 to 85 years
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biological: GC4006A
Biological: GC4006A
Biological: COMIRNATY
Intramuscular injection
Intramuscular injection
Intramuscular injection
Differences between groups of Neutralizing Antibody Responses
Assessed by Geometric Mean Titer (GMT, unit: BAU/ml), Geometric Mean Fold Rise (GMFR) from baseline, and Seroresponse Rate (SRR, unit: %). GMFR is expressed as a fold-change without units.
Time frame: up to 4 weeks
Differences between groups of Binding Antibody Responses
Assessed by Geometric Mean Concentration (GMC, unit: BAU/ml), Geometric Mean Fold Rise (GMFR) from baseline, and Seroresponse Rate (SRR, unit: %). GMFR is expressed as a fold-change without units.
Time frame: up to 4 weeks
Differences between groups of Neutralizing Antibody Responses
Assessed by Geometric Mean Titer (GMT, unit: BAU/ml), Geometric Mean Fold Rise (GMFR) from baseline, and Seroresponse Rate (SRR, unit: %). GMFR is expressed as a fold-change without units.
Time frame: up to 52 weeks
Differences between groups of Binding Antibody Responses
Assessed by Geometric Mean Concentration (GMC, unit: BAU/ml), Geometric Mean Fold Rise (GMFR) from baseline, and Seroresponse Rate (SRR, unit: %). GMFR is expressed as a fold-change without units.
Time frame: up to 52 weeks
Change from baseline of T-Cell Mediated Immune Responses
Evaluated by IFN-gamma-secreting T-cell responses and present Th1/Th2 ratio in %.
Time frame: up to 52 weeks
Incidence of Solicited Local and Systemic Adverse Events
Time frame: up to 1 weeks
Incidence of Unsolicited Adverse Events
Time frame: up to 4 weeks
Incidence of Immediate Adverse Events
Time frame: up to 30 minutes
Incidence of Medically Attended Adverse Events (MAAEs) and Adverse Events of Special Interest (AESIs)
Time frame: up to 52 weeks
Plan to share: No
No publications or documents are linked to this record.
Started Oct 2026 (actual). Primary completion is estimated for Oct 2027, 12 months after the start.
Of 223 industry-sponsored phase 2 interventional studies under COVID-19, half reached primary completion within 8 months of starting (the median), counting those still running; a quarter within 5 and three quarters within 13. This study's planned 12 months is above that.
Counting every sponsor, half of 582 studies reached it within 9 months; a quarter within 5 and three quarters within 16.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
No contact was published for this record. The registry link below has the sponsor’s details.
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