GLS-5310 Vaccine for the Prevention of SARS-CoV-2 (COVID-19)

Multicenter, Randomized, Combined Phase I Dose-escalation and Phase IIa Double-blind, Placebo-controlled Study of the Safety, Tolerability, and Immunogenicity of GLS-5310 DNA Vaccine, Administered Intradermally Against SARS-CoV-2 in Healthy Adults

This clinical trial will evaluate the safety, tolerability and immunogenicity of GLS-5310 DNA vaccine against SARS-CoV-2(COVID-19) in healthy volunteers.

Study Overview

• Status: Completed
• Conditions: SARS-CoV-2
• Intervention / Treatment: Biological: Placebo; Biological: GLS-5310

Detailed Description

This Phase I / IIa study will assess the safety, tolerability, and immunogenicity of GLS-5310 DNA vaccine.

The Phase I portion of this study is an open-label, dose escalation study to assess two dose levels of GLS-5310 DNA vaccine (0.6 and 1.2 mg) as part of two vaccination regimens (0-8 weeks and 0-12 weeks).

The Phase IIa portion of this study is designed as a randomized, double-blind, placebo-controlled study with only a single active study drug arm. Subjects will be randomized to receive either placebo or GLS-5310 vaccine in a 1:2 ratio.

• Study Type: Interventional
• Enrollment (Actual): 171
• Phase: Phase 2; Phase 1

Contacts and Locations

Study Locations

• South Korea
  • Seoul, South Korea, 08308
    • Korea University Guro Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 19 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Age 19 to 85 years of age (Phase I will be restricted to an upper age limit of 50 years of age)
2. Able to provide informed consent
3. Able and willing to comply with study procedures
4. For women of childbearing potential, able and willing to use an approved form of pregnancy prevention through to 4 weeks post boost vaccination

Exclusion Criteria:

1. Current or planned pregnancy through to 4 weeks post-boost vaccination for women of childbearing potential
2. Currently breastfeeding
3. Current or past participation in a coronavirus (MERS-CoV, SARS-CoV-2) vaccine study
4. Administration of an investigational agent within 6 months of the 1st dose
5. Administration of a vaccine within 4 weeks prior to the 1st dose
6. Administration of immune globulin within 16 weeks of enrollment
7. Administration of an anti-TNFα inhibitor such as infliximab, adalimumab, etanercept, or anti-CD20 monoclonal antibody rituximab within 24 weeks prior to enrollment
8. Current daily treatment of systemic corticosteroids of 20 mg of prednisone or greater, dexamethasone of 3 mg or greater; or the equivalent dose of other systemic corticosteroids
9. Administration of any Immunosuppressive Drug or Immunomodulator within 3 months of the first dose
10. History of bone marrow transplantation
11. Current or planned chemotherapy treatment for hematologic or solid tumor during study period or treatment during the 5 years prior to enrollment
12. Respiratory disease (ex. Asthma, Chronic obstructive lung disease)
13. Cardiovascular disease (ex. myocardial ischemia, congestive heart failure, cardiomyopathy, clinically significant arrhythmia)
14. Hypertension (Systolic pressure >150mmHg or Diastolic pressure >95mmHg)
15. Confirmed Diabetes
16. Severe allergic reaction or anaphylactic reaction after vaccination in the past
17. Immunosuppresion including immunodeficiency disease or family history
18. Positive of serum test at screening (Hepatitis B, Hepatitis A, HIV, Hepatitis C)
19. Baseline screening lab(s) with Non Clinical Significant abnormality
20. Serious adverse reaction to a drug containing Investigational Product (GLS-5310) or other ingredients of the same categories or to a vaccine or antibiotic, nonsteroidal anti-inflammatory disease control, etc. or an allergic history
21. History of hypersensitivity to vaccination such as Guillain-Barre syndrome
22. History of PCR-confirmed infection with SARS-CoV-2 at screening
23. Subjects who have been contact with COVID-19 infections in the past prior to administration, have been classified as COVID-19 confirmed patients, medical patients or patients with symptoms or have been identified with SARS and MERS infection history in the past
24. 37.5 degrees, cough, difficulty breathing, chills, muscle aches, headache, sore throat, loss of smell, or loss of taste within 72 hours prior to administration
25. Healthcare workers participating in the medical examination of patients infected with COVID-19
26. Not willing to allow storage and future use of samples for SARS-CoV-2 related research
27. Prisoner or subjects who are compulsorily detained for treatment of a psychiatric illness
28. Any illness or condition that, in the opinion of the investigator, may affect the safety of the subject or the evaluation of a study endpoint

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: GLS-5310 0.6mg [Group 1a]; 0.6mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.	Biological: GLS-5310; GLS-5310 DNA plasmid vaccine
Experimental: GLS-5310 1.2mg [Group 1b]; 1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.	Biological: GLS-5310; GLS-5310 DNA plasmid vaccine
Experimental: GLS-5310 1.2mg [Group 1c]; 1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 12.	Biological: GLS-5310; GLS-5310 DNA plasmid vaccine
Placebo Comparator: Placebo [Group 2a]; Placebo will be intradermally administered on Day 0 and Week 8 (or Week 12).	Biological: Placebo; Placebo
Experimental: GLS-5310 1.2mg [Group 2b]; 1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8 (or Week 12).	Biological: GLS-5310; GLS-5310 DNA plasmid vaccine

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Number of Serious Adverse Events	Through 48 weeks post vaccination

Secondary Outcome Measures

Outcome Measure	Time Frame
Number of Participants With Positive T Cell Responses Induced by GLS-5310	Post vaccination Visit 4 (4 weeks after week 8 or week 12 vaccination)
Number of Participants With Positive Neutralizing Antibody Responses Induced by GLS-5310	Post vaccination Visit 4 (4 weeks after week 8 or week 12 vaccination)

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Determine IgG antibody responses after a single dose of vaccine related to treatment arm	Endpoint titer of binding antibody in serum at each timepoint	Through 1 year post vaccination
Measure survival rate of animals administered immune serum from vaccinated individuals and later challenged with SARS-CoV-2.	Survival rate	Through 1 year post vaccination
Persistence of immune responses following vaccination with GLS-5310	Endpoint titer of binding antibody in serum at each timepoint; Plaque-reduction neutralizing titer in serum at each timepoint; T-cell response of antigen-specific interferon - gamma (IFN-γ) secretion in PBMC at each timepoint	Through 1 year post vaccination
Determine the extent of immune boosting for participants who are seropositive at baseline following vaccination with GLS-5310	Change from baseline in binding antibody titers; Change from baseline in T-cell response of antigen-specific interferon - gamma (IFN-γ); Change from baseline in plaque-reduction neutralizing titer(PRNT) in serum	Through 1 year post vaccination
Measure viral load in organs, including blood, of animals administered immune serum from vaccinated individuals and later challenged with SARS-CoV-2.	viral load measurement of blood and major organs	Through 1 year post vaccination
Perform histologic examination of organs of animals administered immune serum from vaccinated individuals and later challenged with SARS-CoV-2.	pathological examination of organs	Through 1 year post vaccination

Collaborators and Investigators

• Sponsor: GeneOne Life Science, Inc.

Study record dates

Study Major Dates

• Study Start (Actual): December 31, 2020
• Primary Completion (Actual): March 3, 2021
• Study Completion (Actual): May 10, 2023

Study Registration Dates

• First Submitted: December 11, 2020
• First Submitted That Met QC Criteria: December 15, 2020
• First Posted (Actual): December 17, 2020

Study Record Updates

• Last Update Posted (Estimated): September 3, 2025
• Last Update Submitted That Met QC Criteria: August 13, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: COVID-19
• Additional Relevant MeSH Terms: Respiratory Tract Infections; Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Lung Diseases; Pneumonia, Viral; Pneumonia; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; COVID-19; Substandard Drugs; Pharmaceutical Preparations; Counterfeit Drugs; GLS-5310 vaccine
• Other Study ID Numbers: CoV2-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No