Trial Outcomes & Findings for GLS-5310 Vaccine for the Prevention of SARS-CoV-2 (COVID-19) (NCT NCT04673149)
NCT ID: NCT04673149
Last Updated: 2025-09-03
Results Overview
Recruitment status
COMPLETED
Study phase
PHASE1/PHASE2
Target enrollment
171 participants
Primary outcome timeframe
Through 48 weeks post vaccination
Results posted on
2025-09-03
Participant Flow
Participant milestones
| Measure |
GLS-5310 0.6mg [Group 1a]
0.6mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1b]
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1c]
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 12.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
Placebo [Group 2a]
Placebo will be intradermally administered on Day 0 and Week 8 (or Week 12).
Placebo: Placebo
|
GLS-5310 1.2mg [Group 2b]
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8 (or Week 12).
GLS-5310: GLS-5310 DNA plasmid vaccine
|
|---|---|---|---|---|---|
|
Overall Study
STARTED
|
15
|
15
|
15
|
42
|
84
|
|
Overall Study
COMPLETED
|
15
|
15
|
15
|
26
|
77
|
|
Overall Study
NOT COMPLETED
|
0
|
0
|
0
|
16
|
7
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
GLS-5310 Vaccine for the Prevention of SARS-CoV-2 (COVID-19)
Baseline characteristics by cohort
| Measure |
GLS-5310 0.6mg [Group 1a]
n=15 Participants
0.6mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1b]
n=15 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1c]
n=15 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 12.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
Placebo [Group 2a]
n=42 Participants
Placebo will be intradermally administered on Day 0 and Week 8 (or Week 12).
Placebo: Placebo
|
GLS-5310 1.2mg [Group 2b]
n=84 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8 (or Week 12).
GLS-5310: GLS-5310 DNA plasmid vaccine
|
Total
n=171 Participants
Total of all reporting groups
|
|---|---|---|---|---|---|---|
|
Age, Customized
Age 19-66
|
15 Participants
n=5 Participants
|
15 Participants
n=7 Participants
|
15 Participants
n=5 Participants
|
42 Participants
n=4 Participants
|
80 Participants
n=21 Participants
|
167 Participants
n=10 Participants
|
|
Age, Customized
Age >66-85
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
4 Participants
n=21 Participants
|
4 Participants
n=10 Participants
|
|
Sex: Female, Male
Female
|
9 Participants
n=5 Participants
|
9 Participants
n=7 Participants
|
14 Participants
n=5 Participants
|
31 Participants
n=4 Participants
|
64 Participants
n=21 Participants
|
127 Participants
n=10 Participants
|
|
Sex: Female, Male
Male
|
6 Participants
n=5 Participants
|
6 Participants
n=7 Participants
|
1 Participants
n=5 Participants
|
11 Participants
n=4 Participants
|
20 Participants
n=21 Participants
|
44 Participants
n=10 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
0 Participants
n=10 Participants
|
|
Race (NIH/OMB)
Asian
|
15 Participants
n=5 Participants
|
15 Participants
n=7 Participants
|
15 Participants
n=5 Participants
|
42 Participants
n=4 Participants
|
84 Participants
n=21 Participants
|
171 Participants
n=10 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
0 Participants
n=10 Participants
|
|
Race (NIH/OMB)
Black or African American
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
0 Participants
n=10 Participants
|
|
Race (NIH/OMB)
White
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
0 Participants
n=10 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
0 Participants
n=10 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
0 Participants
n=10 Participants
|
PRIMARY outcome
Timeframe: Through 48 weeks post vaccinationOutcome measures
| Measure |
GLS-5310 0.6mg [Group 1a]
n=15 Participants
0.6mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1b]
n=15 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1c]
n=15 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 12.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
Placebo [Group 2a]
n=42 Participants
Placebo will be intradermally administered on Day 0 and Week 8 (or Week 12).
Placebo: Placebo
|
GLS-5310 1.2mg [Group 2b]
n=84 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8 (or Week 12).
GLS-5310: GLS-5310 DNA plasmid vaccine
|
|---|---|---|---|---|---|
|
Number of Serious Adverse Events
|
0 serious adverse events
|
0 serious adverse events
|
0 serious adverse events
|
0 serious adverse events
|
0 serious adverse events
|
SECONDARY outcome
Timeframe: Post vaccination Visit 4 (4 weeks after week 8 or week 12 vaccination)Outcome measures
| Measure |
GLS-5310 0.6mg [Group 1a]
n=15 Participants
0.6mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1b]
n=15 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1c]
n=15 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 12.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
Placebo [Group 2a]
n=38 Participants
Placebo will be intradermally administered on Day 0 and Week 8 (or Week 12).
Placebo: Placebo
|
GLS-5310 1.2mg [Group 2b]
n=75 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8 (or Week 12).
GLS-5310: GLS-5310 DNA plasmid vaccine
|
|---|---|---|---|---|---|
|
Number of Participants With Positive T Cell Responses Induced by GLS-5310
|
14 Participants
|
12 Participants
|
14 Participants
|
14 Participants
|
24 Participants
|
SECONDARY outcome
Timeframe: Post vaccination Visit 4 (4 weeks after week 8 or week 12 vaccination)Outcome measures
| Measure |
GLS-5310 0.6mg [Group 1a]
n=15 Participants
0.6mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1b]
n=15 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1c]
n=15 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 12.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
Placebo [Group 2a]
n=38 Participants
Placebo will be intradermally administered on Day 0 and Week 8 (or Week 12).
Placebo: Placebo
|
GLS-5310 1.2mg [Group 2b]
n=75 Participants
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8 (or Week 12).
GLS-5310: GLS-5310 DNA plasmid vaccine
|
|---|---|---|---|---|---|
|
Number of Participants With Positive Neutralizing Antibody Responses Induced by GLS-5310
|
4 Participants
|
5 Participants
|
6 Participants
|
2 Participants
|
7 Participants
|
Adverse Events
GLS-5310 0.6mg [Group 1a]
Serious events: 0 serious events
Other events: 15 other events
Deaths: 0 deaths
GLS-5310 1.2mg [Group 1b]
Serious events: 0 serious events
Other events: 15 other events
Deaths: 0 deaths
GLS-5310 1.2mg [Group 1c]
Serious events: 0 serious events
Other events: 15 other events
Deaths: 0 deaths
Placebo [Group 2a]
Serious events: 0 serious events
Other events: 33 other events
Deaths: 0 deaths
GLS-5310 1.2mg [Group 2b]
Serious events: 0 serious events
Other events: 82 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
GLS-5310 0.6mg [Group 1a]
n=15 participants at risk
0.6mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1b]
n=15 participants at risk
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
GLS-5310 1.2mg [Group 1c]
n=15 participants at risk
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 12.
GLS-5310: GLS-5310 DNA plasmid vaccine
|
Placebo [Group 2a]
n=44 participants at risk
Placebo will be intradermally administered on Day 0 and Week 8 (or Week 12).
Placebo: Placebo
|
GLS-5310 1.2mg [Group 2b]
n=82 participants at risk
1.2mg of GLS-5310 will be intradermally administered on Day 0 and Week 8 (or Week 12).
GLS-5310: GLS-5310 DNA plasmid vaccine
|
|---|---|---|---|---|---|
|
General disorders
Injection site erythyma
|
60.0%
9/15 • Number of events 9 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
86.7%
13/15 • Number of events 13 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
93.3%
14/15 • Number of events 14 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
34.1%
15/44 • Number of events 15 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
67.1%
55/82 • Number of events 55 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
|
General disorders
Injection site pruritus
|
60.0%
9/15 • Number of events 9 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
73.3%
11/15 • Number of events 11 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
66.7%
10/15 • Number of events 10 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
11.4%
5/44 • Number of events 5 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
40.2%
33/82 • Number of events 33 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
|
General disorders
Injection site edema
|
26.7%
4/15 • Number of events 4 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
66.7%
10/15 • Number of events 10 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
46.7%
7/15 • Number of events 7 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
11.4%
5/44 • Number of events 5 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
34.1%
28/82 • Number of events 28 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
|
General disorders
Injection site pain
|
6.7%
1/15 • Number of events 1 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
13.3%
2/15 • Number of events 2 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
20.0%
3/15 • Number of events 3 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
18.2%
8/44 • Number of events 8 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
25.6%
21/82 • Number of events 21 • Adverse Event data were collected from Week 0 through Week 48.
Adverse events were graded according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials guidelines that were issued by the Food and Drug Administration in September 2007.
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place