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Immunogenicity & Safety Study of Adenovirus Type 5 (AD5) Based Oral Norovirus Vaccines

A Phase 1b, Open-label, Boost-optimization Study of an Adenoviral- Vector Based Oral Norovirus Vaccine (VXA-G1.1-NN) Expressing GI.1 VP1 Administered Orally to Healthy Adult Volunteers

Status
Completed
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04875676
Acronym
VXA-NVV-105
Enrollment
30
Registered
2021-05-06
Start date
2021-04-30
Completion date
2022-02-16
Last updated
2024-05-22

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Norovirus Infections

Brief summary

To evaluate the immunogenicity of VXA-G1.1-NN with repeat-dose administration at Day 1 and varying boost schedules (Week 4, 8 or 12 post initial dose) in healthy adults aged 18-55, inclusive, and to assess the safety and tolerability of VXA- G1.1-NN with repeat-dose administration at varying boost schedules (Week 4, 8 or 12) in healthy adults aged 18-55, inclusive

Interventions

BIOLOGICALVXA-G1.1-NN

Norovirus GI.1 Norwalk VP1 Vaccine, Oral E1-/E3-Deleted Replication Defective Recombinant Adenovirus 5 with double-stranded RNA Adjuvant

Sponsors

Vaxart
Lead SponsorINDUSTRY

Study design

Allocation
NON_RANDOMIZED
Intervention model
SEQUENTIAL
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 55 Years
Healthy volunteers
Yes

Inclusion criteria

* To be eligible for this study, participants must meet all the following: Age 1. 18 to 55 years old inclusive at the time of signing the Informed Consent Form (ICF). Type of Participants 2. General good health, without significant uncontrolled medical illness, based on medical history, physical examination, vital signs, and clinical laboratories (CBC, chemistry, and urinalysis) as determined by the investigator in consultation with the Research Monitor and Sponsor 3. Body mass index (BMI) between 17 and 35 kg/m2 at screening 4. Available for all planned visits and phone calls, and willing to complete all protocol- defined procedures and assessments (including ability and willingness to swallow multiple small enteric-coated tablets per study dose). Gender and Reproductive Considerations 5. Male or female participants Contraception use by men or women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies. a. Female participants must provide a negative pregnancy test at each required visit and fulfill one of the following criteria: * At least 1 year post-menopausal (defined as amenorrhea for ≥12 consecutive months prior to Screening without an alternative medical cause). * Women under 60 years will need to verify post-menopausal status via a follicle-stimulating hormone (FSH) test if another option to prevent potential pregnancy will not be utilized for 30 days prior to baseline vaccination and until 60 days after the last vaccination. * Surgically sterile * Use of oral, implantable, transdermal or injectable contraceptives for 30 days prior to initial vaccination and until 60 days after the last vaccination. The form of contraception must be approved by the Investigator * A reliable form of contraception must be approved by the Investigator (e.g., double barrier method, Depo-Provera, intrauterine device, Norplant, oral contraceptives, contraceptive patches). * Not be sexually active (abstinent) or be in a relationship with partner who is sterile (must be discussed with site staff and documented). Informed Consent 6. Capable of giving signed informed consent which includes compliance with the requirements and restrictions listed in the ICF and in this protocol.

Exclusion criteria

* The participants must be excluded from participating in the study if they meet any of the following: Medical Conditions 1. Presence of significant uncontrolled medical or psychiatric illness (acute or chronic) including institution of new medical/surgical treatment or significant dose alteration for uncontrolled symptoms or drug toxicity within 3 months of screening and reconfirmed at baseline 2. Cancer, or received treatment for cancer, within past 3 years (excluding basal cell carcinoma or squamous cell carcinoma) 3. Presence of immunosuppression or medical condition possibly associated with impaired immune responsiveness, including diabetes mellitus 1 and 2 4. History of irritable bowel disease or other inflammatory digestive or gastrointestinal condition that could affect the distribution/safety evaluation of an orally administered vaccine targeting the mucosa of the small intestine. Such conditions may include but are not limited to: 1. Esophageal Motility Disorder 2. Malignancy 3. Malabsorption 4. Pancreaticobiliary disorders 5. Irritable bowel syndrome 6. Inflammatory Bowel Disease 7. Surgical Resection 8. GERD 9. Hiatal Hernia 10. Peptic Ulcer (History of cholecystectomy is not exclusionary) 5. History of any form of angioedema 6. History of serious reactions to any vaccination such as anaphylaxis, respiratory problems, hives or abdominal pain 7. Diagnosed bleeding disorder or significant bruising or bleeding difficulties that could make blood draws problematic 8. Any condition that resulted in the absence or removal of the spleen 9. Acute disease within 72 hours prior to vaccination defined as the presence of a moderate or severe illness (as determined by the Investigator through medical history and physical exam). (Assessment may be repeated during screening period.) 10. Presence of a fever ≥ 38oC measured orally at baseline (Assessment may be repeated during screening period) 11. Any significant hospitalization within the last year which in the opinion of the Investigator or Sponsor could interfere with study participation. 12. Any other condition that in the clinical judgment of the investigator would jeopardize the safety or rights of a participant taking in the study, would render the participant unable to comply with the protocol or would interfere with the evaluation of the study endpoints Diagnostic Assessments 13. Positive human immunodeficiency virus (HIV), Hepatitis B surface antigen (HBsAg) or hepatitis C virus (HCV) tests at the screening visit 14. Positive urine drug screen for drugs of abuse at screening 15. Positive breath or urine alcohol test at screening and baseline Prior/Concurrent Therapy 16. Receipt of a licensed vaccine within 14 days prior to baseline vaccination or planned administration during the study active period (4 weeks post each study vaccination). 17. Use of antibiotics, proton pump inhibitors, H2 blockers or antacids within 7 days prior to study drug administration or planned use during the active study period 18. Use of medications known to affect the immune function (e.g., systemic corticosteroids and others) within 2 weeks before study drug administration or planned use during the active study period 19. Daily use of nonsteroidal anti-inflammatory drugs within 7 days prior to study drug administration or planned use during the active study period 20. Administration of any investigational vaccine, drug or device within 8 weeks preceding study drug administration (Day 1), or planned use within the duration of the study Other Exclusions 21. Donation or use of blood or blood products within 30 days prior to study drug administration or planned donation during the active study period 22. History of drug, alcohol or chemical abuse within 1 year of screening 23. History of hypersensitivity or allergic reaction to any component of the investigational vaccine, including but not limited to fish gelatin

Design outcomes

Primary

MeasureTime frameDescription
Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) AssayDay 1 (Initial Vaccination) through Day 8 post boost (Second Vaccination)Comparison of VPI specific immunoglobin A (IgA) ASC levels between the 3 study cohorts by enzyme-linked immunospot (ELISpot) assay
Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) AssayDay 1 (Initial Vaccination) through Day 29 post boost (Second Vaccination)Comparison of subjects with a ≥2-, 3- or 4-fold increase over baseline titer of GI.1 histo-blood group antigen (HBGA) blocking antibodies (BT50) levels between the 3 study cohorts.
VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) AssayDay 1 (Initial Vaccination) through Day 29 post boost (Second Vaccination)Comparison of VPI specific immunoglobin A (IgA) ASC levels by Mesoscale Discovery (MSD) assay between the 3 study cohorts

Secondary

MeasureTime frameDescription
Solicited Symptoms of ReactogenicityDay 1 (Vaccination) to Day 8 post each vaccinationComparison of frequency, duration, and severity of solicited symptom events in participants

Other

MeasureTime frameDescription
Unsolicited Adverse Events (AEs)Day 1 (Vaccine) through 28 days following boost (Second Vaccination)Comparison of the frequency, duration, and severity of unsolicited AEs and serious AEs (SAEs) including AEs of Special Interest (AESIs) and new onsets of chronic illness (NOCIs) in participants
Long-term SafetyDay 1 (Vaccine) through 6 months following boost (Second Vaccination)Frequency, duration, and severity of all SAEs, AESIs and NOCIs through 6 months after last vaccination.

Countries

United States

Participant flow

Participants by arm

ArmCount
Cohort 1 (4-week Boost Vaccination)
(4-week boost vaccination) 10 subjects will receive two doses of 1x10 log10 IU ± 0.5 log at Day 1 and Week 4 VXA-G1.1-NN: Norovirus GI.1 Norwalk VP1 Vaccine, Oral E1-/E3-Deleted Replication Defective Recombinant Adenovirus 5 with double-stranded RNA Adjuvant
10
Cohort 2 (8-week Boost Vaccination)
(8-week boost vaccination) 10 subjects will receive two doses of 1x10 log10 IU± 0.5 log at Day 1 and Week 8 VXA-G1.1-NN: Norovirus GI.1 Norwalk VP1 Vaccine, Oral E1-/E3-Deleted Replication Defective Recombinant Adenovirus 5 with double-stranded RNA Adjuvant
10
Cohort 3 (12-week Boost Vaccination)
(12-week boost vaccination) 10 subjects will receive two doses of 1x10 log10 IU± 0.5 log at Day 1 and Week 12 VXA-G1.1-NN: Norovirus GI.1 Norwalk VP1 Vaccine, Oral E1-/E3-Deleted Replication Defective Recombinant Adenovirus 5 with double-stranded RNA Adjuvant
10
Total30

Withdrawals & dropouts

PeriodReasonFG000FG001FG002
Overall StudyLost to Follow-up100

Baseline characteristics

CharacteristicCohort 1 (4-week Boost Vaccination)Cohort 2 (8-week Boost Vaccination)Cohort 3 (12-week Boost Vaccination)Total
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
10 Participants10 Participants10 Participants30 Participants
Age, Continuous43.2 years
STANDARD_DEVIATION 7.42
35.4 years
STANDARD_DEVIATION 9.97
34.9 years
STANDARD_DEVIATION 10.09
37.8 years
STANDARD_DEVIATION 9.72
BMI28.27 kg/m^2
STANDARD_DEVIATION 3.248
27.94 kg/m^2
STANDARD_DEVIATION 4.94
27.32 kg/m^2
STANDARD_DEVIATION 3.917
27.84 kg/m^2
STANDARD_DEVIATION 3.971
Ethnicity (NIH/OMB)
Hispanic or Latino
3 Participants3 Participants3 Participants9 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
7 Participants7 Participants7 Participants21 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants
Height163.23 centimeter
STANDARD_DEVIATION 7.236
175.63 centimeter
STANDARD_DEVIATION 7.85
166.22 centimeter
STANDARD_DEVIATION 10.734
168.36 centimeter
STANDARD_DEVIATION 10.001
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
5 Participants3 Participants3 Participants11 Participants
Race (NIH/OMB)
Black or African American
2 Participants2 Participants0 Participants4 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
3 Participants5 Participants7 Participants15 Participants
Region of Enrollment
United States
10 participants10 participants10 participants30 participants
Sex: Female, Male
Female
4 Participants7 Participants4 Participants15 Participants
Sex: Female, Male
Male
6 Participants3 Participants6 Participants15 Participants
Vaccinated for COVID-19
No
2 Participants4 Participants7 Participants13 Participants
Vaccinated for COVID-19
Yes - Johnson & Johnson
0 Participants0 Participants0 Participants0 Participants
Vaccinated for COVID-19
Yes - Moderna
4 Participants3 Participants0 Participants7 Participants
Vaccinated for COVID-19
Yes - Other
0 Participants0 Participants0 Participants0 Participants
Vaccinated for COVID-19
Yes - Pfizer-BioNTech
4 Participants3 Participants3 Participants10 Participants
Weight75.22 kilogram
STANDARD_DEVIATION 9.359
86.99 kilogram
STANDARD_DEVIATION 20.457
75.54 kilogram
STANDARD_DEVIATION 13.36
79.25 kilogram
STANDARD_DEVIATION 15.603

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
0 / 100 / 100 / 10
other
Total, other adverse events
6 / 103 / 106 / 10
serious
Total, serious adverse events
0 / 101 / 100 / 10

Outcome results

Primary

Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay

Comparison of subjects with a ≥2-, 3- or 4-fold increase over baseline titer of GI.1 histo-blood group antigen (HBGA) blocking antibodies (BT50) levels between the 3 study cohorts.

Time frame: Day 1 (Initial Vaccination) through Day 29 post boost (Second Vaccination)

Population: 1 subject received 1 dose only (8-week boost cohort)

ArmMeasureGroupValue (GEOMETRIC_MEAN)
Cohort 1 (4-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post First Dose: GMC (geometric mean concentration)52.7 10^6 AU/mL
Cohort 1 (4-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) AssayDay of First Dose: GMC (geometric mean concentration)29.9 10^6 AU/mL
Cohort 1 (4-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post Second Dose: GMC (geometric mean concentration)74.5 10^6 AU/mL
Cohort 2 (8-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post First Dose: GMC (geometric mean concentration)69.5 10^6 AU/mL
Cohort 2 (8-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) AssayDay of First Dose: GMC (geometric mean concentration)27.9 10^6 AU/mL
Cohort 2 (8-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post Second Dose: GMC (geometric mean concentration)54.0 10^6 AU/mL
Cohort 3 (12-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) AssayDay of First Dose: GMC (geometric mean concentration)21.1 10^6 AU/mL
Cohort 3 (12-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post Second Dose: GMC (geometric mean concentration)64.9 10^6 AU/mL
Cohort 3 (12-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post First Dose: GMC (geometric mean concentration)54.9 10^6 AU/mL
Primary

Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay

Comparison of GI.1 histo-blood group antigen (HBGA) blocking antibodies (BT50) levels between the 3 study cohorts

Time frame: Day 1 (Initial Vaccination) through Day 29 post boost (Second Vaccination)

Population: 1 subject received 1 dose only (8-week boost cohort)

ArmMeasureGroupValue (GEOMETRIC_MEAN)
Cohort 1 (4-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post First Dose: GMFR (geometric mean fold rise)1.8 Fold Rise
Cohort 1 (4-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post Second Dose: GMFR (geometric mean fold rise)2.5 Fold Rise
Cohort 2 (8-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post First Dose: GMFR (geometric mean fold rise)2.5 Fold Rise
Cohort 2 (8-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post Second Dose: GMFR (geometric mean fold rise)2.4 Fold Rise
Cohort 3 (12-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post First Dose: GMFR (geometric mean fold rise)2.6 Fold Rise
Cohort 3 (12-week Boost Vaccination)Norovirus G1.1 Histo-blood Group Antigen (HBGA) Blocking Antibodies (BT50) Assay28-Days post Second Dose: GMFR (geometric mean fold rise)3.1 Fold Rise
Primary

Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) Assay

Comparison of VPI specific immunoglobin A (IgA) ASC levels between the 3 study cohorts by enzyme-linked immunospot (ELISpot) assay

Time frame: Day 1 (Initial Vaccination) through Day 8 post boost (Second Vaccination)

Population: 1 subject received 1 dose only (8-week boost cohort)

ArmMeasureGroupValue (MEAN)
Cohort 1 (4-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) AssayFirst Dose1.3 Spot Forming Units per 10^6 PBMC
Cohort 1 (4-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) Assay7-Days post First Dose127.6 Spot Forming Units per 10^6 PBMC
Cohort 1 (4-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) AssaySecond Dose2 Spot Forming Units per 10^6 PBMC
Cohort 1 (4-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) Assay7-Days post Second Dose25.5 Spot Forming Units per 10^6 PBMC
Cohort 2 (8-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) Assay7-Days post Second Dose68.8 Spot Forming Units per 10^6 PBMC
Cohort 2 (8-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) AssayFirst Dose0.5 Spot Forming Units per 10^6 PBMC
Cohort 2 (8-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) AssaySecond Dose2.1 Spot Forming Units per 10^6 PBMC
Cohort 2 (8-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) Assay7-Days post First Dose214.3 Spot Forming Units per 10^6 PBMC
Cohort 3 (12-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) Assay7-Days post Second Dose132.1 Spot Forming Units per 10^6 PBMC
Cohort 3 (12-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) Assay7-Days post First Dose327.5 Spot Forming Units per 10^6 PBMC
Cohort 3 (12-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) AssaySecond Dose2.3 Spot Forming Units per 10^6 PBMC
Cohort 3 (12-week Boost Vaccination)Viral-capsid Protein 1 (VP1)-Specific Antibody Secreting Cells (ASC) by Enzyme-linked Immunospot (ELISpot) AssayFirst Dose0.3 Spot Forming Units per 10^6 PBMC
Primary

VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay

Comparison of VPI specific immunoglobin A (IgA) ASC levels by Mesoscale Discovery (MSD) assay between the 3 study cohorts

Time frame: Day 1 (Initial Vaccination) through Day 29 post boost (Second Vaccination)

Population: 1 subject received 1 dose only (8-week boost cohort)

ArmMeasureGroupValue (GEOMETRIC_MEAN)
Cohort 1 (4-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the First Dose: GMFR (geometric mean fold rise)4.6 Fold rise
Cohort 1 (4-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the Second Dose: GMFR (geometric mean fold rise)3.3 Fold rise
Cohort 2 (8-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the First Dose: GMFR (geometric mean fold rise)8.9 Fold rise
Cohort 2 (8-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the Second Dose: GMFR (geometric mean fold rise)5.4 Fold rise
Cohort 3 (12-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the First Dose: GMFR (geometric mean fold rise)11.3 Fold rise
Cohort 3 (12-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the Second Dose: GMFR (geometric mean fold rise)8.9 Fold rise
Primary

VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay

Comparison of VPI specific immunoglobin A (IgA) ASC levels by Mesoscale Discovery (MSD) assay between the 3 study cohorts

Time frame: Day 1 (Initial Vaccination) through Day 29 post boost (Second Vaccination)

Population: 1 subject received 1 dose only (8-week boost cohort)

ArmMeasureGroupValue (GEOMETRIC_MEAN)
Cohort 1 (4-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the First Dose: GMC (geometric mean concentration)2.1 10^6 AU/mL
Cohort 1 (4-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) AssayFirst Dose: GMC (geometric mean concentration)0.5 10^6 AU/mL
Cohort 1 (4-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the Second Dose: GMC (geometric mean concentration)1.5 10^6 AU/mL
Cohort 2 (8-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the First Dose: GMC (geometric mean concentration)2.6 10^6 AU/mL
Cohort 2 (8-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) AssayFirst Dose: GMC (geometric mean concentration)0.3 10^6 AU/mL
Cohort 2 (8-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the Second Dose: GMC (geometric mean concentration)1.2 10^6 AU/mL
Cohort 3 (12-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) AssayFirst Dose: GMC (geometric mean concentration)0.2 10^6 AU/mL
Cohort 3 (12-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the Second Dose: GMC (geometric mean concentration)1.7 10^6 AU/mL
Cohort 3 (12-week Boost Vaccination)VP1 Serum Immunoglobin G (IgG) by Mesoscale Discovery (MSD) Assay28-Days post the First Dose: GMC (geometric mean concentration)2.1 10^6 AU/mL
Secondary

Solicited Symptoms of Reactogenicity

Comparison of frequency, duration, and severity of solicited symptom events in participants

Time frame: Day 1 (Vaccination) to Day 8 post each vaccination

Population: Subjects with Solicited Symptoms

ArmMeasureGroupValue (NUMBER)
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityAnorexia: Total1 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityHeadache: Total5 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityDiarrhea: Moderate1 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityAbdominal Pain: Moderate0 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityHeadache: Mild4 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityNausea: Moderate0 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityAbdominal Pain: Mild2 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityHeadache: Moderate1 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityMalaise/Fatigue: Mild2 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityAbdominal Pain: Total2 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityMyalgia: Total2 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityDiarrhea: Mild2 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityMyalgi: Moderate0 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityMyalgia: Mild2 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityVomiting: Total1 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityNausea: Total1 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityDiarrhea: Total3 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityAnorexia: Mild1 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityAnorexia: Moderate0 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityFever: Total0 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityMalaise/Fatigue: Total3 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityVomiting: Moderate0 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityFever: Mild0 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityNausea: Mild1 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityVomiting: Mild1 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityFever: Moderate0 events
Cohort 1 (4-week Boost Vaccination)Solicited Symptoms of ReactogenicityMalaise/Fatigue: Moderate1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityMyalgia: Mild0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityAnorexia: Moderate0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityNausea: Total0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityNausea: Mild0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityNausea: Moderate0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityVomiting: Total0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityAnorexia: Mild0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityFever: Total0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityFever: Mild0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityFever: Moderate0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityHeadache: Total1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityHeadache: Mild1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityHeadache: Moderate0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityMyalgia: Total1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityMyalgi: Moderate1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityAbdominal Pain: Total2 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityAbdominal Pain: Mild1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityAbdominal Pain: Moderate1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityAnorexia: Total0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityVomiting: Mild0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityVomiting: Moderate0 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityDiarrhea: Total2 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityDiarrhea: Mild1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityDiarrhea: Moderate1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityMalaise/Fatigue: Total1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityMalaise/Fatigue: Mild1 events
Cohort 2 (8-week Boost Vaccination)Solicited Symptoms of ReactogenicityMalaise/Fatigue: Moderate0 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityFever: Moderate0 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityNausea: Total2 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityAnorexia: Total0 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityFever: Mild0 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityAnorexia: Mild0 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityVomiting: Mild2 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityFever: Total0 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityMalaise/Fatigue: Total3 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityVomiting: Moderate0 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityVomiting: Total2 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityAnorexia: Moderate0 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityDiarrhea: Total4 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityNausea: Moderate0 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityMalaise/Fatigue: Moderate1 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityMyalgia: Mild2 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityMyalgia: Total2 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityDiarrhea: Mild3 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityMyalgi: Moderate0 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityHeadache: Moderate2 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityNausea: Mild2 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityAbdominal Pain: Total3 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityHeadache: Mild3 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityMalaise/Fatigue: Mild2 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityAbdominal Pain: Mild2 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityHeadache: Total5 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityDiarrhea: Moderate1 events
Cohort 3 (12-week Boost Vaccination)Solicited Symptoms of ReactogenicityAbdominal Pain: Moderate1 events
Other Pre-specified

Long-term Safety

Frequency, duration, and severity of all SAEs, AESIs and NOCIs through 6 months after last vaccination.

Time frame: Day 1 (Vaccine) through 6 months following boost (Second Vaccination)

Other Pre-specified

Unsolicited Adverse Events (AEs)

Comparison of the frequency, duration, and severity of unsolicited AEs and serious AEs (SAEs) including AEs of Special Interest (AESIs) and new onsets of chronic illness (NOCIs) in participants

Time frame: Day 1 (Vaccine) through 28 days following boost (Second Vaccination)

Population: Subjects with Any Unsolicited AEs

ArmMeasureGroupValue (NUMBER)
Cohort 1 (4-week Boost Vaccination)Unsolicited Adverse Events (AEs)Toothache (Mild)0 events
Cohort 1 (4-week Boost Vaccination)Unsolicited Adverse Events (AEs)Syncope (Mild)1 events
Cohort 1 (4-week Boost Vaccination)Unsolicited Adverse Events (AEs)COVID-19 Pneumonia (Severe)0 events
Cohort 2 (8-week Boost Vaccination)Unsolicited Adverse Events (AEs)Syncope (Mild)0 events
Cohort 2 (8-week Boost Vaccination)Unsolicited Adverse Events (AEs)Toothache (Mild)0 events
Cohort 2 (8-week Boost Vaccination)Unsolicited Adverse Events (AEs)COVID-19 Pneumonia (Severe)1 events
Cohort 3 (12-week Boost Vaccination)Unsolicited Adverse Events (AEs)Syncope (Mild)1 events
Cohort 3 (12-week Boost Vaccination)Unsolicited Adverse Events (AEs)COVID-19 Pneumonia (Severe)0 events
Cohort 3 (12-week Boost Vaccination)Unsolicited Adverse Events (AEs)Toothache (Mild)1 events

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026