Immunogenicity and Safety Study of SARS-CoV-2 DNA Vaccine (ICCOV)

NCT05904054 | Completed Phase 2

• 1 other identifier: ICCOV_HK202301
• Study Type: interventional
• Target: 31
• Locations: 1 country
• Sites: 1

Brief Summary

This is an open-labeled, no placebo, Phase IIa clinical trial. The purpose of this study is to evaluate the immunogenicity and safety of one booster vaccine dose of SARS-CoV-2 DNA Vaccine (ICCOV) in adults aged 18 to 75 years who have received two to four dosese of COVID-19 vaccine.

Conditions

COVID-19

Keywords

ICCOV; COVID-19; DNA Vaccine

Outcome Measures

Primary Outcomes (6)

• Frequencies of cross-reactive receptor binding domain (RBD)-specific IFN-γ producing T cells at Day 14

  Frequencies of cross-reactive receptor binding domain (RBD)-specific RBD-specific IFN-γ producing T cells at Day 14 after ICCOV administration compared to baseline (Day 0), as measured by numbers of IFN-γ+ spot-forming unit /1 million PBMC by ELISpot assay.

  Day 14

• Frequencies of cross-reactive receptor binding domain (RBD)-specific IFN-γ producing T cells at Day 28

  Frequencies of cross-reactive receptor binding domain (RBD)-specific RBD-specific IFN-γ producing T cells at Day 28 after ICCOV administration compared to baseline (Day 0), as measured by numbers of IFN-γ+ spot-forming unit /1 million PBMC by ELISpot assay.

  Day 28

• Frequencies of cross-reactive receptor binding domain (RBD)-specific CD4+ T cells at Day 14

  Frequencies of cross-reactive RBD-specific CD4+ T cell responses at Day 14 after ICCOV administration compared to baseline (Day 0), as analyzed by flow cytometry-based intracellular cytokine staining assays.

  Day 14

• Frequencies of cross-reactive receptor binding domain (RBD)-specific CD4+ T cells at Day 28

  Frequencies of cross-reactive RBD-specific CD4+ T cell responses at Day 28 after ICCOV administration compared to baseline (Day 0), as analyzed by flow cytometry-based intracellular cytokine staining assays.

  Day 28

• Frequencies of cross-reactive receptor binding domain (RBD)-specific CD8+ T cells at Day 14

  Frequencies of cross-reactive RBD-specific CD8+ T cell responses at Day 14 after ICCOV administration compared to baseline (Day 0), as analyzed by flow cytometry-based intracellular cytokine staining assays.

  Day 14

• Frequencies of cross-reactive receptor binding domain (RBD)-specific CD8+ T cells at Day 28

  Frequencies of cross-reactive RBD-specific CD8+ T cell responses at Day 28 after ICCOV administration compared to baseline (Day 0), as analyzed by flow cytometry-based intracellular cytokine staining assays.

  Day 28

Secondary Outcomes (3)

• Frequencies of cross-reactive receptor binding domain (RBD)-specific IFN-γ producing T cells at Day 60

  Day 60

• Frequencies of cross-reactive receptor binding domain (RBD)-specific CD8+ T cells at Day 60

  Day 60

• Frequencies of cross-reactive receptor binding domain (RBD)-specific CD4+ T cells at Day 60

  Day 60

Other Outcomes (18)

• Geometric mean titres (GMTs) of neutraliziing antibody against SARS-CoV-2 prototype and epidemic variants

  Day 14

• Geometric mean titres (GMTs) of neutraliziing antibody against SARS-CoV-2 prototype and epidemic variants

  Day 28

• Geometric mean titres (GMTs) of neutraliziing antibody against SARS-CoV-2 prototype and epidemic variants

  Day 60

Study Arms (4)

Adult-CoronaVac® group

EXPERIMENTAL

Aged 18-59 AND received 2 to 4 homologous doses of CoronaVac® at least 3 months prior to enrollment AND without SARS-CoV-2 infection history.

Biological: SARS-CoV-2 DNA Vaccine (ICCOV)

Adult-Comirnaty® group

EXPERIMENTAL

Aged 18-59 AND received 2 to 4 homologous doses of Comirnaty® at least 3 months prior to enrollment AND without SARS-CoV-2 infection history.

Biological: SARS-CoV-2 DNA Vaccine (ICCOV)

Adult-mixed group

EXPERIMENTAL

Aged 18-59 AND received 2 to 4 heterologous doses of CoronaVac® and Comirnaty® at least 3 months prior to enrollment AND without SARS-CoV-2 infection history; OR Aged 18-59 AND received 2 to 4 heterologous doses of CoronaVac® and Comirnaty® at least 3 months prior to enrollment AND recovered from SARS-CoV-2 infection at least 3 months prior to enrollment; OR Aged 18-59 AND received 2 to 4 homologous doses of CoronaVac® or Comirnaty® at least 3 months prior to enrollment AND recovered from SARS-CoV-2 infection at least 3 months prior to enrollment.

Biological: SARS-CoV-2 DNA Vaccine (ICCOV)

Elderly-mixed group

EXPERIMENTAL

Aged 60-75 AND received 2 to 4 heterologous doses of CoronaVac® and Comirnaty® at least 3 months prior to enrollment AND without SARS-CoV-2 infection history; OR Aged 60-75 AND received 2 to 4 heterologous doses of CoronaVac® and Comirnaty® at least 3 months prior to enrollment AND recovered from SARS-CoV-2 infection at least 3 months prior to enrollment; OR Aged 60-75 AND received 2 to 4 homologous doses of CoronaVac® or Comirnaty® at least 3 months prior to enrollment AND without SARS-CoV-2 infection history; OR Aged 60-75 AND received 2 to 4 homologous doses of CoronaVac® or Comirnaty® at least 3 months prior to enrollment AND recovered from SARS-CoV-2 infection at least 3 months prior to enrollment.

Biological: SARS-CoV-2 DNA Vaccine (ICCOV)

Interventions

SARS-CoV-2 DNA Vaccine (ICCOV) BIOLOGICAL

The SARS-CoV-2 DNA Vaccine (ICCOV) was developed by Immuno Cure Holding (HK) Limited.The product is a pre-filled syringe or a vial with an extractable volume of 0.5 mL. The unit dose strength is 1 mg/0.5 mL and the dose volume is 1.0 mL/dose.

Also known as: ICCOV

Adult-Comirnaty® group; Adult-CoronaVac® group; Adult-mixed group; Elderly-mixed group

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Able and willing to comply with all study requirements.
• Give informed consent and sign informed consent form (ICF). For subjects who are unable to read or write, the consent must be witnessed by a literate third party not involved in the study.
• BMI in between 18.5 and 30.0 kg/m2 (including upper and lower limits).
• For each group, meet the following criteria regarding age, COVID-19 vaccination history (as confirmed by COVID-19 vaccination records), and SARS-CoV-2 infection history (as confirmed by the investigator according to WHO definitions, Appendix III):
• Group 1: Adult-CoronaVac® group
• \- Aged 18-59 AND received 2 to 4 homologous doses of CoronaVac® at least 3 months prior to enrollment AND without SARS-CoV-2 infection history.
• Group 2: Adult-Comirnaty® group
• \- Aged 18-59 AND received 2 to 4 heterologous doses of CoronaVac® and Comirnaty® at least 3 months prior to enrollment AND without SARS-CoV-2 infection history; OR
• Group 3: Adult-mixed group
• Aged 18-59 AND received 2 to 4 heterologous doses of CoronaVac® and Comirnaty® at least 3 months prior to enrollment AND without SARS-CoV-2 infection history; OR
• Aged 18-59 AND received 2 to 4 heterologous doses of CoronaVac® and Comirnaty® at least 3 months prior to enrollment AND recovered from SARS-CoV-2 infection at least 3 months prior to enrollment; OR
• Aged 18-59 AND received 2 to 4 homologous doses of CoronaVac® or Comirnaty® at least 3 months prior to enrollment AND recovered from SARS-CoV-2 infection at least 3 months prior to enrollment.
• Group 4: Elderly-mixed group
• Aged 60-75 AND received 2 to 4 heterologous doses of CoronaVac® and Comirnaty® at least 3 months prior to enrollment AND without SARS-CoV-2 infection history; OR
• Aged 60-75 AND received 2 to 4 heterologous doses of CoronaVac® and Comirnaty® at least 3 months prior to enrollment AND recovered from SARS-CoV-2 infection at least 3 months prior to enrollment; OR

You may not qualify if:

• Female subjects of childbearing potential with have negative pregnancy test shall be willing to practice continuous effective contraception and not to breastfeed until 12 months after ICCOV administration.
• Nonchildbearing potential is defined as surgically sterile (history of bilateral tubal ligation, bilateral oophorectomy, hysterectomy) or postmenopausal. A follicle-stimulating hormone (FSH) level and the amenorrhea duration (e.g., amenorrhea for ≥ 12 consecutive months prior to screening without an alternative medical cause) may be measured at the discretion of the investigator to confirm postmenopausal status.
• The effective contraceptive methods include sexual abstinence or adequate contraceptive measures such as intrauterine or implanted contraceptive device, oral contraceptives, injected or implanted contraceptives, sustained-release topical contraceptives, condoms (male), diaphragm, and cervical cap, etc.
• Male subjects who are involved in heterosexual sexual activity must agree to practice adequate contraception (as described above) and refrain from donating sperm until 12 months after ICCOV administration.
• Agreement to avoid blood donation during the study.
• Laboratory confirmed SARS-CoV-2 infection, defined by RT-PCR test.
• Fever (oral temperature ≥ 37.5°C/axillary temperature ≥ 37.3°C) on the day of vaccination or within recent 72 hours.
• Medical history of severe acute respiratory syndrome (SARS), middle east respiratory syndrome (MERS) within 12 months, and COVID-19 within 3 months prior to enrollment.
• Abnormal laboratory tests of clinical significance involving hematology, serum biochemistry, coagulation function, or urinalysis as determined by the investigator.
• Females who are pregnant or breastfeeding or those who plan to give birth in coming 12 months (including in female subjects or the female partners of male subjects).
• Participated in other clinical trials and received any other investigational products within 1 month (or 5 half-lives of the drug, whichever is longer) prior to enrollment or plan to receive any other investigational products during the study.
• History of severe allergies to any vaccine or drug, such as urticaria, dyspnea, edema, abdominal pain and other symptoms after administration, especially hypersensitivity to the components of ICCOV.
• Have malignant tumor (except for skin basal cell carcinoma or carcinoma uterine cervix in situ) and immune disease (e.g., human immunodeficiency virus \[HIV\] infection, systemic lupus erythematosus, rheumatoid arthritis, asplenia or splenectomy, severe combined immunodeficiency disorder \[SCID\], and other immune disease that may influence immune response at the investigator's discretion).
• Have other severe and/or uncontrolled conditions, including but not limited to, acute infectious disease, cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, hematology disease, endocrine disorder, psychiatric condition and neurological illness (e.g., Guillain-Barre Syndrome, uncontrolled epilepsy, etc.). Mild/moderate well-controlled comorbidities are allowed to participate as deemed appropriate by the investigator.
• Received any investigational or approved vaccines within 3 months prior to enrollment or plan to receive any other vaccines during the study.

Sponsors & Collaborators

• Immuno Cure 3 Limited: lead
• The University of Hong Kong: collaborator

Study Sites (1)

Gleneagles Hospital Hong Kong

Wong Chuk Hang, Hong Kong

Location

Related Publications (1)

• Wong YC, Hang Ho DH, Zhou R, Zhang R, Woo KF, Cheng WY, Wang T, Du Y, Polly Pang KP, Tai WK, Jin X, Chen Z, Ngai Hung IF. An open-label study on the safety and immunogenicity of a PD-1-enhanced DNA vaccine used as a T cell booster for COVID-19. EBioMedicine. 2025 May;115:105699. doi: 10.1016/j.ebiom.2025.105699. Epub 2025 Apr 16.

  PMID: 40245494 DERIVED

MeSH Terms

Conditions

COVID-19

Condition Hierarchy (Ancestors)

Pneumonia, Viral; Pneumonia; Respiratory Tract Infections; Infections; Virus Diseases; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Lung Diseases; Respiratory Tract Diseases

Study Officials

• Fan-ngai, Ivan Hung, Dr.

  The University of Hong Kong

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 2, 2023
• First Posted: June 15, 2023
• Study Start: June 15, 2023
• Primary Completion: December 31, 2023
• Study Completion: May 31, 2024
• Last Updated: April 30, 2025

Record last verified: 2024-05

Locations

HK (1)