Safety of a Single Dose of COMVIGEN VaccinePhase 2NCT05930730
Immunogenicity and Safety of Comvigen (Bivalent) Vaccine
A Phase 2 study testing Comvigen (Bivalent, ChulaCov19 BNA159.2) and BIVALENT Pfizer/BNT vaccine in people with Safety of a Single Dose of COMVIGEN Vaccine and Reactogenicity of a Single Dose of COMVIGEN Vaccine, run by Chulalongkorn University at 2 sites in Thailand.
Trial summary
This study will assess the safety, reactogenicity and immunogenicity of a single dose of Comvigen (Bivalent, ChulaCov19 BNA159.2) vaccine or BIVALENT Pfizer/BNT vaccine as a booster among healthy males and non-pregnant females aged 18-64 years after receiving a previous booster dose of any approved mRNA COVID-19… Read more about this study
- Who is it for?
- Ages 18 to 64 yearsHealthy volunteers can take part
- Conditions the study is for
- Safety of a Single Dose of COMVIGEN Vaccine, Reactogenicity of a Single Dose of COMVIGEN Vaccine, Immunogenicity of a Single Dose of COMVIGEN Vaccine
- What is being tested?
- Comvigen (Bivalent, ChulaCov19 BNA159.2) and BIVALENT Pfizer/BNT vaccine
- Type of treatment
- Vaccines
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 450 participants
- Where
- 2 sitesThailand
- Study dates
- 9 Oct 2023to Feb 2024
- Phase
- Phase 2
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 64 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Participants who meet all the following criteria at Screening are eligible to participate in the study:
- Must be a male or female aged 18 - 64 (inclusive) at the time of enrolment
- Must have completed at least a primary course of 2 doses of any approved COVID-19 vaccine which the last dose have to be mRNA vaccine and completed the last doser 3 months or more
- Must be able to communicate effectively with study personnel and considered reliable, willing, and cooperative in terms of compliance with the protocol requirements
- Participants must sign the written informed consent form prior to undertaking any protocol-related procedures
- SARS-CoV-2 rapid antigen test is negative at Day 1 (the day of receiving the study booster dose)
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- Does not intend to receive any other authorized/approved COVID-19 vaccine at the time of enrolment and up to 3 months of the study
- Males must be surgically sterile (>30 days since vasectomy with no viable sperm), practice true abstinence or, if engaged in sexual relations with a female of child-bearing potential, the participants and their partner must use an acceptable, highly effective, double-barrier contraceptive method* from Screening and for a period of at least 60 days after vaccination
- A female participant is eligible if she is not pregnant, or breastfeeding indicated by one of the following conditions:
- With childbearing potential (WOCBP): she agrees to use an effective contraceptive method or abstinence from at least 4 weeks prior to the study intervention administration until at least 12 weeks after the study intervention administration, or
- With non-childbearing potential. To be considered of non-childbearing potential, a female must be post-menopausal for at least 1 year or surgically sterile
- Participants must be in general good health* based on medical history and physical examination, as determined by the PI at Screening.
- Participants must agree to refrain from donating blood, plasma, ova, sperm, or organs during the whole study.
Who cannot join
- Participants who meet any of the following criteria are not eligible to participate in the study:
- History of a systemic hypersensitivity or life-threatening reaction to a vaccine containing any of the same or similar substances.
- History of test-confirmed by PCR or rapid antigen test to SARS-CoV-2 COVID-19 infection within 3 months prior to randomisation.
- Presence of clinically significant medical history*, unstable chronic or acute disease that, in the opinion of the PI, may increase the risk of exposure to the investigational vaccine
- History of having any significant side effects after receipt of any other COVID-19 vaccine eg. endocarditis, pericarditis or myocarditis. History of any severe reactogenic side effects or other medical illness that were thought to be associated with vaccine.
- Presence of an acute illness* or with fever at 38.00 C or more within 72 hours prior to vaccination.
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- Bleeding disorders or taking an anticoagulant or anti-platelet agent that may contraindicate for intramuscular injection based on Investigator's judgment
- Inadequate venous access to allow the collection of blood samples.
- Received any prophylactic or therapeutic vaccine, biologic product, device or blood product, within 4 weeks of vaccination or 5 half-lives (whichever is longer) or anticipate doing so in the follow-up period defined for this study. For influenza vaccine, however, can be administered up to 14 days prior to randomization and following visit 3 (Day 29+3) after blood sample collection.
- History of ever had an anaphylaxis reaction to food, medication, or vaccination.
- Participant is immunosuppressed as caused by disease or immunosuppressive therapy or anticipated need to use of any chemotherapy or immunosuppressive agents* within the next 6 months.
- Participation in any of the other investigational trials of vaccines, therapeutic, or medical devices 12 weeks before or during the 6 months of this study.
- Received immunoglobulins and/or any blood or blood products within 3 months before vaccination day or plans to receive any blood or blood products at any time during the study.
Trial locations and contacts
2 sites in 1 country.
Thailand2 sites, 2 recruiting
- Recruiting
Department of Pediatric, Faculty of Medicine, Chulalongkorn University
Bangkok, 10330
Watsamon Jantarabenjakul, MD, +66 818276255, Watsamon.J@chula.ac.th
Watsamon Jantarabenjakul, MD
- Recruiting
HIV-NAT, Thai Red Cross - AIDS Research Centre
Bangkok, 10330
Sivaporn Gatechompol, MD, +66 85-048-5053, sivaporn.k@hivnat.org
Sivaporn Gatechompol, MD
About this study
Official title: A Phase 2, Non-inferiority, Open-label, Randomized Controlled Study to Evaluate the Immunogenicity and Safety of Comvigen (Bivalent) Vaccine as a Booster Dose in Adults Who Have Received a Previous Booster Dose of an Approved COVID-19 Vaccine
This study will assess the safety, reactogenicity and immunogenicity of a single dose of Comvigen (Bivalent, ChulaCov19 BNA159.2) vaccine or BIVALENT Pfizer/BNT vaccine as a booster among healthy males and non-pregnant females aged 18-64 years after receiving a previous booster dose of any approved mRNA COVID-19 vaccine for more than 3 months. The results of Combiven will be compared to BIVALENT Pfizer/BNT vaccine.
Read the detailed description
This is a phase II, non-inferiority, multicenter randomized open-label trial in which 450 healthy males and non-pregnant females, aged 18-64 years, will be recruited from multi-sites in Thailand. The randomization will be a 2:1 design to receive either Comvigen (Bivalent, ChulaCov19 BNA159.2) vaccine or BIVALENT Pfizer/BNT vaccine. This clinical trial is designed to assess the safety, reactogenicity and immunogenicity of a single dose of COMVIGEN at 50 ug, as a booster dose, given at 3 months and above after receipt of a previous booster dose of any approved mRNA COVID-19 vaccine. The estimated sample size would also allow a comparison between a booster dose, Comvigen (Bivalent, ChulaCov19 BNA159.2) vaccine at 50 ug to Comirnaty, BIVALENT of Pfizer/BNT Bivalent vaccine at 30 ug dose.
- Conditions
- Safety of a Single Dose of COMVIGEN Vaccine, Reactogenicity of a Single Dose of COMVIGEN Vaccine, Immunogenicity of a Single Dose of COMVIGEN Vaccine, Safety of a Single Dose of BIVALENT Pfizer/BNT Vaccine, Reactogenicity of a Single Dose of BIVALENT Pfizer/BNT Vaccine, Immunogenicity of a Single Dose of BIVALENT Pfizer/BNT Vaccine
- Being tested
- Comvigen (Bivalent, ChulaCov19 BNA159.2), BIVALENT Pfizer/BNT vaccine
- Keywords
- Non-inferiority study, Open-label, Randomized Controlled Study, Immunogenicity of the booster dose, safety of booster dose, reactogenicity of booster dose, COMVIGEN (Bivalent, ChulaCov19 BNA159.2 vaccine), Pfizer bivalent vaccine (Comirnaty, BIVALENT), mRNA from the ancestral (original) strain, Omicron variant (BA.4/BA.5) of SARS-CoV-2
- Medical subject headings
- Sprains and Strains
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Comvigen (Bivalent, ChulaCov19 BNA159.2)Biological
single dose of COMVIGEN at 50 ug, as a booster dose, given at 3 months and above after receipt of a previous booster dose of any approved mRNA COVID-19 vaccine
BIVALENT Pfizer/BNT vaccineBiological
single dose of BIVALENT of Pfizer/BNT Bivalent vaccine at 30 ug, as a booster dose, given at 3 months and above after receipt of a previous booster dose of any approved mRNA COVID-19 vaccine
| Study group | Role | What they receive |
|---|---|---|
| Comvigen (Bivalent, ChulaCov19 BNA159.2) | Experimental | Not described Receives: Biological: Comvigen (Bivalent, ChulaCov19 BNA159.2) |
| BIVALENT Pfizer/BNT vaccine | Active comparator | Not described Receives: Biological: BIVALENT Pfizer/BNT vaccine |
What is being measured
The primary outcome is the main question the study is designed to answer.
adverse events
Presence of immediate adverse events within 30 minutes after vaccination
Measured: 30 minutes after vaccination
solicited injection site or systemic reactions
Presence of solicited injection site or systemic reactions within 7 days after vaccination
Measured: within 7 days after vaccination
unsolicited adverse events
Presence of unsolicited adverse events within 28 days after vaccination
Measured: within 28 days after vaccination
serious adverse events (SAEs)
Presence of serious adverse events (SAEs) from day 1 to Day 169
Measured: 169 days
medically attended adverse events (MAAEs)
Presence of medically attended adverse events (MAAEs) from day 1 to Day 169
Measured: 169 days
New Onset Chronic Medical Condition (NOCMCs)
Presence of New Onset Chronic Medical Condition (NOCMCs) from day 1 to Day 169
Measured: 169 days
vital signs
Number of participants with abnormal vital signs
Measured: 169 days
vital signs
Percent of participants with abnormal vital signs
Measured: 169 days
clinical changes
Number of participants with abnormal physical examinations finding
Measured: 169 days
clinical changes
Percent of participants with abnormal physical examinations findingexaminations
Measured: 169 days
Geometric mean titers of neutralizing antibody titer
Geometric mean titers of neutralizing antibody titer measured by pseudoviral neutralization assay (psVNT-50) against Omicron BA.4/BA.5 exposed to COMVIGEN (Bivalent) vaccine
Measured: Day 29
Geometric mean titers of neutralizing antibody titer
Geometric mean titers of neutralizing antibody titer measured by pseudoviral neutralization assay (psVNT-50) against wild-type virus exposed to COMVIGEN (Bivalent) vaccine
Measured: Day 29
Geometric mean titers of neutralizing antibody titer
Geometric mean titers of neutralizing antibody titer measured by pseudoviral neutralization assay (psVNT-50) against Omicron BA.4/BA.5 exposed to BIVALENT vaccine
Measured: Day 29
Geometric mean titers of neutralizing antibody titer
Geometric mean titers of neutralizing antibody titer measured by pseudoviral neutralization assay (psVNT-50) against wild-type virus exposed to BIVALENT vaccine
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer against wild-type virus exposed to COMVIGEN (Bivalent) vaccine
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer against Omicron BA.4/BA.5 exposed to COMVIGEN (Bivalent) vaccine
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer against wild-type virus exposed to BIVALENT vaccine
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer against Omicron BA.4/BA.5 exposed to BIVALENT vaccine
Measured: Day 29
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer, psVNT-50 against wild-type virus exposed to COMVIGEN (Bivalent)
Measured: Day 29
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer, psVNT-50 against Omicron BA.4/BA.5 exposed to COMVIGEN (Bivalent)
Measured: Day 29
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer, psVNT-50 against against wild-type virus exposed to BIVALENT vaccine
Measured: Day 29
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer, psVNT-50 against against Omicron BA.4/BA.5 exposed to BIVALENT vaccine
Measured: Day 29
Secondary outcomes (23)
Geometric mean titers of neutralizing antibody titer
Geometric mean titers of neutralizing antibody titer at Day 29 measured by psVNT-50 against other relevant variants of concerns (VOCs)
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer against other relevant VOCs from Day 1 to Day 29
Measured: Day 29
Proportion of participants with at least 4-fold-rise in neutralization antibody titer
Proportion of participants with at least 4-fold-rise in neutralization antibody titer, psVNT-50 against other relevant VOCs from Day 1 to Day 29
Measured: Day 29
Geometric mean titers of neutralizing antibody titer
Geometric mean titers of neutralizing antibody titer at Day 1 measured by live-virus microneutralization assay (micro-VNT-50) against wild-type virus
Measured: Day 1
Geometric mean titers of neutralizing antibody titer
Geometric mean titers of neutralizing antibody titer at Day 29 measured by live-virus microneutralization assay (micro-VNT-50) against wild-type virus
Measured: Day 29
Geometric mean titers of neutralizing antibody titer
Geometric mean titers of neutralizing antibody titer at Day 1 measured by live-virus microneutralization assay (micro-VNT-50) against omicron BA.4/BA.5
Measured: Day 1
Geometric mean titers of neutralizing antibody titer
Geometric mean titers of neutralizing antibody titer at Day 29 measured by live-virus microneutralization assay (micro-VNT-50) against omicron BA.4/BA.5
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of micro-VNT-50
Geometric mean of the fold-rise post-vaccination of micro-VNT-50 against wild-type on Day 29.
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of micro-VNT-50
Geometric mean of the fold-rise post-vaccination of micro-VNT-50 against omicron BA.4/BA.5 virus on Day 29.
Measured: Day 29
Proportion of participants with at least 4-fold-rise in micro-VNT-50
Proportion of participants with at least 4-fold-rise in micro-VNT-50 against wild-type virus on Day 29.
Measured: Day 29
Proportion of participants with at least 4-fold-rise in micro-VNT-50
Proportion of participants with at least 4-fold-rise in micro-VNT-50 against omicron BA.4/BA.5 virus on Day 29.
Measured: Day 29
Geometric mean titers of anti-RBD antibody titer
Geometric mean titers of anti-RBD antibody titer at Day 29 against wild type.
Measured: Day 29
Geometric mean titers of anti-Spike (S) antibody titer
Geometric mean titers of anti-Spike (S) antibody titer at Day 29 against wild type.
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of anti-RBD antibody
Geometric mean of the fold-rise post-vaccination of anti-RBD antibody against wild-type virus at Day 29.
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of anti-S antibody titer
Geometric mean of the fold-rise post-vaccination of anti-S antibody titer against wild-type virus at Day 29.
Measured: Day 29
Proportion of participants with at least 4-fold-rise in anti-RBD
Proportion of participants with at least 4-fold-rise in anti-RBD titer against wild-type virus at Day 29
Measured: Day 29
Proportion of participants with at least 4-fold-rise in anti-RBD
Proportion of participants with at least 4-fold-rise in anti-S antibody titer against wild-type virus at Day 29
Measured: Day 29
Geometric mean of SARS-CoV2-specific T-cell responses
Geometric mean of SARS-CoV2-specific T-cell responses (spot-forming cells or SFC per 1 million PBMCs) measured by IFN gamma-ELISPOT assay against wild-type peptides at day 1
Measured: Day 1
Geometric mean of SARS-CoV2-specific T-cell responses
Geometric mean of SARS-CoV2-specific T-cell responses (spot-forming cells or SFC per 1 million PBMCs) measured by IFN gamma-ELISPOT assay against wild-type peptides at day 29
Measured: Day 29
median number of SARS-CoV2-specific T-cell responses
median number of SARS-CoV2-specific T-cell responses (spot-forming cells or SFC per 1 million PBMCs) measured by IFN gamma-ELISPOT assay against wild-type peptides at day 1
Measured: Day 1
median number of SARS-CoV2-specific T-cell responses
median number of SARS-CoV2-specific T-cell responses (spot-forming cells or SFC per 1 million PBMCs) measured by IFN gamma -ELISPOT assay against wild-type peptides at day 29
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of SARS-CoV2-specific T-cell responses
Geometric mean of the fold-rise post-vaccination of SARS-CoV2-specific T-cell responses (spot-forming cells (SFC) per 1 million PBMCs) measured by IFN gamma-ELISPOT assay against wild-type peptides exposed to COMVIGEN (Bivalent) vaccine on Day 29
Measured: Day 29
Geometric mean of the fold-rise post-vaccination of SARS-CoV2-specific T-cell responses
Geometric mean of the fold-rise post-vaccination of SARS-CoV2-specific T-cell responses (spot-forming cells (SFC) per 1 million PBMCs) measured by IFN gamma-ELISPOT assay against wild-type peptides exposed to BIVALENT vaccine on Day 29
Measured: Day 29
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Jul 2023
- Study start9 Oct 2023
- Primary completionFeb 2024 (estimated)
- Study completionFeb 2024 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Safety of a Single Dose of COMVIGEN VaccineStudies of the same condition, open and under way.
- More trials run by Chulalongkorn UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 450 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Chulalongkorn University
- Sponsor type
- University, hospital or other
- Collaborators
- Thai Red Cross AIDS Research Centre
- Responsible party
- Sponsor
- Investigators
- Watsamon Jantarabenjakul, MD, Principal investigator, Department of Pediatric, Faculty of Medicine, Chulalongkorn University, Bangkok, ThailandSivaporn Gatechompol, MD, Principal investigator, HIVNAT, Thai Red Cross AIDS Research Centre, Bangkok, Thailand
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05930730
- Sponsor's protocol ID
- ChulaVac 006
- Status last verified
- Oct 2023
- First submitted
- 20 Jun 2023
- Last updated
- 18 Oct 2023
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Publications
Jantarabenjakul W, Nantanee R, Puthanakit T, Gatechompol S, Avihingsanon A, Punrin S, Tantawichien T, Nitayaphan S, Thitithanyanont A, Buranapraditkun S, Jongkaewwattana A, Ketloy C, Prompetchara E, Lawpoolsri S, Wijagkanalan W, Alameh MG, Hong L, Samija M, Weissman D, Ruxrungtham K; ChulaVac006 Study Team. Immunogenicity and safety of 'Comvigen', a bivalent SARS-CoV-2 vaccine, in comparison to Comirnaty bivalent vaccine in Thailand: a phase 2, non-inferiority randomised trial. Lancet Reg Health Southeast Asia. 2025 Aug 15;40:100650. doi: 10.1016/j.lansea.2025.100650. eCollection 2025 Sep.
PubMed 40895389
Study at a glance
From the registry record, last updated by the sponsor on 18 Oct 2023. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 2, Non-inferiority, Open-label, Randomized Controlled Study to Evaluate the Immunogenicity and Safety of Comvigen (Bivalent) Vaccine as a Booster Dose in Adults Who Have Received a Previous Booster Dose of an Approved COVID-19 Vaccine
- ClinicalTrials.gov ID
- NCT05930730
- Acronym / sponsor ID
- ChulaVac 006
- Conditions
- Safety of a Single Dose of COMVIGEN Vaccine, Reactogenicity of a Single Dose of COMVIGEN Vaccine, Immunogenicity of a Single Dose of COMVIGEN Vaccine, Safety of a Single Dose of BIVALENT Pfizer/BNT Vaccine, Reactogenicity of a Single Dose of BIVALENT Pfizer/BNT Vaccine, Immunogenicity of a Single Dose of BIVALENT Pfizer/BNT Vaccine
- Keywords
- Non-inferiority study, Open-label, Randomized Controlled Study, Immunogenicity of the booster dose, safety of booster dose, reactogenicity of booster dose, COMVIGEN (Bivalent, ChulaCov19 BNA159.2 vaccine), Pfizer bivalent vaccine (Comirnaty, BIVALENT)
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Unknown status
- Enrolment
- 450 participants (estimated)
- Lead sponsor
- Chulalongkorn UniversityUniversity, hospital or other
- Collaborators
- Thai Red Cross AIDS Research Centre
- Study start
- 9 Oct 2023 (actual)
- Primary completion
- Feb 2024 (estimated)
- Study completion
- Feb 2024 (estimated)
- First posted
- 5 Jul 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will assess the safety, reactogenicity and immunogenicity of a single dose of Comvigen (Bivalent, ChulaCov19 BNA159.2) vaccine or BIVALENT Pfizer/BNT vaccine as a booster among healthy males and non-pregnant females aged 18-64 years after receiving a previous booster dose of any approved mRNA COVID-19 vaccine for more than 3 months. The results of Combiven will be compared to BIVALENT Pfizer/BNT vaccine.
Detailed description
This is a phase II, non-inferiority, multicenter randomized open-label trial in which 450 healthy males and non-pregnant females, aged 18-64 years, will be recruited from multi-sites in Thailand. The randomization will be a 2:1 design to receive either Comvigen (Bivalent, ChulaCov19 BNA159.2) vaccine or BIVALENT Pfizer/BNT vaccine. This clinical trial is designed to assess the safety, reactogenicity and immunogenicity of a single dose of COMVIGEN at 50 ug, as a booster dose, given at 3 months and above after receipt of a previous booster dose of any approved mRNA COVID-19 vaccine. The estimated sample size would also allow a comparison between a booster dose, Comvigen (Bivalent, ChulaCov19 BNA159.2) vaccine at 50 ug to Comirnaty, BIVALENT of Pfizer/BNT Bivalent vaccine at 30 ug dose.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Comvigen (Bivalent, ChulaCov19 BNA159.2) | Experimental | Biological: Comvigen (Bivalent, ChulaCov19 BNA159.2) |
| BIVALENT Pfizer/BNT vaccine | Active comparator | Biological: BIVALENT Pfizer/BNT vaccine |
Who may qualify
- Ages
- 18 to 64 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (13 listed)
- Participants who meet all the following criteria at Screening are eligible to participate in the study:
- Must be a male or female aged 18 - 64 (inclusive) at the time of enrolment
- Must have completed at least a primary course of 2 doses of any approved COVID-19 vaccine which the last dose have to be mRNA vaccine and completed the last doser 3 months or more
- Must be able to communicate effectively with study personnel and considered reliable, willing, and cooperative in terms of compliance with the protocol requirements
- Participants must sign the written informed consent form prior to undertaking any protocol-related procedures
Key exclusion criteria (13 listed)
- Participants who meet any of the following criteria are not eligible to participate in the study:
- History of a systemic hypersensitivity or life-threatening reaction to a vaccine containing any of the same or similar substances.
- History of test-confirmed by PCR or rapid antigen test to SARS-CoV-2 COVID-19 infection within 3 months prior to randomisation.
- Presence of clinically significant medical history*, unstable chronic or acute disease that, in the opinion of the PI, may increase the risk of exposure to the investigational vaccine
- History of having any significant side effects after receipt of any other COVID-19 vaccine eg. endocarditis, pericarditis or myocarditis. History of any severe reactogenic side effects or other medical illness that were thought to be associated with vaccine.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Comvigen (Bivalent, ChulaCov19 BNA159.2)single dose of COMVIGEN at 50 ug, as a booster dose, given at 3 months and above after receipt of a previous booster dose of any approved mRNA COVID-19 vaccine | Biological | Comvigen (Bivalent, ChulaCov19 BNA159.2) |
| BIVALENT Pfizer/BNT vaccinesingle dose of BIVALENT of Pfizer/BNT Bivalent vaccine at 30 ug, as a booster dose, given at 3 months and above after receipt of a previous booster dose of any approved mRNA COVID-19 vaccine | Biological | BIVALENT Pfizer/BNT vaccine |
Primary outcome
adverse events
Time frame: 30 minutes after vaccination
Presence of immediate adverse events within 30 minutes after vaccination
solicited injection site or systemic reactions
Time frame: within 7 days after vaccination
Presence of solicited injection site or systemic reactions within 7 days after vaccination
unsolicited adverse events
Time frame: within 28 days after vaccination
Presence of unsolicited adverse events within 28 days after vaccination
serious adverse events (SAEs)
Time frame: 169 days
Presence of serious adverse events (SAEs) from day 1 to Day 169
medically attended adverse events (MAAEs)
Time frame: 169 days
Presence of medically attended adverse events (MAAEs) from day 1 to Day 169
New Onset Chronic Medical Condition (NOCMCs)
Time frame: 169 days
Presence of New Onset Chronic Medical Condition (NOCMCs) from day 1 to Day 169
vital signs
Time frame: 169 days
Number of participants with abnormal vital signs
vital signs
Time frame: 169 days
Percent of participants with abnormal vital signs
clinical changes
Time frame: 169 days
Number of participants with abnormal physical examinations finding
clinical changes
Time frame: 169 days
Percent of participants with abnormal physical examinations findingexaminations
Geometric mean titers of neutralizing antibody titer
Time frame: Day 29
Geometric mean titers of neutralizing antibody titer measured by pseudoviral neutralization assay (psVNT-50) against Omicron BA.4/BA.5 exposed to COMVIGEN (Bivalent) vaccine
Geometric mean titers of neutralizing antibody titer
Time frame: Day 29
Geometric mean titers of neutralizing antibody titer measured by pseudoviral neutralization assay (psVNT-50) against wild-type virus exposed to COMVIGEN (Bivalent) vaccine
Geometric mean titers of neutralizing antibody titer
Time frame: Day 29
Geometric mean titers of neutralizing antibody titer measured by pseudoviral neutralization assay (psVNT-50) against Omicron BA.4/BA.5 exposed to BIVALENT vaccine
Geometric mean titers of neutralizing antibody titer
Time frame: Day 29
Geometric mean titers of neutralizing antibody titer measured by pseudoviral neutralization assay (psVNT-50) against wild-type virus exposed to BIVALENT vaccine
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer against wild-type virus exposed to COMVIGEN (Bivalent) vaccine
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer against Omicron BA.4/BA.5 exposed to COMVIGEN (Bivalent) vaccine
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer against wild-type virus exposed to BIVALENT vaccine
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer against Omicron BA.4/BA.5 exposed to BIVALENT vaccine
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer
Time frame: Day 29
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer, psVNT-50 against wild-type virus exposed to COMVIGEN (Bivalent)
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer
Time frame: Day 29
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer, psVNT-50 against Omicron BA.4/BA.5 exposed to COMVIGEN (Bivalent)
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer
Time frame: Day 29
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer, psVNT-50 against against wild-type virus exposed to BIVALENT vaccine
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer
Time frame: Day 29
Proportion of participants with at least 4-fold-rise in neutralizing antibody titer, psVNT-50 against against Omicron BA.4/BA.5 exposed to BIVALENT vaccine
23 secondary outcomes
Geometric mean titers of neutralizing antibody titer
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of psVNT-50 neutralizing antibody titer
Time frame: Day 29
Proportion of participants with at least 4-fold-rise in neutralization antibody titer
Time frame: Day 29
Geometric mean titers of neutralizing antibody titer
Time frame: Day 1
Geometric mean titers of neutralizing antibody titer
Time frame: Day 29
Geometric mean titers of neutralizing antibody titer
Time frame: Day 1
Geometric mean titers of neutralizing antibody titer
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of micro-VNT-50
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of micro-VNT-50
Time frame: Day 29
Proportion of participants with at least 4-fold-rise in micro-VNT-50
Time frame: Day 29
Proportion of participants with at least 4-fold-rise in micro-VNT-50
Time frame: Day 29
Geometric mean titers of anti-RBD antibody titer
Time frame: Day 29
Geometric mean titers of anti-Spike (S) antibody titer
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of anti-RBD antibody
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of anti-S antibody titer
Time frame: Day 29
Proportion of participants with at least 4-fold-rise in anti-RBD
Time frame: Day 29
Proportion of participants with at least 4-fold-rise in anti-RBD
Time frame: Day 29
Geometric mean of SARS-CoV2-specific T-cell responses
Time frame: Day 1
Geometric mean of SARS-CoV2-specific T-cell responses
Time frame: Day 29
median number of SARS-CoV2-specific T-cell responses
Time frame: Day 1
median number of SARS-CoV2-specific T-cell responses
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of SARS-CoV2-specific T-cell responses
Time frame: Day 29
Geometric mean of the fold-rise post-vaccination of SARS-CoV2-specific T-cell responses
Time frame: Day 29
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Oct 2023.
- Derived from this study: PubMed 40895389Jantarabenjakul W, Nantanee R, Puthanakit T, Gatechompol S, Avihingsanon A, Punrin S, Tantawichien T, Nitayaphan S, Thitithanyanont A, Buranapraditkun S, Jongkaewwattana A, Ketloy C, Prompetchara E, Lawpoolsri S, Wijagkanalan W, Alameh MG, Hong L, Samija M, Weissman D, Ruxrungtham K; ChulaVac006 Study Team. Immunogenicity and safety of 'Comvigen', a bivalent SARS-CoV-2 vaccine, in comparison to Comirnaty bivalent vaccine in Thailand: a phase 2, non-inferiority randomised trial. Lancet Reg Health Southeast Asia. 2025 Aug 15;40:100650. doi: 10.1016/j.lansea.2025.100650. eCollection 2025 Sep.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Watsamon Jantarabenjakul, MD principal investigator
Department of Pediatric, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
Sivaporn Gatechompol, MD principal investigator
HIVNAT, Thai Red Cross AIDS Research Centre, Bangkok, Thailand
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Comvigen (Bivalent, ChulaCov19 BNA159.2) and BIVALENT Pfizer/BNT vaccine in people with Safety of a Single Dose of COMVIGEN Vaccine and Reactogenicity of a Single Dose of COMVIGEN Vaccine, run by Chulalongkorn University at 2 sites in Thailand.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 13 inclusion and 13 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: status not confirmed, as of the sponsor's last update on 18 Oct 2023. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Thailand. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
Contact Watsamon Jantarabenjakul, MD (+66 818276255, watsamon.j@chula.ac.th), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
adverse events (time frame: 30 minutes after vaccination). The study lists 22 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05930730, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Oct 2023.