ChulaCov19 Vaccine in Healthy Adults

A Phase 1/2, Dose-finding Study to Evaluate Safety, Tolerability, and Immunogenicity of the ChulaCov19 Vaccine in Healthy Adults

Status

Completed

Phases

Phase 1Phase 2

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT04566276

Enrollment

192

Registered

2020-09-28

Start date

2021-05-03

Completion date

2022-12-06

Last updated

2023-02-09

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

Conditions

COVID-19 Vaccine, Safety Issues

Keywords

tolerability, reactivity, immunogenicity, healthy adults, healthy elderlies, coronavirus disease 2019, SARS-CoV-2-specific serum neutralising antibody titer, SARS-CoV-2-surrogate viral neutralising antibody, SARS-Cov2 spike protein-binding IgG antibody titer, SARS-Cov2 spike protein-specific CD4+ and CD8+ T-cells responses, IFNγ enzyme-linked immune absorbent spot (ELISpot), SARS-Cov2 spike protein-specific Th1/Th2 polarisation, novel lipid nanoparticles (LNPs)-encapsulated mRNA-based vaccine

Brief summary

This study will be conducted in 2 phases. Phase 1 of this study will be a single-centre, open label, dose escalation first in human (FIH) study conducted in 2 groups of healthy participants. Group 1 will enrol adults aged 18-55 years (inclusive); Group 2 will enroll elderly adults (elderly) aged 56-75 years (inclusive). Phase 2 of this study will be a single centre, the proposed design will be observer-blind, placebo-controlled study to assess the safety, reactogenicity, and immunogenicity of ChulaCov19 vaccine in healthy adults (18-75 years of age inclusive).

Detailed description

This study will be conducted as a combined phase 1/2 study in healthy participants. The first phase of the study will evaluate the safety, tolerability, and reactogenicity of escalating doses (10 µg, 25 µg, and 50 µg) of the ChulaCov19 vaccine, administered intramuscularly (IM) according to a repeat vaccination schedule (given 21 days apart) in healthy adults aged 18-55 years and in elderly adults aged 56-75 years, up to Visit 10 (Day 50 ±3). The second phase of the study will evaluate the safety, tolerability, and reactogenicity of escalating doses of the ChulaCov19 vaccine, administered intramuscularly (IM) according to a repeat vaccination schedule (given 21 days apart) in healthy adults aged 18--75 years, up to Visit 10 (Day 50 ±3). The study will also evaluate the immunogenicity measured as neutralising antibody titre (measured by Micro-viral neutralising test \[MicroVNT\]) following repeat vaccination of escalating doses of the ChulaCov19 vaccine, administered IM according to a repeat vaccination schedule (given 21 days apart) in healthy adults aged 18-75 years, at Visit 9 (Day 29 +3).

Interventions

BIOLOGICALChulaCov19 vaccine

SARS-Cov2 Wild-type S-spike mRNA/ lipid nanoparticle (LNP) vaccine

OTHERPlacebo

Saline

Study design

Allocation

RANDOMIZED

Intervention model

SEQUENTIAL

Primary purpose

OTHER

Masking

TRIPLE (Subject, Investigator, Outcomes Assessor)

Intervention model description

Phase 1: Group 1 (healthy adults aged 18 to 55 years) and Group 2 (elderlies aged 56 to 75 years) will be enrolled sequentially in an ascending dose fashion (10 µg, 25 µg, 50 µg). Up to 36 eligible healthy volunteers for each of the 2 age groups will be enrolled into 1 of 3 treatment cohorts (12 participants/ cohort). For each cohort, if only 1 participant withdraws prior to the second vaccination, no replacement is deemed necessary. For each cohort, if more than 1 participant withdraws prior to the second vaccination all withdrawn participants will be replaced. Phase 2: The Phase 2 adult cohorts will include adults between 18 and 59 years of age (inclusive). Participants in the Phase 2 will be enrolled into at least 1 dose level cohort with a vaccination dose of 50 ug which was determined by DSMB and SRPT review and approval of the applicable Phase 1 data. Phase 2 treatment group will consist of participants randomly assigned to active treatment versus placebo in a ratio of 4:1.

Eligibility

Sex/Gender

ALL

Age

18 Years to 75 Years

Healthy volunteers

Yes

Inclusion criteria

Participants who meet all the following criteria at Screening are eligible to participate in the study: Inclusion criteria: 1. Participants must be able to communicate effectively with study personnel and considered reliable, willing, and cooperative in terms of compliance with the protocol requirements. 2. Participants must sign the written informed consent form prior to undertaking any protocol related procedures. 3. Participants must have a body mass index (BMI) at Screening, calculated as the body mass divided (in kilograms \[kg\]) by the square of the body height (in metres \[m\]) of 18.0-30.0 kg/m2, inclusive. 4. Participants must have haematology, clinical chemistry, coagulation (for all participants in Phase 1, and, only if applicable, for participants in Phase 2), and urinalysis test results that are not deviating from the normal reference range by age and gender to a clinically relevant extent at Screening. 5. 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 the last dose of investigational vaccine. 6. Women of child-bearing potential must practice true abstinence or, if engaged in sexual relations with a male, they must agree to use highly effective (failure rate of \< 1% per year when used consistently and correctly), double-barrier contraceptive measures\* throughout the study and intend to continue use of contraception for at least 60 days following the last vaccination. \* The PI is to assess the adequacy of methods of contraception on a case-by-case basis. These criteria do not apply if the participants are in a same-sex relationship. 7. Women of child-bearing potential must have a negative serum pregnancy test (beta human chorionic gonadotropin \[β-HCG\]) at Screening and a negative urine-based test within 24 hours prior to each investigational vaccine administration. 8. Women of non-child-bearing potential must: 1. be classified as being postmenopausal (defined as having a history of amenorrhea of at least one year), or 2. where history of amenorrhea is less than one year, female participants must have a follicle stimulating hormone (FSH) level \> 40 milli-international units per milliliter (mIU/mL), or 3. have a documented status of being surgically sterile (hysterectomy, bilateral oophorectomy, or tubal ligation/salpingectomy). 9. Participants must be in general good health based on medical history and physical examination, as determined by the PI, at Screening. 10. Body temperature must be less than 37.8ºC, at Screening. 11. Pulse must be no greater than 100 beats per minute, at Screening. 12. Systolic blood pressure (SBP) must be between 85 to 150 millimetres of mercury (mm Hg), inclusive, at Screening. 13. Participants must agree to refrain from donating blood, plasma, ovules, sperm, or organs during the whole study. Adult Participants (Group 1 of Phase 1) only 14. Must be a male or female aged 18-55 years (inclusive) at the time of enrolment. Elderly Participants (Group 2 of Phase 1) only 15. Must be a male or female aged 56-75 years (inclusive) at the time of enrolment. Participants for Phase 2 only 16. Must be a male or female aged 18 -59 years (inclusive) at the time of enrolment.

Exclusion criteria

The presence of any of the following criteria will constitute cause for the exclusion of the participant: 1. Presence of clinically significant medical history, unstable chronic or acute disease, or physical, or laboratory findings that, in the opinion of the PI may potentially increase the expected risk of exposure to the investigational vaccine, compromise the safety of the participant, or interfere with any aspect of study conduct or interpretation of results. This will include asthma and any thrombocytopenia or bleeding disorder contraindicating IM vaccination. 2. Presence of self-reported or medically documented significant medical or psychiatric condition(s). 3. Presence of an acute illness, as determined by the participating site PI or appropriate sub-PI, with or without fever (temperature ≥ 38.0 ºC) within 72 hours prior to each vaccination. 4. Presence of birthmarks, tattoos, wound, or other skin conditions over the deltoid region of both arms that, in the PI's opinion, could reasonably obscure and interfere with evaluation of local ISRs. 5. Inadequate venous access to allow collection of blood samples. 6. Breastfeeding or planning to breastfeed from the time of the first vaccination through 60 days after the last vaccination, or pregnant as confirmed by a positive serum β-HCG pregnancy test at Screening or positive urine pregnancy test at subsequent clinic visits at timepoints as delineated in the schedule of assessments. 7. Received any prophylactic or therapeutic vaccine, or licensed or unlicensed vaccine, drug, biologic, device, blood product, or medication, within 4 weeks of first vaccination or 5 half-lives (whichever is longer), or anticipate to do so in the follow-up period defined for this study. 8. Participant has previously participated in an investigational study involving LNPs (a component of the investigational vaccine assessed in this trial). 9. History of severe allergy (requiring hospital care), severe reaction to any drug or prior vaccination, or any known or suspected allergies or sensitivities to any component of the investigational vaccine or placebo. 10. History of ever had an anaphylaxis reaction to food, medication or vaccination. 11. Participant is immunosuppressed as caused by disease (such as HIV). 12. Chronic use (more than 14 continuous days) of or anticipated need to use, within the next 6 months, of any medications that may be associated with impaired immune responsiveness or with immunosuppression. 13. History of hepatitis B or hepatitis C infection. 14. Receipt of immunoglobulins or blood products within 3 months of first vaccination. 15. Requirement for antipyretic or analgesic medication on a daily or every other day basis from enrolment through 72 hours after vaccination. 16. Current use of any prescription or over-the-counter medications within 7 days prior to vaccination, unless approved by the PI. 17. History of alcohol or drug abuse that in the opinion of the PI could affect the participant's safety or compliance with study. 18. Participant unwilling to abstain from blood donation during the course of the study, and/or participation in any research study involving blood sampling (more than 450 mL /unit of blood), or blood donation to any blood bank during the 2 months prior to the Screening visit. 19. Close contact with anyone known to have SARS-CoV-2 infection within 30 days prior to vaccine administration. 20. Positive for SAR-CoV-2 by antibody IgG/IgM and anti spike IgG at screening 21. History of COVID-19 diagnosis (the criteria for COVID-19 diagnosis will follow the local guidelines). 22. On current treatment with investigational agents for prophylaxis of COVID-19. 23. Planning to travel outside Thailand from enrolment through 28 days after the second vaccination. 24. Residing in a nursing home or other skilled nursing facility or having a requirement for skilled nursing care. 25. Is a participant at high risk of SARS-CoV2 exposure in the opinion of the PI (e.g., healthcare workers, active health care workers with direct patient contact, emergency response personnel). Elderly Participants (Group 2 of Phase 1) only 26. Chronically smoking (defined as ≥10 Pack years \[packs/day × years smoked\]) within the 12 months prior to enrolment. 27. Presence of co-morbidities that can be associated with an increased risk of severe COVID-19 Cancer, Chronic kidney diseases, COPD, cardiovascular disease, solid organ transplantation, DM type 2, HT, cerebrovascular disease, Obesity (BMI\> 30 kg/m2) Participants for Phase 2 only 28. Presence of co-morbidities that can be associated with an increased risk of severe COVID-19 Cancer, Chronic kidney diseases, COPD, cardiovascular disease, solid organ transplantation, DM type 2, uncontrolled HT, cerebrovascular disease

Design outcomes

Primary

Measure	Time frame	Description
Phase 1 and 2: Frequency of Adverse Events	up to Day 50	Frequency of Adverse Events
Phase 1 and 2: Grade of Adverse Events	up to Day 50	Grade of Adverse Events
Phase 1 and 2: Frequency of solicited reportable local Adverse Events	during a 7-day follow-up period post each vaccination	Frequency of solicited reportable local Adverse Events (i.e., pain, tenderness, erythema/redness, induration/swelling, ulceration, scabs, ecchymosis, oedema, itching, paraesthesia, and hypersensitivity)
Phase 1 and 2: Grade of solicited reportable local Adverse Events	during a 7-day follow-up period post each vaccination	Grade of solicited reportable local Adverse Events: (i.e., pain, tenderness, erythema/redness, induration/swelling, ulceration, scabs, ecchymosis, oedema, itching, paraesthesia, and hypersensitivity)
Phase 1 and 2: Frequency of solicited reportable systemic reactogenicity Adverse Events	during a 7-day follow-up period post each vaccination	Frequency of solicited reportable systemic Adverse Events: (i.e., headache, fatigue, myalgia, malaise, fever, rigors, arthralgia, nausea/vomiting, diarrhea, light headedness, dizziness, or any other symptoms)
Phase 1 and 2: Grade of of solicited reportable systemic Adverse Events	during a 7-day follow-up period post each vaccination	Grade of solicited reportable systemic Adverse Events: (i.e., headache, fatigue, myalgia, malaise, fever, rigors, arthralgia, nausea/vomiting, diarrhea, light headedness, dizziness, or any other symptoms)
Phase 1 and 2: Frequency of Serious Adverse Events	up to Day 387	Frequency of Serious Adverse Events
Phase 1 and 2: Frequency of Medically-Attended Adverse Events	up to Day 387	Frequency of Medically-Attended Adverse Events
Phase 1 and 2: Frequency of New-Onset Chronic Medical Conditions	up to Day 387	Frequency of New-Onset Chronic Medical Conditions
Phase 1 and 2: Changes in vital signs	up to Day 50	Changes in vital signs: (i.e., body temperature, respiratory rate, pulse rate, systolic blood pressure (SBP), and diastolic blood pressure (DBP))
Phase 1 and 2: Changes in physical examinations	up to Day 50	Changes in physical examinations: (i.e., head, ears, nose, throat, lungs, lymph nodes, heart, abdomen and skin)
Phase 1 and 2: Changes in laboratory measurements	up to Day 50	Changes in laboratory measurements: (i.e., haemoglobin (Hb), haematocrit (HCT), white blood cells (WBC), neutrophil, lymphocytes, eosinophil, basophil, monocytes, platelet, sodium, potassium, chloride, bicarbonate, blood urea nitrogen (BUN), creatinine, total protein, albumin, lipase, phosphorus, gamma-glutamyl transferase (GGT), glucose, creatinine phosphokinase (CPK), calcium, uric acid, C-reactive protein (CRP), alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), total bilirubin, estimated glomerular filtration rate (eGFR), prothrombin time (PR), partial thromboplastin time (PTT) and international normalized ratio (INR))
Phase 1 and 2: Presence of injection site reactions	up to Day 50	Presence of injection site reactions
Phase 2: Geometric mean titers (GMT) in SARS-CoV-2-specific serum neutralising antibody levels	at Day 29 (7 days after the second dose)	Geometric mean titers (GMT) in SARS-CoV-2-specific serum neutralising antibody levels

Secondary

Countries

Thailand

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 12, 2026

Measure	Time frame	Description
Phase 1 and Phase 2: Median percentage specific Th1 responses	Day 29	Median percentage specific Th1 responses
Phase 1: Geometric mean titers (GMT) in SARS-CoV-2-specific serum neutralising antibody levels	at Day 29 (7 days after the second dose)	Geometric mean titers (GMT) in SARS-CoV-2-specific serum neutralising antibody levels
Phase 1 and Phase 2: Median percentage specific Th2 responses	Day 29	Median percentage specific Th2 responses
Phase 1 and Phase 2: Proportion of participants who achieved a greater than or equal to 4-fold rise from before vaccination in SARS-CoV-2-specific serum neutralising antibody levels	At Day 29	Proportion of participants who achieved a greater than or equal to 4-fold rise from before vaccination in SARS-CoV-2-specific serum neutralising antibody levels
Phase 1 and Phase 2: Geometric mean fold rises (GMFR) in SARS-CoV-2-specific serum neutralising titers	from baseline to Day 29	Geometric mean fold rises (GMFR) in SARS-CoV-2-specific serum neutralising titers
Phase 1 and Phase 2: Geometric mean titers (GMT) in SARS-CoV-2 surrogate viral neutralising antibody levels	at Day 29	Geometric mean titers (GMT) in SARS-CoV-2 surrogate viral neutralising antibody levels
Phase 1 and Phase 2: Proportion of participants who achieved a greater than or equal to 4-fold rise from before vaccination in SARS-CoV-2 surrogate viral neutralising antibody levels	at Day 29	Proportion of participants who achieved a greater than or equal to 4-fold rise from before vaccination in SARS-CoV-2 surrogate viral neutralising antibody levels
Phase 1 and Phase 2: Geometric mean fold rises (GMFR) in SARS-CoV-2 surrogate viral neutralising antibody titers	from baseline to Day 29	Geometric mean fold rises (GMFR) in SARS-CoV-2 surrogate viral neutralising antibody titers
Phase 1 and Phase 2: Geometric mean titers (GMT) of SARS-Cov2-spike protein-binding IgG antibody	at Day 29	Geometric mean titers (GMT) of SARS-Cov2-spike protein-binding IgG antibody
Phase 1 and Phase 2: Proportion of participants who seroconverted: achieving a greater than or equal to 4-fold rise in SARS-Cov2-spike protein-binding IgG antibody	from baseline to Day 29	Proportion of participants who seroconverted: achieving a greater than or equal to 4-fold rise in SARS-Cov2-spike protein-binding IgG antibody
Phase 1 and Phase 2: Geometric mean fold rises (GMFR) in SARS-Cov2-spike protein-binding IgG antibody	from baseline to Day 29	Geometric mean fold rises (GMFR) in SARS-Cov2-spike protein-binding IgG antibody
Phase 1 and Phase 2: Percentage of participants who have positive specific CD4 T-cell IFNγ ELISpot responses	Day 29	Percentage of participants who have positive specific CD4 T-cell IFNγ ELISpot responses
Phase 1 and Phase 2: Percentage of participants who have positive specific CD8 T-cell IFNγ ELISpot responses	Day 29	Percentage of participants who have positive specific CD8 T-cell IFNγ ELISpot responses
Phase 1 and Phase 2: Median number of spot-forming cells (SFC) per 1 million PBMCs	Day 29	Median number of spot-forming cells (SFC) per 1 million PBMCs
Phase 1 and Phase 2: Percentage of participants who shows positive specific Th1 responses	Day 29	Percentage of participants who shows positive specific Th1 responses
Phase 1 and Phase 2: Percentage of participants who shows positive specific Th2 responses	Day 29	Percentage of participants who shows positive specific Th2 responses