CompletedNCT05144139Updated Dec 28, 2022

A Phase I/II Clinical Trial in Healthy People Aged 18 Years and Above

A Phase 1/2 interventional study of COVID-19 mRNA vaccine in COVID-19 Pandemic, sponsored by Stemirna Therapeutics. Completed at 1 site in Lao People's Democratic Republic. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2022-12-28.

Sponsored by Stemirna Therapeutics · Phase 1/2, Interventional, and Prevention

Phase: Phase 1/2
Study type: Interventional
Enrollment: 480
Allocation: Randomized
Ages: 18 Years and older
Sex: All

Study summary

This clinical trial is a phase I/II clinical trial to evaluate the safety, immunogenicity and immune persistence of COVID-19 mRNA vaccine in healthy people aged 18 years and above.

Read the detailed description

This is the clinical trial including an open-label, single-arm Phase I study and a subsequent randomized, blind, placebo-parallel controlled Phase II study to evaluate the safety, immunogenicity and immune persistence of COVID-19 mRNA vaccine in healthy people aged 18-60 years and ≥18 years respectively, whose locations or circumstances put them at appreciable risk of acquiring COVID-19 and/or SARS-CoV-2 infection.

Conditions studied

COVID-19 Pandemic

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COVID-19 7,640

In context

COVID-19

7,640 studies on the registry are indexed under COVID-19; 488 are open to participants now.

This study's enrollment of 480 is above the median of 100 across 4,099 interventional studies indexed under COVID-19.

Browse COVID-19 studies →

Lead sponsor

Stemirna Therapeutics is the lead sponsor of 7 studies on the registry; 3 are open to participants now.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: All
Accepts healthy volunteers: Yes

Inclusion criteria

People aged 18-60 years (both inclusive) for phase 1 and aged ≥18 years for phase 2；
Medical history and physical examination indicating as a healthy person;
The female participant or the spouse (or partner) of the male participant in child-birthing age agrees to use effective contraceptive measure throughout the whole course of this clinical trial.
Those who are participating in this clinical trial voluntarily, have signed the informed consent form, and been able to understand and comply with the requirements of the clinical trial protocol.

Exclusion criteria

Exclusion Criteria:

Confirmed cases or history of SARS-CoV-2 infection;
Has a history of SARS and MERS virus infection;
Has fever (axillary temperature ≥37.3℃), dry cough, fatigue, nasal congestion, runny nose, sore throat, myalgia, diarrhea, shortness of breath, and dyspnea within 14 days before vaccination;
Positive urine pregnancy test；
Axillary temperature ≥37.3℃ at the day vaccinated;
History of severe allergic reactions to vaccination (such as acute allergic reactions, urticaria, dyspnea, angioneurosis, edema, etc.) or allergies to known components of COVID-19 mRNA vaccine;
History or family history of convulsions, epilepsy, encephalopathy, or mental illness;
Suffering from congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.;
Known suffering from diseases including: acute respiratory disease (such as flu-like illness, acute cough, sore throat), severe cardiovascular disease, kidney disease, uncontrolled hypertension (systolic blood pressure >150 mmHg, diastolic blood pressure >90 mmHg), diabetes complications, malignant tumor, all sorts of acute illness or chronic diseases acute phase;
Diagnosis with congenital or acquired immunodeficiency, HIV infection, lymphoma, leukemia, or other autoimmune disease;
Abnormal coagulation function (such as lack of coagulation factor, coagulation disorders);
Receiving anti-tuberculosis treatment;
Long-term receipt (continuous≥7 days) of glucocorticoid (reverence value for dose: amount to≥20 mg/d prednisone equivalent), except inhaled, topical, nasal, aural and ophthalmic corticosteroids, within 6 months before screening; Receipt of immunotherapy or immunosuppressant within 3 months (continuous oral or infusion for more than 14 days);
Receipt of live attenuated vaccine within 28 days prior to vaccination and other vaccines within 14 days prior to vaccination;
Receipt of blood products within 3 months prior to vaccination
Receipt of other study drugs within 6 months prior to vaccination;
Receipt of any SARS-COV-2 vaccine;
Other situations judged by the investigators that are not suitable for participating in this clinical trial.

Study design

Phase: Phase 1 / Phase 2
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Sequential assignment
Masking: Double (Participant, Investigator)
Enrollment: 480 participants (actual)

Study arms

Experimental
Low dose group with mRNA vaccine
25μg with COVID-19 mRNA vaccine
Biological: COVID-19 mRNA vaccine
Placebo comparator
Low dose group with placebo
Low dose group with placebo
Biological: COVID-19 mRNA vaccine
Experimental
High dose group with mRNA vaccine
45μg with COVID-19 mRNA vaccine
Biological: COVID-19 mRNA vaccine
Placebo comparator
High dose group with placebo
High dose group with placebo
Biological: COVID-19 mRNA vaccine

Interventions

BiologicalCOVID-19 mRNA vaccine
Intramuscular injection, COVID-19 mRNA vaccine/placebo, 21 days interval

What researchers measure

Primary outcomes

local/systemic solicited adverse reaction/events
The incidence of local/systemic solicited adverse reaction/events
Time frame: up to 6 days after each dose
unsolicited adverse events
The incidence of unsolicited adverse events
Time frame: up to 21 days and up to 28 days after the first and second dose of immunization, respectively
The incidence of SAE
The incidence of SAE from the first dose of vaccination to 28 days after the full course of immunization
Time frame: up to 28 days after the full course of immunization

Secondary outcomes

The seroconversion rate, 2-fold or 4-fold rise and GMT/GMI of the SARS-COV-2 S-protein specific antibody (specific total antibody/IgG antibody) and neutralizing antibody
The seroconversion rate, 2-fold or 4-fold rise and GMT/GMI of the SARS-COV-2 S-protein specific antibody (specific total antibody/IgG antibody) and neutralizing antibody 14 days after the full immunization in the subjects who take two doses as protocol specified
Time frame: 14 days after the full immunization
The incidence of SAE
The incidence of SAE within the 29th \~365th day after the full course of immunization
Time frame: the 29th ~365th day after the full course of immunization
Changes in laboratory abnormal parameters
Changes in laboratory abnormal parameters in the participants who take at least of one dose
Time frame: after at least of one dose

Other outcomes

The positive conversion rate, 2-fold or 4-fold rise and GMT/GMI of the SARS-COV-2 S-protein specific antibody (specific total antibody/IgG antibody), neutralizing antibody
The positive conversion rate, 2-fold or 4-fold rise and GMT/GMI of the SARS-COV-2 S-protein specific antibody (specific total antibody/IgG antibody), neutralizing antibody before 1st and 2nd immunization, 90, 180, 365 days after the full immunization
Time frame: before 1st and 2nd immunization, 90, 180, 365 days after the full immunization
Cellular immunity INF-γ, IL-4 and IL-2
Cellular immunity (INF-γ, IL-4 and IL-2) before 1st and 2nd immunization, and 14, 90, 180, 365 days after the full immunization
Time frame: before 1st and 2nd immunization, and 14, 90, 180, 365 days after the full immunization

Study locations

1 site

Mayfong Mayxay
Vientiane, 01000, Lao People's Democratic Republic

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Dec 28, 2022, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT05144139
Lead sponsor: Stemirna Therapeutics
Responsible party: Sponsor
First posted: Dec 3, 2021
Start date: Dec 3, 2021
Primary completion: Aug 28, 2022
Completion: Nov 11, 2022
Last update: Dec 28, 2022

Study contacts

Mayfong Mayxay, professor

principal investigator · Mahosot Hospital

Oversight

Data monitoring committee: Yes
FDA-regulated drug: No
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Oct 2022. You cannot join it, but the record below documents what was studied.

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