SARS-CoV-2 Infection
Conditions
Brief summary
The objective of this study is to evaluate the safety and immunogenicity of MT-2766 in Japanese adults.
Interventions
DRUGPlacebo
Subjects will receive two doses of placebo given 21 days apart into the deltoid region of the alternating arm (each arm will be injected once)
BIOLOGICALMT-2766 Low dose
Subjects will receive two doses of MT-2766 low dose given 21 days apart into the deltoid region of the alternating arm (each arm will be injected once)
BIOLOGICALMT-2766 High dose (3.75 µg)
Subjects will receive two doses of MT-2766 high dose (3.75 µg) given 21 days apart into the deltoid region of the alternating arm (each arm will be injected once)
Sponsors
Tanabe Pharma Corporation
Medicago
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Masking description
MT-2766 High dose group and placebo group are randomized and observer-blinded. MT-2766 Low dose group is open label.
Eligibility
Sex/Gender
ALL
Age
20 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
\- Subjects must meet all of the following inclusion criteria at the Screening visit (Visit 1) and/or 1st vaccination visit (Visit 2) to be eligible for participation in this study. All Investigator assessment-based judgments must be carefully and fully documented in the source documents: 1. Subjects must have read, understood, and signed the informed consent form (ICF) prior to participating in the study; subjects must also complete study-related procedures and must communicate with the study staff at visits and by phone during the study; 2. At the Screening visit (Visit 1), Japanese male and female subjects must be ≥20 years of age; 3. At the Screening visit (Visit 1) and 1st vaccination visit (Visit 2), subject must have a body mass index (BMI) of ≥18.5 kg/m\^2 and \<30 kg/m\^2; 4. Subjects are considered by the Investigator to be reliable and likely to cooperate with the assessment procedures and be available for the duration of the study; 5. Female subjects of childbearing potential must have a negative serum pregnancy test result at the Screening visit (Visit 1) and a negative urine pregnancy test result at 1st vaccination visit (Visit 2): Non-childbearing females are defined as: * Surgically sterile (defined as bilateral tubal ligation, hysterectomy or bilateral oophorectomy performed more than one month prior to the first study vaccination); OR * Post-menopausal (absence of menses for 12 consecutive months and age consistent with natural cessation of ovulation); 6. Female subjects of childbearing potential must use an effective method of contraception for one month prior to 1st vaccination visit (Visit 2) and agree to continue employing highly effective birth control measures for at least one month after the last study vaccination (or in the case of early termination, she must not plan to become pregnant for at least one month after her last study vaccination); 7. Subjects must be non-institutionalized (e.g. not living in rehabilitation centers or old-age homes); 8. Subjects have no acute or evolving medical problems prior to study participation and no clinically relevant abnormalities that could jeopardize subject safety or interfere with study assessments, as assessed by the Principal Investigator or sub-Investigator (thereafter referred as Investigator) and determined by medical history, physical examination, serology, clinical chemistry and hematology tests, urinalysis, and vital signs. Investigator discretion is permitted with this inclusion criterion.
Exclusion criteria
* Subjects who meet any of the following
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses | Day 0 (before 1st vaccination), Day 21 (21 days after 1st vaccination and before 2nd vaccination), and Day 42 (21 days after 2nd vaccination) | Using the interleukin-4 ELISpot assay |
| Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Within 30 minutes after each vaccination | Immediate AEs are defined as any solicited AEs and unsolicited AEs occurring within 30 minutes after vaccination. The causal relationship of all solicited AEs to investigational product was analyzed as related. |
| Percentage of Participants With Solicited AEs According to Severity | Within 7 days after each vaccination | Solicited AEs are defined the following; (i) local AEs (injection site erythema, injection site swelling, injection site induration, and injection site pain) and (ii) systemic AEs (fever, headache, fatigue, muscle aches, joint aches, chills, a feeling of general discomfort, swelling in the axilla, and swelling in the neck)． |
| Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Within 21 days after each vaccination | — |
| Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Within 21 days after each vaccination | AESIs include vaccine-associated enhanced diseases, hypersensitivity reactions, and potential immune-mediated diseases |
| SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | Day 0 (before 1st vaccination), Day 21 (21 days after 1st vaccination and before 2nd vaccination), and Day 42 (21 days after 2nd vaccination) | Geometric mean neutralizing antibody titer (GMT) |
| SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR | Day 21 (21 days after 1st vaccination and before 2nd vaccination), and Day 42 (21 days after 2nd vaccination) | Geometric mean fold rise (GMFR) is defined as the ratio of geometric mean antibody titer (GMT) based on that of Day 0 (i.e. Day 21/Day 0 and Day 42/Day 0). |
| SARS-CoV-2 Neutralizing Antibody (Nab) Responses | Day 0 (before 1st vaccination), Day 21 (21 days after 1st vaccination and before 2nd vaccination), and Day 42 (21 days after 2nd vaccination) | Seroconversion (SC) rate. SC rate is defined as the proportion of subjects achieving SC in the analysis set i.e. subjects with: * For subjects with detectable Nab titer at Day 0 (i.e. baseline Nab titer ≥10): a ≥ 4-fold increase in Nab titers between Day 0 and Day 21/42, respectively. * For subjects with undetectable Nab titer at Day 0 (i.e. baseline Nab titer \< 10): Nab titer of ≥ 40 on Day 21/42, respectively. |
| SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses | Day 0 (before 1st vaccination), Day 21 (21 days after 1st vaccination and before 2nd vaccination), and Day 42 (21 days after 2nd vaccination) | Using the interferon-γ enzyme-linked immunospot (ELISpot) assay. Unit of Measure: Spot-Forming Cell (SFC)/10\^6 Peripheral Blood Mononuclear Cells (PBMC) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Day 0 (after 1st vaccination) to end of study, on average the study duration by the termination is 334 days. | AESIs include vaccine-associated enhanced diseases, hypersensitivity reactions, and potential immune-mediated diseases. |
| SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | Day 128 and Day 201 | Geometric mean neutralizing antibody titer (GMT) |
| SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR | Day 128 and Day 201 | Geometric mean fold rise (GMFR) |
| Seroconversion (SC) Rate of SARS-CoV-2 Neutralizing Antibody | Day 128 and Day 201 | SC rate is defined as the proportion of subjects achieving SC in the analysis set i.e. subjects with: * For subjects with detectable Nab titer at Day 0 (i.e. baseline Nab titer ≥10): a ≥ 4-fold increase in Nab titers between Day 0 and Day 128/201, respectively. * For subjects with undetectable Nab titer at Day 0 (i.e. baseline Nab titer \< 10): Nab titer of ≥ 40 on Day 128/201, respectively. |
| SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses | Days 201 | Using the interferon-γ enzyme-linked immunospot (ELISpot) assay. |
| SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses | Days 201 | Using the interleukin-4 ELISpot assay |
| SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | Day 0，Day 21，Day 42，Day 128 and Day 201 | Geometric mean neutralizing antibody titer (GMT) |
| SARS-CoV-2-specific Antibody Responses (Total IgG): GMFR | Day 0，Day 21，Day 42，Day 128 and Day 201 | Geometric mean fold rise (GMFR) |
| Seroconversion (SC) Rate of SARS-CoV-2-specific Antibody Responses (Total IgG): | Day 0，Day 21，Day 42，Day 128 and Day 201 | SC rate is defined as the proportion of subjects achieving SC in the analysis set i.e. subjects with: * For subjects with detectable Nab titer at Day 0 (i.e. baseline Nab titer ≥10): a ≥ 4-fold increase in Nab titers between Day 0 and Day 21/42/128/201, respectively. * For subjects with undetectable Nab titer at Day 0 (i.e. baseline Nab titer \< 10): Nab titer of ≥ 40 on Day 21/42, respectively. |
Countries
Japan
Participant flow
Pre-assignment details
Low dose arm is open-label, not randomized arm and was not enrolled. It was described in the protocol that the study may be completed even if fewer than planned number of subjects in Low dose arm are enrolled.
Participants by arm
| Arm | Count |
|---|---|
| MT-2766 High Dose (3.75 µg) Subjects received two doses of MT-2766 high dose (3.75 µg) given 21 days apart into the deltoid region of the alternating arm (each arm will be injected once). | 101 |
| Placebo Subjects received two doses of placebo given 21 days apart into the deltoid region of the alternating arm (each arm will be injected once). | 26 |
| Total | 127 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| After Day 43 | Difficult to go to the hospital due to moving | 1 | 0 |
| After Day 43 | Lost to Follow-up | 1 | 0 |
| After Day 43 | Physician Decision | 3 | 0 |
| After Day 43 | Public vaccination | 6 | 8 |
| After Day 43 | Study Terminated by Sponsor | 88 | 16 |
| After Day 43 | Withdrawal by Subject | 1 | 2 |
| Up to Day 42 | Lost to Follow-up | 1 | 0 |
| Up to Day 42 | Withdrawal by Subject | 1 | 0 |
Baseline characteristics
| Characteristic | MT-2766 High Dose (3.75 µg) | Placebo | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 4 Participants | 1 Participants | 5 Participants |
| Age, Categorical Between 18 and 65 years | 97 Participants | 25 Participants | 122 Participants |
| Age, Continuous | 46.7 years STANDARD_DEVIATION 11.3 | 46.8 years STANDARD_DEVIATION 11.9 | 46.7 years STANDARD_DEVIATION 11.4 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants | 0 Participants | 0 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 101 Participants | 26 Participants | 127 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 101 Participants | 26 Participants | 127 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 0 Participants | 0 Participants | 0 Participants |
| Sex: Female, Male Female | 36 Participants | 15 Participants | 51 Participants |
| Sex: Female, Male Male | 65 Participants | 11 Participants | 76 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 101 | 0 / 26 |
| other Total, other adverse events | 92 / 101 | 11 / 26 |
| serious Total, serious adverse events | 2 / 101 | 2 / 26 |
Outcome results
Primary
Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality
Immediate AEs are defined as any solicited AEs and unsolicited AEs occurring within 30 minutes after vaccination. The causal relationship of all solicited AEs to investigational product was analyzed as related.
Time frame: Within 30 minutes after each vaccination
Population: Safety population included all randomized subjects who received at least 1 dose of the investigational product.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Solicited AE: Severe | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Unsolicited AE: Mild | 1.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Solicited AE: Moderate | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Unsolicited AE: Moderate | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Solicited AE: Potentially life-threatening | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Unsolicited AE: Severe | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Solicited AE: Mild | 11.9 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Unsolicited AE: Potentially life-threatening | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Percentage of Participants with Immediate Unsolicited AE | 1.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Percentage of Participants with Immediate Related Unsolicited AE | 1.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Percentage of Participants with Immediate Solicited AEs | 11.9 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Percentage of Participants with Immediate Related Unsolicited AE | 0 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Percentage of Participants with Immediate Solicited AEs | 7.7 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Solicited AE: Mild | 7.7 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Solicited AE: Moderate | 0 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Solicited AE: Severe | 0 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Solicited AE: Potentially life-threatening | 0 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Percentage of Participants with Immediate Unsolicited AE | 0 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Unsolicited AE: Mild | 0 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Unsolicited AE: Moderate | 0 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Unsolicited AE: Severe | 0 percentage of participants |
| Placebo | Percentage of Participants With Immediate Adverse Events (AEs) According to Severity, and Investigator-assessed Causality | Severity of Immediate Unsolicited AE: Potentially life-threatening | 0 percentage of participants |
Primary
Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths
AESIs include vaccine-associated enhanced diseases, hypersensitivity reactions, and potential immune-mediated diseases
Time frame: Within 21 days after each vaccination
Population: Safety population included all randomized subjects who received at least 1 dose of the investigational product.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with MAAEs | 3.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with AESIs | 2.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with AEs Leading to Study Withdrawal | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with Deaths | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with SAEs | 0 percentage of participants |
| Placebo | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with Deaths | 0 percentage of participants |
| Placebo | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with SAEs | 0 percentage of participants |
| Placebo | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with MAAEs | 11.5 percentage of participants |
| Placebo | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with AEs Leading to Study Withdrawal | 0 percentage of participants |
| Placebo | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with AESIs | 0 percentage of participants |
Primary
Percentage of Participants With Solicited AEs According to Severity
Solicited AEs are defined the following; (i) local AEs (injection site erythema, injection site swelling, injection site induration, and injection site pain) and (ii) systemic AEs (fever, headache, fatigue, muscle aches, joint aches, chills, a feeling of general discomfort, swelling in the axilla, and swelling in the neck)．
Time frame: Within 7 days after each vaccination
Population: Safety population included all randomized subjects who received at least 1 dose of the investigational product.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited AE: Mild | 60.4 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Local AE: Severe | 2.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited AE: Potentially life-threatening | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Local AE: Potentially life-threatening | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Percentage of Participants with Solicited AE | 91.1 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Percentage of Participants with Solicited Systemic AE | 70.3 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Percentage of Participants with Solicited Local AE | 85.1 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Systemic AE: Mild | 45.5 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited AE: Moderate | 24.8 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Systemic AE: Moderate | 20.8 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Local AE: Mild | 76.2 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Systemic AE: Severe | 3.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited AE: Severe | 5.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Systemic AE: Potentially life-threatening | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Local AE: Moderate | 6.9 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Systemic AE: Potentially life-threatening | 0 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Percentage of Participants with Solicited AE | 42.3 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited AE: Mild | 38.5 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited AE: Severe | 0 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited AE: Potentially life-threatening | 0 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Percentage of Participants with Solicited Local AE | 11.5 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Local AE: Mild | 11.5 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Local AE: Moderate | 0 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Local AE: Severe | 0 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Local AE: Potentially life-threatening | 0 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Percentage of Participants with Solicited Systemic AE | 38.5 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Systemic AE: Mild | 34.6 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Systemic AE: Moderate | 3.8 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited Systemic AE: Severe | 0 percentage of participants |
| Placebo | Percentage of Participants With Solicited AEs According to Severity | Severity of Solicited AE: Moderate | 3.8 percentage of participants |
Primary
Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality
Time frame: Within 21 days after each vaccination
Population: Safety population included all randomized subjects who received at least 1 dose of the investigational product.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Percentage of Participants with Unsolicited AEs | 18.8 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Severity of Unsolicited AE: Mild | 15.8 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Severity of Unsolicited AE: Moderate | 3.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Severity of Unsolicited AE: Severe | 0.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Severity of Unsolicited AE: Potentially life-threatening | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Percentage of Participants with Related Unsolicited AE | 12.9 percentage of participants |
| Placebo | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Severity of Unsolicited AE: Potentially life-threatening | 0 percentage of participants |
| Placebo | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Percentage of Participants with Unsolicited AEs | 26.9 percentage of participants |
| Placebo | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Severity of Unsolicited AE: Severe | 0 percentage of participants |
| Placebo | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Severity of Unsolicited AE: Mild | 26.9 percentage of participants |
| Placebo | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Percentage of Participants with Related Unsolicited AE | 0 percentage of participants |
| Placebo | Percentage of Participants With Unsolicited AEs According to Severity, and Investigator-assessed Causality | Severity of Unsolicited AE: Moderate | 0 percentage of participants |
Primary
SARS-CoV-2 Neutralizing Antibody (Nab) Responses
Seroconversion (SC) rate. SC rate is defined as the proportion of subjects achieving SC in the analysis set i.e. subjects with: * For subjects with detectable Nab titer at Day 0 (i.e. baseline Nab titer ≥10): a ≥ 4-fold increase in Nab titers between Day 0 and Day 21/42, respectively. * For subjects with undetectable Nab titer at Day 0 (i.e. baseline Nab titer \< 10): Nab titer of ≥ 40 on Day 21/42, respectively.
Time frame: Day 0 (before 1st vaccination), Day 21 (21 days after 1st vaccination and before 2nd vaccination), and Day 42 (21 days after 2nd vaccination)
Population: Immunogenicity Per Protocol population included all randomized subjects who do not have any major protocol violations, and who received the investigational product. For the Day 21 analysis, this included the subjects who received the first vaccine dose and had Day 0 and Day 21 immunogenicity sample collections. For the Day 42 analysis, this included the subjects who received both vaccine doses and had Day 0 and Day 42 immunogenicity sample collections.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses | Day 21 | 38.9 percentage of subjects achieving SC |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses | Day 42 | 99.0 percentage of subjects achieving SC |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses | Day 21 | 0 percentage of subjects achieving SC |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses | Day 42 | 0 percentage of subjects achieving SC |
Primary
SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR
Geometric mean fold rise (GMFR) is defined as the ratio of geometric mean antibody titer (GMT) based on that of Day 0 (i.e. Day 21/Day 0 and Day 42/Day 0).
Time frame: Day 21 (21 days after 1st vaccination and before 2nd vaccination), and Day 42 (21 days after 2nd vaccination)
Population: Immunogenicity Per Protocol population included all randomized subjects who do not have any major protocol violations, and who received the investigational product. For the Day 21 analysis, this included the subjects who received the first vaccine dose and had Day 0 and Day 21 immunogenicity sample collections. For the Day 42 analysis, this included the subjects who received both vaccine doses and had Day 0 and Day 42 immunogenicity sample collections.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR | GMFR: Day 21/Day 0 | 6.55 fold rise |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR | GMFR: Day 42/Day 0 | 136.75 fold rise |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR | GMFR: Day 21/Day 0 | 1.03 fold rise |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR | GMFR: Day 42/Day 0 | 1.04 fold rise |
Primary
SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT
Geometric mean neutralizing antibody titer (GMT)
Time frame: Day 0 (before 1st vaccination), Day 21 (21 days after 1st vaccination and before 2nd vaccination), and Day 42 (21 days after 2nd vaccination)
Population: Immunogenicity Per Protocol population included all randomized subjects who do not have any major protocol violations, and who received the investigational product. For the Day 21 analysis, this included the subjects who received the first vaccine dose and had Day 0 and Day 21 immunogenicity sample collections. For the Day 42 analysis, this included the subjects who received both vaccine doses and had Day 0 and Day 42 immunogenicity sample collections.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | GMT: Day 0 | 6.6 titer |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | GMT: Day 21 | 43.9 titer |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | GMT: Day 42 | 912.6 titer |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | GMT: Day 0 | 6.9 titer |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | GMT: Day 21 | 7.0 titer |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | GMT: Day 42 | 7.0 titer |
Primary
SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses
Using the interferon-γ enzyme-linked immunospot (ELISpot) assay. Unit of Measure: Spot-Forming Cell (SFC)/10\^6 Peripheral Blood Mononuclear Cells (PBMC)
Time frame: Day 0 (before 1st vaccination), Day 21 (21 days after 1st vaccination and before 2nd vaccination), and Day 42 (21 days after 2nd vaccination)
Population: Immunogenicity Per Protocol population included all randomized subjects who do not have any major protocol violations, and who received the investigational product. For the Day 21 analysis, this included the subjects who received the first vaccine dose and had Day 0 and Day 21 immunogenicity sample collections. For the Day 42 analysis, this included the subjects who received both vaccine doses and had Day 0 and Day 42 immunogenicity sample collections.
| Arm | Measure | Group | Value (MEDIAN) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses | Day 0 | 188.0 SFC/10^6 PBMC |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses | Day 21 | 265.5 SFC/10^6 PBMC |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses | Day 42 | 1173.0 SFC/10^6 PBMC |
| Placebo | SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses | Day 0 | 277.5 SFC/10^6 PBMC |
| Placebo | SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses | Day 21 | 330.0 SFC/10^6 PBMC |
| Placebo | SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses | Day 42 | 413.0 SFC/10^6 PBMC |
Primary
SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses
Using the interleukin-4 ELISpot assay
Time frame: Day 0 (before 1st vaccination), Day 21 (21 days after 1st vaccination and before 2nd vaccination), and Day 42 (21 days after 2nd vaccination)
Population: Immunogenicity Per Protocol population included all randomized subjects who do not have any major protocol violations, and who received the investigational product. For the Day 21 analysis, this included the subjects who received the first vaccine dose and had Day 0 and Day 21 immunogenicity sample collections. For the Day 42 analysis, this included the subjects who received both vaccine doses and had Day 0 and Day 42 immunogenicity sample collections.
| Arm | Measure | Group | Value (MEDIAN) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses | Day 0 | 0.0 SFC/10^6 PBMC |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses | Day 21 | 0.0 SFC/10^6 PBMC |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses | Day 42 | 619.0 SFC/10^6 PBMC |
| Placebo | SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses | Day 21 | 0.0 SFC/10^6 PBMC |
| Placebo | SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses | Day 0 | 0.0 SFC/10^6 PBMC |
| Placebo | SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses | Day 42 | 0.0 SFC/10^6 PBMC |
Secondary
Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths
AESIs include vaccine-associated enhanced diseases, hypersensitivity reactions, and potential immune-mediated diseases.
Time frame: Day 0 (after 1st vaccination) to end of study, on average the study duration by the termination is 334 days.
Population: Safety population included all randomized subjects who received at least 1 dose of the investigational product.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with MAAEs | 31.7 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with AESIs | 2.0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with AEs Leading to Study Withdrawal | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with Deaths | 0 percentage of participants |
| MT-2766 High Dose (3.75 µg) | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with SAEs | 2.0 percentage of participants |
| Placebo | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with Deaths | 0 percentage of participants |
| Placebo | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with SAEs | 7.7 percentage of participants |
| Placebo | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with MAAEs | 46.2 percentage of participants |
| Placebo | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with AEs Leading to Study Withdrawal | 0 percentage of participants |
| Placebo | Percentage of Participants With Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESIs), and Deaths | Percentage of Participants with AESIs | 0 percentage of participants |
Secondary
SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR
Geometric mean fold rise (GMFR)
Time frame: Day 128 and Day 201
Population: This analysis population included randomized subjects who had no major protocol violations and received investigational drug (MT-2766 n=100, Placebo n=26). For the Day 128, analysis included the subjects who received both doses and had Day 0 and 128 sample collections (MT-2766 n=94, Placebo n=25). For the Day 201, analysis included the subjects who received both doses and had Day 0 and 201 sample collections (MT-2766 n=90, Placebo n=22).
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR | GMFR: Day 128/Day 0 | 29.17 fold rise |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR | GMFR: Day 201/Day 0 | 22.63 fold rise |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR | GMFR: Day 128/Day 0 | 1.22 fold rise |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMFR | GMFR: Day 201/Day 0 | 1.17 fold rise |
Secondary
SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT
Geometric mean neutralizing antibody titer (GMT)
Time frame: Day 128 and Day 201
Population: This analysis population included randomized subjects who had no major protocol violations and received investigational drug (MT-2766 n=100, Placebo n=26). For the Day 128, analysis included the subjects who received both doses and had Day 0 and 128 sample collections (MT-2766 n=94, Placebo n=25). For the Day 201, analysis included the subjects who received both doses and had Day 0 and 201 sample collections (MT-2766 n=90, Placebo n=22).
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | GMT: Day 128 | 196.5 titer |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | GMT: Day 201 | 139.9 titer |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | GMT: Day 128 | 8.5 titer |
| Placebo | SARS-CoV-2 Neutralizing Antibody (Nab) Responses: GMT | GMT: Day 201 | 8.3 titer |
Secondary
SARS-CoV-2-specific Antibody Responses (Total IgG): GMFR
Geometric mean fold rise (GMFR)
Time frame: Day 0，Day 21，Day 42，Day 128 and Day 201
Population: This analysis population included randomized subjects who had no major protocol violations and received investigational drug (MT-2766 n=100, Placebo n=26). For the Day 21, analysis included the subjects who received the 1st dose and had Day 0 and 21 sample collections. For the Day 42, 128, and 201, analyses included the subjects who received two doses and had Day 0 and the each time point sample collections. See the table below for the number of analyzed subjects at each time point.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific Antibody Responses (Total IgG): GMFR | GMFR: Day 21/Day 0 | 22.34 fold rise |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific Antibody Responses (Total IgG): GMFR | GMFR: Day 42/Day 0 | 917.37 fold rise |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific Antibody Responses (Total IgG): GMFR | GMFR: Day 128/Day 0 | 245.38 fold rise |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific Antibody Responses (Total IgG): GMFR | GMFR: Day 201/Day 0 | 176.32 fold rise |
| Placebo | SARS-CoV-2-specific Antibody Responses (Total IgG): GMFR | GMFR: Day 201/Day 0 | 1.95 fold rise |
| Placebo | SARS-CoV-2-specific Antibody Responses (Total IgG): GMFR | GMFR: Day 21/Day 0 | 1.02 fold rise |
| Placebo | SARS-CoV-2-specific Antibody Responses (Total IgG): GMFR | GMFR: Day 128/Day 0 | 1.34 fold rise |
| Placebo | SARS-CoV-2-specific Antibody Responses (Total IgG): GMFR | GMFR: Day 42/Day 0 | 1.03 fold rise |
Secondary
SARS-CoV-2-specific Antibody Responses (Total IgG): GMT
Geometric mean neutralizing antibody titer (GMT)
Time frame: Day 0，Day 21，Day 42，Day 128 and Day 201
Population: This analysis population included randomized subjects who had no major protocol violations and received investigational drug (MT-2766 n=100, Placebo n=26). For the Day 21, analysis included the subjects who received the 1st dose and had Day 0 and 21 sample collections. For the Day 42, 128, and 201, analyses included the subjects who received two doses and had Day 0 and the each time point sample collections. See the table below for the number of analyzed subjects at each time point.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | GMT: Day 21 | 2258.3 titer |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | GMT: Day 128 | 24391.9 titer |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | GMT: Day 42 | 95159.8 titer |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | GMT: Day 201 | 15429.0 titer |
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | GMT: Day 0 | 103.6 titer |
| Placebo | SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | GMT: Day 201 | 216.6 titer |
| Placebo | SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | GMT: Day 0 | 119.5 titer |
| Placebo | SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | GMT: Day 21 | 118.6 titer |
| Placebo | SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | GMT: Day 42 | 114.3 titer |
| Placebo | SARS-CoV-2-specific Antibody Responses (Total IgG): GMT | GMT: Day 128 | 147.0 titer |
Secondary
SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses
Using the interferon-γ enzyme-linked immunospot (ELISpot) assay.
Time frame: Days 201
Population: Immunogenicity Per Protocol population included all randomized subjects who do not have any major protocol violations, and who received the investigational product. For the Day 128 analysis, this should include the subjects who received both vaccine doses and had Day 0 and Day 128 immunogenicity sample collections. For the Day 201 analysis, this should include the subjects who received both vaccine doses and had Day 0 and Day 201 immunogenicity sample collections.
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses | 948.0 SFC/10^6 PBMC |
| Placebo | SARS-CoV-2-specific T Helper 1 (Th1) Cell-mediated Immune (CMI) Responses | 171.50 SFC/10^6 PBMC |
Secondary
SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses
Using the interleukin-4 ELISpot assay
Time frame: Days 201
Population: Immunogenicity Per Protocol population included all randomized subjects who do not have any major protocol violations, and who received the investigational product. For the Day 128 analysis, this should include the subjects who received both vaccine doses and had Day 0 and Day 128 immunogenicity sample collections. For the Day 201 analysis, this should include the subjects who received both vaccine doses and had Day 0 and Day 201 immunogenicity sample collections.
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| MT-2766 High Dose (3.75 µg) | SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses | 375.0 SFC/10^6 PBMC |
| Placebo | SARS-CoV-2-specific T Helper 2 (Th2) CMI Responses | 0.0 SFC/10^6 PBMC |
Secondary
Seroconversion (SC) Rate of SARS-CoV-2 Neutralizing Antibody
SC rate is defined as the proportion of subjects achieving SC in the analysis set i.e. subjects with: * For subjects with detectable Nab titer at Day 0 (i.e. baseline Nab titer ≥10): a ≥ 4-fold increase in Nab titers between Day 0 and Day 128/201, respectively. * For subjects with undetectable Nab titer at Day 0 (i.e. baseline Nab titer \< 10): Nab titer of ≥ 40 on Day 128/201, respectively.
Time frame: Day 128 and Day 201
Population: This analysis population included randomized subjects who had no major protocol violations and received investigational drug (MT-2766 n=100, Placebo n=26). For the Day 128, analysis included the subjects who received both doses and had Day 0 and 128 sample collections (MT-2766 n=94, Placebo n=25). For the Day 201, analysis included the subjects who received both doses and had Day 0 and 201 sample collections (MT-2766 n=90, Placebo n=22).
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | Seroconversion (SC) Rate of SARS-CoV-2 Neutralizing Antibody | SC rate: Day 128 | 90.4 ％ |
| MT-2766 High Dose (3.75 µg) | Seroconversion (SC) Rate of SARS-CoV-2 Neutralizing Antibody | SC rate: Day 201 | 77.8 ％ |
| Placebo | Seroconversion (SC) Rate of SARS-CoV-2 Neutralizing Antibody | SC rate: Day 128 | 4.0 ％ |
| Placebo | Seroconversion (SC) Rate of SARS-CoV-2 Neutralizing Antibody | SC rate: Day 201 | 4.5 ％ |
Secondary
Seroconversion (SC) Rate of SARS-CoV-2-specific Antibody Responses (Total IgG):
SC rate is defined as the proportion of subjects achieving SC in the analysis set i.e. subjects with: * For subjects with detectable Nab titer at Day 0 (i.e. baseline Nab titer ≥10): a ≥ 4-fold increase in Nab titers between Day 0 and Day 21/42/128/201, respectively. * For subjects with undetectable Nab titer at Day 0 (i.e. baseline Nab titer \< 10): Nab titer of ≥ 40 on Day 21/42, respectively.
Time frame: Day 0，Day 21，Day 42，Day 128 and Day 201
Population: This analysis population included randomized subjects who had no major protocol violations and received investigational drug (MT-2766 n=100, Placebo n=26). For the Day 21, analysis included the subjects who received the 1st dose and had Day 0 and 21 sample collections. For the Day 42, 128, and 201, analyses included the subjects who received two doses and had Day 0 and the each time point sample collections. See the table below for the number of analyzed subjects at each time point.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| MT-2766 High Dose (3.75 µg) | Seroconversion (SC) Rate of SARS-CoV-2-specific Antibody Responses (Total IgG): | SC rate: Day 21 | 83.7 percentage of subjects achieving SC |
| MT-2766 High Dose (3.75 µg) | Seroconversion (SC) Rate of SARS-CoV-2-specific Antibody Responses (Total IgG): | SC rate: Day 42 | 97.9 percentage of subjects achieving SC |
| MT-2766 High Dose (3.75 µg) | Seroconversion (SC) Rate of SARS-CoV-2-specific Antibody Responses (Total IgG): | SC rate: Day 128 | 96.8 percentage of subjects achieving SC |
| MT-2766 High Dose (3.75 µg) | Seroconversion (SC) Rate of SARS-CoV-2-specific Antibody Responses (Total IgG): | SC rate: Day 201 | 95.6 percentage of subjects achieving SC |
| Placebo | Seroconversion (SC) Rate of SARS-CoV-2-specific Antibody Responses (Total IgG): | SC rate: Day 201 | 18.2 percentage of subjects achieving SC |
| Placebo | Seroconversion (SC) Rate of SARS-CoV-2-specific Antibody Responses (Total IgG): | SC rate: Day 21 | 0.0 percentage of subjects achieving SC |
| Placebo | Seroconversion (SC) Rate of SARS-CoV-2-specific Antibody Responses (Total IgG): | SC rate: Day 128 | 11.5 percentage of subjects achieving SC |
| Placebo | Seroconversion (SC) Rate of SARS-CoV-2-specific Antibody Responses (Total IgG): | SC rate: Day 42 | 0.0 percentage of subjects achieving SC |