Trial Outcomes & Findings for A Study to Learn About New COVD-19 RNA Vaccine Candidates for New Variants in Healthy Individuals (NCT NCT05997290)

In this study there were 3 sub-studies: sub-study A (SSA), sub-study B (SSB), and sub-study C (SSC).

SSA: A total of 417 participants were assigned, out of which 412 were vaccinated. SSB: A total of 311 participants were assigned and vaccinated. SSC: A total of 321 participants were assigned, out of which 318 were vaccinated. As per study objectives, arms for SSC cohort 1 and 2 have been combined.

A Study to Learn About New COVD-19 RNA Vaccine Candidates for New Variants in Healthy Individuals

Local reactions: pain at injection site, redness and swelling were recorded by participants in an electronic diary (e-diary) or as adverse events (AEs) in the case report form (CRF). Redness and swelling were recorded in measuring device units (mdu) (range: 1 to 21), 1 mdu =0.5 centimeter (cm) and were graded as mild (greater than \[\>\] 2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm), severe (\>10.0 cm) and Grade 4 (necrosis \[swelling\] and necrosis or exfoliative dermatitis \[redness\]). Pain at injection site was graded as mild (did not interfere with activity), moderate (interfered with activity), severe (prevented daily activity) and Grade 4 (emergency room \[ER\] visit or hospitalization for severe pain at injection site). Grade 4 local reactions were classified by investigator or medically qualified person.

Systemic events were recorded by participants in an e-diary or as AEs in the CRF. Fever: defined as oral temperature more than or equal to (\>=38) degree Celsius (C) and categorized as \>= 38.0 to 38.4 degree C, \>38.4 to 38.9 degree C, \>38.9 to 40.0 degree C and \>40.0 degree C. Fatigue, headache, chills, new or worsened muscle pain and joint pain were graded as: mild (did not interfere with activity), moderate (some interference with activity), severe (prevented daily routine activity). Vomiting: mild: 1-2 times in 24 hours (h), moderate: \>2 times in 24h, severe: required intravenous (IV) hydration. Diarrhea was graded as: mild: 2-3 loose stools in 24h, moderate: 4-5 loose stools in 24h, severe: 6 or more loose stools in 24h. Grade 4 for all events except fever: ER visit/hospitalization. Grade 4 systemic events were classified by investigator or medically qualified person.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with use of study intervention, whether or not considered related to study intervention. A serious AE (SAE) was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event. AEs included both SAEs and all non-SAEs. Only AEs collected by non-systematic assessment (i.e., excluding local reactions and systemic events) were reported in this outcome measure.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event.

GMTs and 2-sided 95 percentage (%) confidence interval (CIs) were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the lower limit of quantitation (LLOQ) were set to 0.5\*LLOQ.

GMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ.

GMFRs were defined as geometric mean ratios of the results after vaccination to the results before vaccination. GMFR and 2-sided 95% CI were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ.

GMFRs were defined as geometric mean ratios of the results after vaccination to the results before vaccination. GMFR and 2-sided 95% CI were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ.

Seroresponse was defined as achieving \>= 4-fold rise from baseline (before the study vaccination). If the baseline measurement was below the LLOQ, the postvaccination assay result of \>= 4\* LLOQ was considered a seroresponse.

Seroresponse was defined as achieving \>= 4-fold rise from baseline (before the study vaccination). If the baseline measurement was below the LLOQ, the postvaccination assay result of \>= 4\* LLOQ was considered a seroresponse.

Local reactions: pain at injection site, redness and swelling were recorded by participants in an e-diary or as AEs in the CRF. Redness and swelling were recorded in mdu (range:1 to 21), 1 mdu= 0.5 cm and were graded as mild (\>2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm), severe (\>10.0 cm) and Grade 4 (necrosis \[swelling\] and necrosis or exfoliative dermatitis \[redness\]). Pain at injection site was graded as mild (did not interfere with activity), moderate (interfered with activity), severe (prevented daily activity) and Grade 4 (ER visit or hospitalization for severe pain at injection site). Grade 4 local reactions were classified by investigator or medically qualified person.

Systemic events were recorded by participants in an e-diary or as AEs in the CRF. Fever: defined as oral temperature \>=38 degree C and categorized as \>= 38.0 to 38.4 degree C, \>38.4 to 38.9 degree C, \>38.9 to 40.0 degree C and \>40.0 degree C. Fatigue, headache, chills, new or worsened muscle pain and joint pain were graded as: mild (didn't interfere with activity), moderate (some interference with activity), severe (prevented daily routine activity). Vomiting: mild: 1-2 times in 24h, moderate: \>2 times in 24h, severe: required IV hydration. Diarrhea were graded as: mild: 2-3 loose stools in 24h, moderate: 4-5 loose stools in 24h, severe: 6 or more loose stools in 24h. Grade 4 for all events except fever: ER visit/hospitalization. Grade 4 systemic events were classified by investigator or medically qualified person.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with use of study intervention, whether or not considered related to study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event. AEs included both SAEs and all non-SAEs. Only AEs collected by non-systematic assessment (i.e., excluding local reactions and systemic events) were reported in this outcome measure.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event.

GMTs / GMRs and 2-sided 95% CIs were calculated by exponentiating the least square (LS) means / difference of LS means and the corresponding CIs based on analysis of log-transformed assay results using a linear regression model with baseline assay results (log scale), age and vaccine group as covariates. Assay results below the LLOQ were set to 0.5\*LLOQ. GMT was reported in descriptive section and GMR was reported in statistical analysis section

Seroresponse was defined as achieving \>=4-fold rise from baseline (before the study vaccination). If the baseline measurement was below the LLOQ, the postvaccination assay result of \>= 4\* LLOQ was considered a seroresponse. Percentage of participants with seroresponse were reported in descriptive section and difference in percentage of participants with seroresponse in SSB: All Age Groups (Vaccine Naive)- SSA: All Age Groups (Vaccine Experienced Control) were reported in statistical analysis section.

Local reactions: pain at injection site, redness and swelling were recorded by participants in an e-diary or as AEs in the CRF. Redness and swelling were recorded in mdu (range:1 to 21), 1 mdu= 0.5 cm and were graded as mild (\>2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm), severe (\>10.0 cm) and Grade 4 (necrosis \[swelling\] and necrosis or exfoliative dermatitis \[redness\]). Pain at injection site was graded as mild (did not interfere with activity), moderate (interfered with activity), severe (prevented daily activity) and Grade 4 (ER visit or hospitalization for severe pain at injection site). Grade 4 local reactions were classified by investigator or medically qualified person.

Systemic events were recorded by participants in an e-diary or as AEs in the CRF. Fever: defined as oral temperature \>=38 degree C and categorized as \>= 38.0 to 38.4 degree C, \>38.4 to 38.9 degree C, \>38.9 to 40.0 degree C and \>40.0 degree C. Fatigue, headache, chills, new or worsened muscle pain and joint pain were graded as: mild (didn't interfere with activity), moderate (some interference with activity), severe (prevented daily routine activity). Vomiting: mild: 1-2 times in 24h, moderate: \>2 times in 24h, severe: required IV hydration. Diarrhea were graded as: mild: 2-3 loose stools in 24h, moderate: 4-5 loose stools in 24h, severe: 6 or more loose stools in 24h. Grade 4 for all events except fever: ER visit/hospitalization. Grade 4 systemic events were classified by investigator or medically qualified person.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with use of study intervention, whether or not considered related to study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event. AEs included both SAEs and all non-SAEs. Only AEs collected by non-systematic assessment (i.e., excluding local reactions and systemic events) were reported in this outcome measure.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event.

Local reactions: pain at injection site, redness and swelling were recorded by participants in an e-diary or as AEs in the CRF. Redness and swelling were recorded in mdu (range:1 to 21), 1 mdu= 0.5 cm and were graded as mild (\>2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm), severe (\>10.0 cm) and Grade 4 (necrosis \[swelling\] and necrosis or exfoliative dermatitis \[redness\]). Pain at injection site was graded as mild (did not interfere with activity), moderate (interfered with activity), severe (prevented daily activity) and Grade 4 (ER visit or hospitalization for severe pain at injection site). Grade 4 local reactions were classified by investigator or medically qualified person.

Systemic events were recorded by participants in an e-diary or as AEs in the CRF. Fever: defined as oral temperature \>=38 deg C and categorized as \>= 38.0-38.4 deg C, \>38.4-38.9 deg C, \>38.9-40.0 deg C and \>40.0 deg C. Fatigue, headache, chills, new or worsened muscle pain and joint pain: mild (didn't interfere with activity), moderate (some interference with activity), severe (prevented daily routine activity). Vomiting: mild: 1-2 times in 24h, moderate: \>2 times in 24h, severe: required IV hydration. Diarrhea: mild: 2-3 loose stools in 24h, moderate: 4-5 loose stools in 24h, severe: 6 or more loose stools in 24h. Grade 4 for all events except fever: ER visit/hospitalization. Grade 4 events were classified by investigator or medically qualified person.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with use of study intervention, whether or not considered related to study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event. AEs included both SAEs and all non-SAEs. Only AEs collected by non-systematic assessment (i.e., excluding local reactions and systemic events) were reported in this outcome measure.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event.

GMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ.

GMFRs were defined as geometric mean ratios of the results after vaccination to the results before vaccination. GMFRs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ in the analysis.