Main Part: Geometric Mean Titers (GMT) Ratio of Neutralizing Antibody Titers to the Ancestral Strain (Wild-type Virus) on Day 15 Compared with that Observed on Day 36 in Participants from the TAK-019-1501 Study;Main Part: Percentage of Participants with Adverse Event of Special Interest (AESI) until Day 29;Main Part: Percentage of Participants with Any AE Leading to Participant's Withdrawal from the Trial until Day 29;Main Part: Percentage of Participants with Medically-Attended Adverse Events (MAAEs) until Day 29;Main Part: Percentage of Participants with Reported Solicited Local Adverse Events (AEs) for 7 Days Following the First Single Booster Vaccination;Main Part: Percentage of Participants with SARS-CoV-2 Infection until Day 29;Main Part: Percentage of Participants with Serious Adverse Events (SAE) until Day 29;Main Part: Percentage of Participants with Solicited Systemic AEs for 7 Days Following the First Single Booster Vaccination;Main Part: Percentage of Participants with Unsolicited AEs for 28 Days Following the First Single Booster Vaccination

Main Part: Geometric Mean Titers (GMT) Ratio of Neutralizing Antibody Titers to the Ancestral Strain (Wild-type Virus) on Day 15 Compared with that Observed on Day 36 in Participants from the TAK-019-1501 Study;Main Part: Percentage of Participants with Adverse Event of Special Interest (AESI) until Day 29;Main Part: Percentage of Participants with Any AE Leading to Participant's Withdrawal from the Trial until Day 29;Main Part: Percentage of Participants with Medically-Attended Adverse Events (MAAEs) until Day 29;Main Part: Percentage of Participants with Reported Solicited Local Adverse Events (AEs) for 7 Days Following the First Single Booster Vaccination;Main Part: Percentage of Participants with SARS-CoV-2 Infection until Day 29;Main Part: Percentage of Participants with Serious Adverse Events (SAE) until Day 29;Main Part: Percentage of Participants with Solicited Systemic AEs for 7 Days Following the First Single Booster Vaccination;Main Part: Percentage of Participants with Unsolicited AEs for 28 Days Following the First Single Booster Vaccination

Geometric Mean Titers (GMT) Ratio of Neutralizing Antibody Titers to the Ancestral Strain (Wild-type Virus) on Day 15 Compared with that Observed on Day 36 in Participants from the TAK-019-1501 Study;Percentage of Participants with Adverse Event of Special Interest (AESI) until Day 29;Percentage of Participants with Any AE Leading to Participant's Withdrawal from the Trial until Day 29;Percentage of Participants with Medically-Attended Adverse Events (MAAEs) until Day 29;Percentage of Participants with Reported Solicited Local Adverse Events (AEs) for 7 Days Following Booster Vaccination;Percentage of Participants with SARS-CoV-2 Infection until Day 29;Percentage of Participants with Serious Adverse Events (SAE) until Day 29;Percentage of Participants with Solicited Systemic AEs for 7 Days Following Booster Vaccination;Percentage of Participants with Unsolicited AEs for 28 Days Following Booster Vaccination

Geometric Mean Titers (GMT) Ratio of Neutralizing Antibody Titers to the Ancestral Strain (Wild-type Virus) on Day 15 Compared with that Observed on Day 36 in Participants from the TAK-019-1501 Study;Percentage of Participants with Adverse Event of Special Interest (AESI) until Day 29;Percentage of Participants with Any AE Leading to Participant's Withdrawal from the Trial until Day 29;Percentage of Participants with Medically-Attended Adverse Events (MAAEs) until Day 29;Percentage of Participants with Reported Solicited Local Adverse Events (AEs) for 7 Days Following Booster Vaccination;Percentage of Participants with SARS-CoV-2 Infection until Day 29;Percentage of Participants with Serious Adverse Events (SAE) until Day 29;Percentage of Participants with Solicited Systemic AEs for 7 Days Following Booster Vaccination;Percentage of Participants with Unsolicited AEs for 28 Days Following Booster Vaccination