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A Study of Ad26.COV2.S for the Prevention of SARS-CoV-2-Mediated COVID-19 in Adult Participants

A Randomized, Double-blind, Placebo-controlled Phase 3 Study to Assess the Efficacy and Safety of Ad26.COV2.S for the Prevention of SARS-CoV-2-mediated COVID-19 in Adults Aged 18 Years and Older

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04505722
Acronym
ENSEMBLE
Enrollment
44325
Registered
2020-08-10
Start date
2020-09-07
Completion date
2023-03-31
Last updated
2025-02-04

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

Conditions

Participants With or Without Stable Co-morbidities Associated With Progression to Severe COVID-19 at Different Stages of the Protocol

Keywords

Prevention, Vaccine

Brief summary

The study will evaluate the efficacy of Ad26.COV2.S in the prevention of molecularly confirmed moderate to severe/critical COVID-19, as compared to placebo, in adult participants.

Interventions

BIOLOGICALAd26.COV2.S

Ad26.COV2.S will be administered at a single dose of 5\*10\^10 virus particles (vp) on Day 1 (or Month 6 for placebo recipients) and as a single booster dose at Year 1.

OTHERPlacebo

Participants will receive Placebo.

Sponsors

Janssen Vaccines & Prevention B.V.
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* Contraceptive (birth control) use should be consistent with local regulations regarding the acceptable methods of contraception for those participating in clinical studies * All participants of childbearing potential must: have a negative highly sensitive urine pregnancy test at screening; and have a negative highly sensitive urine pregnancy test immediately prior to each study vaccine administration * Participant agrees to not donate bone marrow, blood, and blood products from the first study vaccine administration until 3 months after receiving the last dose of study vaccine * Must be willing to provide verifiable identification, has means to be contacted and to contact the investigator during the study * Must be able to read, understand, and complete questionnaires in the electronic clinical outcome assessment (eCOA) (that is, the coronavirus disease-2019 \[COVID 19\] signs and symptoms surveillance question, the e-Diary, and the electronic patient-reported outcomes (ePROs). Note: Participants with visual impairment are eligible for study participation and may have caregiver assistance in completing the electronic clinical outcome assessment (eCOA) questionnaires

Exclusion criteria

* Participant has a clinically significant acute illness (this does not include minor illnesses such as diarrhea or mild upper respiratory tract infection) or temperature greater than or equal to (\>=) 38.0 degree Celsius (100.4-degree Fahrenheit) within 24 hours prior to the planned first dose of study vaccine; randomization at a later date is permitted at the discretion of the investigator and after consultation with the sponsor * Participant received or plans to receive: (a) licensed live attenuated vaccines - within 28 days before or after planned administration of study vaccine ; and (b) other licensed (not live) vaccines - within 14 days before or after planned administration of study vaccine * Participant previously received a coronavirus vaccine * Participant received an investigational drug (including investigational drugs for prophylaxis of COVID-19) within 30 days or used an invasive investigational medical device within 30 days or received investigational immunoglobulin (Ig) or monoclonal antibodies within 3 months, or received convalescent serum for COVID-19 treatment within 4 months or received an investigational vaccine (including investigational Adenoviral-vectored vaccines) within 6 months before the planned administration of the first dose of study vaccine or is currently enrolled or plans to participate in another investigational study during the course of this study

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical Coronavirus Disease (COVID-19) With Seronegative Status With Onset at Least 14 Days After Double-blind Vaccination on Day 1 (Day 15): Double-blind PhaseFrom 14 days after double-blind vaccination on Day 1 (Day 15) up to Month 6Molecularly confirmed moderate to severe/critical COVID-19 was defined as a severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) positive reverse transcription/polymerase chain reaction (RT-PCR) or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>= 20 breaths per minute and symptoms such as shortness of breath or two signs or symptoms such as heart rate \>= 90 beats per minute (beats/minute) and symptoms such as cough from a list of signs and symptoms and severe/critical included one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute, oxygen saturation (SpO2) \<= 93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance.
Number of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind PhaseFrom 28 days after double-blind vaccination on Day 1 (Day 29) up to Month 6Molecularly confirmed moderate to severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>=20 breaths per minute and symptoms such as shortness of breath or two signs or symptoms such as heart rate \>= 90 beats/minute and symptoms such as cough from a list of signs and symptoms and severe/critical included one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute, SpO2 less than or equal to (\<=) 93 percent (%) on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the Intensive Care Unit (ICU), death defined as per Food and Drug Administration (FDA) guidance.
Number of Participants With Solicited Local Adverse Events (AEs) Up to 7 Days After Booster Vaccination (Open-label Booster Vaccination Phase)Up to Day 372 (7 Days after booster vaccination on Day 365 [Year 1])Participants who received the booster dose were asked to note in the e-Diary occurrences of injection site pain/tenderness, erythema, and swelling at the study vaccine injection site daily for 7 days post-booster vaccination (day of vaccination and the subsequent 7 days).
Number of Participants With Solicited Systemic AEs Up to 7 Days After Booster Vaccination (Open-label Booster Vaccination Phase)Up to Day 372 (7 Days after booster vaccination on Day 365 [Year 1])Participants recorded the temperature in the e-Diary in the evening of the day of vaccination, and then daily for the next 7 days approximately at the same time each day. If more than 1 measurement was made on any given day, the highest temperature of that day was recorded in the e-Diary. Fever was defined as endogenous elevation of body temperature \>= 38.0 degree Celsius or \>=100.4-degree Fahrenheit, as recorded in at least 1 measurement. Participants also noted the signs and symptoms in the e-Diary on a daily basis for 7 days post-booster vaccination (day of vaccination and the subsequent 7 days), if feasible, for the following events: fatigue, headache, nausea, myalgia.
Number of Participants With Unsolicited AEs Up to 28 Days After Booster Vaccination (Open-label Booster Vaccination Phase)Up to Day 393 (28 Days after booster vaccination on Day 365 [Year 1])Unsolicited AEs were all AEs for which the participant is not specifically questioned in the participant diary.

Secondary

MeasureTime frameDescription
Number of Participants With First Occurrence of Molecularly Confirmed Mild COVID-19 (Double Blind Phase14 Days after double-blind vaccination on Day1 (Day 15)Molecularly confirmed mild Covid-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample and one of the following signs and symptoms: fever (\>=38°C or \>=100.4°F), sore throat, malaise (loss of appetite, generally unwell, fatigue, physical weakness), headache, muscle pain (myalgia), gastrointestinal symptoms, cough, chest congestion, runny nose, wheezing, skin rash, eye irritation or discharge, chills, new or changing olfactory or taste disorders, red or bruised looking feet or toes, or shaking chills or rigors.
Number of Participants With MAAEs Leading to Study Discontinuation (Double Blind Phase)Up to 35 weeksMAAEs were defined as AEs with medically-attended visits including hospital, emergency room, urgent care clinic, or other visits to or from medical personnel for any reason. Routine study visits were not considered medically-attended visits. New onset of chronic diseases was collected as part of the MAAEs.
Number of Participants With First Occurrence of Molecularly Confirmed Mild COVID-19 (Double Blind Phase)28 Days after double-blind vaccination on Day 1 (Day 29)Molecularly confirmed mild Covid-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample and one of the following signs and symptoms: fever (\>=38°C or \>=100.4°F), sore throat, malaise (loss of appetite, generally unwell, fatigue, physical weakness), headache, muscle pain (myalgia), gastrointestinal symptoms, cough, chest congestion, runny nose, wheezing, skin rash, eye irritation or discharge, chills, new or changing olfactory or taste disorders, red or bruised looking feet or toes, or shaking chills or rigors.
Number of Participants With First Occurrence of Molecularly Confirmed COVID-19 Defined by the US Food and Drug Administration (FDA) Harmonized Case Definition (Double Blind Phase)14 Days after double-blind vaccination on Day 1 (Day 15)Molecularly confirmed COVID-19 was defined as a positive SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample; and COVID-19 symptoms consistent with those defined by the US FDA harmonized case definition at the time of finalization of the study protocol: fever or chills, cough, shortness of breath or difficulty breathing, fatigue, muscle or body aches, headache, new loss of taste or smell, sore throat, congestion or runny nose, nausea or vomiting, diarrhea.
Number of Participants With Burden of Disease (BOD) Based on First Occurrence of Molecularly Confirmed Symptomatic COVID-19 (Double Blind Phase)14 Days after double-blind vaccination on Day 1 (Day 15)BOD is a weighted version of the mild, moderate, and severe/critical vaccine efficacies and was evaluated based on the first occurrence of molecularly confirmed COVID-19, including mild, moderate or severe/critical COVID-19 case.
Number of Participants With BOD Based on First Occurrence of Molecularly Confirmed Symptomatic COVID-19 (Double Blind Phase)28 Days after double-blind vaccination on Day 1 (Day 29)BOD is a weighted version of the mild, moderate, and severe/critical vaccine efficacies and was evaluated based on the first occurrence of molecularly confirmed COVID-19, including mild, moderate or severe/critical COVID-19 case.
Number of Participants With SARS-CoV-2 Seroconversion Based on Antibodies to N Protein Using ELISA and/or SARS-CoV-2 Immunoglobulin Assay (Double Blind Phase)From Day 29 until end of double-blind phase at Month 6Number of participants with SARS-CoV-2 seroconversion based on antibodies to nucleocapsid (N) protein using enzyme-linked immunosorbent assay (ELISA) and/or SARS-CoV- 2 immunoglobulin assay that is dependent on the SARS-CoV-2 N protein was reported.
Number of Participants With Asymptomatic Infection Detected by RT-PCR at the Time of the Month 6/Unblinding Visit (Double Blind Phase)Month 6Number of participants with asymptomatic infection detected by RT-PCR at the time of the Month 6/unblinding visit were reported.
Number of Participants With First Occurrence of SARS-CoV-2 Infection (Serologically and/or Molecularly Confirmed) (Double Blind Phase)28 days after double-blind vaccination on Day 1 (Day 29)Number of participants with first occurrence of SARS-CoV-2 infection (serologically and/or molecularly confirmed) were reported.
Number of Participants With First Occurrence of Molecularly Confirmed Severe/Critical COVID-19 With Seronegative Status With Onset at Least 14 Days After Double-blind Vaccination on Day 1 (Day 15): Double-blind PhaseFrom 14 days after double-blind vaccination on Day 1 (Day 15) up to Month 6Molecularly confirmed severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample and one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute,SpO2 \<=93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance. Seronegative is defined as N-serology seronegative at the time of boosting or at the Year 1 visit if not boosted.
Number of Participants With Serious Adverse Events (SAEs) (Double Blind Phase)Baseline (Day 1) up to 35 weeksAn AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. SAE is any untoward medical occurrence that at any dose may result in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, is a suspected transmission of any infectious agent via a medicinal product.
Number of Participants With Adverse Events of Special Interest (AESI) (Double Blind Phase)Baseline (Day 1) up to 35 weeksNumber of participants with AESIs were reported. AESIs are significant AEs that are judged to be of special interest because of clinical importance, known or suspected class effects, or based on nonclinical signals. Thrombosis with Thrombocytopenia Syndrome (TTS), a syndrome characterized by a combination of both a thrombotic event and thrombocytopenia, is considered to be an AESI in this study. A suspected TTS case is defined as: Thrombotic events: suspected deep vessel venous or arterial thrombotic events; Thrombocytopenia, defined as platelet count below 150,000/micro liter.
Number of Participants With Medically-Attended Adverse Events (MAAEs) (Double Blind Phase)Up to 6 months after double-blind vaccination on Day 1 (up to 6 months)An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. MAAEs were defined as AEs with medically-attended visits including hospital, emergency room, urgent care clinic, or other visits to or from medical personnel for any reason.
Number of Participants With Solicited Local Adverse Events (AEs) During 7 Days Following Vaccination (Double Blind Phase)Up to Day 8 (7 Days after double-blind vaccination on Day 1)An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Participants who were enrolled in safety subset were asked to note in the e-Diary occurrences of injection site pain/tenderness, erythema, and swelling at the study vaccine injection site daily for 7 days post-vaccination (day of vaccination and the subsequent 7 days).
Number of Participants With Solicited Systemic AEs During 7 Days Following Vaccination (Double Blind Phase)Up to Day 8 (7 Days after double-blind vaccination on Day 1)An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with pharmaceutical/biological agent under study. Participants who were enrolled in safety subset were instructed on how to record daily temperature using a thermometer provided for home use. Participants recorded the temperature in the e-Diary in the evening of the day of vaccination, and then daily for the next 7 days approximately at the same time each day. If more than 1 measurement was made on any given day, the highest temperature of that day was recorded in the e-Diary. Fever was defined as endogenous elevation of body temperature \>= 38.0 degree Celsius or \>=100.4-degree Fahrenheit, as recorded in at least 1 measurement. Participants also noted the signs and symptoms in the e-Diary on a daily basis for 7 days post vaccination (day of vaccination and the subsequent 7 days), for the following events: fatigue, headache, nausea, myalgia.
Number of Participants With Unsolicited AEs During 28 Days Post-vaccination (Double Blind Phase)Up to Day 29 (28 Days after double-blind vaccination on Day 1)An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Unsolicited AEs were all AEs for which the participant is not specifically questioned in the participant diary.
Binding Antibodies to SARS-CoV-2 S Protein Assessed by ELISA (Double Blind Phase)Baseline (Day 1), Day 29, and Day 71Binding antibodies to SARS-CoV-2 S protein as assessed by enzyme-linked immunosorbent assay (ELISA) to measure humoral immune response was reported. The lower limit of quantification (LLOQ) and upper limit of quantification (ULOQ) were 50.3 EU/mL and 58,158.10 EU/mL, respectively. A sample was considered positive if the value was strictly greater than the LLOQ (\>LLOQ).
Number of Participants With Antibody Titers to Ad26.COV2.S (Booster Phase)28 days after booster vaccination on Day 365 (up to Day 393)Number of participants with antibody titers to Ad26.COV2.S to measure immune response were reported.
Number of Participants With Binding Antibodies to SARS- CoV-2S Protein as Measured by ELISA (Booster Phase)29 days after booster vaccination on Day 365 (Day 394)Number of participants with binding antibodies to SARS- CoV-2S protein as measured by ELISA was reported.
Number of Participants With First Occurrence of Molecularly Confirmed, Moderate to Severe/Critical COVID-19 for Seronegative Participants (Double Blind Phase)1 day after double-blind vaccination on Day 1 (Day 2)Molecularly confirmed moderate to severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>= 20 breaths per minute and symptoms such as shortness of breath or two signs or symptoms such as heart rate \>= 90 beats per minute (beats/minute) and symptoms such as cough from a list of signs and symptoms and severe/critical included one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute,SpO2 \<=93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance. Seronegative is defined as N-serology seronegative at the time of boosting or at the Year 1 visit if not boosted.
Number of Participants With First Occurrence of Molecularly Confirmed Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind PhaseFrom 28 days after double-blind vaccination on Day 1 (Day 29) up to Month 6Severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample and one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute,SpO2 \<=93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance.
Number of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 Regardless of Their Serostatus (Double Blind Phase)1 day after double-blind vaccination on Day 1 (Day 2)Molecularly confirmed moderate to severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>= 20 breaths per minute and symptoms such as shortness of breath or two signs or symptoms such as heart rate \>= 90 beats per minute (beats/minute) and symptoms such as cough from a list of signs and symptoms and severe/critical included one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute,SpO2 \<=93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance.
Number of Participants With First Occurrence of COVID-19 Requiring Medical Intervention (Double Blind Phase)14 days after double-blind vaccination on Day 1 (Day 15)Number of participants with first occurrence of COVID-19 requiring medical intervention (such as a composite endpoint of hospitalization, ICU admission, mechanical ventilation, and extracorporeal membrane oxygenation \[ECMO\], linked to objective measures such as decreased oxygenation, X-ray or computed tomography \[CT\] findings) or linked to any molecularly confirmed, COVID-19 at least 14 days post vaccination were reported.
Area Under the Curve (AUC) of SARS-CoV-2 Viral Load as Assessed by Quantitative Reverse-Transcriptase Polymerase Chain Reaction (RT-PCR) in Participants With Molecularly Confirmed, Moderate to Severe/Critical COVID-19 (Double Blind Phase)From Day 15 to end of the COVID-19 episode (Day 189)AUC of SARS-CoV-2 Viral Load was assessed in confirmed COVID-19 cases using RT-PCR. Nasal swabs were used to detect and/or quantify SARS-CoV-2.

Countries

Argentina, Brazil, Chile, Colombia, Mexico, Peru, South Africa, United States

Participant flow

Recruitment details

A total of 44325 participants were randomized, of which 1 participant was randomized in error due to lack of a signed informed consent form. This participant has not been included in the analysis.

Pre-assignment details

Due to change in the planned analysis, combined data of double blind (DB) and open label (OL) phase was collected and analyzed after completion of the double-blind phase. Results of safety outcome measures (OMs) were also collected and analyzed for combined DB and OL phase. Hence, safety data is reported only in adverse event section and not repeated in the OMs section. In all-cause mortality section out of 324 deaths, 1 death was not related to Adverse event.

Participants by arm

ArmCount
Double-blind Phase: Ad26.COV2.S 5*10^10 vp
Participants received intramuscular (IM) injection of Ad26.COV2.S at a dose level of 5\*10\^10 virus particles (vp) as single dose vaccine on Day 1.
21,898
Double-blind Phase: Placebo
Participants received IM injection of placebo matching to Ad26.COV2.S on Day 1.
21,890
Total43,788

Withdrawals & dropouts

PeriodReasonFG000FG001FG002
DB + OL Phase (2 Years 6.5 Months)Adverse Event006
DB + OL Phase (2 Years 6.5 Months)Death00324
DB + OL Phase (2 Years 6.5 Months)Lost to Follow-up004,978
DB + OL Phase (2 Years 6.5 Months)Other002,211
DB + OL Phase (2 Years 6.5 Months)Physician Decision00342
DB + OL Phase (2 Years 6.5 Months)Protocol Violation002
DB + OL Phase (2 Years 6.5 Months)Withdrawal by Subject004,332
DB Phase (Day 1 up to 6 Months)Adverse Event120
DB Phase (Day 1 up to 6 Months)Death34630
DB Phase (Day 1 up to 6 Months)Lost to Follow-up2713330
DB Phase (Day 1 up to 6 Months)Other61980
DB Phase (Day 1 up to 6 Months)Physician Decision17170
DB Phase (Day 1 up to 6 Months)Protocol Violation010
DB Phase (Day 1 up to 6 Months)Randomized not vaccinated2762600
DB Phase (Day 1 up to 6 Months)Withdrawal by Subject3767140

Baseline characteristics

CharacteristicDouble-blind Phase: Ad26.COV2.S 5*10^10 vpDouble-blind Phase: PlaceboTotal
Age, Continuous50.7 years
STANDARD_DEVIATION 15.08
50.7 years
STANDARD_DEVIATION 15.04
50.7 years
STANDARD_DEVIATION 15.06
Ethnicity (NIH/OMB)
Hispanic or Latino
9875 Participants9964 Participants19839 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
11476 Participants11367 Participants22843 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
547 Participants559 Participants1106 Participants
Race (NIH/OMB)
American Indian or Alaska Native
2083 Participants2060 Participants4143 Participants
Race (NIH/OMB)
Asian
743 Participants686 Participants1429 Participants
Race (NIH/OMB)
Black or African American
4253 Participants4262 Participants8515 Participants
Race (NIH/OMB)
More than one race
1207 Participants1248 Participants2455 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
56 Participants47 Participants103 Participants
Race (NIH/OMB)
Unknown or Not Reported
698 Participants744 Participants1442 Participants
Race (NIH/OMB)
White
12858 Participants12843 Participants25701 Participants
Region of Enrollment
ARGENTINA
1498 participants1498 participants2996 participants
Region of Enrollment
BRAZIL
3644 participants3635 participants7279 participants
Region of Enrollment
CHILE
563 participants570 participants1133 participants
Region of Enrollment
COLOMBIA
2125 participants2123 participants4248 participants
Region of Enrollment
MEXICO
238 participants241 participants479 participants
Region of Enrollment
PERU
886 participants885 participants1771 participants
Region of Enrollment
SOUTH AFRICA
3287 participants3289 participants6576 participants
Region of Enrollment
UNITED STATES
9657 participants9649 participants19306 participants
Sex/Gender, Customized
Female
9828 Participants9907 Participants19735 Participants
Sex/Gender, Customized
Male
12067 Participants11979 Participants24046 Participants
Sex/Gender, Customized
Undifferentiated
2 Participants4 Participants6 Participants
Sex/Gender, Customized
Unknown
1 Participants0 Participants1 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
EG004
affected / at risk
EG005
affected / at risk
deaths
Total, all-cause mortality
36 / 21,89864 / 21,890324 / 43,7880 / 00 / 00 / 0
other
Total, other adverse events
2,451 / 3,3561,653 / 3,3800 / 06,048 / 22,213190 / 613315 / 943
serious
Total, serious adverse events
235 / 21,898358 / 21,8902,758 / 43,7880 / 00 / 00 / 0

Outcome results

Primary

Number of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical Coronavirus Disease (COVID-19) With Seronegative Status With Onset at Least 14 Days After Double-blind Vaccination on Day 1 (Day 15): Double-blind Phase

Molecularly confirmed moderate to severe/critical COVID-19 was defined as a severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) positive reverse transcription/polymerase chain reaction (RT-PCR) or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>= 20 breaths per minute and symptoms such as shortness of breath or two signs or symptoms such as heart rate \>= 90 beats per minute (beats/minute) and symptoms such as cough from a list of signs and symptoms and severe/critical included one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute, oxygen saturation (SpO2) \<= 93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance.

Time frame: From 14 days after double-blind vaccination on Day 1 (Day 15) up to Month 6

Population: Per-protocol Efficacy (PP) set: participants of the FAS (all randomized participants with double-blind study vaccine administration, regardless of protocol deviations and serostatus at enrollment) who received double-blind study vaccine and who were seronegative at the time of vaccination and who had no other major protocol deviations to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 14 in PP set were excluded.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical Coronavirus Disease (COVID-19) With Seronegative Status With Onset at Least 14 Days After Double-blind Vaccination on Day 1 (Day 15): Double-blind PhaseAge: 18-59 years381 Participants
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical Coronavirus Disease (COVID-19) With Seronegative Status With Onset at Least 14 Days After Double-blind Vaccination on Day 1 (Day 15): Double-blind PhaseAge: Greater than or equal to (>=) 60 years103 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical Coronavirus Disease (COVID-19) With Seronegative Status With Onset at Least 14 Days After Double-blind Vaccination on Day 1 (Day 15): Double-blind PhaseAge: 18-59 years847 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical Coronavirus Disease (COVID-19) With Seronegative Status With Onset at Least 14 Days After Double-blind Vaccination on Day 1 (Day 15): Double-blind PhaseAge: Greater than or equal to (>=) 60 years220 Participants
Primary

Number of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind Phase

Molecularly confirmed moderate to severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>=20 breaths per minute and symptoms such as shortness of breath or two signs or symptoms such as heart rate \>= 90 beats/minute and symptoms such as cough from a list of signs and symptoms and severe/critical included one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute, SpO2 less than or equal to (\<=) 93 percent (%) on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the Intensive Care Unit (ICU), death defined as per Food and Drug Administration (FDA) guidance.

Time frame: From 28 days after double-blind vaccination on Day 1 (Day 29) up to Month 6

Population: PP set included participants of the Full Analysis Set (FAS) who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 28 in PP set were excluded.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind PhaseAge: 18-59 years340 Participants
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind PhaseAge: >=60 years93 Participants
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind PhaseAll participants433 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind PhaseAge: 18-59 years716 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind PhaseAge: >=60 years167 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind PhaseAll participants883 Participants
Primary

Number of Participants With Solicited Local Adverse Events (AEs) Up to 7 Days After Booster Vaccination (Open-label Booster Vaccination Phase)

Participants who received the booster dose were asked to note in the e-Diary occurrences of injection site pain/tenderness, erythema, and swelling at the study vaccine injection site daily for 7 days post-booster vaccination (day of vaccination and the subsequent 7 days).

Time frame: Up to Day 372 (7 Days after booster vaccination on Day 365 [Year 1])

Population: Full analysis booster set included all randomized participants with a documented study vaccine administration, regardless of the occurrence of protocol deviations and serostatus at enrollment, who received the Ad26.COV2.S booster vaccination at the booster visit.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Solicited Local Adverse Events (AEs) Up to 7 Days After Booster Vaccination (Open-label Booster Vaccination Phase)3758 Participants
Double-blind Phase: PlaceboNumber of Participants With Solicited Local Adverse Events (AEs) Up to 7 Days After Booster Vaccination (Open-label Booster Vaccination Phase)135 Participants
OL Phase: Non-mRNA Any Schedule +Ad26.COV2.S vp Booster OR mRNA Other Schedule +Ad26.COV2.S BoosterNumber of Participants With Solicited Local Adverse Events (AEs) Up to 7 Days After Booster Vaccination (Open-label Booster Vaccination Phase)204 Participants
Primary

Number of Participants With Solicited Systemic AEs Up to 7 Days After Booster Vaccination (Open-label Booster Vaccination Phase)

Participants recorded the temperature in the e-Diary in the evening of the day of vaccination, and then daily for the next 7 days approximately at the same time each day. If more than 1 measurement was made on any given day, the highest temperature of that day was recorded in the e-Diary. Fever was defined as endogenous elevation of body temperature \>= 38.0 degree Celsius or \>=100.4-degree Fahrenheit, as recorded in at least 1 measurement. Participants also noted the signs and symptoms in the e-Diary on a daily basis for 7 days post-booster vaccination (day of vaccination and the subsequent 7 days), if feasible, for the following events: fatigue, headache, nausea, myalgia.

Time frame: Up to Day 372 (7 Days after booster vaccination on Day 365 [Year 1])

Population: Full analysis booster set included all randomized participants with a documented study vaccine administration, regardless of the occurrence of protocol deviations and serostatus at enrollment, who received the Ad26.COV2.S booster vaccination at the booster visit.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Solicited Systemic AEs Up to 7 Days After Booster Vaccination (Open-label Booster Vaccination Phase)3559 Participants
Double-blind Phase: PlaceboNumber of Participants With Solicited Systemic AEs Up to 7 Days After Booster Vaccination (Open-label Booster Vaccination Phase)145 Participants
OL Phase: Non-mRNA Any Schedule +Ad26.COV2.S vp Booster OR mRNA Other Schedule +Ad26.COV2.S BoosterNumber of Participants With Solicited Systemic AEs Up to 7 Days After Booster Vaccination (Open-label Booster Vaccination Phase)198 Participants
Primary

Number of Participants With Unsolicited AEs Up to 28 Days After Booster Vaccination (Open-label Booster Vaccination Phase)

Unsolicited AEs were all AEs for which the participant is not specifically questioned in the participant diary.

Time frame: Up to Day 393 (28 Days after booster vaccination on Day 365 [Year 1])

Population: Full analysis booster set included all randomized participants with a documented study vaccine administration, regardless of the occurrence of protocol deviations and serostatus at enrollment, who received the Ad26.COV2.S booster vaccination at the booster visit.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Unsolicited AEs Up to 28 Days After Booster Vaccination (Open-label Booster Vaccination Phase)2133 Participants
Double-blind Phase: PlaceboNumber of Participants With Unsolicited AEs Up to 28 Days After Booster Vaccination (Open-label Booster Vaccination Phase)58 Participants
OL Phase: Non-mRNA Any Schedule +Ad26.COV2.S vp Booster OR mRNA Other Schedule +Ad26.COV2.S BoosterNumber of Participants With Unsolicited AEs Up to 28 Days After Booster Vaccination (Open-label Booster Vaccination Phase)95 Participants
Secondary

Area Under the Curve (AUC) of SARS-CoV-2 Viral Load as Assessed by Quantitative Reverse-Transcriptase Polymerase Chain Reaction (RT-PCR) in Participants With Molecularly Confirmed, Moderate to Severe/Critical COVID-19 (Double Blind Phase)

AUC of SARS-CoV-2 Viral Load was assessed in confirmed COVID-19 cases using RT-PCR. Nasal swabs were used to detect and/or quantify SARS-CoV-2.

Time frame: From Day 15 to end of the COVID-19 episode (Day 189)

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 14 in PP set were excluded. Here N (Overall number of participants analyzed) signifies participants evaluable for this OM.

ArmMeasureValue (MEAN)Dispersion
Double-blind Phase: Ad26.COV2.S 5*10^10 vpArea Under the Curve (AUC) of SARS-CoV-2 Viral Load as Assessed by Quantitative Reverse-Transcriptase Polymerase Chain Reaction (RT-PCR) in Participants With Molecularly Confirmed, Moderate to Severe/Critical COVID-19 (Double Blind Phase)823.7 Log10 copies*day per milliliterStandard Error 33.668
Double-blind Phase: PlaceboArea Under the Curve (AUC) of SARS-CoV-2 Viral Load as Assessed by Quantitative Reverse-Transcriptase Polymerase Chain Reaction (RT-PCR) in Participants With Molecularly Confirmed, Moderate to Severe/Critical COVID-19 (Double Blind Phase)921.47 Log10 copies*day per milliliterStandard Error 25.706
Secondary

Binding Antibodies to SARS-CoV-2 S Protein Assessed by ELISA (Double Blind Phase)

Binding antibodies to SARS-CoV-2 S protein as assessed by enzyme-linked immunosorbent assay (ELISA) to measure humoral immune response was reported. The lower limit of quantification (LLOQ) and upper limit of quantification (ULOQ) were 50.3 EU/mL and 58,158.10 EU/mL, respectively. A sample was considered positive if the value was strictly greater than the LLOQ (\>LLOQ).

Time frame: Baseline (Day 1), Day 29, and Day 71

Population: PPI set included all randomized and vaccinated participants, including those who were part of the immunogenicity subset and for whom immunogenicity data were available, excluding participants with major protocol deviations expected to impact the immunogenicity outcomes. Here N (Overall number of participants analyzed) signifies participants evaluated for this outcome measure and 'n' (number analyzed) signifies number of participants evaluable at specified time points.

ArmMeasureGroupValue (GEOMETRIC_MEAN)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpBinding Antibodies to SARS-CoV-2 S Protein Assessed by ELISA (Double Blind Phase)Baseline (Day 1)NA ELISA units per milliliter (EU/mL)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpBinding Antibodies to SARS-CoV-2 S Protein Assessed by ELISA (Double Blind Phase)Day 29336 ELISA units per milliliter (EU/mL)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpBinding Antibodies to SARS-CoV-2 S Protein Assessed by ELISA (Double Blind Phase)Day 71526 ELISA units per milliliter (EU/mL)
Double-blind Phase: PlaceboBinding Antibodies to SARS-CoV-2 S Protein Assessed by ELISA (Double Blind Phase)Baseline (Day 1)NA ELISA units per milliliter (EU/mL)
Double-blind Phase: PlaceboBinding Antibodies to SARS-CoV-2 S Protein Assessed by ELISA (Double Blind Phase)Day 29NA ELISA units per milliliter (EU/mL)
Double-blind Phase: PlaceboBinding Antibodies to SARS-CoV-2 S Protein Assessed by ELISA (Double Blind Phase)Day 71NA ELISA units per milliliter (EU/mL)
Secondary

Number of Participants With Adverse Events of Special Interest (AESI) (Double Blind Phase)

Number of participants with AESIs were reported. AESIs are significant AEs that are judged to be of special interest because of clinical importance, known or suspected class effects, or based on nonclinical signals. Thrombosis with Thrombocytopenia Syndrome (TTS), a syndrome characterized by a combination of both a thrombotic event and thrombocytopenia, is considered to be an AESI in this study. A suspected TTS case is defined as: Thrombotic events: suspected deep vessel venous or arterial thrombotic events; Thrombocytopenia, defined as platelet count below 150,000/micro liter.

Time frame: Baseline (Day 1) up to 35 weeks

Population: FAS included all randomized participants with a documented double-blind study vaccine administration, regardless of the occurrence of protocol deviations and serostatus at enrollment. Here N (Overall number of participants analyzed) signifies participants evaluated for this outcome measure (OM).

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Adverse Events of Special Interest (AESI) (Double Blind Phase)6 Participants
Double-blind Phase: PlaceboNumber of Participants With Adverse Events of Special Interest (AESI) (Double Blind Phase)5 Participants
Secondary

Number of Participants With Antibody Titers to Ad26.COV2.S (Booster Phase)

Number of participants with antibody titers to Ad26.COV2.S to measure immune response were reported.

Time frame: 28 days after booster vaccination on Day 365 (up to Day 393)

Population: PPI booster analysis set included all participants who received an Ad26.COV2.S booster dose (Year 1(Week 52)/Booster Visit) and who had been selected for inclusion in homologous or heterologous booster subset as of protocol amendment 6. This OM was planned to be analyzed based on homologous and heterologous booster groups. Here, 0 participants in overall number of participants analyzed field indicated that data for this OM was not collected and analyzed due to change in planned analysis.

Secondary

Number of Participants With Asymptomatic Infection Detected by RT-PCR at the Time of the Month 6/Unblinding Visit (Double Blind Phase)

Number of participants with asymptomatic infection detected by RT-PCR at the time of the Month 6/unblinding visit were reported.

Time frame: Month 6

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Asymptomatic Infection Detected by RT-PCR at the Time of the Month 6/Unblinding Visit (Double Blind Phase)10 Participants
Double-blind Phase: PlaceboNumber of Participants With Asymptomatic Infection Detected by RT-PCR at the Time of the Month 6/Unblinding Visit (Double Blind Phase)12 Participants
Secondary

Number of Participants With Binding Antibodies to SARS- CoV-2S Protein as Measured by ELISA (Booster Phase)

Number of participants with binding antibodies to SARS- CoV-2S protein as measured by ELISA was reported.

Time frame: 29 days after booster vaccination on Day 365 (Day 394)

Population: Per protocol booster immunogenicity analysis set included all participants who received an Ad26.COV2.S booster dose (Year 1 \[Week 52\]/Booster Visit) and who had been selected for inclusion in the homologous or heterologous booster subset as of protocol amendment 6. Here, 'N' (number of participants analyzed) signifies participants evaluable for this outcome measure. As planned, this outcome measure was analyzed based on homologous and heterologous booster groups.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Binding Antibodies to SARS- CoV-2S Protein as Measured by ELISA (Booster Phase)64 Participants
Double-blind Phase: PlaceboNumber of Participants With Binding Antibodies to SARS- CoV-2S Protein as Measured by ELISA (Booster Phase)26 Participants
OL Phase: Non-mRNA Any Schedule +Ad26.COV2.S vp Booster OR mRNA Other Schedule +Ad26.COV2.S BoosterNumber of Participants With Binding Antibodies to SARS- CoV-2S Protein as Measured by ELISA (Booster Phase)9 Participants
Heterologous Booster Group: Inactivated Vaccine + Ad26.COV2.S 5*10^10 vpNumber of Participants With Binding Antibodies to SARS- CoV-2S Protein as Measured by ELISA (Booster Phase)3 Participants
Secondary

Number of Participants With BOD Based on First Occurrence of Molecularly Confirmed Symptomatic COVID-19 (Double Blind Phase)

BOD is a weighted version of the mild, moderate, and severe/critical vaccine efficacies and was evaluated based on the first occurrence of molecularly confirmed COVID-19, including mild, moderate or severe/critical COVID-19 case.

Time frame: 28 Days after double-blind vaccination on Day 1 (Day 29)

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 28 in PP set were excluded.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With BOD Based on First Occurrence of Molecularly Confirmed Symptomatic COVID-19 (Double Blind Phase)443 Participants
Double-blind Phase: PlaceboNumber of Participants With BOD Based on First Occurrence of Molecularly Confirmed Symptomatic COVID-19 (Double Blind Phase)895 Participants
Secondary

Number of Participants With Burden of Disease (BOD) Based on First Occurrence of Molecularly Confirmed Symptomatic COVID-19 (Double Blind Phase)

BOD is a weighted version of the mild, moderate, and severe/critical vaccine efficacies and was evaluated based on the first occurrence of molecularly confirmed COVID-19, including mild, moderate or severe/critical COVID-19 case.

Time frame: 14 Days after double-blind vaccination on Day 1 (Day 15)

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 14 in PP set were excluded.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Burden of Disease (BOD) Based on First Occurrence of Molecularly Confirmed Symptomatic COVID-19 (Double Blind Phase)495 Participants
Double-blind Phase: PlaceboNumber of Participants With Burden of Disease (BOD) Based on First Occurrence of Molecularly Confirmed Symptomatic COVID-19 (Double Blind Phase)1082 Participants
Secondary

Number of Participants With First Occurrence of COVID-19 Requiring Medical Intervention (Double Blind Phase)

Number of participants with first occurrence of COVID-19 requiring medical intervention (such as a composite endpoint of hospitalization, ICU admission, mechanical ventilation, and ECMO, linked to objective measures such as decreased oxygenation, X-ray or CT findings) or linked to any molecularly confirmed, COVID-19 at least 28 days post vaccination were reported.

Time frame: 28 Days after double-blind vaccination on Day 1 (Day 29)

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 28 in PP set were excluded.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of COVID-19 Requiring Medical Intervention (Double Blind Phase)16 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of COVID-19 Requiring Medical Intervention (Double Blind Phase)64 Participants
Secondary

Number of Participants With First Occurrence of COVID-19 Requiring Medical Intervention (Double Blind Phase)

Number of participants with first occurrence of COVID-19 requiring medical intervention (such as a composite endpoint of hospitalization, ICU admission, mechanical ventilation, and extracorporeal membrane oxygenation \[ECMO\], linked to objective measures such as decreased oxygenation, X-ray or computed tomography \[CT\] findings) or linked to any molecularly confirmed, COVID-19 at least 14 days post vaccination were reported.

Time frame: 14 days after double-blind vaccination on Day 1 (Day 15)

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 14 in PP set were excluded.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of COVID-19 Requiring Medical Intervention (Double Blind Phase)18 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of COVID-19 Requiring Medical Intervention (Double Blind Phase)74 Participants
Secondary

Number of Participants With First Occurrence of Molecularly Confirmed COVID-19 Defined by the US Food and Drug Administration (FDA) Harmonized Case Definition (Double Blind Phase)

Molecularly confirmed COVID-19 was defined as a positive SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample; and COVID-19 symptoms consistent with those defined by the US FDA harmonized case definition at the time of finalization of the study protocol: fever or chills, cough, shortness of breath or difficulty breathing, fatigue, muscle or body aches, headache, new loss of taste or smell, sore throat, congestion or runny nose, nausea or vomiting, diarrhea.

Time frame: 14 Days after double-blind vaccination on Day 1 (Day 15)

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 14 in PP set were excluded.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed COVID-19 Defined by the US Food and Drug Administration (FDA) Harmonized Case Definition (Double Blind Phase)492 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed COVID-19 Defined by the US Food and Drug Administration (FDA) Harmonized Case Definition (Double Blind Phase)1067 Participants
Secondary

Number of Participants With First Occurrence of Molecularly Confirmed COVID-19 Defined by the US Food and Drug Administration (FDA) Harmonized Case Definition (Double Blind Phase)

Molecularly confirmed COVID-19 was defined as a positive SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample; and COVID-19 symptoms consistent with those defined by the US FDA harmonized case definition at the time of finalization of the study protocol: fever or chills, cough, shortness of breath or difficulty breathing, fatigue, muscle or body aches, headache, new loss of taste or smell, sore throat, congestion or runny nose, nausea or vomiting, diarrhea.

Time frame: 28 Days after double-blind vaccination on Day 1 (Day 29)

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 28 in PP set were excluded.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed COVID-19 Defined by the US Food and Drug Administration (FDA) Harmonized Case Definition (Double Blind Phase)441 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed COVID-19 Defined by the US Food and Drug Administration (FDA) Harmonized Case Definition (Double Blind Phase)884 Participants
Secondary

Number of Participants With First Occurrence of Molecularly Confirmed Mild COVID-19 (Double Blind Phase

Molecularly confirmed mild Covid-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample and one of the following signs and symptoms: fever (\>=38°C or \>=100.4°F), sore throat, malaise (loss of appetite, generally unwell, fatigue, physical weakness), headache, muscle pain (myalgia), gastrointestinal symptoms, cough, chest congestion, runny nose, wheezing, skin rash, eye irritation or discharge, chills, new or changing olfactory or taste disorders, red or bruised looking feet or toes, or shaking chills or rigors.

Time frame: 14 Days after double-blind vaccination on Day1 (Day 15)

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 14 in PP set were excluded.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Mild COVID-19 (Double Blind Phase11 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Mild COVID-19 (Double Blind Phase15 Participants
Secondary

Number of Participants With First Occurrence of Molecularly Confirmed Mild COVID-19 (Double Blind Phase)

Molecularly confirmed mild Covid-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample and one of the following signs and symptoms: fever (\>=38°C or \>=100.4°F), sore throat, malaise (loss of appetite, generally unwell, fatigue, physical weakness), headache, muscle pain (myalgia), gastrointestinal symptoms, cough, chest congestion, runny nose, wheezing, skin rash, eye irritation or discharge, chills, new or changing olfactory or taste disorders, red or bruised looking feet or toes, or shaking chills or rigors.

Time frame: 28 Days after double-blind vaccination on Day 1 (Day 29)

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 28 in PP set were excluded.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Mild COVID-19 (Double Blind Phase)10 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Mild COVID-19 (Double Blind Phase)12 Participants
Secondary

Number of Participants With First Occurrence of Molecularly Confirmed, Moderate to Severe/Critical COVID-19 for Seronegative Participants (Double Blind Phase)

Molecularly confirmed moderate to severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>= 20 breaths per minute and symptoms such as shortness of breath or two signs or symptoms such as heart rate \>= 90 beats per minute (beats/minute) and symptoms such as cough from a list of signs and symptoms and severe/critical included one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute,SpO2 \<=93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance. Seronegative is defined as N-serology seronegative at the time of boosting or at the Year 1 visit if not boosted.

Time frame: 1 day after double-blind vaccination on Day 1 (Day 2)

Population: FAS included all randomized participants with a documented double-blind study vaccine administration, regardless of the occurrence of protocol deviations and serostatus at enrollment.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed, Moderate to Severe/Critical COVID-19 for Seronegative Participants (Double Blind Phase)575 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed, Moderate to Severe/Critical COVID-19 for Seronegative Participants (Double Blind Phase)1189 Participants
Secondary

Number of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 Regardless of Their Serostatus (Double Blind Phase)

Molecularly confirmed moderate to severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>= 20 breaths per minute and symptoms such as shortness of breath or two signs or symptoms such as heart rate \>= 90 beats per minute (beats/minute) and symptoms such as cough from a list of signs and symptoms and severe/critical included one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute,SpO2 \<=93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance.

Time frame: 14 days after double-blind vaccination on Day 1 (Day 15)

Population: PP set included participants of the FAS who received double-blind study vaccine, regardless of their serostatus at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. This excludes participants who had a COVID-19 case with an onset before Day 15.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 Regardless of Their Serostatus (Double Blind Phase)487 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 Regardless of Their Serostatus (Double Blind Phase)1079 Participants
Secondary

Number of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 Regardless of Their Serostatus (Double Blind Phase)

Molecularly confirmed moderate to severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>= 20 breaths per minute and symptoms such as shortness of breath or two signs or symptoms such as heart rate \>= 90 beats per minute (beats/minute) and symptoms such as cough from a list of signs and symptoms and severe/critical included one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute,SpO2 \<=93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance.

Time frame: 28 days after double-blind vaccination on Day 1 (Day 29)

Population: PP set included participants of the FAS who received double-blind study vaccine, regardless of their serostatus at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. This excludes participants who had a COVID-19 case with an onset before Day 29.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 Regardless of Their Serostatus (Double Blind Phase)436 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 Regardless of Their Serostatus (Double Blind Phase)895 Participants
Secondary

Number of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 Regardless of Their Serostatus (Double Blind Phase)

Molecularly confirmed moderate to severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>= 20 breaths per minute and symptoms such as shortness of breath or two signs or symptoms such as heart rate \>= 90 beats per minute (beats/minute) and symptoms such as cough from a list of signs and symptoms and severe/critical included one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute,SpO2 \<=93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance.

Time frame: 1 day after double-blind vaccination on Day 1 (Day 2)

Population: FAS included all randomized participants with a documented double-blind study vaccine administration, regardless of the occurrence of protocol deviations and serostatus at enrollment.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 Regardless of Their Serostatus (Double Blind Phase)575 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Moderate to Severe/Critical COVID-19 Regardless of Their Serostatus (Double Blind Phase)1189 Participants
Secondary

Number of Participants With First Occurrence of Molecularly Confirmed Severe/Critical COVID-19 With Seronegative Status With Onset at Least 14 Days After Double-blind Vaccination on Day 1 (Day 15): Double-blind Phase

Molecularly confirmed severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample and one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute,SpO2 \<=93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance. Seronegative is defined as N-serology seronegative at the time of boosting or at the Year 1 visit if not boosted.

Time frame: From 14 days after double-blind vaccination on Day 1 (Day 15) up to Month 6

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 14 in PP set were excluded.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Severe/Critical COVID-19 With Seronegative Status With Onset at Least 14 Days After Double-blind Vaccination on Day 1 (Day 15): Double-blind Phase56 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Severe/Critical COVID-19 With Seronegative Status With Onset at Least 14 Days After Double-blind Vaccination on Day 1 (Day 15): Double-blind Phase205 Participants
Secondary

Number of Participants With First Occurrence of Molecularly Confirmed Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind Phase

Severe/critical COVID-19 was defined as a SARS-CoV-2 positive RT-PCR or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample and one of the following signs and symptoms: respiratory rate \>=30 breaths/minute, heart rate \>=125 beats/minute,SpO2 \<=93% on room air at sea level respiratory failure, evidence of shock, significant acute renal, hepatic, or neurologic dysfunction, admission to the ICU, death defined as per FDA guidance.

Time frame: From 28 days after double-blind vaccination on Day 1 (Day 29) up to Month 6

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a positive PCR test between Day 1 and Day 28 in PP set were excluded. Here, N (Overall number of participants analyzed) signifies participants evaluable for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of Molecularly Confirmed Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind Phase46 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of Molecularly Confirmed Severe/Critical COVID-19 With Seronegative Status With Onset at Least 28 Days After Double-blind Vaccination on Day 1 (Day 29): Double-blind Phase176 Participants
Secondary

Number of Participants With First Occurrence of SARS-CoV-2 Infection (Serologically and/or Molecularly Confirmed) (Double Blind Phase)

Number of participants with first occurrence of SARS-CoV-2 infection (serologically and/or molecularly confirmed) were reported.

Time frame: 28 days after double-blind vaccination on Day 1 (Day 29)

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Here N signifies the excluded participants who had a COVID-19 case with an onset or discontinued before Day 29.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With First Occurrence of SARS-CoV-2 Infection (Serologically and/or Molecularly Confirmed) (Double Blind Phase)1038 Participants
Double-blind Phase: PlaceboNumber of Participants With First Occurrence of SARS-CoV-2 Infection (Serologically and/or Molecularly Confirmed) (Double Blind Phase)1699 Participants
Secondary

Number of Participants With MAAEs Leading to Study Discontinuation (Double Blind Phase)

MAAEs were defined as AEs with medically-attended visits including hospital, emergency room, urgent care clinic, or other visits to or from medical personnel for any reason. Routine study visits were not considered medically-attended visits. New onset of chronic diseases was collected as part of the MAAEs.

Time frame: Up to 35 weeks

Population: FAS included all randomized participants with a documented double-blind study vaccine administration, regardless of the occurrence of protocol deviations and serostatus at enrollment. Here N (Overall number of participants analyzed) signifies participants evaluated for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With MAAEs Leading to Study Discontinuation (Double Blind Phase)1 Participants
Double-blind Phase: PlaceboNumber of Participants With MAAEs Leading to Study Discontinuation (Double Blind Phase)2 Participants
Secondary

Number of Participants With Medically-Attended Adverse Events (MAAEs) (Double Blind Phase)

An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. MAAEs were defined as AEs with medically-attended visits including hospital, emergency room, urgent care clinic, or other visits to or from medical personnel for any reason.

Time frame: Up to 6 months after double-blind vaccination on Day 1 (up to 6 months)

Population: FAS included all randomized participants with a documented double-blind study vaccine administration, regardless of the occurrence of protocol deviations and serostatus at enrollment. Here N (Overall number of participants analyzed) signifies participants evaluated for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Medically-Attended Adverse Events (MAAEs) (Double Blind Phase)1672 Participants
Double-blind Phase: PlaceboNumber of Participants With Medically-Attended Adverse Events (MAAEs) (Double Blind Phase)1885 Participants
Secondary

Number of Participants With SARS-CoV-2 Seroconversion Based on Antibodies to N Protein Using ELISA and/or SARS-CoV-2 Immunoglobulin Assay (Double Blind Phase)

Number of participants with SARS-CoV-2 seroconversion based on antibodies to nucleocapsid (N) protein using enzyme-linked immunosorbent assay (ELISA) and/or SARS-CoV- 2 immunoglobulin assay that is dependent on the SARS-CoV-2 N protein was reported.

Time frame: From Day 29 until end of double-blind phase at Month 6

Population: PP set included participants of the FAS who received double-blind study vaccine and who were seronegative at the time of double-blind vaccination and who had no other major protocol deviations that were judged to possibly impact the efficacy of the vaccine. Participants who had a COVID-19 case with an onset or discontinued before day 29 in PP set were excluded.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With SARS-CoV-2 Seroconversion Based on Antibodies to N Protein Using ELISA and/or SARS-CoV-2 Immunoglobulin Assay (Double Blind Phase)550 Participants
Double-blind Phase: PlaceboNumber of Participants With SARS-CoV-2 Seroconversion Based on Antibodies to N Protein Using ELISA and/or SARS-CoV-2 Immunoglobulin Assay (Double Blind Phase)724 Participants
Secondary

Number of Participants With Serious Adverse Events (SAEs) (Double Blind Phase)

An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. SAE is any untoward medical occurrence that at any dose may result in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, is a suspected transmission of any infectious agent via a medicinal product.

Time frame: Baseline (Day 1) up to 35 weeks

Population: FAS included all randomized participants with a documented double-blind study vaccine administration, regardless of the occurrence of protocol deviations and serostatus at enrollment. Here N (Overall number of participants analyzed) signifies participants evaluated for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Serious Adverse Events (SAEs) (Double Blind Phase)235 Participants
Double-blind Phase: PlaceboNumber of Participants With Serious Adverse Events (SAEs) (Double Blind Phase)358 Participants
Secondary

Number of Participants With Solicited Local Adverse Events (AEs) During 7 Days Following Vaccination (Double Blind Phase)

An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Participants who were enrolled in safety subset were asked to note in the e-Diary occurrences of injection site pain/tenderness, erythema, and swelling at the study vaccine injection site daily for 7 days post-vaccination (day of vaccination and the subsequent 7 days).

Time frame: Up to Day 8 (7 Days after double-blind vaccination on Day 1)

Population: Safety population is a subset of FAS for the analysis of solicited local adverse event. Here N (Overall number of participants analyzed) signifies participants evaluated for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Solicited Local Adverse Events (AEs) During 7 Days Following Vaccination (Double Blind Phase)1839 Participants
Double-blind Phase: PlaceboNumber of Participants With Solicited Local Adverse Events (AEs) During 7 Days Following Vaccination (Double Blind Phase)684 Participants
Secondary

Number of Participants With Solicited Systemic AEs During 7 Days Following Vaccination (Double Blind Phase)

An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with pharmaceutical/biological agent under study. Participants who were enrolled in safety subset were instructed on how to record daily temperature using a thermometer provided for home use. Participants recorded the temperature in the e-Diary in the evening of the day of vaccination, and then daily for the next 7 days approximately at the same time each day. If more than 1 measurement was made on any given day, the highest temperature of that day was recorded in the e-Diary. Fever was defined as endogenous elevation of body temperature \>= 38.0 degree Celsius or \>=100.4-degree Fahrenheit, as recorded in at least 1 measurement. Participants also noted the signs and symptoms in the e-Diary on a daily basis for 7 days post vaccination (day of vaccination and the subsequent 7 days), for the following events: fatigue, headache, nausea, myalgia.

Time frame: Up to Day 8 (7 Days after double-blind vaccination on Day 1)

Population: Safety population is a subset of FAS for the analysis of solicited systemic adverse event. Here N (Overall number of participants analyzed) signifies participants evaluated for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Solicited Systemic AEs During 7 Days Following Vaccination (Double Blind Phase)2021 Participants
Double-blind Phase: PlaceboNumber of Participants With Solicited Systemic AEs During 7 Days Following Vaccination (Double Blind Phase)1307 Participants
Secondary

Number of Participants With Unsolicited AEs During 28 Days Post-vaccination (Double Blind Phase)

An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Unsolicited AEs were all AEs for which the participant is not specifically questioned in the participant diary.

Time frame: Up to Day 29 (28 Days after double-blind vaccination on Day 1)

Population: Safety population is a subset of FAS for the analysis of unsolicited adverse event. Here N (Overall number of participants analyzed) signifies participants evaluated for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Double-blind Phase: Ad26.COV2.S 5*10^10 vpNumber of Participants With Unsolicited AEs During 28 Days Post-vaccination (Double Blind Phase)456 Participants
Double-blind Phase: PlaceboNumber of Participants With Unsolicited AEs During 28 Days Post-vaccination (Double Blind Phase)422 Participants

Source: ClinicalTrials.gov · Data processed: Feb 24, 2026