Trial Outcomes & Findings for A Study of an Adenovirus Serotype 26 Pre-fusion Conformation-stabilized F Protein (Ad26. RSV. preF) Based Respiratory Syncytial Virus (RSV) Vaccine in the Prevention of Lower Respiratory Tract Disease in Adults Aged 60 Years and Older (NCT NCT04908683)

Last Updated: 2025-11-13

Results Overview

Number of participants with first occurrence of RT-PCR-confirmed RSV mediated LRTD according to protocol defined criteria were reported. A participant was considered to have RT-PCR-confirmed RSV-mediated LRTD if the following criteria were met: new onset or worsening from baseline of 3 or more of the symptoms as captured on the respiratory infection intensity and impact questionnaire (RiiQ, version 2) at the same assessment time point: cough, short of breath, coughing up phlegm (sputum), and wheezing and confirmation of RSV by RT-PCR in one or more of the nasal swabs, or in the sputum sample. RiiQ symptom scale was a 13-item questionnaire rated on a 4-point scale. Each symptom was rated on a scale of 0 to 3 where 0=None, 1=Mild, 2=Moderate, and 3=Severe. Higher scores indicated greater severity. The total LRTD symptom score was calculated as the mean of the 4 lower respiratory scores (cough, short of breath, coughing up phlegm \[sputum\] and wheezing).

Recruitment status

COMPLETED

Study phase

PHASE3

Target enrollment

25236 participants

Primary outcome timeframe

From Baseline (Day 1) up to 12 months

Results posted on

2025-11-13

Participant Flow

Participant milestones

Participant milestones
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo Participants received a single IM injection of matching placebo on Day 1.
Overall Study STARTED	16817	8419
Overall Study Randomized and Vaccinated	16709	8367
Overall Study COMPLETED	124	59
Overall Study NOT COMPLETED	16693	8360

Reasons for withdrawal

Reasons for withdrawal
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo Participants received a single IM injection of matching placebo on Day 1.
Overall Study Failure to meet continuation criteria	34	22
Overall Study Initiated prohibited medication	3	0
Overall Study Randomized by mistake	1	0
Overall Study Lost to Follow-up	679	341
Overall Study Participant met eligibility criteria but were not needed	3	1
Overall Study Physician Decision	44	35
Overall Study Technical problems	12	9
Overall Study Withdrawal by legally authorized representative	1	0
Overall Study Protocol Violation	2	0
Overall Study Withdrawal by Subject	1188	570
Overall Study Site Closure by Sponsor	6	3
Overall Study Adverse Event	21	11
Overall Study Death	101	61
Overall Study Sponsor's decision	14398	7205
Overall Study Other	92	50
Overall Study Randomized not vaccinated	108	52

Baseline Characteristics

A Study of an Adenovirus Serotype 26 Pre-fusion Conformation-stabilized F Protein (Ad26. RSV. preF) Based Respiratory Syncytial Virus (RSV) Vaccine in the Prevention of Lower Respiratory Tract Disease in Adults Aged 60 Years and Older

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=16709 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=8367 Participants Participants received a single IM injection of matching placebo on Day 1.	Total n=25076 Participants Total of all reporting groups
Race (NIH/OMB) American Indian or Alaska Native	58 Participants n=10 Participants	17 Participants n=10 Participants	75 Participants n=20 Participants
Age, Continuous	70.2 years STANDARD_DEVIATION 5.24 • n=10 Participants	70.2 years STANDARD_DEVIATION 5.23 • n=10 Participants	70.2 years STANDARD_DEVIATION 5.24 • n=20 Participants
Age, Customized Adults (60-64 years)	1472 Participants n=10 Participants	740 Participants n=10 Participants	2212 Participants n=20 Participants
Age, Customized From 65 to 84 years	15053 Participants n=10 Participants	7534 Participants n=10 Participants	22587 Participants n=20 Participants
Age, Customized 85 years and over	184 Participants n=10 Participants	93 Participants n=10 Participants	277 Participants n=20 Participants
Sex/Gender, Customized Female	9063 Participants n=10 Participants	4452 Participants n=10 Participants	13515 Participants n=20 Participants
Sex/Gender, Customized Male	7645 Participants n=10 Participants	3913 Participants n=10 Participants	11558 Participants n=20 Participants
Sex/Gender, Customized Others	1 Participants n=10 Participants	2 Participants n=10 Participants	3 Participants n=20 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	1555 Participants n=10 Participants	741 Participants n=10 Participants	2296 Participants n=20 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	14903 Participants n=10 Participants	7496 Participants n=10 Participants	22399 Participants n=20 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	251 Participants n=10 Participants	130 Participants n=10 Participants	381 Participants n=20 Participants
Race (NIH/OMB) Asian	1757 Participants n=10 Participants	897 Participants n=10 Participants	2654 Participants n=20 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	98 Participants n=10 Participants	49 Participants n=10 Participants	147 Participants n=20 Participants
Race (NIH/OMB) Black or African American	1820 Participants n=10 Participants	935 Participants n=10 Participants	2755 Participants n=20 Participants
Race (NIH/OMB) White	12649 Participants n=10 Participants	6297 Participants n=10 Participants	18946 Participants n=20 Participants
Race (NIH/OMB) More than one race	189 Participants n=10 Participants	101 Participants n=10 Participants	290 Participants n=20 Participants
Race (NIH/OMB) Unknown or Not Reported	138 Participants n=10 Participants	71 Participants n=10 Participants	209 Participants n=20 Participants

PRIMARY outcome

Timeframe: From Baseline (Day 1) up to 12 months

Population: Per-protocol efficacy (PPE) population included all randomized and vaccinated participants, excluding those with major protocol deviations (MPDs) expecting to impact the efficacy outcomes. Participants with an RSV onset within 14 days after vaccination and participants who discontinued within 14 days after vaccination were excluded from the PPE population.

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=16263 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=8152 Participants Participants received a single IM injection of matching placebo on Day 1.
Number of Participants With First Occurrence of Reverse Transcriptase Polymerase Chain Reaction (RT-PCR)-Confirmed Respiratory Syncytial Virus (RSV) Mediated Lower Respiratory Tract Disease (LRTD)	44 Participants	63 Participants

SECONDARY outcome

Timeframe: From Baseline (Day 1) up to 12 months

Population: PPE population included all randomized and vaccinated participants, excluding those with MPDs expecting to impact the efficacy outcomes. Participants with an RSV onset within 14 days after vaccination and participants who discontinued within 14 days after vaccination were excluded from the PPE population.

A participant was considered to have RT-PCR-confirmed RSV-mediated ARI if the following protocol defined criteria were met: ARI episode initiated by the participant and confirmed by the site with symptoms consistent with an ARI (new symptoms or worsening from baseline of at least one of the symptoms as captured on the RiiQ): sore throat, nasal congestion, cough, short of breath, coughing up phlegm (sputum), wheezing and confirmation of RSV by RT-PCR in one or more of the nasal swabs, or in the sputum sample. RiiQ symptom scale was a 13-items questionnaire rated on a 4-point scale. Each symptom was rated on a scale of 0 to 3 where 0=None, 1=Mild, 2=Moderate, and 3=Severe. Higher scores indicated greater severity. The total ARI symptom score was calculated as the mean of the 4 lower respiratory scores (cough, short of breath, coughing up phlegm \[sputum\] and wheezing).

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=16263 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=8152 Participants Participants received a single IM injection of matching placebo on Day 1.
Number of Participants With First Occurrence of Any RT-PCR-Confirmed RSV-mediated Acute Respiratory Infection (ARI)	77 Participants	101 Participants

SECONDARY outcome

Timeframe: From Month 12 up to Month 24

Number of participants with first occurrence of any RT-PCR-confirmed RSV mediated LRTD during the second year were reported. A participant was considered to have RT-PCR-confirmed RSV-mediated LRTD if the following criteria were met: new onset or worsening from baseline of 3 or more of the symptoms as captured on the RiiQ, version 2 at the same assessment time point: cough, short of breath, coughing up phlegm (sputum), and wheezing and confirmation of RSV by RT-PCR in one or more of the nasal swabs, or in the sputum sample. RiiQ symptom scale was a 13-items questionnaire rated on a 4-point scale. Each symptom was rated on a scale of 0 to 3 where 0=None, 1=Mild, 2=Moderate, and 3=Severe. Higher scores indicated greater severity. The total LRTD symptom score was calculated as the mean of the 4 lower respiratory scores (cough, short of breath, coughing up phlegm \[sputum\] and wheezing).

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=10031 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=5011 Participants Participants received a single IM injection of matching placebo on Day 1.
Number of Participants With First Occurrence of RT-PCR-Confirmed RSV Mediated LRTD During the Second Year	16 Participants	29 Participants

SECONDARY outcome

Timeframe: From Month 12 up to Month 24

A participant was considered to have RT-PCR-confirmed RSV-mediated ARI according to protocol defined criteria were reported. A participant was considered to have RT-PCR-confirmed RSV-mediated ARI if the following criteria were met: ARI episode initiated by the participant and confirmed by the site with symptoms consistent with an ARI (new symptoms or worsening from baseline of at least one of the symptoms as captured on the RiiQ): sore throat, nasal congestion, cough, short of breath, coughing up phlegm (sputum), wheezing and confirmation of RSV by RT-PCR in one or more of the nasal swabs, or in the sputum sample. RiiQ symptom scale was a 13-items questionnaire rated on a 4-point scale. Each symptom was rated on a scale of 0 to 3 where 0=None, 1=Mild, 2=Moderate, and 3=Severe. Higher scores indicated greater severity. The total ARI symptom score was calculated as the mean of the 4 lower respiratory scores (cough, short of breath, coughing up phlegm \[sputum\] and wheezing).

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=10031 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=5011 Participants Participants received a single IM injection of matching placebo on Day 1.
Number of Participants With First Occurrence of Any RT-PCR-Confirmed RSV Mediated ARI During the Second Year	39 Participants	44 Participants

SECONDARY outcome

Timeframe: Baseline (Day 1) up to 24 months

Population: PPE population is defined as population included all randomized and vaccinated participants, excluding those with MPDs expecting to impact the efficacy outcomes. Participants with an RSV onset within 14 days after vaccination and participants who discontinued within 14 days after vaccination were excluded from the PPE population.

A participant was considered to have clinically relevant disease with specific parameters associated with an RT-PCR-confirmed RSV-mediated ARI if the following criteria were met: the participant had an RT-PCR-confirmed RSV-mediated ARI: ARI episode initiated by the participant and confirmed by the site with symptoms consistent with an ARI (new symptoms or worsening from baseline of at least one of the symptoms as captured on the RiiQ): sore throat, nasal congestion, cough, short of breath, coughing up phlegm (sputum), wheezing and confirmation of RSV by RT-PCR in one or more of the nasal swabs, or in the sputum sample; any of the following associated with ARI: hospitalization, emergency department visit, per clinical judgement of complications, decreased oxygen saturation, tachypnea, need of supplemental oxygen, hypotension, pulmonary function test and arterial blood gas result.

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=16263 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=8152 Participants Participants received a single IM injection of matching placebo on Day 1.
Number of Participants With First Occurrence of Predefined Clinically Relevant Disease Associated With RT-PCR-Confirmed RSV-Mediated ARI Over the Whole Study	4 Participants	11 Participants

SECONDARY outcome

Timeframe: 28 days post vaccination on Day 1 (Day 29); First year follow-up (from Day 29 up to 6 months, that is, up to Day 154)

Population: Full analysis set (FAS) included all participants with a documented vaccine administration, regardless of the occurrence of protocol deviations. Here, 'n' (number analyzed) represents number of participants who were evaluable for specified timepoints.

Number of participants with SAEs were reported. An adverse event (AE) is any untoward medical occurrence in a clinical study participant administered a pharmaceutical (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the intervention. An 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.

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=16709 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=8367 Participants Participants received a single IM injection of matching placebo on Day 1.
Number of Participants With Serious Adverse Events (SAEs) 28 days post vaccination on Day 1	119 Participants	53 Participants
Number of Participants With Serious Adverse Events (SAEs) First year follow-up	446 Participants	239 Participants

SECONDARY outcome

Timeframe: 28 days post vaccination on Day 1 (Day 29); First year follow-up (from Day 29 up to 6 months, that is, up to Day 154)

Population: FAS included all participants with a documented vaccine administration, regardless of the occurrence of protocol deviations. Here, 'n' (number analyzed) represents number of participants who were evaluable for specified timepoints.

Number of participants with potential AESIs were reported. AESIs were significant AEs that were judged to be of special interest because of clinical importance, known or suspected class effects, or based on nonclinical signals. AESIs were embolic and thrombotic events, hematopoietic thrombocytopenia, and cerebral hemorrhage.

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=16709 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=8367 Participants Participants received a single IM injection of matching placebo on Day 1.
Number of Participants With Potential Adverse Events of Special Interest (AESIs) 28 days post vaccination on Day 1	25 Participants	4 Participants
Number of Participants With Potential Adverse Events of Special Interest (AESIs) First year follow-up	71 Participants	35 Participants

SECONDARY outcome

Timeframe: Up to Day 7 post vaccination on Day 1 (up to Day 8)

Population: The safety subset included all participants that consented to the collection of AEs (solicited AEs for up to 7 days after vaccination). Here, 'N' (Overall number of participants analyzed) signifies participants who were evaluable for this outcome measure.

Number of participants with solicited local AEs 7 days post vaccination were reported. An AE was any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the intervention. Solicited local AEs were precisely defined events that participants were specifically asked about and which were noted by participants in the diary. Solicited local AEs included erythema, swelling, and pain/tenderness at the study vaccine injection site, were used to assess the reactogenicity of the study vaccine and were pre-defined local (injection site). All solicited AEs at the injection site (local) were considered related to the study vaccine administration.

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=2305 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=1155 Participants Participants received a single IM injection of matching placebo on Day 1.
Number of Participants With Solicited Local Adverse Events (AEs) up to 7 Days After Vaccination	1076 Participants	169 Participants

SECONDARY outcome

Timeframe: Up to Day 7 post vaccination on Day 1 (up to Day 8)

Population: The safety subset (a subset of FAS) included all participants that consented to the collection of AEs (solicited AEs for up to 7 days after vaccination). Here, 'N' (Overall number of participants analyzed) signifies participants who were evaluable for this outcome measure.

Number of participants with solicited systemic AEs 7 days post vaccination were reported. An AE was any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the intervention. Solicited systemic AEs included fatigue, headache, myalgia, nausea, pyrexia, for which participants were specifically questioned and which were noted by participants in their participant diary for 7 days post vaccination (day of vaccination and the subsequent 7 days).

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=2305 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=1155 Participants Participants received a single IM injection of matching placebo on Day 1.
Number of Participants With Solicited Systemic AEs up to 7 Days After Vaccination	1018 Participants	236 Participants

SECONDARY outcome

Timeframe: Up to 28 days post vaccination on Day 1 (up to Day 29)

Population: The safety subset (a subset of FAS) included all participants that consented to the collection of AEs (unsolicited AEs for 28 days after vaccination). Here, 'N' (Overall number of participants analyzed) signifies participants who were evaluable for this outcome measure.

Number of participants with unsolicited AEs 28 days post vaccination were reported. An AE was any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the intervention. Unsolicited adverse events included all adverse events for which the participant was not specifically questioned in the subject diary.

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=2330 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=1165 Participants Participants received a single IM injection of matching placebo on Day 1.
Number of Participants With Unsolicited AEs up to 28 Days After Vaccination	554 Participants	206 Participants

SECONDARY outcome

Timeframe: At 14 Days post vaccination on Day 1 (Day 15)

Population: Per-protocol Immunogenicity (PPI) population included all randomized and vaccinated participants who were part of the immunogenicity subset (consisted of at least 360 participants, of whom \~50% were at increased risk for severe RSV disease and \~50% were 75 years or older) and for whom immunogenicity data were available. Here, 'N' (Overall number of participants analyzed) signifies participants who were evaluable for this outcome measure.

RSV A2 strain neutralizing antibody titers of the vaccine-induced immune response was assessed through virus neutralization assay.

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=219 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=108 Participants Participants received a single IM injection of matching placebo on Day 1.
Respiratory Syncytial Virus (RSV) A2 Strain Neutralization Antibody Titers at 14 Days Post Vaccination	7194 Titers Interval 6394.0 to 8093.0	537 Titers Interval 455.0 to 634.0

SECONDARY outcome

Timeframe: At 14 days post vaccination on Day 1 (Day 15)

Population: PPI population included all randomized and vaccinated participants who were part of the immunogenicity subset and for whom immunogenicity data were available. Here, 'N' (Overall number of participants analyzed) signifies participants who were evaluable for this outcome measure.

GMTs of preF antibodies IgG at 14 days after the administration of Ad26.RSV.preF-based vaccine as assessed by ELISA were reported.

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=219 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=108 Participants Participants received a single IM injection of matching placebo on Day 1.
Geometric Mean Titers (GMTs) of Prefusion F-protein (Pre-F) Antibodies Immunoglobulin G (IgG) as Assessed by Enzyme-linked Immunosorbent Assay (ELISA) at 14 Days Post Vaccination	4932 Titers Interval 4477.0 to 5433.0	410 Titers Interval 348.0 to 484.0

SECONDARY outcome

Timeframe: 14 days post vaccination on Day 1 (Day 15)

Population: PPI population included all randomized and vaccinated participants who were part of the immuno subset and for whom immunogenicity data were available. Here, 'N' (Overall number of participants analyzed) signifies participants who were evaluable for this outcome measure.

T-cell IFN gamma responses to RSV F protein specific peptides at 14 days after vaccination as measured by ELISpot assay were reported. RSV F specific T-cell IFN gamma ELISpot responses were measured as counts of spot forming cells per million peripheral blood mononuclear cells (SFC/10\^6 PBMCs).

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=185 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=92 Participants Participants received a single IM injection of matching placebo on Day 1.
T-cell Interferon (IFN) Gamma Responses to Respiratory Syncytial Virus (RSV) F Protein Peptides Analyzed by Enzyme-linked Immunospot Assay (ELISpot)	533 SFC/10^6 PBMCs Interval 306.0 to 873.0	NA SFC/10^6 PBMCs Interval to 78.0 Median and lower limit of full range could not be estimated as it was below the lower limit of quantification (LLOQ: 68 SFC/10\^6 PBMCs ).

SECONDARY outcome

Timeframe: Baseline (Day 1) up to 24 months

Population: PPE population includes all randomized and vaccinated participants, excluding those with major protocol deviations (MPDs) expecting to impact the efficacy outcomes. Participants with an RSV onset within 14 days after vaccination and participants who discontinued within 14 days after vaccination were excluded from the PPE population. Here, 'N' (Overall number of participants analyzed) signifies participants who were evaluable for this outcome measure.

RiiQ symptom scale was a 13-items questionnaire rated on a 4-point scale. The respiratory symptoms included 2 upper respiratory tract infection (URTI) symptoms (nasal congestion and sore throat), 4 lower respiratory tract infection (LRTI) symptoms (cough, wheezing, short of breath, and coughing up phlegm/sputum) and 7 systemic symptoms (headache, feeling feverish, neck pain, body aches and pain, fatigue/tiredness, interrupted sleep, and loss of appetite). Each symptom was rated on a scale of 0 to 3 where 0=None, 1=Mild, 2=Moderate, and 3=Severe. Higher scores indicated greater severity. RiiQ total Symptom score was the mean of all scores (based on 13 symptoms). The AUC of the change from baseline for the RiiQ total symptom score and the RiiQ lower respiratory symptom score during the ARI was calculated.

Outcome measures

Outcome measures
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=115 Participants Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=143 Participants Participants received a single IM injection of matching placebo on Day 1.
Area Under the Curve (AUC) of the Change From Baseline in Respiratory Infection Intensity and Impact Questionnaire (RiiQ) Total Symptom Scale Score	82 Scores on a scale*hours Interval 21.0 to 141.0	107 Scores on a scale*hours Interval 48.0 to 218.0

Adverse Events

Group 1: Ad26.RSV.preF and RSV preF Protein

Serious events: 842 serious events

Other events: 1477 other events

Deaths: 105 deaths

Group 2: Placebo

Serious events: 457 serious events

Other events: 408 other events

Deaths: 61 deaths

Serious adverse events

Other adverse events

Other adverse events
Measure	Group 1: Ad26.RSV.preF and RSV preF Protein n=2330 participants at risk；n=16709 participants at risk Participants received a single intramuscular (IM) injection containing a mixture of adenovirus serotype 26 respiratory syncytial virus pre-fusion conformation stabilized F-protein (Ad26.RSV.preF) at a dose of 1\*10\^11 viral particles (vp) and RSV preF protein 150 micrograms (mcg) on Day 1.	Group 2: Placebo n=1165 participants at risk；n=8367 participants at risk Participants received a single IM injection of matching placebo on Day 1.
Gastrointestinal disorders Nausea(Solicited)	13.9% 324/2330 • Number of events 324 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	6.4% 75/1165 • Number of events 75 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
General disorders Fatigue(Solicited)	33.9% 789/2330 • Number of events 789 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	14.2% 165/1165 • Number of events 165 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
General disorders Pain	2.1% 48/2330 • Number of events 61 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	1.0% 12/1165 • Number of events 18 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
General disorders Pyrexia(Solicited)	7.3% 171/2330 • Number of events 171 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	0.43% 5/1165 • Number of events 5 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
General disorders Vaccination Site Erythema(Solicited)	2.7% 63/2330 • Number of events 63 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	0.43% 5/1165 • Number of events 5 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
General disorders Vaccination Site Pain(Solicited)	45.7% 1065/2330 • Number of events 1065 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	14.4% 168/1165 • Number of events 168 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
General disorders Vaccination Site Swelling(Solicited)	2.9% 68/2330 • Number of events 68 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	0.26% 3/1165 • Number of events 3 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
Investigations Blood Pressure Diastolic Increased	2.5% 58/2330 • Number of events 58 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	1.8% 21/1165 • Number of events 21 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
Investigations Blood Pressure Systolic Increased	6.4% 150/2330 • Number of events 150 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	5.2% 60/1165 • Number of events 60 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
Investigations Respiratory Rate Increased	3.8% 89/2330 • Number of events 89 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	4.2% 49/1165 • Number of events 49 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
Musculoskeletal and connective tissue disorders Myalgia(Solicited)	26.4% 614/2330 • Number of events 614 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	10.2% 119/1165 • Number of events 119 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
Nervous system disorders Headache(Solicited)	25.6% 597/2330 • Number of events 597 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	11.0% 128/1165 • Number of events 128 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).
Respiratory, thoracic and mediastinal disorders Cough	2.9% 68/2330 • Number of events 74 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).	2.1% 25/1165 • Number of events 26 • From Day 1 up to 24 months post-vaccination on Day 1 (Day 731). All-cause mortality and serious adverse events (SAEs) were analyzed on Full Analysis Set (FAS) population. Other (not including serious) AEs as solicited and unsolicited AEs were collected and analyzed on a subset of FAS that is called safety subset. The safety subset included all participants that consented to the collection of AEs (solicited and unsolicited AEs).

Additional Information

Clinical Franchise Leader

Janssen Vaccines & Prevention B.V.

Phone: 844-434-4210

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee If an investigator wishes to publish information from the study, a copy of the manuscript must be provided to the sponsor for review at least 60 days before submission for publication or presentation. If requested by the sponsor in writing, the investigator will withhold such publication for up to an additional 60 days.
Publication restrictions are in place

Restriction type: OTHER