Respiratory Syncytial Virus (RSV)Phase 3NCT07768345
A Study to Learn About Revaccination With a Vaccine Called RSVpreF in Immunocompromised Adults
A Phase 3 study testing RSVpreF Vaccine in people with Respiratory Syncytial Virus (RSV), run by Pfizer at 17 sites in United States.
Trial summary
The purpose of this phase 3 study is to learn the safety, tolerability and immunogenicity of revaccination with RSVpreF at approximately 1-, 2-, and 3-year intervals to inform the revaccination interval in immunocompromised adults. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Respiratory Syncytial Virus (RSV)
- What is being tested?
- RSVpreF Vaccine
- Type of treatment
- Vaccines
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 440 participants
- Where
- 17 sitesUnited States
- Study dates
- 31 Aug 2026to 2 Feb 2028
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Participants ≥18 years of age who are/were immunocompromised at the time of initial RSVpreF vaccination, per study protocol, and will be grouped based on prior RSV vaccination history:
- Group 1 will include participants naïve to any RSV vaccine.
- Group 2 will include participants who received a single prior dose of RSVpreF (Abrysvo) approximately 1 year (9 to 15 months) prior to enrollment.
- Group 3 will include participants who received a single prior dose of RSVpreF (Abrysvo) approximately 2 years (21 to 27 months) prior to enrollment.
- Group 4 will include participants who previously received 2 doses of RSVpreF in Study C3671023 Substudy B approximately 3 years (36 to 42 months) prior to enrollment.
- Participants should have a life expectancy ≥12 months (365 days) in the opinion of the investigator at enrollment.
Who cannot join
- Prior history of any subtype of Guillain-Barré Syndrome (GBS) of any etiology.
- History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis) to any components of the study intervention(s).
- Participants with a history of transplant rejection, or PTLD, or participants who have had treatment for these conditions, within 90 days prior to study enrollment or suspected chronic humoral or cellular rejection.
- Receipt of B-cell depleting therapies within 180 days prior to initial study vaccination.
- Refer to the study contact for further eligibility details.
Trial locations and contacts
17 sites in 1 country. Contact the study team or a site near you to ask about taking part.
17 sites in 1 country
United States17 sites, 17 recruiting
- Recruiting
University of Maryland, Institute of Human Virology
Baltimore, Maryland, 21201
- Recruiting
The Hope Clinic of Emory University
Decatur, Georgia, 30030
- Recruiting
Epic Medical Research-Desoto
DeSoto, Texas, 75115
- Recruiting
Altoona Center for Clinical Research
Duncansville, Pennsylvania, 16635
- Not yet recruiting
Duke Vaccine and Trials Unit
Durham, North Carolina, 27703
- Not yet recruiting
Duke Clinics 2F, 2G
Durham, North Carolina, 27710
- Recruiting
University of Iowa
Iowa City, Iowa, 52242
- Recruiting
University of Iowa, Infectious Disease Research Laboratory, VA Medical Center
Iowa City, Iowa, 52246
- Recruiting
Kaiser Foundation Hospital LAMC
Los Angeles, California, 90027
- Recruiting
Kaiser Permanente Los Angeles Medical center
Los Angeles, California, 90027
- Recruiting
Kaiser Permanente
Los Angeles, California, 90027
- Recruiting
NYU Langone Health Vaccine Center
New York, New York, 10016
- Recruiting
Rochester Clinical Research
Rochester, New York, 14609
- Not yet recruiting
University of Rochester Investigational Drug Services
Rochester, New York, 14642
- Not yet recruiting
University of Rochester Medical Center-Infectious Diseases Research Clinic
Rochester, New York, 14642
- Recruiting
Washington University School of Medicine
St Louis, Missouri, 63110
- Recruiting
George Washington University
Washington D.C., District of Columbia, 20037
About this study
Official title: A PHASE 3, OPEN-LABEL STUDY TO EVALUATE THE SAFETY, TOLERABILITY, AND IMMUNOGENICITY OF REVACCINATION WITH RESPIRATORY SYNCYTIAL VIRUS STABILIZED PREFUSION F SUBUNIT VACCINE (RSVPREF) IN IMMUNOCOMPROMISED ADULTS
The purpose of this phase 3 study is to learn the safety, tolerability and immunogenicity of revaccination with RSVpreF at approximately 1-, 2-, and 3-year intervals to inform the revaccination interval in immunocompromised adults.
This study is seeking participants who are 18 years of age and older and will be grouped based on prior RSV vaccination history. Participants are required to be immunocompromised per study protocol.
All participants in this study will receive 1 shot to their arm of a RSVPreF vaccine.
Participants will take part in this study for about 12 months and will need to visit the clinical study site at least 4 times.
- Conditions
- Respiratory Syncytial Virus (RSV)
- Being tested
- RSVpreF Vaccine
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
RSVpreF VaccineBiological
RSVpreF Vaccine
| Study group | Role | What they receive |
|---|---|---|
| Group 1 | Experimental | RSVpreF Vaccine Receives: Biological: RSVpreF Vaccine |
| Group 2 | Experimental | RSVpreF Vaccine Receives: Biological: RSVpreF Vaccine |
| Group 3 | Experimental | RSVpreF Vaccine Receives: Biological: RSVpreF Vaccine |
| Group 4 | Experimental | RSVpreF Vaccine Receives: Biological: RSVpreF Vaccine |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percentage of participants reporting local reactions
Measured: For up to 7 days after vaccination
Percentage of participants reporting systemic events
Measured: For up to 7 days after vaccination
Percentage of participants reporting adverse events
Measured: Through 1 month after vaccination
Percentage of participants reporting newly diagnosed chronic medical conditions
Measured: Through 12 months after vaccination
Percentage of participants reporting serious adverse events
Measured: Through 12 months after vaccination
Neutralizing Titers (NTs) for RSV A and RSV B expressed as Geometric Mean Titer (GMT)
Measured: Before vaccination, 1 month, 6 months and 12 months after vaccination
NTs for RSV A and RSV B expressed as Geometric Mean Fold Rise (GMFR)
Measured: Before vaccination, 1 month, 6 months and 12 months after vaccination
Secondary outcomes (1)
Seroresponse rate of NTs for RSV A and RSV B
Measured: 1 month after revaccination
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Aug 2026
- Study start31 Aug 2026
- Primary completion2 Feb 2028 (estimated)
- Study completion2 Feb 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Respiratory Syncytial Virus (RSV)Studies of the same condition, open and under way.
- More trials run by PfizerThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Prevention
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 440 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Pfizer
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Pfizer CT.gov Call Center, Study director, Pfizer
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07768345
- Sponsor's protocol ID
- C3671085
- Status last verified
- Oct 2026
- First submitted
- 12 Aug 2026
- Last updated
- 14 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.
Study at a glance
From the registry record, last updated by the sponsor on 14 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A PHASE 3, OPEN-LABEL STUDY TO EVALUATE THE SAFETY, TOLERABILITY, AND IMMUNOGENICITY OF REVACCINATION WITH RESPIRATORY SYNCYTIAL VIRUS STABILIZED PREFUSION F SUBUNIT VACCINE (RSVPREF) IN IMMUNOCOMPROMISED ADULTS
- ClinicalTrials.gov ID
- NCT07768345
- Acronym / sponsor ID
- C3671085
- Conditions
- Respiratory Syncytial Virus (RSV)
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 440 participants (estimated)
- Lead sponsor
- PfizerIndustry (pharma, biotech, devices)
- Study start
- 31 Aug 2026 (actual)
- Primary completion
- 2 Feb 2028 (estimated)
- Study completion
- 2 Feb 2028 (estimated)
- First posted
- 17 Aug 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this phase 3 study is to learn the safety, tolerability and immunogenicity of revaccination with RSVpreF at approximately 1-, 2-, and 3-year intervals to inform the revaccination interval in immunocompromised adults.
This study is seeking participants who are 18 years of age and older and will be grouped based on prior RSV vaccination history. Participants are required to be immunocompromised per study protocol.
All participants in this study will receive 1 shot to their arm of a RSVPreF vaccine.
Participants will take part in this study for about 12 months and will need to visit the clinical study site at least 4 times.
Study design
- Primary purpose
- Prevention
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Group 1 | Experimental | Biological: RSVpreF VaccineRSVpreF Vaccine |
| Group 2 | Experimental | Biological: RSVpreF VaccineRSVpreF Vaccine |
| Group 3 | Experimental | Biological: RSVpreF VaccineRSVpreF Vaccine |
| Group 4 | Experimental | Biological: RSVpreF VaccineRSVpreF Vaccine |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Participants ≥18 years of age who are/were immunocompromised at the time of initial RSVpreF vaccination, per study protocol, and will be grouped based on prior RSV vaccination history:
- Group 1 will include participants naïve to any RSV vaccine.
- Group 2 will include participants who received a single prior dose of RSVpreF (Abrysvo) approximately 1 year (9 to 15 months) prior to enrollment.
- Group 3 will include participants who received a single prior dose of RSVpreF (Abrysvo) approximately 2 years (21 to 27 months) prior to enrollment.
- Group 4 will include participants who previously received 2 doses of RSVpreF in Study C3671023 Substudy B approximately 3 years (36 to 42 months) prior to enrollment.
Key exclusion criteria (5 listed)
- Prior history of any subtype of Guillain-Barré Syndrome (GBS) of any etiology.
- History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis) to any components of the study intervention(s).
- Participants with a history of transplant rejection, or PTLD, or participants who have had treatment for these conditions, within 90 days prior to study enrollment or suspected chronic humoral or cellular rejection.
- Receipt of B-cell depleting therapies within 180 days prior to initial study vaccination.
- Refer to the study contact for further eligibility details.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| RSVpreF VaccineRSVpreF Vaccine | Biological | Group 1, Group 2, Group 3, Group 4 |
Primary outcome
Percentage of participants reporting local reactions
Time frame: For up to 7 days after vaccination
Percentage of participants reporting systemic events
Time frame: For up to 7 days after vaccination
Percentage of participants reporting adverse events
Time frame: Through 1 month after vaccination
Percentage of participants reporting newly diagnosed chronic medical conditions
Time frame: Through 12 months after vaccination
Percentage of participants reporting serious adverse events
Time frame: Through 12 months after vaccination
Neutralizing Titers (NTs) for RSV A and RSV B expressed as Geometric Mean Titer (GMT)
Time frame: Before vaccination, 1 month, 6 months and 12 months after vaccination
NTs for RSV A and RSV B expressed as Geometric Mean Fold Rise (GMFR)
Time frame: Before vaccination, 1 month, 6 months and 12 months after vaccination
1 secondary outcome
Seroresponse rate of NTs for RSV A and RSV B
Time frame: 1 month after revaccination
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Oct 2026.
- To obtain contact information for a study center near you, click here.Link provided by the sponsor.
- Individual participant dataSharing planned: Yes. Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Pfizer CT.gov Call Center study director
Pfizer
17 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing RSVpreF Vaccine in people with Respiratory Syncytial Virus (RSV), run by Pfizer at 17 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 14 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 17 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Pfizer CT.gov Call Center (1-800-718-1021, ClinicalTrials.gov_Inquiries@pfizer.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Percentage of participants reporting local reactions (time frame: For up to 7 days after vaccination). The study lists 7 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 Oct 2026.