A Study to Assess Safety, Tolerability and Immunogenicity of RSVpreF From Multidose Vials in Healthy Female Adults.

NCT06473519 | Completed Phase 3 Results FDA Drug

• 2 other identifiers: C4841001NCT06473519
• Study Type: interventional
• Target: 453
• Locations: 1 country
• Sites: 6

Brief Summary

Respiratory Syncytial Virus (RSV) is a common type of virus (germ) that can cause severe illness, where medical help is needed. RSV can lead to airway diseases in all ages. Vaccines help your body make antibodies. These antibodies help fight against diseases. This is called an immune response. The purpose of this study is to learn about the safety, tolerability, and immunogenicity of a RSV vaccine called RSVpreF. RSVpreF comes either as:

• a single dose in a container (called a vial),
• or in a vial that holds multiple doses. A multidose vial contains more than one dose of RSVpreF. 2-Phenoxyethanol (2-PE) is a preservative to help prevent the growth of bacteria (germs). This study will compare RSVpreF with an added preservative called 2-phenoxyethanol (2-PE) from a multidose vial, to RSVpreF without an added preservative, from a single-dose vial. This study is looking to enroll nonpregnant, nonbreastfeeding, healthy female participants. Participants will need to visit the study clinic two times during the study. Participants will also have a final safety telephone call at the end of the study. All participants will receive a single shot of the study vaccine either from:
• a multidose vial (with the preservative), or
• from a single-dose vial (without the preservative) at the first study clinic visit. Blood samples will be taken at the two study clinic visits. Each participant will take part in the study for around 6 weeks.

Conditions

Respiratory Syncytial Virus (RSV)

Keywords

RSV infection; Multidose Vial (MDV); Single-dose Vial (SDV); 2-Phenoxyethanol (2-PE); Vaccines

Outcome Measures

Primary Outcomes (6)

• Geometric Mean Titer (GMT) of Serum Neutralizing Titers (NTs) for Respiratory Syncytial Virus Subgroup A (RSV A) and Respiratory Syncytial Virus Subgroup B (RSV B) Before Vaccination

  GMTs and corresponding 2-sided 95% confidence intervals (CIs) were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution).

  Before vaccination on Day 1

• GMT and Geometric Mean Ratio (GMR) of Serum NTs for RSV A and RSV B at 1 Month After Vaccination

  GMTs and corresponding 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). GMTs of NTs for RSV A and B were reported in the descriptive data section of this outcome measure. GMR each for RSV A and RSV B was calculated as ratio of NTs of RSVpreF (MDV) to RSVpreF (SDV) and was reported in the statistical analysis section of this outcome measure.

  1 month after Vaccination on Day 1

• Percentage of Participants With Local Reactions Within 7 Days After Vaccination

  Local reactions included redness, swelling and pain at injection site, reported in the electronic diary (e-diary) and the participant-reported reactogenicity (PARREACT) case report form (CRF). Redness and swelling were measured and recorded in measuring device units, where 1 measuring device unit= 0.5 centimeter (cm) and graded as mild: \>2.0 to 5.0 cm, moderate: \>5.0 to 10.0 cm, severe: \>10.0 cm, Grade 4: necrosis (redness and swelling) or exfoliative dermatitis (redness). Pain at injection site was graded as mild: did not interfere with activity, moderate: interfered with activity, severe: prevented daily activity, Grade 4: emergency room visit or hospitalization for severe pain at injection site.

  Day 1 through Day 7 after Vaccination

• Percentage of Participants With Systemic Events Within 7 Days After Vaccination

  Systemic events included fever, fatigue, headache, vomiting, nausea, diarrhea, muscle pain and joint pain, recorded in the e-diary and PARREACT CRF. Fever measured in degree Celsius and ranged: mild (38.0 - 38.4); moderate (38.5 - 38.9); severe (39.0 - 40.0); Grade 4: \>40.0. Fatigue, headache, nausea, muscle and joint pain graded as: mild (didn't interfere with activity); moderate (some interference with activity); severe (prevented daily routine activity); Grade 4 \[emergency room (ER) visit or hospitalization). Vomiting graded as: mild (1-2 times in 24 hours\[h\]); moderate (\>2 times in 24h); severe (required intravenous hydration); Grade 4 (ER visit or hospitalization). Diarrhea graded as: mild (2-3 loose stools in 24h); moderate (4-5 loose stools in 24h); severe (6 or more loose stools in 24h); Grade 4 (ER visit or hospitalization).

  Day 1 through Day 7 after Vaccination

• Percentage of Participants With Adverse Events (AEs) Within 1 Month After Vaccination

  An AE was defined as any untoward medical occurrence in a participant temporally associated with the use of study intervention, whether or not considered related to the study intervention were included in evaluation of this outcome measure. AEs included both serious AEs (SAEs) and all non-SAEs. Events collected by systematic assessment (local reactions and systemic events) were excluded from evaluation.

  Within 1 Month after Vaccination

• Percentage of Participants With SAEs Throughout the Study

  An AEs was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention. An SAE was defined as any untoward medical occurrence that, at any dose, met one or more of the following criteria - resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect and other important medical events per protocol of the study. Events collected by systematic assessment (local reactions and systemic events) were excluded from evaluation.

  Within 42 to 49 days after Vaccination on Day 1 (maximum up to 1.6 months)

Secondary Outcomes (1)

• Percentage of Participants Achieving Seroresponse for RSV A and RSV B of Serum NTs at 1 Month After Vaccination

  1 Month after Vaccination

Study Arms (2)

RSVpreF multidose vial (MDV)

EXPERIMENTAL

RSVpreF with 2-PE formulated in an MDV

Biological: RSVpreF MDV

RSVpreF single-dose vial (SDV)

EXPERIMENTAL

RSVpreF without 2-PE formulated in an SDV

Biological: RSVpreF SDV

Interventions

RSVpreF MDV BIOLOGICAL

RSVpreF with 2-PE formulated in an MDV

RSVpreF multidose vial (MDV)

RSVpreF SDV BIOLOGICAL

RSVpreF without 2-PE formulated in an SDV

RSVpreF single-dose vial (SDV)

Eligibility Criteria

• Age: 18 Years - 49 Years
• Gender Eligibility Details: Nonpregnant, nonbreastfeeding females
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy nonpregnant, nonbreastfeeding females 18 through 49 years of age at Visit 1 (Day 1).
• Willing and able to comply with all scheduled visits, investigational plan, lifestyle considerations, and other study procedures.
• Available for the duration of the study and can be contacted by telephone during study participation.
• Capable of giving signed informed consent as described in the protocol which includes compliance with the requirements and restrictions listed in the ICD and in the protocol.

You may not qualify if:

• Any medical or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior or laboratory abnormality that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study.
• History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis) to any component of the vaccines being administered in the study.
• Immunocompromised participants with known or suspected immunodeficiency, as determined by history, laboratory tests, and/or physical examination.
• History or active autoimmune disease, including but not limited to systemic or cutaneous lupus erythematosus, autoimmune arthritis/rheumatoid arthritis, Guillain-Barré syndrome, multiple sclerosis, Sjögren's syndrome, idiopathic thrombocytopenia purpura, glomerulonephritis, autoimmune thyroiditis, giant cell arteritis (temporal arteritis), psoriasis, and insulin-dependent diabetes mellitus (type 1).
• Bleeding diathesis or any condition that would, in the opinion of the investigator, contraindicate intramuscular injection.
• Previous vaccination with any licensed or investigational RSV vaccine, or planned receipt of a nonstudy RSV vaccine throughout the study.
• Receipt of chronic systemic treatment with immunosuppressant medications (including cytotoxic agents or systemic corticosteroids), or radiotherapy, within 60 days before enrollment through conclusion of the study.
• Receipt of blood/plasma products or immunoglobulin within 60 days before study intervention administration or planned receipt throughout the study.
• Current alcohol abuse or illicit drug use.
• Individuals who are pregnant or breastfeeding.
• Participation in other studies involving an investigational product within 28 days prior to study entry and/or during study participation. Participation in purely observational studies is acceptable.
• Investigator site staff directly involved in the conduct of the study and their family members, site staff otherwise supervised by the investigator, and sponsor and sponsor delegate employees directly involved in the conduct of the study and their family members.

Sponsors & Collaborators

• Pfizer: lead

Study Sites (6)

Qps-Mra, Llc

South Miami, Florida, 33143, United States

Location

Clinical Research Atlanta

Stockbridge, Georgia, 30281, United States

Location

Clinical Research Prime

Idaho Falls, Idaho, 83404, United States

Location

Clinical Research Prime Rexburg

Rexburg, Idaho, 83440, United States

Location

Headlands Research - Detroit

Southfield, Michigan, 48034, United States

Location

Clinical Trials of Texas, LLC dba Flourish Research

San Antonio, Texas, 78229, United States

Location

Related Links

• To obtain contact information for a study center near you, click here.

MeSH Terms

Conditions

Respiratory Syncytial Virus Infections

Condition Hierarchy (Ancestors)

Pneumovirus Infections; Paramyxoviridae Infections; Mononegavirales Infections; RNA Virus Infections; Virus Diseases; Infections

Results Point of Contact

• Title: Pfizer ClinicalTrials.gov Call Center
• Organization: Pfizer Inc.

ClinicalTrials.gov.Inquiries@pfizer.com

1-800-718-1021

Study Officials

• Pfizer CT.gov Call Center

  Pfizer

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: OTHER
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: NONE
• Masking Details: Open-label
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 17, 2024
• First Posted: June 25, 2024
• Study Start: June 24, 2024
• Primary Completion: September 20, 2024
• Study Completion: September 20, 2024
• Last Updated: September 25, 2025
• Results First Posted: September 25, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will share

Locations

US (6)