A Study to Assess Safety, Tolerability and Immunogenicity of RSVpreF From Multidose Vials in Healthy Female Adults.
NCT Number: NCT06473519
Acronym: Amélie
Status: ACTIVE_NOT_RECRUITING
Study Type: INTERVENTIONAL
Phases: PHASE3
Conditions: Respiratory Syncytial Virus (RSV)
Interventions: BIOLOGICAL: RSVpreF MDV|BIOLOGICAL: RSVpreF SDV
Sponsor: Pfizer
Sex: FEMALE
Age: ADULT
Enrollment: 453
Study Design: Allocation: RANDOMIZED|Intervention Model: PARALLEL|Masking: NONE|Primary Purpose: PREVENTION
Start Date: 2024-06-24
Completion Date: 2024-09-14
Locations: Qps-Mra, Llc, South Miami, Florida, 33143, United States|Clinical Research Atlanta, Stockbridge, Georgia, 30281, United States|Clinical Research Prime, Idaho Falls, Idaho, 83404, United States|Clinical Research Prime Rexburg, Rexburg, Idaho, 83440, United States|Headlands Research - Detroit, Southfield, Michigan, 48034, United States|Clinical Trials of Texas, LLC dba Flourish Research, San Antonio, Texas, 78229, United States|Clinical Trials of Texas, LLC, San Antonio, Texas, 78229, United States

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.

Primary Outcome Measures: Primary Immunogenicity - Geometric mean titer (GMT) ratio estimated by the ratio of the GMTs for RSV A and RSV B serum neutralizing titers (NTs) with RSVpreF in MDV participants to that in the RSVpreF SDV participants, RSV A and RSV B NTs, expressed as GMTs. GMT ratio of the GMTs for RSV A and RSV B serum NTs with RSVpreF in MDV participants to that of RSVpreF in SDV participants., Before vaccination, and 1 month after vaccination|The proportion of participants reporting local reactions, Local reactions include pain at injection site, redness and swelling. Redness and swelling are measured and recorded in measuring device units. 1 measuring device unit =0.5 cm and graded as mild: \>2.0 to 5.0 cm, moderate: \>5.0 to 10.0 cm and severe: \>10 cm. Pain at injection site is graded as mild: did not interfere with daily activity, moderate: interfered with daily activity and severe: prevented daily activity., Baseline through Day 7|The proportion of participants reporting systemic events, Systemic events: fever, fatigue/tiredness, headache, nausea, muscle pain, joint pain, vomiting, diarrhea and any systemic event. Fever: greater than equal to (\>=)38.0 degrees (deg) Celsius (C), mild (\>=38.0 to 38.4 deg C), moderate (\>38.4 to 38.9 deg C), severe (\>38.9 to 40.0 deg C) and grade 4 (\>40.0 deg C). Fatigue, headache, nausea, muscle pain and joint pain are graded as mild: did not interfere with activity, moderate: some interference with activity and severe: prevented daily routine activity. Vomiting is graded as mild: 1 to 2 times in 24 hours(h), moderate: \>2 times in 24h and severe: requires intravenous hydration. Diarrhea is graded as mild: 2 to 3 loose stools in 24h, moderate: 4 to 5 loose stools in 24h and severe: 6 or more loose stools in 24h., Baseline through Day 7|The proportion of participants reporting adverse events, An AE is any untoward medical occurrence in a participant, temporally associated with the use of study vaccine, whether or not considered related to the study vaccine. AEs included serious and non-serious adverse events, and adverse events of special interest., Through 1 month after vaccination|The proportion of participants reporting serious adverse events, SAE is an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly; suspected transmission via a Pfizer product of an infectious agent., Throughout the study duration, up to 7 weeks.
Secondary Outcome Measures: Seroresponse rates by vaccine group, Seroresponse rates of RSV A and RSV B NTs, defined as a ≥ 4-fold rise in serum NTs at 1 month after vaccination compared to prevaccination; or ≥ 4 times the lower limit of quantitation (LLOQ) if prevaccination titer is below the LLOQ, 1 month after vaccination