NCT06551506

Brief Summary

Respiratory Syncytial Virus (RSV) is the leading cause of lower respiratory tract infections (LRTIs) in infants and young children. It is also a leading cause of mortality in children \<5 years of age worldwide. Until recently, no Food and Drug Administration (FDA)-approved vaccines were available to prevent RSV infection. The only prophylactic product for RSV prevention recommended for infants was the monoclonal antibody palivizumab, but administration was limited to those with extreme prematurity, chronic lung disease, or hemodynamically significant congenital heart disease. However, in 2023, the FDA approved two products designed to prevent RSV lower respiratory tract disease (LRTD) in all infants: an active RSV vaccine based on the prefusion F protein (RSVpreF, ABRYSVO, Pfizer) administered during pregnancy, and a passive, long-acting monoclonal antibody (nirsevimab-alip \[henceforth referred to as nirsevimab\], BEYFORTUS, AstraZeneca) administered to infants at birth or at the start of their first RSV season. Both products were evaluated in Phase 3 pivotal clinical trials and have high efficacy in preventing LRTD caused by RSV in infants. Although there is no established correlate of protection against RSV, antibodies have been associated with protection across multiple studies. The clinical development plan for the products did not include comprehensive evaluations of the magnitude and durability of the immune response, nor were the two products tested in a single trial. This study is a prospective, randomized, open-label Phase 4 study with the primary objective of evaluating the magnitude and durability of RSV-specific neutralizing antibodies in infants through 12 months of life following either maternal RSV vaccination, infant nirsevimab administration, or both products combined.

Trial Health

75
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
181

participants targeted

Target at P50-P75 for phase_4

Timeline
1mo left

Started Sep 2024

Geographic Reach
1 country

8 active sites

Status
active not recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress96%
Sep 2024May 2026

First Submitted

Initial submission to the registry

August 9, 2024

Completed
4 days until next milestone

First Posted

Study publicly available on registry

August 13, 2024

Completed
1 month until next milestone

Study Start

First participant enrolled

September 19, 2024

Completed
1.7 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

May 31, 2026

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

May 31, 2026

Last Updated

May 1, 2026

Status Verified

January 30, 2026

Enrollment Period

1.7 years

First QC Date

August 9, 2024

Last Update Submit

April 30, 2026

Conditions

Keywords

ABRYSVOBEYFORTUSImmunologyInfantsNirsevimabRespiratory syncytial virusRSVRSVpreF

Outcome Measures

Primary Outcomes (1)

  • Geometric mean titer (GMT) of serum RSV A and B neutralizing antibodies in infants

    GMT of RSV A and B neutralizing antibodies in infant serum at Day 1, 43, 91, 181, and 366. Day 1 infant specimen represents infant cord blood or serum (if unable to collect cord blood). Mother-infant pairs will be randomized 1:1 to either Day 43 or Day 91 blood collection.

    Through Day 366

Secondary Outcomes (12)

  • Frequency and relatedness of serious adverse events (SAEs) in each study arm (infants only)

    Through Day 181

  • Frequency and severity of unsolicited Grade 3 or higher related adverse events (AEs)

    Through 30 days following each nirsevimab dose

  • Frequency and severity of medically attended adverse events (MAAEs)

    Through 30 days following each nirsevimab dose

  • Geometric mean titer (GMT) of RSV A and B neutralizing antibodies in cord blood

    Day 1

  • Geometric mean titer (GMT) of RSV pre-F binding IgG antibodies in cord blood

    Day 1

  • +7 more secondary outcomes

Study Arms (4)

Group 1A

EXPERIMENTAL

Mother receives 120 mcg/0.5ml of maternal RSVpreF (ABRYSVO) administered intramuscularly once during 32 0/7 to 36 6/7 weeks GA and infant does NOT receive nirsevimab. N= 50.

Biological: Abrysvo

Group 1B

EXPERIMENTAL

Mother receives 120 mcg/0.5ml of maternal RSVpreF (ABRYSVO) administered intramuscularly once during 32 0/7 to 36 6/7 weeks GA and infant receives one dose of nirsevimab (BEYFORTUS) 50mg/0.5mL if body weight \<5kg or 100mg/mL if body weight is \>= 5kg at birth. N= 50.

Biological: AbrysvoBiological: Beyfortus

Group 1C

EXPERIMENTAL

Mother receives 120 mcg/0.5ml of maternal RSVpreF (ABRYSVO) administered intramuscularly once during 32 0/7 to 36 6/7 weeks GA and infant receives one dose of nirsevimab (BEYFORTUS) 50mg/0.5mL if body weight \<5kg or 100mg/mL if body weight is \>= 5kg at 3-month . N= 50.

Biological: AbrysvoBiological: Beyfortus

Group 2

EXPERIMENTAL

Mother does NOT receive maternal RSVpreF and infant receives one dose of nirsevimab (BEYFORTUS) 50mg/0.5mL if body weight \<5kg or 100mg/mL if body weight is \>= 5kg at birth . N= 50.

Biological: Beyfortus

Interventions

AbrysvoBIOLOGICAL

A maternal RSV vaccine based on the prefusion F protein administered during pregnancy

Group 1AGroup 1BGroup 1C
BeyfortusBIOLOGICAL

A passive, long-acting monoclonal antibody to Respiratory syncytial virus (RSV) administered to infants

Group 1BGroup 1CGroup 2

Eligibility Criteria

Age18 Years - 45 Years
Sexfemale
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • years of age at time of enrollment with an uncomplicated singleton pregnancy who are at no known increased risk for complications per clinical judgement of the investigator
  • Understands and agrees to comply with all study procedures
  • Willing and able to provide consent for study participation for themselves and their infant prior to initiation of any study procedures
  • In good health, as determined by the medical history and clinical judgment of the investigator Note: Healthy volunteers with pre-existing stable disease, defined as disease not requiring significant change in therapy or hospitalization for worsening disease during the 6 weeks before enrollment, can be included.
  • Intention to deliver at a hospital or birthing facility where study procedures can be performed
  • Eligible to receive either product per the FDA package inserts. (Maternal RSVpreF from 32 0/7 to 36 6/7 weeks gestational age (GA) from September 1 to March 31)

You may not qualify if:

  • Behavioral or cognitive impairment or psychiatric disease that, in the opinion of the investigator, may interfere with the participant's ability to participate in the study
  • Any condition which, in the opinion of the investigators, may pose a health risk for the participant or interfere with the evaluation of study objectives
  • Maternal bleeding diathesis, or any condition which may contraindicate intramuscular injection
  • Maternal known or suspected congenital or acquired disease that impairs the immune system, including functional asplenia or immunosuppression due to underlying illness or treatment
  • Maternal receipt of immunosuppressive drugs or biologic agents within 30 days prior to enrollment (This includes oral or parenteral corticosteroids. The use of inhaled/nebulized, intra-articular, intrabursal, or topical (skin, eye, ears) steroids are permitted. This does not include RhoGAM)
  • Maternal conditions known to impair transplacental transfer of maternal antibodies (e.g., placental pathology, hypergammaglobulinemia, HIV)
  • Maternal history of GBS or other potentially immune-mediated medical condition (PIMMC)
  • Maternal history of severe adverse reaction or anaphylaxis to ABRYSVO or its components
  • Maternal history of preterm birth (\<34 weeks GA)
  • Current pregnancy complicated by uncontrolled hypertension, pre-eclampsia, or eclampsia
  • Previous receipt of ABRYSVO or other approved or investigational RSV vaccine

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (8)

Emory University School of Medicine

Atlanta, Georgia, 30322-1014, United States

Location

University of Maryland, School of Medicine, Center for Vaccine Development and Global Health

Baltimore, Maryland, 21201-1509, United States

Location

New York University School of Medicine - Langone Medical Center - Vaccine Center

New York, New York, 10016-6402, United States

Location

University of Rochester Medical Center - Vaccine Research Unit

Rochester, New York, 14611-3201, United States

Location

Cincinnati Children's Hospital Medical Center Vaccine Research Center

Cincinnati, Ohio, 45229-3039, United States

Location

University of Pittsburgh - Medicine - Infectious Diseases

Pittsburgh, Pennsylvania, 15213-3108, United States

Location

Vanderbilt University Medical Center

Nashville, Tennessee, 37212, United States

Location

Baylor College of Medicine

Houston, Texas, 77030-3411, United States

Location

MeSH Terms

Conditions

Respiratory Syncytial Virus Infections

Interventions

abrysvonirsevimab

Condition Hierarchy (Ancestors)

Pneumovirus InfectionsParamyxoviridae InfectionsMononegavirales InfectionsRNA Virus InfectionsVirus DiseasesInfections

Study Design

Study Type
interventional
Phase
phase 4
Allocation
RANDOMIZED
Masking
NONE
Purpose
PREVENTION
Intervention Model
PARALLEL
Sponsor Type
NIH
Responsible Party
SPONSOR

Study Record Dates

First Submitted

August 9, 2024

First Posted

August 13, 2024

Study Start

September 19, 2024

Primary Completion (Estimated)

May 31, 2026

Study Completion (Estimated)

May 31, 2026

Last Updated

May 1, 2026

Record last verified: 2026-01-30

Locations