Phase 3 Randomized, Modified Double-blind, Active-controlled Safety Study on vYF in Adults

NCT07002060 | Completed Phase 3 FDA Drug

• 1 other identifier: VYF00019
• Study Type: interventional
• Target: 640
• Locations: 1 country
• Sites: 7

Brief Summary

The purpose of this study is to assess the safety of vYF (investigational vaccine) compared to the safety of YF-VAX (YF licensed vaccine) in adults aged 18 years up to 60 years. Study details include:

• The study duration will be up to approximately 6 months.
• One single dose of the study intervention (vYF or YF-VAX) will be administered subcutaneously at the 1st visit.
• The visit(V) frequency will be Day(D) 01 (V01) and D29 (V02). Two telephone calls will be planned at D15 and Month(M)6. Number of Participants: A total of 640 participants are expected to be included in the study in a 3:1 ratio (vYF: YF-VAX): Group 1: vYF; N=480 Group 2: YF-VAX; N=160 Study Arms and Duration: Randomized, active control (YF-VAX). 6 months duration per participants. Eligible participants will be randomized in a 3:1 ratio to receive, subcutaneously, a single dose of vYF or YF-VAX vaccines on D01.

Conditions

Yellow Fever Immunization

Keywords

Yellow fever

Outcome Measures

Primary Outcomes (7)

• Number of participants with immediate adverse events

  Immediate adverse events are any unsolicited systemic adverse events reported in the 30 minutes after vaccination

  Within 30 minutes after vaccination

• Number of participants with solicited injection site reactions

  Solicited injection site reactions include injection site pain, erythema and swelling

  Up to 7 days after vaccination

• Number of participants with solicited systemic reactions

  Solicited systemic reactions include fever, headache, malaise and myalgia

  Up to 14 days after vaccination

• Number of participants with unsolicited adverse events (AEs)

  Unsolicited (spontaneously reported) AEs, not fulfilling criteria for solicited adverse reactions

  Up to 28 days after vaccination

• Number of participants with medical attended adverse events (MAAEs)

  MAAEs

  Up to 28 days after vaccination

• Number of participants with adverse events of special interest (AESIs)

  AESIs

  Up to 6 months after vaccination

• Number of participants with serious adverse events (SAEs)

  SAEs

  Up to 6 months after vaccination

Study Arms (2)

vYF vaccine

EXPERIMENTAL

A single dose on Day 01

Biological: Yellow fever vaccine (live)

YF-VAX vaccine

ACTIVE COMPARATOR

A single dose on Day 01

Biological: YF vaccine (live)

Interventions

Yellow fever vaccine (live) BIOLOGICAL

Powder and solvent for solution for injection Subcutaneous

Also known as: vYF vaccine

vYF vaccine

YF vaccine (live) BIOLOGICAL

Powder and diluent for suspension for injection Subcutaneous

Also known as: YF-VAX vaccine, YF-VAX

YF-VAX vaccine

Eligibility Criteria

• Age: 18 Years - 59 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Participants who are healthy as determined by medical evaluation including medical history and physical examination
• A female participant is eligible to participate if she is not pregnant or breastfeeding and one of the following conditions applies:
• Is of non-childbearing potential. To be considered of non-childbearing potential, a female must be post-menopausal for at least 1 year, or surgically sterile.
• Is of childbearing potential and agrees to use an effective contraceptive method or abstinence from at least 4 weeks prior to study intervention administration until at least 12 weeks after study intervention administration.
• A female participant of childbearing potential must have a negative highly sensitive pregnancy test (urine or serum as required by local regulation) before any dose of study intervention on D01 and will be repeated on D29 to confirm the participant is still not pregnant within the 28 days of vaccine administration
• Able to attend all scheduled visits and to comply with all study procedures Informed consent
• Informed consent form has been signed and dated

You may not qualify if:

• Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy, within the preceding 6 months; or long-term systemic corticosteroid therapy (prednisone or equivalent for more than 2 consecutive weeks within the past 3 months)
• Known history of laboratory evidence of HIV infection
• Known history of hepatitis B or hepatitis C seropositivity
• Known history of flavivirus (FV) infection
• Known systemic hypersensitivity to any of the study intervention components, or history of a life-threatening reaction to the vaccine used in the study or to a vaccine containing any of the same substances
• Personal or family history of thymic pathology (thymoma, thymectomy, or myasthenia)
• Chronic illness that, in the opinion of the investigator, is at a stage where it might interfere with trial conduct or completion , including malignancy, such as leukemia or lymphoma
• Moderate or severe acute illness/infection (according to Investigator judgment) on the day of vaccination or febrile illness (temperature ≥ 38°C \[or ≥ 100.4°F\]). A prospective participant should not be included in the study until the condition has resolved or the febrile event has subsided.
• Alcohol, prescription drug, or substance abuse that, in the opinion of the Investigator, might interfere with the study conduct or completion
• Receipt of any vaccine in the 4 weeks preceding the study vaccination or planned receipt of any vaccine in the 4 weeks following the study vaccination (prior to Visit 2 on D29), except for influenza vaccination, which may be received at least 2 weeks before study vaccine. This exception includes pandemic influenza vaccines including monovalent pandemic influenza vaccines.
• Previous vaccination against a FV disease at any time including yellow fever (YF) with an investigational or marketed vaccine
• Receipt of immune globulins, blood or blood-derived products in the past 6 months
• Administration of any anti-viral within 2 months preceding the vaccination and up to the 6 weeks following the vaccination
• Participation at the time of study enrollment (or in the 4 weeks preceding the study vaccination) or planned participation during the course of the study in another clinical study investigating a vaccine, drug, medical device, or medical procedure
• Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily

Sponsors & Collaborators

• Sanofi: lead

Study Sites (7)

The Hope Clinic of Emory University- Site Number : 8400006

Decatur, Georgia, 30030, United States

Location

Velocity Clinical Research-New Orleans- Site Number : 8400004

New Orleans, Louisiana, 70119, United States

Location

Johns Hopkins Bloomberg School of Public Health- Site Number : 8400009

Baltimore, Maryland, 21205, United States

Location

Saint Louis University Center for Vaccine Development- Site Number : 8400001

St Louis, Missouri, 63104, United States

Location

Rochester Clinical Research- Site Number : 8400005

Rochester, New York, 14610, United States

Location

Velocity Clinical Research - Providence- Site Number : 8400003

East Greenwich, Rhode Island, 02818, United States

Location

J. Lewis Research, Inc. / Foothill Family Clinic

Salt Lake City, Utah, 84109, United States

Location

Related Links

• VYF00019 Plain Language Results Summary

MeSH Terms

Conditions

Yellow Fever

Interventions

Yellow Fever Vaccine

Condition Hierarchy (Ancestors)

Mosquito-Borne Diseases; Vector Borne Diseases; Infections; Arbovirus Infections; Virus Diseases; Flavivirus Infections; Flaviviridae Infections; RNA Virus Infections; Hemorrhagic Fevers, Viral

Intervention Hierarchy (Ancestors)

Viral Vaccines; Vaccines; Biological Products; Complex Mixtures

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Participants, Sponsor study staff, investigators and study staff, will remain blinded during the study conduct, except dedicated study staff preparing/administering the study interventions and who are not involved in the safety evaluation.
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 23, 2025
• First Posted: June 3, 2025
• Study Start: May 22, 2025
• Primary Completion: January 20, 2026
• Study Completion: January 20, 2026
• Last Updated: February 2, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will share

Locations

US (7)