Recruiting
Phase 3

H5N1 Vaccine

Sponsor:

University Health Network, Toronto

Code:

NCT07240558

Conditions

Influenza (Pandemic)

Avian Influenza

Vaccination

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

H5N1 vaccine (Arepanrix, GSK)

Placebo

Study Details

Brief summary:

Influenza is an important pathogen in transplant recipients. The current widespread outbreak of highly pathogenic H5N1 avian influenza (HPAI) in livestock, and the occurrence of several human cases of infection suggest that the next influenza pandemic may be soon approaching. Transplant patients will likely be uniquely predisposed to serious infection with high morbidity and mortality. There are a number of important reasons that evaluation of prevention strategies are critical in this highly vulnerable population. Currently, there is no data on the immunogenicity of H5Nx vaccines in this highly vulnerable population. The investigators plan to study the safety and immunogenicity of a two-dose regimen of the pandemic influenza H5N1 vaccine in organ transplant patients.

Conditions

Influenza (Pandemic)

Avian Influenza

Vaccination

Study ID

NCT07240558

Start date

Nov 3, 2025

Status verified date

Dec, 2025

Completion date

Dec 31, 2026

Anticipated

Primary completion date

Jun 30, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Age ≥ 18 and greater than 3 months post-transplant
  • Stable graft function
  • eGFR >30mL/min/1.73m2
  • Able to provide informed consent

Exclusion Criteria:

  • Allergy to vaccine components;
  • Previous life-threatening reaction to influenza vaccine (ie Guillain Barré Syndrome);
  • Ongoing or recent therapy for acute rejection (within the previous 30 days);
  • Ongoing active cytomegalovirus (CMV) infection with viral load of greater or equal to 1000 international units/ml in the last 7 days;
  • Febrile illness in the past 2 weeks;
  • Rituximab in the last 6 months;
  • Receiving treatment for active or acute infection;
  • Unable to provide informed consent;
  • 2025 seasonal influenza vaccination in preceding 6 weeks;
  • Recent other vaccination in last 14 days;
  • Receipt of intravenous immunoglobulin in last 30 days or expected to receive in next 30 days; Life expectancy < 3 months;
  • Diagnosis of influenza virus infection in the last 90 days.
  • Pregnancy known at the time of enrolment

Study Design

Enrollment

120 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Prevention

Interventions and Outcome Measures

Arms

active comparator: H5N1 vaccine

This arm will receive 2 doses of approved H5N1 vaccine, 3 weeks apart

placebo comparator: Placebo

This arm will receive 2 doses of normal saline (placebo), 3 weeks apart

Interventions

H5N1 vaccine (Arepanrix, GSK)

2 doses of H5N1 vaccine, 3 weeks apart, given IM (deltoid)

Placebo

2 doses of 0.5mls normal saline, 3 weeks apart, given IM (deltoid)

Primary outcome measure

  • Seroprotection and seroconversion 6 weeks after dose 1 [ Time Frame: 6 weeks after dose 1 and 3 weeks after dose 2 ]

Central Contacts and Locations

Central contacts

Victoria G Hall, MBBS MPH

1 416 340 4800victoria.hall@uhn.ca

Locations

University Health Network

Recruiting

Toronto, Ontario, Canada, M5G2N2

Contacts

Victoria G Hall, MBBS MPH

4163404800victoria.hall@uhn.ca

Principal Investigator:

Victoria G Hall, MBBS MPH

More Information

Sponsor

University Health Network, Toronto

Last update posted

Dec 18, 2025

Last verified

Dec, 2025

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University Health Network, Toronto on 2025-12-18.