Exploring a new influenza A H3N2 virus challenge

An Exploratory Study to Establish the Dose, Safety and Pathogenicity of a New Influenza a H3N2 Challenge Strain in Healthy Participants 18 to 55 Years of Age

Not applicable Interventional Hvivo · NCT06613737

This study is testing a new strain of the flu virus in healthy adults aged 18 to 55 to see how safe it is and what dose works best.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment80 (estimated)
Ages18 Years to 55 Years
SexAll
SponsorHvivo Industry-sponsored
Locations1 site (London)
Trial IDNCT06613737 on ClinicalTrials.gov

What this trial studies

This exploratory study aims to establish the dose, safety, and pathogenicity of a new influenza A H3N2 challenge strain in healthy participants aged 18 to 55. The study consists of two parts: Part A will randomly allocate up to 40 participants to receive one of two virus doses, while Part B may involve additional participants receiving one of the established doses or a new dose based on Part A's outcomes. Participants will undergo a series of clinical assessments and safety monitoring during their stay in a quarantine unit for approximately 8 days following inoculation.

Who should consider this trial

Good fit: Ideal candidates are healthy adults aged 18 to 55 with a body weight of at least 50 kg and a BMI between 18 and 35.

Not a fit: Patients with a history of respiratory infections or significant medical conditions may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved understanding and management of influenza A H3N2 infections.

How similar studies have performed: Other studies have shown success with similar human challenge approaches in understanding influenza viruses.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Written informed consent
* Adult male or female aged between 18 and 55 years
* A total body weight ≥50 kg and body mass index (BMI) ≥18 kg/m2 and ≤35kg/m2.
* In good health with no history, or current evidence, of clinically significant medical conditions, and no clinically significant test abnormalities that will interfere with participant safety.
* Documented medical history
* Adherence to contraception requirements
* Serosuitable for the challenge virus

Exclusion Criteria:

* History of, or currently active, symptoms or signs suggestive of upper or lower respiratory tract (LRT) infection within 4 weeks prior to the first study visit.
* Any history or evidence of any clinically significant or currently active disease.
* Any participants who have smoked ≥10 pack years at any time.
* Female participants who are breastfeeding, or have been pregnant within 6 months prior to the study, or have a positive pregnancy test at any point during screening or prior to inoculation.
* Any history of anaphylaxis and/or a any history of severe allergic reaction.
* Venous access deemed inadequate for the phlebotomy and cannulation demands of the study.
* Lifetime history of anaphylaxis and/or a lifetime history of severe allergic reaction.
* Significant abnormality of the nose, includes loss of or alterations in smell or taste, nasal polyps, epistaxis, nasal or sinus surgery.
* Recent vaccinations or intention to receive vaccination before the Day 28 follow up visit.
* Receipt of blood or blood products, or loss (including blood donations) of 550 mL or more of blood during the 3 months prior to the planned inoculation or planned during the 3 months after the final visit.
* Recent receipt of investigational drugs or challenge viruses.
* Use or anticipated use during the conduct of the study of concomitant medications (prescription and/or non-prescription), including vitamins or herbal and dietary supplements within the specified windows.
* Positive drugs of abuse test, recent history or presence of alcohol addiction, excessive consumption of xanthine containing substances or a presence of significant signs and symptoms of nicotine withdrawal on first study visit.
* A forced expiratory volume in 1 second (FEV1) \<80%.
* Positive HIV, hepatitis B virus, or hepatitis C virus test.
* Presence of fever, defined as participant presenting with a temperature reading of ≥37.9°C on Day -2/-1 and/or pre-inoculation on Day 0.
* Those employed or immediate relatives of those employed at hVIVO or the sponsor.
* Any other reason, in the opinion of the investigator deems the participant unsuitable for the study

Where this trial is running

London

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Influenza a H3N2InfluenzaFluH3N2Human Challenge Trial
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.