AzTrials
AzTrials

Influenza (Healthy Volunteers)Phase 1NCT07305207

Establishing a Controlled Human Infection Model for Influenza H3N2 as a Foundation for Pandemic Preparedness

A Phase 1 study testing Intranasal inoculation of RG-A/Texas/71/2017 (H3N2) influenza in each naris on Day 1 of the study. in people with Influenza (Healthy Volunteers), run by Dalhousie University at 1 site in Canada.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
Search all trials

Trial summary

The overall objective is to establish an influenza Controlled Human Infection Model (CHIM) in Canada that can be used to assess the safety and efficacy of candidate vaccines, biologics, and therapeutics targeting influenza viruses. Read more about this study

Who is it for?
Ages 18 to 45 yearsHealthy volunteers can take part
Conditions the study is for
Influenza (Healthy Volunteers)
What is being tested?
Intranasal inoculation of RG-A/Texas/71/2017 (H3N2) influenza in each naris on Day 1 of the study.
Could I receive a placebo?
No, everyone receives an active treatment
How many people
32 participants
Where
1 siteCanada
Study dates
1 Jun 2026to 31 Jan 2028
Phase
Phase 1
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 45 years
  • All sexes
  • Healthy volunteers accepted
  • Adult

Who may be able to join

  • Written informed consent obtained from the participant.
  • 18-45 years of age.
  • Good general health status, as determined by history and physical examination conducted no longer than 30 days prior to the challenge date.
  • HAI antibody titer ≤1:40 against influenza A/Texas/71/2017 (H3N2).
  • Eligibility laboratory values* (complete blood cell count with differential (CBC-D), biochemistry (creatinine (Cr), total bilirubin, blood urea nitrogen (BUN), aspartame aminotransferase (AST), alanine transaminase (ALT), and c-reactive protein (CRP))*Labs within normal range or grade 1 abnormalities deemed not clinically significant by a study investigator are considered acceptable.
  • Vital signs** as follows:
Show all 27Show fewer
  • Pulse is 47 to 99 beats per minute
  • Systolic blood pressure is 85 to 139 mmHg
  • Diastolic blood pressure is 55 to 89 mmHg
  • SpO2 ≥ 95%; RR ≤ 18
  • Oral temperature is less than 38.1°C **Clinical judgement when characterizing vital signs will be used in the context of certain populations according to the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials (e.g. conditioned athletes, white coat hypertension etc.)
  • If a person is at risk of becoming pregnant, has practiced adequate contraception for 28 days prior to challenge, and has a negative pregnancy test on the screening day and the day before influenza A/H3N2 challenge (Check-in Day) and has agreed to continue adequate contraception until 60 days after challenge.
  • Risk of pregnancy is defined as any individual assigned female at birth or with reproductive capacity who is sexually active with individuals with sperm-producing capabilities. Individuals who have received the following are considered to not have reproductive capacity:
  • Documented hysterectomy
  • Documented bilateral salpingectomy
  • Documented bilateral oophorectomy
  • Documented and current bilateral tubal ligation or occlusion
  • Credible self-reported history of diagnosed infertility
  • Hormone therapy (e.g. testosterone), provided it is administered consistently and medically assessed as sufficient to reduce pregnancy such that ovulation has ceased
  • Any other condition, as determined by the Principal Investigator/study physician, that would render an individual incapable of becoming pregnant
  • Adequate contraception is defined as a contraceptive method with a failure rate of <1% per year when used consistently and correctly and, when applicable, in accordance with the product label. Examples include the following:
  • Combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation: oral, intravaginal, or transdermal
  • Progestogen-only hormonal contraception associated with inhibition of ovulation: oral, injectable, or implantable CI2403.03November2025_V3.0 52
  • Intra-uterine device (IUD) with or without hormonal release
  • Vasectomized partner, if this is the participant's sole partner and the partner has received a medical assessment of the surgical success
  • Credible (as deemed by the Investigator/study physician) self-reported history of abstinence for at least 28 days prior to challenge
  • Participants who, in the opinion of the Investigator/study physician, can and will comply with the requirements of the protocol (e.g., inpatient stay, complete eDiary Cards, return for follow-up visits).

Who cannot join

  • Underlying chronic medical condition requiring ongoing follow-up and monitoring by a physician (e.g., diabetes, seizure disorder).
  • Underlying renal disease or disorders requiring ongoing follow-up and monitoring by a physician. In the event a participant has a minimally elevated BUN and/or Cr at screening, the participant will either be excluded or an eCRF or creatinine clearance may be conducted to determine eligibility.
  • Underlying coagulation disorder history. In the event a participant reports a personal history of undiagnosed prolonged bleeding and/or recurrent nosebleeds or a personal or family history of coagulation disorders, a bleeding panel (PTT, INR, fibrinogen) will be used to rule out coagulopathy.
  • Underlying cardiac conditions including:
  • Hypertension, angina, or prior myocardial infarction
  • Structural or functional cardiac disease (e.g., dilated cardiomyopathy, congestive heart failure)
Show all 41Show fewer
  • With a history of arrhythmias/dysrhythmias (e.g., torsades de pointes, atrial fibrillation)
  • Cardiac conduction abnormalities (e.g., congenital or acquired heart block)
  • Uncorrected or ongoing serum electrolyte abnormalities (e.g., hypokalemia, hypomagnesemia, hypocalcemia)
  • Underlying pulmonary disease including asthma, emphysema, chronic bronchitis, pulmonary tuberculosis or any other structural or functional pulmonary condition (e.g., history of severe airway hyper-responsiveness).
  • FEV1/FEV6 < 0.73 as an indication of potential airflow limitation.
  • Known allergy to excipients in the challenge virus inoculum and placebo. The excipient (diluent and placebo) is SPG: sucrose, KH2PO4, K2HPO4, L-glutamic acid.
  • Moderate or severe symptoms of health anxiety, anxiety, and mood symptoms. Self-reported current diagnosis of a major psychiatric illness, including, but not limited to, a schizophrenia spectrum disorder, bipolar disorder, posttraumatic stress disorder, obsessive compulsive disorder, substance use disorder, or eating disorder, based on standardized mental health screening tools.
  • Habitual* smoker of tobacco, e-cigarettes or marijuana. *Habitual smokers are those who smoke more than four cigarettes, other tobacco products, e-cigarettes (to include vaping and Juuling products) or marijuana in a week and cannot agree to abstain from smoking cigarettes, other tobacco products, e-cigarettes and/or marijuana products during participation in the study.
  • Any current daily use of illicit drugs whereby the individual and/or study staff assess that the individual cannot abstain from during the isolation period.
  • Any current daily alcohol consumption whereby the individual and/or study staff assess that the individual cannot abstain during the isolation period.
  • History of allergic rhinitis and/or any condition that causes similar symptoms, including chronic cough.
  • Pregnant (known before or established at the time of screening using a urine pregnancy test) or breastfeeding.
  • Immunocompromised (with HIV/AIDS or receiving immunosuppressive therapy involving steroids) or any medical condition or medication that leads to a compromised immune system.
  • Screening blood work positive for HBV, HCV, or HIV.
  • Influenza virus detected in NPS sample prior to challenge using RT-qPCR and/or culture isolation, or detection of other respiratory infection.
  • Received influenza vaccination within the last 4 months prior to screening based on history described by participant or planned receipt up to Study Day 57.
  • Living with, working with, or in close contact with children less than 6 months of age, or a household member(s) highly recommended to receive an annual influenza vaccination by NACI**** and that have not been immunized with influenza vaccine within the last year or immunized less than 3 weeks prior to challenge.
  • Individuals that are highly recommended by NACI to receive an influenza vaccine and potentially at risk include the following (52): (52):
  • All children 6-59 months of age
  • Adults and children with the following chronic health conditions:
  • Cardiac or pulmonary disorders (including bronchopulmonary dysplasia, cystic fibrosis and asthma) ii. Diabetes mellitus and other metabolic diseases iii. Cancer, immune compromising conditions (due to underlying disease, therapy, or both, such as solid organ transplant or hematopoietic stem cell transplant recipients) iv. Renal disease v. Anemia or hemoglobinopathy vi. Neurologic or neurodevelopmental conditions (includes neuromuscular, neurovascular, neurodegenerative, neurodevelopmental conditions and seizure disorders [and, for children, includes febrile seizures and isolated developmental delay], but excludes migraines and psychiatric conditions without neurological conditions) vii. Morbid obesity (defined as Body Mass Index (BMI) ≥ 40 kg/m2) viii. Children six months to 18 years of age undergoing treatment for long periods with acetylsalicylic acid, because of the potential increase of Reye syndrome associated with influenza c. All individuals who are pregnant d. All individuals of any age who are residents of nursing homes and other chronic care facilities e. Adults 65 years of age and older f. Indigenous Peoples
  • Any contraindication to receiving oseltamivir or zanamivir including known history of negative/anaphylactic reactions. Inability to take capsules containing gelatin or sorbitol (oseltamivir) or lactose-intolerant (zanamivir)
  • Recent (within the 6 months before Screening Day) nasal or sinus surgery or diagnosis with nasal polyps.
  • Recent use (4 weeks of Screening Day) of intranasal steroids, antihistamines, or any substance (including legally prohibited or prescription drug) that is administered nasally.
  • Receipt of any investigational drug or vaccine within 6 months prior to challenge. An investigational drug or vaccine is one that is still being tested in clinical trials that has not yet been authorized for use in Canada for administration by public programs.
  • Receipt of any authorized vaccines within 2 weeks prior to being challenged.
  • Previous moderate or severe laboratory-confirmed SARS-CoV-2/COVID-19, influenza infection, or any other respiratory virus infection (e.g., RSV) that required hospitalization.
  • Head trauma (e.g., fracture of the cribriform plate) within 1 year of screening.
  • Symptoms indicative of acute respiratory illness (such as fever, cough, difficulty breathing) identified during the physical examination done on Study Day -1 (check-in) or Day 1 before a participant is challenged. In the event a participant reports changes to their medical history since screening up until check-in, a history-directed respiratory panel will be administered and any positive respiratory virus including SARS-COV-2 will be exclusionary
  • History of Bell's Palsy, Guillain-Barre, and/or facial paralysis.
  • Receipt of facial cosmetic filler, or any facial neuromodulator, in the past 3 months.
  • Self-reported sleep apnea that requires a continuous positive airway pressure (cPap) machine
  • Receipt of blood or blood products during the six months prior to the planned date of challenge.
  • Plans to donate blood anytime throughout the study.
  • Any other finding that the Investigator/study physician considers will make the participant unsuitable for the study or unable to comply with the study requirements.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Nick Bartlett contact

902-470-8141

nicholas.bartlett@iwk.nshealth.ca

Hannah Munday contact

902-470-8141

hannah.munday@iwk.nshealth.ca

Canada1 site, 1 recruiting

  • Canadian Center for Vaccinology

    Halifax, Nova Scotia, B3K 6R8

    Nicholas Bartlett, 902-470-8141, nicholasjonbartlett@iwk.nshealth.ca

    Scott Halperin

    Recruiting

Other trials in Canada

About this study

Official title: A Double-blinded, Phase 1 Clinical Trial to Establish an RG-A/Texas/71/2017 (H3N2) Influenza Controlled Human Infection Model (CHIM) That Safely and Reproducibly Induces Symptomatic Influenza Virus Infection in Healthy Adults 18-45 Years of Age After Intranasal Challenge

The overall objective is to establish an influenza Controlled Human Infection Model (CHIM) in Canada that can be used to assess the safety and efficacy of candidate vaccines, biologics, and therapeutics targeting influenza viruses.

Being tested
Intranasal inoculation of RG-A/Texas/71/2017 (H3N2) influenza in each naris on Day 1 of the study.
Keywords
human challenge, Controlled human infection model, Influenza, intranasal challenge, Phase 1 clinical trial, Immune response
Medical subject headings
Influenza, Human

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Intranasal inoculation of RG-A/Texas/71/2017 (H3N2) influenza in each naris on Day 1 of the study.Biological

    Participants will be inoculated intranasally with a single dose of the A/H3N2 challenge virus or placebo

Study groups in NCT07305207
Study groupRoleWhat they receive
Experimental: Group 1: Dose Number 1 (10^5)ExperimentalParticipants will be inoculated intranasally with a single dose of the A/H3N2 challenge virus or placebo
Receives: Biological: Intranasal inoculation of RG-A/Texas/71/2017 (H3N2) influenza in each naris on Day 1 of the study.
Experimental: Group 1: Dose Number 2 (10^4)ExperimentalParticipants will be inoculated intranasally with a single dose of the A/H3N2 challenge virus or placebo
Receives: Biological: Intranasal inoculation of RG-A/Texas/71/2017 (H3N2) influenza in each naris on Day 1 of the study.
Experimental: Group 1: Dose Number 3 (10^6)ExperimentalParticipants will be inoculated intranasally with a single dose of the A/H3N2 challenge virus or placebo
Receives: Biological: Intranasal inoculation of RG-A/Texas/71/2017 (H3N2) influenza in each naris on Day 1 of the study.

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Symptomatic influenza-virus infection

    Viral shedding (as determined by a detectable quantitative RT-qPCR result on at least two days and/or at least one positive culture) beginning 24 hours after challenge (Study Day 2) until Study Day 8 and a cumulative symptom score of ≥6 from daily component symptoms computed across any consecutive 5-day window starting on Study Day 2 up to Study Day 8 post-challenge using a Modified Jackson Score (MJS).

    Measured: Study Day 2 until Study Day 8

Secondary outcomes (8)

  1. Compare rates of symptomatic influenza-virus infection across doses administered.

    Rate of symptomatic influenza-virus infection at each challenge dose group administered

    Measured: Study Day 1 up to Study Day 29

  2. Establish the safety profile of a live recombinant influenza strain RG-A/Texas/71/2017 (H3N2, Clade 3C3a) following challenge in healthy adult volunteers.

    Percent of unsolicited adverse events (AEs) reported from challenge to Study Day 29. Percent of solicited AEs, specifically Grade 3 or 4 adverse reactions (ARs), defined as signs and symptoms of influenza reported from challenge to Study Day 29. Percent of medically attended adverse events (MAAEs) reported from challenge to Study Day 57. Percent of serious adverse events (SAEs) reported from challenge to Study Day 85. Percent of influenza disease with serious complications (Adverse events of special interest (AESI)) reported from challenge to Study Day 29.

    Measured: Study Day 1 up to Study Day 85

  3. Assess the viral shedding

    Percent of participants within a challenge dose group with detected viral shedding in NPSs post-challenge from Study Day 2 onwards using culture and/or RT-qPCR.

    Measured: Study Day 1 up to Study Day 85

  4. Assess the peak viral load

    Magnitude of viral shedding post-challenge in each participant, defined as the peak viral load in NPSs from Study Day 2 onwards using RT-qPCR.

    Measured: Study Day 1 up to Study Day 85

  5. Measure the duration of the viral shedding

    Duration of viral shedding defined as the number of days from first positive RT-qPCR to last positive RT-qPCR where virus is detected in NPSs post-challenge from Study Day 2 onwards.

    Measured: Study Day 1 up to Study Day 85

  6. Determine the timing, magnitude, and nature of humoral immune responses (hemagglutinin inhibition (HAI) and microneutralization (MN) titers) post-challenge.

    Percent of participants with serological conversion defined as a minimum 4-fold rise in post-challenge serum antibodies (by HAI ) to influenza infection at Study Days 15, 29, 57, and 85 post-challenge compared to baseline.

    Measured: Study Day 1 up to Study Day 85

  7. Evaluate the association of culture and/or RT-qPCR-positivity with symptomatic influenza-virus infection.

    Correlation of virus culture and virus RT-qPCR with assigning symptomatic influenza-virus infection as the clinical outcome.

    Measured: Study Day 1 up to Study Day 8

  8. Explore the perspectives of Investigators and staff in fostering equitable, diverse, inclusive, and accessible (EDIA) participation in CHIM trials through a qualitative study using questionnaires

    Obtain and summarize viewpoints of Investigators and staff through questionnaires on participant equity, diversity, inclusion, and accessibility in CHIM trials.

    Measured: Study Day 1 up to Study Day 85

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted26 Dec 2025
  2. Study start1 Jun 2026
  3. Primary completion1 Jun 2027 (estimated)
  4. Study completion31 Jan 2028 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 1
Primary purpose
Other
Allocation
Non-randomised
Intervention model
Sequential
Masking
None (open label)
Enrolment
32 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07305207
Sponsor's protocol ID
CI2403
Other IDs
OCT-104219
Status last verified
Nov 2025
First submitted
27 Nov 2025
Last updated
27 Aug 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

A Phase 1 study testing Intranasal inoculation of RG-A/Texas/71/2017 (H3N2) influenza in each naris on Day 1 of the study. in people with Influenza (Healthy Volunteers), run by Dalhousie University at 1 site in Canada.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 27 inclusion and 41 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: looking for participants now, as of the sponsor's last update on 27 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Nick Bartlett (902-470-8141, nicholas.bartlett@iwk.nshealth.ca), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Symptomatic influenza-virus infection (time frame: Study Day 2 until Study Day 8). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT07305207.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Aug 2026.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in