N/A
N=33
Dose, Safety, and Pathogenicity of a New Influenza A H3N2 Challenge Strain
Influenza A H3N2
Bottom Line
View on ClinicalTrials.gov: NCT06613737 ↗Enrolled (actual)
33
Serious AEs
0.0%
Results posted
Apr 2026
Primary outcome: Primary: Occurrence of Adverse Events Related to the Viral Challenge — 0; 0; 1; 6 Occurrence of adverse events
Study Design & Population
- Study type
- Interventional
- Phase
- N/A
- Interventions
- Influenza A H3N2 virus dose arm 1 (Other); Influenza A H3N2 virus dose arm 2 (Other); Influenza A H3N2 virus dose arm 3 (Other)
- Age
- Adult · 18+ yrs
- Sex
- All
- Sponsor
- Hvivo
- Primary completion
- Mar 2025
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Occurrence of Adverse Events Related to the Viral Challenge |
0; 0; 1; 6 | — |
| PRIMARY Occurrence of Serious Adverse Events Related to the Viral Challenge |
0; 0; 0; 0 | — |
| PRIMARY Induces Laboratory-confirmed Infection in ≥40% of Inoculated Participants |
3; 3; 3; 12 | — |
| SECONDARY Incidence of Viral Culture-confirmed Influenza Infection. |
2; 2; 1; 10 | — |
| SECONDARY VL-AUC of Influenza Challenge Virus as Determined by qRT-PCR |
20.03; 18.40; 14.61; 22.21; 10.10 | — |
| SECONDARY Peak Viral Load of Influenza Challenge Virus as Determined by qRT-PCR |
4.69; 4.75; 4.26; 5.52; 3.86 | — |
| SECONDARY VL-AUC of Influenza Challenge Virus as Determined by Viral Culture |
9.72; 6.05; 6.19; 7.50; 5.36 | — |
| SECONDARY Peak Viral Load of Influenza Challenge Virus as Determined by Viral Culture |
2.35; 2.20; 1.52; 2.66; 1.50 | — |
| SECONDARY Area Under the Total Clinical Symptoms Score-time Curve (TSS-AUC) |
5.88; 10.91; 3.05; 10.23 | — |
| SECONDARY Peak Total Symptoms Diary Card Score |
3.20; 5.40; 2.75; 4.05 | — |
| SECONDARY Peak Daily Symptoms Diary Card Score |
0.80; 0.40; 1.25; 0.95; 0.40; 2.80 | — |
| SECONDARY Laboratory-confirmed Febrile Influenza Infection |
1; 1; 0; 2 | — |
| SECONDARY qRT-PCR-confirmed Influenza-like Illness (Centers for Disease and Control [CDC]) |
1; 0; 0; 2 | — |
| SECONDARY qRT-PCR-confirmed Influenza-like Illness (World Health Organization [WHO]) |
1; 0; 0; 1 | — |
| SECONDARY Laboratory-confirmed Moderately Severe Symptomatic Influenza Infection |
1; 3; 0; 7 | — |
| SECONDARY Laboratory-confirmed Symptomatic Influenza Infection |
3; 3; 2; 9 | — |
| SECONDARY Viral Culture Laboratory-confirmed Moderately Severe Symptomatic Influenza Infection |
1; 2; 0; 7 | — |
Summary
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
In Part A, up to 40 participants will be randomly allocated to one of two groups to be given one of two virus doses (Virus Dose 1 or Virus Dose 2).
Based on the outcome of Part A, participants in Part B, may be given Virus Dose 1, Virus Dose 2, or another virus dose (e.g., Virus Dose 3)
Eligibility 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
Data sourced from ClinicalTrials.gov (NCT06613737). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.