Dose, Safety, and Pathogenicity of a New Influenza A H3N2 Challenge Strain

NCT06613737 | Completed Results

• 1 other identifier: HRD-vCS-006
• Study Type: interventional
• Target: 33
• Locations: 1 country
• Sites: 1

Brief 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)

Conditions

Influenza A H3N2

Keywords

Influenza; Flu; H3N2; Human Challenge Trial

Outcome Measures

Primary Outcomes (3)

• Occurrence of Adverse Events Related to the Viral Challenge

  Occurrence of adverse events (AEs) related to the viral challenge from viral challenge (Day 0) to the Day 28 follow-up visit.

  Day 0 to Day 28

• Occurrence of Serious Adverse Events Related to the Viral Challenge

  Occurrence of serious adverse events (SAEs) related to the viral challenge from viral challenge (Day 0) to the Day 28 follow-up visit.

  Day 0 to Day 28

• Induces Laboratory-confirmed Infection in ≥40% of Inoculated Participants

  Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR)-confirmed influenza infection, defined as 2 quantifiable (≥ lower limit of quantification \[LLOQ\]) qRT-PCR measurements (reported over 4 planned consecutive assessments within 48 hours), from Day 1 pm to planned discharge from quarantine (Day 8 am).

  Day 1 to Day 8

Secondary Outcomes (14)

• Incidence of Viral Culture-confirmed Influenza Infection.

  Day 1 to Day 8

• VL-AUC of Influenza Challenge Virus as Determined by qRT-PCR

  Day 1 to Day 8

• Peak Viral Load of Influenza Challenge Virus as Determined by qRT-PCR

  Day 1 to Day 8

• VL-AUC of Influenza Challenge Virus as Determined by Viral Culture

  Day 1 to Day 8

• Peak Viral Load of Influenza Challenge Virus as Determined by Viral Culture

  Day 1 to Day 8

Study Arms (3)

Dose 1

EXPERIMENTAL

Medium dose, expected to be approximately 10\^4.5 tissue culture infective dose 50% (TCID50)/mL (titer may be adjusted based on stock titer)

Other: Influenza A H3N2 virus dose arm 1

Dose 2

EXPERIMENTAL

High dose, expected to be approximately 10\^5.5 tissue culture infective dose 50% (TCID50)/mL (titer may be adjusted based on stock titer)

Other: Influenza A H3N2 virus dose arm 2

Dose 3

EXPERIMENTAL

Optional: TBD, depending on outcome of Part A

Other: Influenza A H3N2 virus dose arm 3

Interventions

Influenza A H3N2 virus dose arm 1 OTHER

Medium dose, approximately 10\^4.5 TCID50/mL

Dose 1

Influenza A H3N2 virus dose arm 2 OTHER

High dose, approximately 10\^5.5 TCID50/mL

Dose 2

Influenza A H3N2 virus dose arm 3 OTHER

TBD, depending on outcome of Part A

Dose 3

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• 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

You may not qualify if:

• 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.

Sponsors & Collaborators

• Hvivo: lead

Study Sites (1)

hVIVO Services Ltd, 40 Bank Street

London, E14 5NR, United Kingdom

Location

MeSH Terms

Conditions

Influenza, Human

Condition Hierarchy (Ancestors)

Respiratory Tract Infections; Infections; Orthomyxoviridae Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases

Results Point of Contact

• Title: Alex Mann
• Organization: hVIVO Services Ltd.

projectadmin@hvivo.com

+44 (0) 20 7756 1300

Study Officials

• Alexandre Lima, MD-PhD

  hVIVO Services Ltd.

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 23, 2024
• First Posted: September 26, 2024
• Study Start: September 11, 2024
• Primary Completion: March 10, 2025
• Study Completion: March 10, 2025
• Last Updated: April 23, 2026
• Results First Posted: April 23, 2026

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)