ClinicalTrials.gg
RecruitingNCT06254820Updated Feb 12, 2024

Dose, Safety, and Pathogenicity of a New Influenza B Strain

A Phase 2 interventional study of influenza B/Connecticut/1/21 virus part a dose arm 1 and influenza B/Connecticut/1/21 virus part a dose arm 2 in Influenza B, sponsored by Hvivo. Recruiting at 1 site in United Kingdom. Open to participants aged 18 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-02-12.

Sponsored by Hvivo · Phase 2, Interventional, and Other

From the registry’s dates

  • Primary completion was expected by Feb 2024, 2 years 9 months ago, but the record still lists the study as recruiting.
  • Started Oct 2023; still recruiting 3 years 1 month later.
Phase
Phase 2
Study type
Interventional
Enrollment
60
Allocation
Randomized
Ages
18 Years to 55 Years
Sex
All
01

Study summary

This is an exploratory study of an influenza B challenge strain to determine the optimum infectious titer of challenge agent in healthy participants 18 to 55 years of age.

Read the detailed description

This is an exploratory study of an influenza B challenge strain to determine the optimum safe infectious titer of challenge agent in healthy participants 18 to 55 years of age. A total of up to 80 participants may be given influenza B challenge virus. The study will be conducted in 2 parts. In Part A, 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).

Each participant will remain in the study for approximately 1 month from admission to quarantine to the last clinic visit.

The study is divided into three phases:

  1. Screening phase: Screening will occur between Day -90 to Day -2/-1. has been signed by the participant.
  2. Quarantine phase: Participants will stay in the quarantine unit for approximately 11 days (from Day -2/-1 to Day 8).

    One or two days prior to the day of inoculation with the challenge virus, participants will be admitted to quarantine where their eligibility will be reassessed. If participants remain eligible for the study, they will receive the challenge virus on Day 0. Participants will undergo a range of clinical assessments and safety monitoring for the entirety of their stay in quarantine. Participants will be discharged from the quarantine unit on Day 8 (or may remain longer at the principal investigator's discretion).

  3. Outpatient phase: Final follow-up visit 28 days (±3 days) after the day they receive the virus. Their symptoms will be reassessed, and a complete safety examination performed.
02

Conditions studied

  • Influenza B

Browse trials for

Keywords

  • Influenza
  • Flu
  • Human Challenge Trials
  • Flu B
03

In context

Influenza, Human

2,356 studies on the registry are indexed under Influenza, Human; 184 are open to participants now.

This study's planned enrollment of 60 is below the median of 227 across 1,957 interventional studies indexed under Influenza, Human.

Browse Influenza, Human studies →

Lead sponsor

Hvivo is the lead sponsor of 13 studies on the registry; 2 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 55 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

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

Exclusion criteria

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 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.
  • Lifetime history of anaphylaxis and/or a lifetime history of severe allergic reaction.
  • Venous access deemed inadequate for the phlebotomy and cannulation demands of the study.
  • Significant abnormality of the nose, epistaxis, nasal or sinus surgery.
  • Recent vaccinations or intention to receive vaccination before the final 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 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 or recent history or presence of alcohol addiction
  • A (FEV1) \<80%.
  • Positive , virus, or virus test.
  • Presence of fever, defined as participant presenting with a temperature reading of ≥37.9C 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
Terms in these criteria, in plain language(9)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

FEV1

From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

Hepatitis B tests

Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.

Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

05

Study design

Phase
Phase 2
Primary purpose
Other
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Investigator)
Enrollment
60 participants (estimated)

Study arms

  • Experimental
    Part A Dose Arm 1

    Medium dose, expected to be approximately 10\^6 tissue culture infective dose 50% (TCID50)/mL (titer may be adjusted based on stock titer)

    Biological: influenza B/Connecticut/1/21 virus part a dose arm 1

  • Experimental
    Part A Dose Arm 2

    Dose Arm 2: High dose, expected to be approximately 10\^7 TCID50/ mL (titer may be adjusted based on stock titer)

    Biological: influenza B/Connecticut/1/21 virus part a dose arm 2

  • Experimental
    Part B Dose Extension:

    Extension of one of the Part A dose arms; which one is to be determined (TBD) depending on outcome of Part A, AND/OR

    Biological: influenza B/Connecticut/1/21 virus part b dose 1

  • Experimental
    Part B Dose Arm 3

    Addition of a 3rd dose, TBD depending on outcome of Part A

    Biological: influenza B/Connecticut/1/21 virus part b dose 2

Interventions

  • Biologicalinfluenza B/Connecticut/1/21 virus part a dose arm 1

    Medium dose, expected to be approximately 10\^6 tissue culture infective dose 50% (TCID50)/mL (titer may be adjusted based on stock titer)

  • Biologicalinfluenza B/Connecticut/1/21 virus part a dose arm 2

    High dose, expected to be approximately 10\^7 TCID50/ mL (titer may be adjusted based on stock titer)

  • Biologicalinfluenza B/Connecticut/1/21 virus part b dose 1

    Extension of one of the Part A dose arms; which one is to be determined (TBD) depending on outcome of Part A, AND/OR Dose Arm 3

  • Biologicalinfluenza B/Connecticut/1/21 virus part b dose 2

    Addition of a 3rd dose, TBD depending on outcome of Part A

06

What researchers measure

Primary outcomes

  1. Occurrence of AEs and SAEs

    Measuring the occurrence of AEs and SAEs as assessed by CTCAE v4.0 during the first 28 days of treatment in \>/=40% of participants with laboratory confirmed infection.

    Time frame: Day 0 - Day 28

07

Study locations

1 of 1 sites recruiting
  • QMB
    London, E1 2AX, United Kingdom
    Recruiting
    • Victoria Parker, MBBS · Contactprojectadmin@hvivo.com · +442077561300
    • Victoria Parker, MBBS · Principal investigator
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Feb 12, 2024, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06254820
Lead sponsor
Hvivo
Collaborators
Pfizer
Responsible party
Sponsor
First posted
Feb 12, 2024
Start date
Oct 3, 2023
Primary completion
Feb 2, 2024 (estimated)
Completion
Feb 8, 2024 (estimated)
Last update
Feb 12, 2024

Study contacts

Alex Mann
Contact
projectadmin@hvivo.com
+44(0)207 756 1300
Victoria Parker, MBBS
Contact
projectadmin@hvivo.com
+44(0)207 756 1300
Victoria Parker, MBBS
principal investigator · hVIVO Services Ltd.

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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