Skip to main content
OpenTrials
Completed

NCT Number: NCT06028347

Safety, Reactogenicity, and Immunogenicity Study of a Self-Amplifying MRNA Influenza Vaccine in Healthy Adults

This is a Phase 1, first-in-human, randomized, placebo-controlled, observer blind study. The effect of two doses of an investigational vaccine on safety, reactogenicity, kinetics and magnitude of the post-vaccination antibody response will be evaluated at different timepoints as compared to placebo in healthy adults.

Approximately 96 evaluable subjects will be enrolled in this study; n=72 receiving investigational vaccine and n=24 receiving placebo.

The study has a screening period (Day -28 to Day -1), a treatment period (Day 1 to Day 43) and a follow-up period (Day 44 to Day 202).

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Influenza, Human Infections Orthomyxoviridae Infections RNA Virus Infections Respiratory Tract Diseases Respiratory Tract Infections Virus Diseases

Age range

18 year–85 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 1

Primary location

Nucleus Network Brisbane Clinic, Brisbane, Queensland, Australia

Loading trial locations.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Individuals 18 to 49 years of age OR 65 to 85 years of age, inclusive on the day of informed consent.
  • Individuals with body mass index (BMI) between 18 and 32 kg/m2, inclusive, at screening .
  • Individuals who can comply with study procedures including follow-up .

Exclusion criteria

  • Female participants of childbearing potential who are pregnant, lactating, or who have not adhered to a specified set of highly effective contraceptive methods from at least 30 days prior to informed consent and who do not plan to do so for the duration of the study.
  • Male participants who have not adhered to using barrier contraception such as a condom during at least 60 days after each vaccination, to prevent semen transfer to their sexual partners and prevent pregnancy of a female partner.
  • Progressive, unstable, or uncontrolled clinical conditions
  • Known hypersensitivity or allergy to any study vaccine component
  • Known history of Guillain-Barré syndrome or other demyelinating disease
  • Condition representing a contraindication to vaccination or blood draw
  • Abnormal function of immune system due to clinical condition, medications, or radiotherapy.
  • Receipt or planning to receive blood products, non-study vaccine, influenza vaccine, mRNA-platform vaccine within different timeframes; previous or from study vaccination.
  • Baseline abnormal clinically significant ECG, laboratory safety parameters or vital signs.
  • Plan to donate blood products (other than for this study), sperm, ova, tissues, or organs up to 60 days following the last vaccination.

Treatment and study plan

sa-mRNA vaccine Dose 1

Biological

self-amplifying mRNA vaccine

sa-mRNA vaccine Dose 2

Biological

self-amplifying mRNA vaccine

sa-mRNA vaccine Dose 3

Biological

self-amplifying mRNA vaccine

Placebo

Biological

Saline for injection

Primary outcomes

  1. Number and percentage of subjects with clinically significant abnormal vital signs and/or acute reactions

    Time frame: up to 60 minutes or within 6 hours post vaccination

  2. Number and percentage of subjects reporting reactogenicity: Solicited local and systemic AEs

    Time frame: Day 1 to Day 14 of each post vaccination period

  3. Number and percentage of subjects reporting unsolicited AEs

    Time frame: Day 1 to Day 43

  4. Number and percentage of subjects reporting AEs leading to study withdrawal, Adverse Events of Special Interest (AESIs), medically attended AEs (MAAEs), and serious adverse events (SAEs).

    Time frame: Day 1 to Day 202

  5. Number and percentage of subjects with Grade 3 or greater abnormal clinically significant hematology and chemistry laboratory values

    Time frame: Day 3 to Day 43

  6. Number and percentage of subjects with grading shifts in hematology and chemistry laboratory assessments

    Time frame: Day 3 to Day 43

  7. Serum antibody titer against the HA glycoprotein in terms of GMT, GMFI, and GMT ratio measured via HI assay

    Time frame: Day 1, Day 22, Day 43

  8. Number and percentage of subjects with HAI titer ≥1:10 and <1:10 (lower limit of quantification [LLOQ])

    Time frame: Day 1, Day 22, Day 43

  9. Number and percentage of subjects with HAI titer ≥1:40, ≥1:80, ≥1:160 and ≥1:320

    Time frame: Day 1, Day 22, Day 43

  10. Seroconversion rate (SCR) by HAI assay

    Time frame: Day 1, Day 22, Day 43

    SCR defined as the percentage of subjects with either a prevaccination HAI titer <1:10 and a post-vaccination HAI titer ≥1:40, or a prevaccination HAI titer ≥1:10 and a ≥4-fold increase in post-vaccination

Secondary outcomes

  1. Serum antibody titer against the HA glycoprotein in terms of GMT, GMFI, and GMT ratio measured via HI assay

    Time frame: Day 1, Day 202

  2. Number and percentage of subjects with ≥4-fold increase in post-vaccination HAI titer

    Time frame: Day 1, Day 202

  3. Number and percentage of subjects with HAI titer ≥1:10 and <1:10 (LLOQ)

    Time frame: Day 202

  4. Number and percentage of subjects with HAI titer ≥1:40, ≥1:80, ≥1:160 and ≥1:320

    Time frame: Day 202

  5. Seroconversion rate (SCR) by HAI assay

    Time frame: Day 1, Day 202

  6. Serum antibody titer against the NA glycoprotein in terms of GMT, GMFI, and GMT ratio measured via ELLA assay

    Time frame: Day 1, Day 22, Day 43, Day 202

  7. Number and percentage of subjects with ≥4-fold increase in post-vaccination ELLA titer

    Time frame: Day 1, Day 22, Day 43, Day 202

Sponsors and collaborators

Lead sponsor

Seqirus

Industry

Registry information

Official study title

Phase 1, Randomized, Placebo-Controlled, Observer Blind Study to Evaluate the Safety, Reactogenicity and Immunogenicity of an Investigational Self-Amplifying MRNA Influenza Vaccine in Healthy Adults

Important dates

Study start
2023
Primary completion
2024
Study completion
2024
First posted
Sep 8, 2023
Registry last updated
Nov 27, 2024

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.