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Safety and Immunogenicity of IVX-A12 in Healthy Older Adults

Phase 1
Completed
Conditions
Healthy
Interventions
Biological: IVX-121
Biological: Placebo
Biological: IVX-241
Other: MF59®
Registration Number
NCT05664334
Lead Sponsor
Icosavax, Inc.
Brief Summary

The main purpose of this study is to evaluate the safety and immunogenicity of three dosage levels (low, medium, high) of the bivalent combination respiratory syncytial virus (RSV)/human metapneumovirus (hMPV) virus-like particle (VLP) candidate vaccine (IVX-A12), compared to placebo, when administered as a single-dose regimen in healthy older adults 60 to 75 years of age.

Detailed Description

The Phase 1 clinical trial of IVX-A12 is a randomized, observer-blinded, placebo-controlled, multi-center study designed to evaluate the safety and immunogenicity of multiple dosage levels of IVX-A12, with and without CSL Seqirus' proprietary adjuvant MF59®.

A total of up to 120 healthy older adults aged 60 to 75 years. Participants will be administered a single shot of IVX-A12, at one of three combination dosage levels below, or placebo. The overall duration of the study is up to 1 year (365 days).

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
140
Inclusion Criteria
  • Healthy male or non-pregnant female older adults 60 to 75 years of age at the time of first vaccination
  • Participants with stable well-controlled chronic conditions such as hypertension without clinical exacerbation of their underlying disease within the previous 12 months
  • Participants able to voluntarily give written informed consent and to comply with study procedures including follow-up to approximately 12 months after first dosing
  • Body mass index (BMI) 17 to 35 kilogram per square meter (kg/m^2), inclusive, at screening
  • Screening laboratory values must be within the laboratory reference ranges or deemed not clinically significant if within Grade 1 severity on the toxicity scale
Exclusion Criteria
  • Prior receipt of any investigational RSV or hMPV vaccine

  • Prior receipt of another investigational medicinal product (study drug, biologic, or device) not authorized for use in the United States and European Union within the past year

  • Laboratory-confirmed severe RSV or hMPV infection within the past year prior to enrollment

  • Currently enrolled or plan to participate in another clinical study with an investigational agent (including licensed or unlicensed vaccine, drug, biologic, device, blood product, or medication) to be received during the study period

  • Presence of high-risk comorbidities for severe RSV or hMPV disease (example, significant cardiopulmonary disease)

  • Older adults meeting frail elderly criteria (older persons with medical, nutritional, cognitive, emotional, or activity impairments, as defined by the study site)

  • Acute or chronic progressive, unstable or uncontrolled clinical conditions

  • Acute illness, with or without fever at the time of planned vaccination

  • History of hypersensitivity or serious adverse reactions to vaccines, such as anaphylaxis, Guillain-Barré, and angioedema, or any known allergies to any component of the IVX-121 and/or IVX-241 vaccine, or hypersensitivity to latex

  • Abnormal function of the immune system resulting from clinical conditions including human immunodeficiency virus, chronic administration of systemic corticosteroids (oral/intravenous/IM at a dose equivalent of greater than (>) 20 milligrams (mg) prednisone in a period of more than 14 days), or administration of immunosuppressive chemotherapy, biologics, or radiotherapy within the past 3 months before study randomization

  • Refusal to maintain contraceptive practices during the study, and (for women of childbearing potential) to be screened for pregnancy at specified times during the study

  • Receipt of licensed inactivated vaccines including influenza vaccine within 14 days prior to study vaccine administration on Study Day 0, or with live virus vaccines within 30 days of Day 0

    1. Receipt of licensed vaccines is permitted after completion of the study Day 28 visit.
    2. Receipt of licensed COVID-19 vaccines is permitted if dosing regimen completed within 21 days prior to study vaccine administration on Day 0 or after completion of the Day 28 visit.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
IVX-A12 Vaccine - Low Dosage LevelIVX-121Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 virus-like particles \[VLPs\]), administered intramuscularly (IM) once on Day 0.
IVX-A12 Vaccine + MF59® - Low Dosage LevelIVX-241Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 VLPs), administered IM once on Day 0.
IVX-A12 Vaccine + MF59® - Medium Dosage LevelMF59®Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 VLPs), administered IM once on Day 0.
IVX-A12 Vaccine - High Dosage LevelIVX-121Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 VLPs), administered IM once on Day 0.
IVX-A12 Vaccine - Low Dosage LevelIVX-241Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 virus-like particles \[VLPs\]), administered intramuscularly (IM) once on Day 0.
IVX-A12 Vaccine + MF59® - Low Dosage LevelIVX-121Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 VLPs), administered IM once on Day 0.
IVX-A12 Vaccine + MF59® - Low Dosage LevelMF59®Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 VLPs), administered IM once on Day 0.
IVX-A12 Vaccine - Medium Dosage LevelIVX-121Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 VLPs), administered IM once on Day 0.
IVX-A12 Vaccine + MF59® - Medium Dosage LevelIVX-121Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 VLPs), administered IM once on Day 0.
IVX-A12 Vaccine + MF59® - Medium Dosage LevelIVX-241Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 VLPs), administered IM once on Day 0.
IVX-A12 Vaccine - Medium Dosage LevelIVX-241Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 VLPs), administered IM once on Day 0.
PlaceboPlaceboParticipants will receive placebo, administered IM once on Day 0.
IVX-A12 Vaccine - High Dosage LevelIVX-241Participants will receive IVX-A12 vaccine (bivalent combination formulation containing IVX-121 and IVX-241 VLPs), administered IM once on Day 0.
Primary Outcome Measures
NameTimeMethod
Proportion of Participants With Solicited Local Reactions and Systemic AEsWithin 7 days After the Dose (From Day 0 to Day 6)
Proportion of Participants With Unsolicited AEsUp to 28 days After the Dose (From Day 0 to Day 28)
Proportion of Participants With RSV/A, RSV/B, hMPV/A and hMPV/B Neutralizing Antibodies (NAb)At Day 28
Proportion of Participants With RSV and hMPV Immunoglobulin G (IgG) Prefusion F Protein-specific Antibody TitersAt Day 28

RSV and hMPV IgG prefusion F protein-specific antibody titers as measured by enzyme-linked immunosorbent assays (ELISAs).

Secondary Outcome Measures
NameTimeMethod
Proportion of Participants With at Least One Serious Adverse Event (SAE), Medically-attended Adverse Events (MAAEs), AEs of Special Interest (AESIs) and AEs Leading to Study WithdrawalFrom Day 0 up to the end of study (Day 365)
Proportion of Participants With Clinically Significant Safety Laboratory AbnormalitiesAt screening, and after dosing, at Days 0, 7, and 28
Proportion of Participants With RSV/A, RSV/B, hMPV/A and hMPV/B Specific NAbs RSV and hMPV IgG Prefusion F Protein-specific Antibody Titers, RSV and hMPV IgG prefusion F protein-specific antibody titersAt Days 0, 7, 180, and 365
Geometric Fold Rise (GMFR) in Serum for Anti-RSV/A, RSV/B, hMPV/A and hMPV/B Specific NAbFrom Day 0 up to Day 180

Serum samples will be collected and the titers of serum neutralization antibodies will be assessed. GMFR is defined as the geometric mean of the ratio of concentration at specified timepoints after vaccination divided by concentration at baseline (Day 0).

GMFR in Serum for RSV and hMPV IgG Prefusion F Protein-specific Antibody TitersFrom Day 0 up to Day 180

GMFR is defined as the geometric mean of the ratio of concentration at specified timepoints after vaccination divided by concentration at baseline (Day 0).

Trial Locations

Locations (4)

PanAmerican Clinical Research

🇺🇸

Brownsville, Texas, United States

CenExcel ACMR

🇺🇸

Atlanta, Georgia, United States

CenExcel RCA

🇺🇸

Hollywood, Florida, United States

Meridien Clinical Research

🇺🇸

Omaha, Nebraska, United States

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