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Phase 3 Study of Novavax Vaccine(s) as Booster Dose After mRNA Vaccines

Phase 3
Completed
Conditions
COVID-19
Interventions
Biological: NVX-CoV2373
Biological: SARS-CoV-2 rS antigen/Matrix-M Adjuvant
Registration Number
NCT05875701
Lead Sponsor
Novavax
Brief Summary

This is an open-label Phase 3 study evaluating the immunogenicity and safety of Novavax vaccine(s) with Matrix-M™ adjuvant (ancestral strain NVX-CoV2373 and an alternative strain and/or multivalent Novavax vaccine) as booster doses following a series of primary and booster doses of authorized/approved mRNA vaccines followed by a single booster dose of NVX-CoV2373 in the Novavax 2019nCoV-307 study (NCT05463068).

Detailed Description

This Phase 3 study investigates the immunogenicity and safety of Novavax's NVX-CoV2373 vaccine (including its Matrix-M adjuvant) as an additional booster dose for adults aged 18 to 49. Participants must have already received both their primary mRNA vaccine series and at least one booster dose of the same type. All participants were previously enrolled in Study 307 (NCT05463068), where they received either their primary mRNA vaccines with or without an additional mRNA booster, followed by a single NVX-CoV2373 booster.

The study involves up to 300 volunteers who will receive a single dose of the Novavax vaccine (5 micrograms of recombinant spike protein antigen and 50 micrograms of Matrix-M adjuvant) on Day 1.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
300
Inclusion Criteria

To be included in this study, each individual must satisfy all the following criteria:

  1. Adults 18 to 49 years (inclusive) of age at the time of vaccination in Study 307 who received two or three doses of mRNA prior to enrollment in Study 307, then one dose of ancestral strain NVX-CoV2373 in Study 307.
  2. Willing and able to give informed consent prior to study enrollment and to comply with study procedures.
  3. Participants of childbearing potential (defined as any participant who has experienced menarche and who is NOT surgically sterile [ie, hysterectomy, bilateral tubal ligation, or bilateral oophorectomy] or postmenopausal [defined as amenorrhea at least 12 consecutive months]) must agree to be heterosexually inactive from at least 28 days prior to enrollment and through the end of study (EOS) visit OR agree to consistently use a medically acceptable method of contraception from at least 28 days prior to enrollment and through the EOS visit.
  4. Is medically stable, as determined by the investigator (based on review of health status, vital signs [to include body temperature], medical history, and physical examination [to include body weight]). Vital signs must be within medically acceptable ranges prior to the study vaccination.
  5. Agree to not participate in any other SARS-CoV-2 prevention or treatment trials for the duration of the study. Note: For participants who become hospitalized with COVID-19, participation in investigational treatment studies is permitted.
  6. Documented receipt of COVID-19 vaccines. The most recent dose of NVX-CoV2373 must have been administered at least 180 days prior to vaccination in this study.
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Exclusion Criteria

Participants meeting any of the following criteria will be excluded from the study.

  1. Received any additional COVID-19 vaccine booster after the Day 1 dose of NVX-CoV2373 administered during participation in Study 307.
  2. History of laboratory-confirmed (by polymerase chain reaction [PCR] or rapid antigen test) COVID-19 infection ≤ 4 months prior to Day 1.
  3. Current participation in research involving receipt of an investigational product (drug/biologic/device).
  4. Any known allergies or history of anaphylaxis to the active substance or any of the other ingredients contained in the investigational product.
  5. Any autoimmune or immunodeficiency disease/condition (iatrogenic or congenital) or therapy that causes clinically significant immunosuppression.
  6. Received any vaccine ≤ 90 days prior to study vaccination, except for influenza vaccine which may be received > 4 days prior to study vaccine, or rabies vaccine, which may be received at any time if medically indicated.
  7. Received immunoglobulin, blood-derived products, or immunosuppressant drugs within 90 days prior to study vaccination, except for rabies immunoglobulin which may be given if medically indicated.
  8. Active cancer (malignancy) on chemotherapy that is judged to cause significant immunocompromise within 1 year prior to first study vaccination (with the exception of malignancy cured via excision, at the discretion of the investigator).
  9. Participants who are breastfeeding, pregnant, or who plan to become pregnant prior to the EOS visit.
  10. Suspected or known history of alcohol abuse or drug addiction within 3 months prior to the study vaccine dose that, in the opinion of the investigator, might interfere with protocol compliance.
  11. Any other condition that, in the opinion of the investigator, would pose a health risk to the participant if enrolled or could interfere with evaluation of the trial vaccine or interpretation of study results (including neurologic or psychiatric conditions likely to impair the quality of safety reporting).
  12. Study team member or immediate family member of any study team member (inclusive of Sponsor, clinical research organization [CRO], and study site personnel involved in the conduct or planning of the study).
  13. Participants with a history of myocarditis or pericarditis.
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Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
NVX CoV2373 (Ancestral strain)NVX-CoV23731dose of NVX-COV2373 on Day 1
Updated COVID-19 VaccineSARS-CoV-2 rS antigen/Matrix-M Adjuvant1dose of updated COVID-19 vaccine on Day 1
Primary Outcome Measures
NameTimeMethod
Neutralizing Antibody (Nab) responses expressed as Geometric Mean TitersDay 29

Neutralizing Antibody responses GMTs to ancestral strain Novavax vaccine (NVX-CoV2373) at Day 29

Secondary Outcome Measures
NameTimeMethod
Human Angiotensin-Converting Enzyme 2 (hACE2) Receptor Binding Inhibition Assay Expressed as Seroresponse (SPR)Day 29

hACE2 Receptor Binding Inhibition Assay the SARS-CoV-2 ancestral strain spike protein expressed as SPR at Day 29

Incidence and Severity of Medically Attended Adverse Events (MAAEs)Day 1 to Day 180

Incidence, duration, severity and of MAAEs through Day 180 after the vaccine dose.

Incidence and Severity of Adverse Events Special Interests (AESIs)Day 1 to Day 180

Incidence, duration, severity and of AESIs (including myocarditis and/or pericarditis) through Day 180 after the vaccine dose.

Nab Antibody responses expressed as Seroconversion Rate (SCR)Day 29

Proportion of participants who achieve seroconversion (≥ 4-fold increase from baseline) in neutralization antibody titers to the ancestral strain Novavax Vaccine (NVX-CoV2373) at Day 29

Incidence and Severity of Solicited Adverse Events (AEs)Day 7

Incidence, duration, and severity of solicited adverse reactions in the 7 days following study vaccination.

Incidence and Relationship of Serious Adverse Events (SAEs)Day 1 to Day 180

Incidence and Relationship of SAEs through Day 180 after the vaccine dose

Serum IgG Antibody levels expressed as SCRDay 29

Proportion of participants who achieve seroconversion (≥ 4-fold increase from baseline) in IgG concentration to the ancestral strain spike protein at Day 29

Neutralizing Antibody responses (Post-Booster) expressed as GMTDay to Day 181

Post Booster Neutralizing Antibody responses GMTs compared with post-first booster results from Study 307

Serum IgG Antibody Levels (Post-Booster) Expressed as GMEUDay to Day 181

Post Booster Serum IgG antibody levels expressed GMEUs compared with post-first booster results from Study 307

Serum Immunoglobulin G (IgG) Antibody Levels Expressed as GMEUDay 29

IgG antibody levels to the SARS-CoV-2 ancestral strain spike protein as detected by enzyme-linked immunosorbent assay (ELISA) expressed as (GMEU/mL) at Day 29

Trial Locations

Locations (3)

Benchmark Research

🇺🇸

Fort Worth, Texas, United States

Tekton Research

🇺🇸

San Antonio, Texas, United States

Research Your Health

🇺🇸

Plano, Texas, United States

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