Phase 3 Adolescent Study for SARS-CoV-2 rS Variant Vaccines (COVID-19)

A Phase 3, Randomized, Double-Blinded Study to Evaluate the Safety and Immunogenicity of Omicron Subvariant and Bivalent SARS-CoV-2 rS Vaccines in Adolescents Previously Vaccinated With mRNA COVID-19 Vaccines

This study is a large-scale investigation (Phase 3) into a new booster shot designed specifically for teenagers. The booster targets a particular variant of COVID-19, Omicron XBB.1.5. The main focus is on safety: researchers want to see if this new booster is safe for teenagers who have already received two doses of the Pfizer or Moderna mRNA COVID-19 vaccines. To ensure a fair comparison, the study will use a double-blind approach. This means two groups of teenagers will receive booster shots, but neither the teenagers nor the researchers giving the shots will know beforehand which version of the booster each person gets. The study will also assess how well the body fights the virus after the booster shot.

Study Overview

• Status: Completed
• Conditions: COVID-19
• Intervention / Treatment: Biological: NVX-CoV2601 co-formulated Omicron XBB.1.5 SARS-CoV-2 rS vaccine; Biological: Prototype/XBB.1.5 Bivalent Vaccine (5 µg)

Detailed Description

This is a Phase 3, randomized, double-blinded study to evaluate the safety and immunogenicity of booster doses of Omicron subvariant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recombinant (r) spike (S) protein nanoparticle vaccines (SARS-CoV-2 rS) adjuvanted with Matrix-M™ adjuvant (NVX-CoV2601 [Omicron XBB.1.5]) and bivalent (NVX-CoV2373 [prototype] + NVX CoV2601) in previously vaccinated adolescent participants ≥ 12 to < 18 years of age.

Approximately 400 adolescents who have received a regimen of ≥ 2 doses of the Moderna and/or Pfizer-BioNTech monovalent and/or bivalent COVID-19 vaccines ≥ 90 days previously will be randomized 1:1 to Group A or Group B:

• Group A: 1 dose of NVX-CoV2601 (1 on Day 0)
• Group B: 1 dose of bivalent NVX-CoV2373 + NVX-CoV2601 (1 on Day 0) All participants will remain on study for immunogenicity and safety data collection through Day 180.

• Study Type: Interventional
• Enrollment (Actual): 400
• Phase: Phase 3

Contacts and Locations

Study Locations

• United States
  • Florida
    • Davie, Florida, United States, 33024
      • Alfa Medical Research
    • Jacksonville, Florida, United States, 32205
      • Westside Center For Clinical Research
    • Miami, Florida, United States, 33173
      • ITB Research
  • Idaho
    • Meridian, Idaho, United States, 83642
      • Velocity Clinical Research
  • Illinois
    • River Forest, Illinois, United States, 60305
      • DM Clinical Research - Chicago
  • Kansas
    • Lenexa, Kansas, United States, 66219
      • Johnson County Clinical Trials
    • Newton, Kansas, United States, 67114
      • Alliance for Multispecialty Research, LLC (AMR)
    • Wichita, Kansas, United States, 67207
      • AMR
  • Louisiana
    • Lafayette, Louisiana, United States, 70508
      • Velocity Clinical Research
  • New York
    • Vestal, New York, United States, 13850
      • Velocity Clinical Research
  • Ohio
    • Cincinnati, Ohio, United States, 45246
      • Velocity Clinical Research
  • Oklahoma
    • Tulsa, Oklahoma, United States, 74137
      • Tekton Research
  • Tennessee
    • Nashville, Tennessee, United States, 37203
      • Clinical Research Associates, Inc
  • Texas
    • Austin, Texas, United States, 78705
      • Benchmark Research
    • Corpus Christi, Texas, United States, 78404
      • South Texas Clinical Research
    • Houston, Texas, United States, 77065
      • DM Clinical Research
    • Katy, Texas, United States, 77450
      • Medical Colleagues of Texas, LLP
    • Plano, Texas, United States, 75093
      • Research Your Health
    • San Antonio, Texas, United States, 78244
      • Tekton Research
  • Utah
    • Pleasant View, Utah, United States, 84404
      • Mountain View CCT Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Adolescents ≥ 12 to < 18 years of age at screening
2. Participant and parent(s)/caregiver(s) or legally acceptable representative willing and able to give in-formed consent and assent, as required, 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 post-menopausal [defined as amenorrhea ≥ 12 consecutive months]) must agree to be heterosexually inactive from at least 28 days prior to enrollment and through the end of the study OR agree to consistently use a medically acceptable method of contraception listed below from ≥ 28 days prior to enrollment and through the end of the study.
4. Is medically stable, as determined by the investigator (based on review of health status, vital signs [to include body temperature], medical history, and targeted physical examination [to include body weight]). Vital signs must be within medically acceptable ranges prior to the vaccination.
5. Agrees to not participate in any other SARS-CoV-2 prevention or treatment trials for the duration of the study.
6. Have previously received ≥ 2 doses of the Moderna and/or Pfizer-BioNTech monovalent and/or bivalent COVID-19 vaccines with the last dose having been given ≥ 90 days previously prior to study vaccination.

Exclusion Criteria:

1. Received COVID-19 vaccines other than Moderna and/or Pfizer-BioNTech in the past, inclusive of clinical trial COVID-19 vaccines.
2. Participation in research involving receipt of investigational products (drug/biologic/device) within 90 days prior to study vaccination.
3. Received influenza vaccination within 14 days prior to study vaccination.
4. Received any vaccine ≤ 45 days prior to study vaccination, except for rabies, human papilloma virus (HPV), tetanus-diphtheria (Td), tetanus, diphtheria, and pertussis (TDaP/DTap), hepatitis B virus (HBV), and meningococcal vaccines which may be given as medically indicated.
5. Any known allergies to products contained in the investigational product.
6. Any history of anaphylaxis to any prior vaccine.
7. Autoimmune or immunodeficiency disease/condition (iatrogenic or congenital) requiring ongoing immunomodulatory therapy.

8. Chronic administration (defined as > 14 continuous days) of immunosuppressant, systemic glucocorticoids, or other immune-modifying drugs within 90 days prior to study vaccination.

   An immunosuppressant dose of glucocorticoid is defined as a systemic dose ≥ 10 mg of prednisone per day or equivalent. The use of topical or intranasal glucocorticoids is permitted. Topical tacrolimus and ocular cyclosporin are permitted.

9. 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.
10. Active cancer (malignancy) on therapy within 3 years prior to study vaccination (with the exception of adequately treated non-melanomatous skin carcinoma or lentigo maligna and uterine cervical carcinoma in situ without evidence of disease, at the discretion of the investigator).
11. Participants who are breastfeeding, pregnant, or who plan to become pregnant prior to the end of study.
12. Suspected or known history of alcohol abuse or drug addiction within 2 years prior to the study vaccine dose that, in the opinion of the investigator, might interfere with protocol compliance.
13. 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 study vaccine or interpretation of study results (including neurologic or psychiatric conditions likely to impair the quality of safety reporting).
14. 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).
15. Participants with a history of myocarditis or pericarditis.
16. Respiratory symptoms in the past 3 days (ie, cough, sore throat, difficulty breathing).
17. Temperature of > 38°C within 24 hours of planned study vaccination (site measured or participant measured).
18. Blood pressure of ≥ 160/100 mmHg.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Group-A NVX-CoV2601; The Monovalent NVX-CoV2601 of 5 μg of antigen with 50 μg of Matrix-M adjuvant	Biological: NVX-CoV2601 co-formulated Omicron XBB.1.5 SARS-CoV-2 rS vaccine; Coformulated Omicron XBB.1.5 SARS-CoV-2 rS vaccine with Matrix-M adjuvant: supplied as a solution for preparation for injection, at a concentration of 10 µg antigen and 100 µg adjuvant per mL. All injections will be administered in a 0.5 mL injection volume at a dose of 5 µg antigen with 50 µg Matrix-M adjuvant.; Other Names: NVX-CoV2601
Active Comparator: Group-B Bivalent NVX CoV2373 + NVX CoV2601; The Bivalent NVX CoV2373 + NVX CoV2601 of 5 μg of each antigen with a total of 50 μg of Matrix-M adjuvant	Biological: Prototype/XBB.1.5 Bivalent Vaccine (5 µg); A site-mixed bivalent vaccine prepared by combining 0.25 mL of NVX-CoV2373 and 0.25 mL NVX-CoV2601. All injections will be administered in a 0.5 mL injection volume at a dose of 5 µg total antigen (2.5 µg prototype antigen + 2.5 µg Omicron XBB.1.5 antigen) with 50 µg Matrix-M adjuvant.; Other Names: Omicron XBB.1.5 (sub-variant)SARS-CoV-2 rS /Matrix-M Adjuvant

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Participants With Solicited Local and Systemic AEs for 7 Days Following Vaccination	Participants with solicited local and systemic adverse events (AEs) To assess the overall safety of 1 heterologous booster dose of NVX CoV2601 and the bivalent vaccine (NVX CoV2373 + NVX-CoV2601) for 7 days following vaccination	Day 7
Participants With Unsolicited AEs Through 28 Days After Vaccination	Participants with unsolicited AEs to assess the overall safety of 1 heterologous booster dose of NVX CoV2601 and the bivalent vaccine (NVX CoV2373 + NVX-CoV2601) through 28 days after vaccination.	Day 28
Participants With (MAAEs) Attributed to Study Vaccine, (AESIs) (PIMMCs), Myocarditis and/or Pericarditis, and Complications Specific to COVID-19), and Serious Adverse Events (SAEs)	Participants with medically attended adverse events (MAAEs) attributed to study vaccine, adverse events of special interest (AESIs) (predefined list including potential immune-mediated medical conditions (PIMMCs), myocarditis and/or pericarditis, and complications specific to COVID-19), and serious adverse events (SAEs) o assess the overall safety of 1 heterologous booster dose of NVX CoV2601 and the bivalent vaccine (NVX CoV2373 + NVX-CoV2601)through day 180 or end of study (EOS).	Day 180
Immunogenicity Index- Neutralizing Antibody (NAb) Expressed as Geometric Mean Titers (GMTs) to the Omicron XBB.1.5 Strain.	The neutralizing antibody (NAb) response induced by NVX CoV2601 and the bivalent vaccine (NVX CoV2373 + NVX-CoV2601) against the Omicron XBB.1.5 strain assessed at Day 28 following initial study vaccination.	Day 0 and Day 28
Immunogenicity Index- The Neutralizing Antibody (NAb) Expressed as Geometric Mean Fold Rise (GMFR) to the Omicron XBB.1.5 Strain.	the neutralizing antibody (NAb) response induced by NVX CoV2601 and the bivalent vaccine (NVX CoV2373 + NVX-CoV2601) against the Omicron XBB.1.5 strain, assessed at Day 28	Day 28

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Neutralizing Antibody (NAb) Expressed as Geometric Mean Titers (GMTs) to the Omicron XBB.1.5 Strain.	the neutralizing antibody NAb response induced by NVX CoV2601 and the bivalent vaccine (NVX CoV2373 + NVX-CoV2601) against the Omicron XBB.1.5 strain over time. at relevant time points.	Day 0 to Day 180
Neutralizing Antibody (NAb) Expressed as Geometric Mean Fold Rise (GMFR) to the Omicron XBB.1.5 Strain.	The neutralizing antibody NAb response induced by NVX CoV2601 and the bivalent vaccine (NVX CoV2373 + NVX-CoV2601) against the Omicron XBB.1.5 strain over time. at relevant time points.	Day 28 to Day 180
IgG Geometric Mean ELISA (Enzyme-linked Immunosorbent Assay) Units (GMEUs) to the Omicron XBB.1.5 S Protein.	The immunoglobulin G (IgG) antibody levels induced by NVX CoV2601 and the bivalent vaccine (NVX CoV2373 + NVX-CoV2601) against the Omicron XBB.1.5 strain over time.at relevant time points.	Day 0 to Day 180
NAb(Neutralizing Antibody Titers) Levels Are Measured to the Ancestral (Wuhan) Strain .	The NAb antibody responses induced by NVX CoV2601 and the bivalent vaccine (NVX CoV2373 + NVX-CoV2601) against the ancestral (Wuhan) strain at relevant time points .	Day 0 to 180
Serum IgG GMEUs Levels Are Measured to the Ancestral (Wuhan) Strain .	The serum IgG antibody responses induced by NVX CoV2601 and the bivalent vaccine (NVX CoV2373 + NVX-CoV2601) against the ancestral (Wuhan) strain at relevant time points.	Day 0 to Day 180

Collaborators and Investigators

• Sponsor: Novavax
• Investigators: Study Director: Clinical Development, Novavax

Study record dates

Study Major Dates

• Study Start (Actual): August 16, 2023
• Primary Completion (Actual): April 1, 2024
• Study Completion (Actual): September 30, 2024

Study Registration Dates

• First Submitted: July 31, 2023
• First Submitted That Met QC Criteria: July 31, 2023
• First Posted (Actual): August 2, 2023

Study Record Updates

• Last Update Posted (Actual): July 15, 2025
• Last Update Submitted That Met QC Criteria: June 25, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Respiratory Tract Infections; Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Lung Diseases; Pneumonia, Viral; Pneumonia; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; COVID-19; Immunologic Factors; Physiological Effects of Drugs; Vaccines
• Other Study ID Numbers: 2019nCoV-314

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No