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AzTrials

COVID-19Phase 2/3COVID-19NCT05468736

Study to Evaluate Safety and Immunogenicity of COVID-19 Vaccine in Children 6 Months to < 12 Years

A Phase 2/3 study testing SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period) in people with COVID-19, run by Novavax at 94 sites in 10 countries.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

This is a Phase 2/3 randomized, observer-blinded, placebo-controlled, age de-escalation trial to evaluate the safety and immunogenicity of 2 primary doses of SARS-CoV-2 rS with Matrix-M™ adjuvant (NVX-CoV2373) given 21 days apart and NVX CoV2373 or a variant-based vaccine given as a booster dose or at crossover in… Read more about this study

Who is it for?
Ages 6 months to 11 yearsHealthy volunteers can take part
Conditions the study is for
COVID-19
What is being tested?
SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period)
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
3,600 participants
Where
94 sitesin 10 countries
Study dates
22 Jul 2022to 25 Oct 2025
Phase
Phase 2/3
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 6 months to 11 years
  • All sexes
  • Healthy volunteers accepted
  • Child

Who may be able to join

  • To be included in this study, each individual must satisfy all of the following criteria:
  • Pediatric participants 6 months to < 12 years of age at randomization, determined to be healthy or medically stable 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 the normal range prior to the first vaccination, according to the child's age, sex, weight, and height/length.
  • For children from 6 months to < 12 months of age: born at full-term (≥ 37 weeks gestation) with a minimum birth weight of 2.5 kilograms (kg).
  • Participant and parent(s)/caregiver(s) or legally acceptable representative willing and able to give informed consent and assent, as required, prior to study enrollment and to comply with study procedures.
  • 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]) must agree to be heterosexually inactive from at least 28 days prior to enrollment and through 3 months after the last vaccination OR agree to consistently use a highly effective contraception method from at least 28 days prior to enrollment and through 3 months after the last vaccination.
  • Agree not to participate in another SARS-CoV-2 prevention trial for the duration of the study.

Who cannot join

  • If an individual meets any of the following criteria, he or she is ineligible for this study:
  • Any acute illness/infection (according to investigator judgment) on the day of vaccination or febrile illness (temperature ≥ 100.4°F [≥ 38.0°C]). A prospective subject should not be included in the study until the condition has resolved or the febrile event has subsided.
  • Unstable acute or chronic illness. Criteria for unstable medical conditions include:
  • Substantive changes in chronic prescribed medication (change in class or significant change in dose) in the past 2 months.
  • Currently undergoing workup of undiagnosed illness that could lead to a diagnosis of a new condition.
  • NOTE: Well-controlled human immunodeficiency virus [HIV] infection with undetectable HIV ribonucleic acid [RNA < 50 copies/mL] and CD4 count > 200 cells/µL for at least 1 year, documented within the last 6 months, is NOT considered an unstable chronic illness. Participant's or parent's/caregiver's verbal report will suffice as documentation.
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  • Participation in research involving an investigational product (drug/biologic/device) administered within 45 days prior to the first study vaccination.
  • History of a previous laboratory-confirmed diagnosis of SARS-CoV-2 infection or COVID-19.
  • Prior administration of an investigational, authorized, or approved Coronavirus vaccine (ie, against either SARS-CoV, SARS-CoV-2, or MERS CoV) or expected receipt during the period of study follow-up.
  • Previous or current diagnosis of MIS-C.
  • Receipt of medications intended to prevent or treat COVID-19.
  • Received any vaccine within 14 days prior to first study vaccination or planned receipt of any vaccine before Day 49 (ie, 28 days after the second vaccination), except for influenza vaccination, which may be received > 14 days prior to or > 14 days after any study vaccination.
  • Known or suspected congenital or acquired immunodeficiency or autoimmune disease/condition; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy; or long-term systemic corticosteroid therapy (prednisone or equivalent for > 14 continuous days) within 90 days prior to first study vaccination. NOTE: An immunosuppressant dose of glucocorticoid is defined as a systemic dose ≥ 20 mg of prednisone per day or equivalent. The use of topical, inhaled, and nasal glucocorticoids is permitted. Topical tacrolimus and ocular cyclosporin are permitted. Stable autoimmune endocrine disorders (eg, thyroiditis, pancreatitis), including stable diabetes mellitus type 1, or participants with a history of Kawasaki disease are NOT excluded.
  • Received immunoglobulin or blood-derived products within 90 days prior to first study vaccination.
  • Active cancer (malignancy) on chemotherapy within 1 year prior to first study vaccination (with the exception of malignancy cured via excision, at the discretion of the investigator).
  • Any known allergies to products contained in the investigational product.
  • Participants who are breastfeeding a child, pregnant or who plan to become pregnant within 3 months following the last study vaccination.
  • Any other condition that, in the opinion of the investigator, would pose a health risk to the participant if enrolled or could interfere with the evaluation of the trial vaccine or interpretation of study results.
  • Study team member or first-degree relative of any study team member (inclusive of Sponsor, and study site personnel involved in the study).
  • Current participation in any other COVID-19 prevention clinical trial.
  • Participants with a history of myocarditis or pericarditis.

Trial locations and contacts

94 sites in 10 countries.

94 sites in 10 countries

United States47 sites

  • Advanced Research Center

    Anaheim, California, 92805

  • Morehouse School of Medicine

    Atlanta, Georgia, 30310

  • Velocity Clinical Research

    Beachwood, Ohio, 44122

  • Tekton Research Beaumont

    Beaumont, Texas, 77706

  • Coast Clinical Research, LLC

    Bellflower, California, 90706

  • Imagine Research of Palm Beach County

    Boynton Beach, Florida, 33435

  • Palm Harbor Dermatology PA

    Brandon, Florida, 33511

  • Craig A. Spiegel, M.D.

    Bridgeton, Missouri, 63044

  • PanAmerican Clinical Research

    Brownsville, Texas, 78520

  • Tekton Research - Atlanta

    Chamblee, Georgia, 30341

  • WR - ClinSearch, LLC

    Chattanooga, Tennessee, 37421

  • South Texas Clinical Research

    Corpus Christi, Texas, 78404

  • Velocity Clinical Research - Covington, LA

    Covington, Louisiana, 70433

  • Velocity Clinical Research - Covington

    Covington, Louisiana, 70433

  • Dayton Clinical Research

    Dayton, Ohio, 45409

  • Bay Colony Pediatrics

    Dickinson, Texas, 77539

  • Apex Research Group

    Fair Oaks, California, 95628

  • Velocity Clinical Research Grants Pass

    Grants Pass, Oregon, 97527

  • Tribe Clinical Research

    Greenville, South Carolina, 29607

  • Corning Center for Clinical Research

    Horseheads, New York, 14845

  • Trio Clinical Trials

    Houston, Texas, 77008

  • Mercury Clinical Research

    Houston, Texas, 77087

  • Leavitt Clinical Research

    Idaho Falls, Idaho, 83404

  • Westside Center for Clinical Research

    Jacksonville, Florida, 32205

  • Velocity Clinical Research - Lafayette LA

    Lafayette, Louisiana, 70508

  • Alliance for Multispecialty Research

    Layton, Utah, 84041

  • Michael W. Simon, M.D., PSC

    Lexington, Kentucky, 40517

  • Meridian Clinical Research

    Lincoln, Nebraska, 68510

  • Be Well Clinical Studies, LLC

    Lincoln, Nebraska, 68516

  • Preferred Research Partners, Inc.

    Little Rock, Arkansas, 72211

  • Ark Clinical Research

    Long Beach, California, 90815

  • Bluegrass Clinical Research, Inc./All Children Pediatrics

    Louisville, Kentucky, 40243

  • Cordova Research Institute, LLC

    Miami, Florida, 33155

  • Boeson Research

    Missoula, Montana, 59804

  • Clinical Research Associates, Inc.

    Nashville, Tennessee, 37203

  • Orange County Research Institute

    Ontario, California, 91762

  • ARS-Nona Pediatric Center

    Orlando, Florida, 32829

  • Research Your Health

    Plano, Texas, 75093

  • Mercury Clinical Research - Pediatric Center

    Richmond, Texas, 77469

  • Clinical Research Partners, LLC

    Richmond, Virginia, 23226

  • Alliance for Multispecialty Research c/o Wee Care Pediatrics - Roy

    Roy, Utah, 84067

  • Tekton Research

    San Antonio, Texas, 78244

  • California Research Foundation

    San Diego, California, 92123

  • Senders Pediatrics

    South Euclid, Ohio, 44121

  • Lynn Institute of Tulsa

    Tulsa, Oklahoma, 74135

  • Clinical Research of California

    Walnut Creek, California, 94598

  • Velocity Clinical Research - West Jordan

    West Jordan, Utah, 84088

Other trials in United States

South Africa10 sites

  • Tiervlei Trial Centre

    Bellville, Western Cape, 7530

  • REIMED Riger Park

    Boksburg, Gauteng, 1459

  • Setshaba Research Centre

    Ga-Tshwene, Gauteng, 0152

  • Soweto Clinical Trials Centre

    Johannesburg, Gauteng, 1818

  • WiWits RHI - Shandukani Research Centre

    Johannesburg, Gauteng, 2001

  • Wits Vida Nkanyezi Site- Rahima Moosa Mother and Child Hospital

    Johannesburg, Gauteng, 2093

  • Be Part Yoluntu Centre - Paarl

    Paarl, Western Cape, 7655

  • Wits Vida- Chris Hani Baragwanath Hospital

    Soweto, Gauteng, 1862

  • Limpopo Clinical Research Initiative

    Thabazimbi, Limpopo, 0380

  • Stellenbosch University Worcester

    Worcester, Western Cape, 6850

Other trials in South Africa

Mexico8 sites

  • Panamerican Clinical Research, Mexico S.A de C.V.

    Cuernavaca, Morelos, 62290

  • Panamerican Clinical Research S.A de C.V.

    Guadalajara, Jalisco, 44670

  • Centro Multidisciplinario para el Desarrollo Especializado de la Investigacion Clinica en Yucatan S.C.P.

    Mérida, Yucatán, 97130

  • Panamerican Clinical Research Mexico S.A. de C.V. (Queretaro Site)

    Querétaro, 76100

  • Clinical Research Institute S.C.

    Tlalnepantla, 54055

  • Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran

    Tlalpan, Mexico City, 14080

  • Innovacion y Desarrollo en Ciencias de la Salud (IDeCSa)

    Tlalpan, Mexico City, 14090

  • FAICIC S. de R.L. de C.V.

    Veracruz, 91900

Other trials in Mexico

Colombia6 sites

  • Clinica de la costa

    Barranquilla, Atlántico, 80002

  • Centro de Estudios en Infectologia Pediatrica S.A.S.CEIP

    Cali, Valle del Cauca Department, 760042

  • Fundacion Oftalmologica de Santander - FOSCAL

    Floridablanca, Santander Department, 681004

  • Fundacion Centro de Investigacion Clinica - CIC

    Medellín, Antioquia, 50021

  • Centro de Atencion e Investigacion Medica S.A.S-CAIMED

    Puente Aranda, Bogota D.C., 111011

  • Centro de Atencion e Investigacion Medica - CAIMED

    Yopal, Casanare Department, 850007

Other trials in Colombia

Philippines6 sites

  • Medical Mission Group Hospital-Lucban and Southern Luzon State University

    Lucena City, Quezon, 4328

  • Manila Doctors Hospital

    Manila, National Capital Region, 1000

  • University of the Philippines - Philippine General Hospital

    Manila, National Capital Region, 1000

  • National Children's Hospital

    Quezon City, National Capital Region, 1102

  • FEU-NRMF

    Quezon City, National Capital Region, 1118

  • University of the Philippines Manila - National Institutes of Health (NIH) - Institute of

    San Juan City, Batangas, 4226

Other trials in Philippines

Dominican Republic5 sites

  • PROBEBE en Hospital Universitario Maternidad Nuestra Senora de la Altagracia

    Santo Domingo, Nacional, 10205

  • Instituto Dermatologico y Cirugia de Piel Dr. Huberto Bogaert Diaz IDCP

    Santo Domingo, Nacional, 10306

  • MEDYVAC INTERNACIONAL SRL en Clinica Cruz Jiminian

    Santo Domingo, Nacional, 10601

  • Registrum Group (Hospital Regional Marcelino Velez)

    Santo Domingo, Nacional, 11005

  • Registrum Group (Hospital Materno Infantil San Lorenzo de Los Mina)

    Santo Domingo, Nacional, 11901

Other trials in Dominican Republic

Spain4 sites

  • Hospital Universitario Severo Ochoa

    Leganés, Madrid, 28911

  • Hospital Universitario 12 de Octubre

    Madrid, 28041

  • Complejo Hospitalario Universitario de Santiago

    Santiago de Compostela, A Coruña, 15706

  • Hospital Universitario de Torrejon

    Torrejón de Ardoz, Madrid, 28850

Other trials in Spain

Guatemala3 sites

  • Centro de Investigaciones Pediátricas (CIP)

    Guatemala City, 01001

  • SMI (Servicios Medicos Integrales)

    Guatemala City, 01007

  • CECLISA

    Guatemala City, 01009

Other trials in Guatemala

Honduras3 sites

  • DEMEDICA

    San Pedro Sula, Cortés Department, 21104

  • Inverime S.A.

    Tegucigalpa, Francisco Morazán Department, 11101

  • Investigacion Sin Limites

    Tegucigalpa, Francisco Morazán Department, 11101

Other trials in Honduras

United Kingdom2 sites

  • Lakeside Healthcare Research

    Corby, Northamptonshire, NN17 2UR

  • St Georges Hospital

    London, SW17 0QT

Other trials in United Kingdom

About this study

Official title: A Phase 2/3 Age De-escalating Study to Evaluate the Safety and Immunogenicity of a SARS-CoV-2 Recombinant Spike Protein Vaccine (SARS-CoV-2 rS) With Matrix-M™ Adjuvant in Children 6 Months to < 12 Years of Age

This is a Phase 2/3 randomized, observer-blinded, placebo-controlled, age de-escalation trial to evaluate the safety and immunogenicity of 2 primary doses of SARS-CoV-2 rS with Matrix-M™ adjuvant (NVX-CoV2373) given 21 days apart and NVX CoV2373 or a variant-based vaccine given as a booster dose or at crossover in pediatric participants (3 age cohorts; 6 to < 12 years, 2 to < 6 years, and 6 to < 24 months of age). Each age cohort will be conducted in 2 parts starting with the oldest age cohort (6 to < 12 years of age).

Read the detailed description

This is a Phase 2/3 randomized, observer-blinded, placebo-controlled, age de-escalation trial to evaluate the safety and immunogenicity of 2 primary doses of SARS-CoV-2 rS with Matrix-M™ adjuvant (NVX-CoV2373) given 21 days apart and NVX CoV2373 or a variant-based vaccine given as a booster dose or at crossover in pediatric participants (3 age cohorts; 6 to < 12 years, 2 to < 6 years, and 6 to < 24 months of age).

Each age cohort will be conducted in 2 parts starting with the oldest age cohort (6 to < 12 years of age).

Part 1 will enroll approximately 120 healthy or medically stable sentinel participants per age cohort (10% of the intended enrollment population per age cohort, for a total of 360 sentinel participants overall) who will be randomized in a 1:1 ratio to receive 2 doses of NVX-CoV2373 or placebo with doses given 21 days apart.

Part 2 will enroll a larger number of healthy or medically stable participants (N= approximately 1,080 per age cohort), for a total of approximately 3,240 pediatric participants enrolled in Part 2, and a total of approximately 3,600 participants enrolled in the entire trial). Initial randomization in Part 2 will be in a 2:1 ratio, and the safety and effectiveness of 2 doses of NVX-CoV2373 given 21 days apart will be assessed.

Conditions
COVID-19
Being tested
SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period), Placebo
Medical subject headings
COVID-19

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period)Biological

    Also called NVX-CoV2373

    Alternating intramuscular (deltoid) injections of SARS-CoV-2 rS co-formulated with Matrix-M1 adjuvant (0.5 mL) (or fractional dose if necessary) on Days 0 and 21 in the Initial Vaccination Period.

  • PlaceboOther

    Also called Sodium chloride 0.9% (BP, sterile)

    Alternating intramuscular (deltoid) injections of placebo (0.5 mL) on Days 0 and 21 in the Initial Vaccination Period or on Days 201 or Day 229 in the Booster Vaccination Period

Study groups in NCT05468736
Study groupRoleWhat they receive
Cohort-1(6 to < 12 y)-Part-1(Active Vaccine)ExperimentalNVX-CoV2373 (SARS-CoV-2 rS: 5 µg + Matrix-M adjuvant: 50 µg in 0.5 mL)
Receives: Biological: SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period)
Cohort-1(6 to < 12 y)-Part-1(Placebo)Placebo comparatorPlacebo (normal saline)
Receives: Other: Placebo
Cohort-1(6 to < 12 y)-Part-2(Active Vaccine)ExperimentalNVX-CoV2373 (SARS-CoV-2 rS: 5 µg + Matrix-M adjuvant: 50 µg in 0.5 mL)
Receives: Biological: SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period)
Cohort-1(6 to < 12 y)-Part-2(Placebo)Placebo comparatorPlacebo (normal saline)
Receives: Other: Placebo
Cohort-2(2 to < 6 y)-Part-1(Active Vaccine)ExperimentalNVX-CoV2373 (SARS-CoV-2 rS: 5 µg + Matrix-M adjuvant: 50 µg in 0.5 mL)
Receives: Biological: SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period)
Cohort-2(2 to < 6 y)-Part-1(Placebo)Placebo comparatorPlacebo (normal saline)
Receives: Other: Placebo
Cohort-2(2 to < 6 y)-Part-2(Active Vaccine)ExperimentalNVX-CoV2373 (SARS-CoV-2 rS: 5 µg + Matrix-M adjuvant: 50 µg in 0.5 mL)
Receives: Biological: SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period)
Cohort-2(2 to < 6 y)-Part-2(Placebo)Placebo comparatorPlacebo (normal saline)
Receives: Other: Placebo
Cohort-3(6 to < 24 m)-Part-1(Active Vaccine)ExperimentalNVX-CoV2373 (SARS-CoV-2 rS: 5 µg + Matrix-M adjuvant: 50 µg in 0.5 mL)
Receives: Biological: SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period)
Cohort-3(6 to < 24 m)-Part-1(Placebo)Placebo comparatorPlacebo (normal saline)
Receives: Other: Placebo
Cohort-3(6 to < 24 m)-Part-2ExperimentalNVX-CoV2373 (SARS-CoV-2 rS: 5 µg + Matrix-M adjuvant: 50 µg in 0.5 mL)
Receives: Biological: SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period)
Cohort-3(6 to < 24 m)-Part-2(Placebo)Placebo comparatorPlacebo (normal saline)
Receives: Other: Placebo

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Reactogenicity Incidence and Severity

    Reactogenicity incidence, duration, and severity (mild, moderate, severe, or potentially life-threatening) recorded by parent(s)/caregiver(s) on an electronic patient-reported outcome diary application (eDiary) on days of vaccination and subsequent 6 days (total 7 days after each vaccine injection).

    Measured: Day 0 to Day 7

  2. Incidence and Severity of Medically Attended Adverse Events (MAAEs)

    Incidence and severity of MAAEs through 28 days after second injection of each set of vaccinations (initial and crossover), and after a booster dose.

    Measured: Day 0 to Day 28

  3. Incidence and Severity of Unsolicited Adverse Events (AEs)

    Incidence and severity of unsolicited AEs through 28 days after second injection of each set of vaccinations (initial and crossover), and after a booster dose.

    Measured: Day 0 to Day 28

  4. Incidence and Severity of MAAEs Attributed to Study Vaccine

    Incidence and severity of MAAEs attributed to study vaccine after initial vaccination at Day 0 through Month 24 or the EoS.

    Measured: Day 0 to Day 730

  5. Incidence and Severity of Serious Adverse Events (SAEs)

    Incidence and severity of SAEs after initial vaccination at Day 0 through Month 24 or the EoS.

    Measured: Day 0 to Day 730

  6. Incidence and Severity of Adverse Events of Special Interest (AESIs)

    Incidence and severity of AESIs (including multisystem inflammatory syndrome in children [MIS-C], and myocarditis and/or pericarditis) after initial vaccination at Day 0 through Month 24 or the EoS.

    Measured: Day 0 to Day 730

  7. Death due to any cause

    Death due to any cause occurring from Day 0 to EoS.

    Measured: Day 0 to Day 730

Secondary outcomes (21)

  1. Participants with PCR positive mild, moderate or severe COVID-19 after the primary series of 2 doses

    Incidence rate of participants with first episode of PCR-positive mild, moderate, or severe COVID-19 overall and per age cohort, with or without positive anti-NP serology at baseline after the primary series of 2 doses.

    Measured: Day 0 to Day 730

  2. Participants with PCR positive moderate or severe COVID-19 after the primary series of 2 doses

    Incidence rate of participants with first episode of PCR-positive moderate or severe COVID-19 overall and per age cohort, with or without positive anti-NP serology at baseline, and by risk factors to develop severe COVID-19 after the primary series of 2 doses.

    Measured: Day 0 to Day 730

  3. Participants with diagnostic test - positive asymptomatic, mild, moderate or severe COVID-19 after the primary series of 2 doses

    Incidence rate of participants with first episode of diagnostic test-positive asymptomatic, mild, moderate, or severe COVID-19 (regardless of confirmatory test used, ie, PCR or rapid antigen test, and of testing location, ie, central or externally tested) overall and per age cohort, with or without positive anti-NP serology at baseline after the primary series of 2 doses.

    Measured: Day 0 to Day 730

  4. Participants with diagnostic test - positive moderate or severe COVID-19 after the primary series of 2 doses

    Incidence rate of participants with first episode of diagnostic test-positive moderate or severe COVID-19 (regardless of confirmatory test used, ie, PCR or rapid antigen test, and of testing location, ie, central or externally tested) overall and per age cohort, with or without positive anti NP serology at baseline, and by risk factors to develop severe COVID-19 after the primary series of 2 doses.

    Measured: Day 0 to Day 730

  5. Participants with PCR positive mild, moderate or severe COVID-19 after the booster dose

    Incidence rate of participants with first episode of PCR-positive mild, moderate, or severe COVID-19 overall and per age cohort, with or without positive anti-NP serology at baseline after the booster dose.

    Measured: Day 0 to Day 730

  6. Participants with PCR positive moderate or severe COVID-19 after the booster dose

    Incidence rate of participants with first episode of PCR-positive moderate or severe COVID-19 overall and per age cohort, with or without positive anti-NP serology at baseline, and by risk factors to develop severe COVID-19 after the booster dose.

    Measured: Day 0 to Day 730

  7. Participants with diagnostic test - positive asymptomatic, mild, moderate or severe COVID-19 after the booster dose

    Incidence rate of participants with first episode of diagnostic test-positive asymptomatic, mild, moderate, or severe COVID-19 (regardless of confirmatory test used, ie, PCR or rapid antigen test, and of testing location, ie, central or externally tested) overall and per age cohort, with or without positive anti-NP serology at baseline after the booster dose.

    Measured: Day 0 to Day 730

  8. Participants with diagnostic test moderate or severe COVID-19 after the booster dose

    Incidence rate of participants with first episode of diagnostic test-positive moderate or severe COVID-19 (regardless of confirmatory test used, ie, PCR or rapid antigen test, and of testing location, ie, central or externally tested) overall and per age cohort, with or without positive anti-NP serology at baseline after the booster dose, and by risk factors to develop severe COVID-19.

    Measured: Day 0 to Day 730

  9. Antibodies to SARS-CoV-2 Nucleoprotein (NP) at Specified Time Points

    Antibodies to SARS-CoV-2 NP, regardless of whether the infection was symptomatic. Antibodies to SARS-CoV-2 NP at Days 0 and 35, at Crossover Visit 1, at Booster vaccination visit, and at Months 12 and 24 will be used to determine natural infection and to determine the incidence of asymptomatic infection acquired during study follow-up.

    Measured: Day 0 to Day 730

  10. Neutralizing antibody response, post-booster, by age cohort,seronegative to anti-SARS-CoV-2 NP antibodies at baseline and pre-booster

    Neutralizing antibody response at 28 days post booster for pediatric participants in the Immunogenicity Population overall and by age cohort, seronegative to anti-SARS-CoV-2 NP antibodies at baseline and pre-booster, compared with that observed at 28 days post-booster vaccination in young adult participants 18 to < 26 years of age.

    Measured: Day 0 to Day 28

  11. Neutralizing antibody response, by age cohort, regardless of serostatus at baseline and pre-booster

    Neutralizing antibody response at 28 days post-booster for pediatric participants in the Immunogenicity Population overall and by age cohort, regardless of serostatus at baseline and pre-booster, compared with that observed in pediatric participants at baseline (Day 0).

    Measured: Day 0 to Day 28

  12. Serum IgG levels to SARS-CoV-2 S protein, post-booster, by age cohort, regardless of serostatus at baseline and pre-booster vaccination

    Serum IgG levels to SARS-CoV-2 S protein at 28 days post-booster vaccination for pediatric participants in the Immunogenicity Population overall and by age cohort, regardless of serostatus at baseline and pre-booster vaccination, compared with that observed at 28 days post-booster vaccination in young adult participants 18 to < 26 years of age.

    Measured: Day 0 to Day 28

  13. Serum IgG levels to SARS-CoV-2 S protein, post booster, by age cohort, regardless of serostatus at baseline and pre-booster

    Serum IgG levels to SARS-CoV-2 S protein at 28 days post-booster for pediatric participants in the Immunogenicity Population overall and by age cohort, regardless of serostatus at baseline and pre-booster, compared with that observed in pediatric participants at baseline (Day 0).

    Measured: Day 0 to Day 28

  14. Serum IgG levels to SARS-CoV-2 S protein , post booster, by age cohort, regardless of serostatus at baseline and pre-booster

    Serum IgG levels to SARS-CoV-2 S protein at 28 days post-booster for pediatric participants in the Immunogenicity Population overall and by age cohort, regardless of serostatus at baseline and pre-booster, compared with that observed in pediatric participants at Day 35,

    Measured: Day 0 to Day 35

  15. Neutralizing antibody response for pediatric participants and adult participants expressed as Geometric Mean Titers (GMT)

    Neutralizing antibody response for pediatric participants compared with adult participants 18 to < 26 years of age from the Adult Main Study at Day 35

    Measured: Day 35

  16. Neutralizing antibody response for pediatric participants and adult participants expressed as Sero response (SRR)

    Neutralizing antibody response for pediatric participants compared with adult participants 18 to < 26 years of age from the Adult Main Study at Day 35

    Measured: Day 35

  17. Serum IgG levels to SARS-CoV-2 S protein after second injection of the initial vaccination series

    Serum IgG levels to SARS-CoV-2 S protein 14 days after second injection of the initial vaccination series (Day 35) in pediatric participants in the Immunogenicity Population by age cohort and subsets with and without anti-NP antibodies at baseline.

    Measured: Day 35

  18. Treatment and severity of COVID 19 after a PCR-confirmed case

    Description of course, treatment and severity of COVID 19 reported after a PCR-confirmed case via the Case Form.

    Measured: Day 0 to Day 730

  19. Antibodies to SARS-CoV-2 NP, regardless of whether the infection was symptomatic.

    Antibodies to SARS-CoV-2 NP, regardless of whether the infection was symptomatic. Antibodies to SARS-CoV-2 NP at Days 0 and 35, at Crossover Visit 1, at Booster vaccination visit, and at Months 12 and 24 will be used to determine natural infection and to determine the incidence of asymptomatic infection acquired during study follow-up.

    Measured: Day 0 to Day 730

  20. Serum IgG levels to SARS-CoV-2 S protein expressed as GMT

    Serum IgG levels to SARS-CoV-2 S protein at Months 6 (pre- booster), 7/8 (1-month post-booster), 12, and 24 post-vaccination with NVXCoV2373.

    Measured: Day 180 to Day 730

  21. MN titers to SARS-CoV-2 S protein expressed as GMT

    MN titers at Months 6 (pre- booster), 7/8 (1-month post-booster), 12, and 24 post-vaccination with NVXCoV2373.

    Measured: Day 180 to Day 730

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted21 Jul 2022
  2. Study start22 Jul 2022
  3. Primary completion16 Jan 2024
  4. Study completion25 Oct 2025

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 2/3
Primary purpose
Prevention
Allocation
Randomised
Intervention model
Crossover
Masking
Triple blind
Who is masked
Participant, Care provider, Investigator
Enrolment
3,600 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05468736
Sponsor's protocol ID
2019nCoV-503
Acronym
COVID-19
Status last verified
May 2026
First submitted
18 Jul 2022
Last updated
22 May 2026
Results posted
No
Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No

Questions about this trial

What is this clinical trial studying?

A Phase 2/3 study testing SARS-CoV-2 rS/Matrix-M1 Adjuvant (Initial Vaccination Period) in people with COVID-19, run by Novavax at 94 sites in 10 countries.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 6 inclusion and 21 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 22 May 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 94 sites in United States, South Africa, Mexico, Colombia, Philippines and 5 more countries. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this combined phase mean?

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Reactogenicity Incidence and Severity (time frame: Day 0 to Day 7). The study lists 7 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05468736.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 May 2026.

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