A Phase 3 interventional study of IIV-HD (standalone) and NVXC19 (EU licensed, standalone) in Immunization, Healthy Volunteers and COVID-19 Immunization, sponsored by Sanofi. Not yet recruiting. Open to participants aged 60 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-22.
Sponsored by Sanofi · Phase 3, Interventional, and Prevention
The purpose of this study is to assess the safety and immunogenicity of IIV-HD + NVXC19 vaccine compared to seasonal influenza vaccine (IIV-HD) and COVID-19 vaccine, adjuvanted (NVXC19) coadministered in adult participants 60 years of age and older. Placebo will be coadministered in the IIV-HD + NVXC19 study group to control for the number of injections and to maintain observer-blinding. Thus, each participant will receive 2 injections at enrollment, one in each deltoid muscle.Study details include:• The study duration will be approximately 12 months per participant• Study intervention will be administered via a single IM injection into the right and left deltoid muscles on day (D)01
2,264 studies on the registry are indexed under Influenza, Human; 173 are open to participants now.
This study's planned enrollment of 6,000 is above the median of 240 across 1,894 interventional studies indexed under Influenza, Human.
Browse Influenza, Human studies →Sanofi is the lead sponsor of 1,547 studies on the registry; 88 are open to participants now.
Of its 204 completed or terminated interventional studies of FDA-regulated products, 122 (60%) have results posted.
Counted across the registry records on this site, refreshed daily.
Inclusion Criteria: Inclusion criteria to be checked at Screening Visit:
Inclusion criteria to be checked at Visit 1 (D01)
The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.
IIV-HD and NVXC19 co-administered in opposite deltoid muscles
Drug: IIV-HD (standalone) · Drug: NVXC19 (EU licensed, standalone)
IIV-HD + NVXC19 and Placebo co-administered in opposite deltoid muscles
Drug: IIV-HD + NVXC19 combination · Drug: Placebo, normal saline
Pharmaceutical form: Suspension Route of administration: Intramuscular injection
Pharmaceutical form: Dispersion Route of administration: Intramuscular injection
Pharmaceutical form: Suspension Route of administration: Intramuscular injection
Pharmaceutical form: Solution Route of administration: Intramuscular injection
Antibody titers against for each of the 3 influenza vaccine strains(in a subset of participants)
Geometric mean (GMT) of antibody titers measured by hemagglutination inhibition (HAI)
Time frame: At Day 28 after vaccination
Antibody titers against SARS-CoV-2 specific variant(in a subset of participants)
Geometric mean (GMT) of antibody titers measured by pseudovirus neutralization test (PNT)
Time frame: At Day 28 after vaccination
Presence of solicited injection site reactions for 8 days, including the day of vaccination (Main subset of participants)
Number of participants with solicited injection site reactions pre-listed in the participant diary and case report form (CRF)
Time frame: Up to 8 each days after vaccination
Presence of solicited systemic reactions for 8 days, including the day of vaccination (Main subset of participants)
Number of participants with solicited systemic reactions pre-listed in the participant diary and case report form (CRF)
Time frame: Up to 8 each days after vaccination
Presence of immediate adverse events after vaccination
Number of participants with immediate adverse events (AEs). Immediate adverse events are any unsolicited systemic adverse events within 30 minutes after vaccination
Time frame: Within the 30 minutes after vaccination
Presence of unsolicited adverse events
Number of participants with unsolicited adverse events (AEs) for 28 days, including the day of vaccination
Time frame: Up to 28 days after vaccination
Presence of all medically attended adverse events
Number of participants with medical attended adverse events (MAAEs) for 180 days, including the day of vaccination
Time frame: Up to 180 days after vaccination
Presence of related medically attended adverse events linked to predefined potential immune-mediated diseases
Number of participants with medical attended adverse events (MAAEs) linked to predefined potential immune-mediated diseases (PIMDs) following the study vaccination
Time frame: From Day 181 through 12 months following study vaccination
Presence of all adverse events of special interest
Number of participants with adverse events of special interest (AESIs) for 180 days, including the day of vaccination
Time frame: Up to 180 days after vaccination
Presence of all serious adverse events
Number of participants with serious adverse events (SAEs) for 180 days, including the day of vaccination
Time frame: Up to 180 days after vaccination
Presence of related serious adverse events
Number of participants with serious adverse events (SAEs) from D181 through 12 months following the last study vaccination
Time frame: From Day 181 through 12 months following study vaccination
Presence of related adverse events of special interest
Number of participants with adverse events of special interest (AESIs) from D181 through 12 months following the last study vaccination
Time frame: From Day 181 through 12 months following study vaccination
Presence of related medical attended adverse events linked to predefined potential immune-mediated diseases that meet the criteria for serious adverse events
Number of patients with medical attended adverse events (MAAES) linked to predefined potential immune-mediated diseases (PIMDs) meets criteria for serious adverse events (SAEs) from D181 through 12 months following the last study vaccination
Time frame: From Day 181 through 12 months following study vaccination
Presence of adverse events leading to study discontinuation throughout the study
Number of participants with adverse events lead to study discontinuation
Time frame: From Day 01 through 12 months
Influenza seroconversion status after vaccination for each of the 3 influenza vaccine strains
Percentage of participants Seroconversion is defined by: pre-injection antibody titer \< 10 \[1/dil\] at D01 and post-injection antibody titer ≥ 40 \[1/dil\] at D29, or pre-injection antibody titer ≥ 10 \[1/dil\] at D01 and a ≥ 4-fold increase in titer at D29
Time frame: At Day 29
SARS-CoV-2 seroresponse status after vaccination
Percentage of participantsSeroresponse to SARS-CoV-2 is defined by: pre-injection antibody titer \< LLOQ \[1/dil\] and post-injection antibody titer ≥ 4\*LLOQ \[1/dil\] at D29, or pre-injection antibody titer ≥ LLOQ \[1/dil\] at D01 and a ≥ 4-fold increase in titer \[1/dil\] at D29
Time frame: At Day 29
Neutralizing antibody titers measured by neutralization test (NT) against each of the 3 influenza vaccine strains before and after vaccination (in a subset of participants)
Neutralizing antibody titers \[1/dil\]
Time frame: At Day 01 and Day 29
Individual neutralizing antibody titer ratio measured by neutralization test NT against each of the 3 influenza vaccine strains after vaccination (in a subset of participants)
Individual neutralizing titers ratio Day 29/Day 01
Time frame: At Day 01 and Day 29
Neutralizing antibody titer against each of the 3 influenza vaccine strains after vaccination(in a subset of participants)
Percentage of participants with neutralization test (NT) titer ≥ 10 (1/dil)
Time frame: At Day 29
Neutralizing antibody titer against each of the 3 influenza vaccine strains after vaccination (in a subset of participants)
Percentage of participants with neutralization test (NT) titer ≥ 20 (1/dil)
Time frame: At Day 29
Neutralizing antibody titer against each of the 3 influenza vaccine strains after vaccination (in a subset of participants)
Percentage of participants with neutralization test (NT) titer ≥ 40 (1/dil)
Time frame: At Day 29
Neutralizing antibody titer against each of the 3 influenza vaccine strains after vaccination (in a subset of participants)
Percentage of participants with neutralization test (NT) titer ≥ 80 (1/dil)
Time frame: At Day 29
Fold increase in neutralization test antibody titer against each of the 3 influenza vaccine strains after vaccination (in a subset of participants)
Percentage of participants fold increase is defined in neutralization test (NT) antibody titer \[post/pre\] ≥ 2-fold rise from Day 01 to Day 29
Time frame: At Day 29
Fold increase in neutralization test antibody titer against each of the 3 influenza vaccine strains after vaccination (in a subset of participants)
Percentage of participants fold increase is defined in neutralization test (NT) antibody titer \[post/pre\] ≥ 4-fold rise from Day 01 to Day 29
Time frame: At Day 29
No study locations are listed for this record.
Plan to share: Yes — Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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