Combination Vaccine for COVID-19 and Flu

Not currently recruiting at 11 trial locations

Overseen By Trial Transparency email recommended (Toll free for US & Canada)

Age: 18+

Sex: Any

Trial Phase: Phase 1 & 2

Sponsor: Sanofi

Must not be taking: Immunosuppressants, Anticoagulants

Disqualifiers: Immunodeficiency, Bleeding disorder, Stroke, others

Stay on Your Current Meds You can continue your current medications while participating

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 2 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 2

Duration: 1 day

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to test the safety and immune response of a new combination vaccine for flu and COVID-19. Participants will receive either different versions of the new vaccine or existing vaccines to determine which works best. The trial involves two injections given at the start. Individuals who have completed their COVID-19 vaccinations and booster, and can receive shots in both arms, might be suitable candidates.

As a Phase 1 trial, the research focuses on understanding how the treatment works in people, offering participants the opportunity to be among the first to receive this new combination vaccine.

Do I need to stop my current medications to join the trial?

The trial information does not specify if you need to stop taking your current medications. However, if you are on immunosuppressive therapy or long-term systemic corticosteroids, you may not be eligible to participate.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research shows that the combination vaccine, which includes a high-dose flu shot and a COVID-19 shot, is generally well-tolerated. Studies have found that vaccines like this can create a strong immune response, especially in older adults. Common reactions include soreness at the injection site, while serious side effects have not been widely reported.

Previous studies on similar vaccines show they can cause mild reactions, such as tiredness or headache, but these usually resolve on their own. The flu shot part of this combination has been used safely for many years. The COVID-19 shot part uses technology found in other approved vaccines, which helps ensure its safety.

This trial is in its early stages, so researchers are still collecting data on safety and effectiveness. However, the decision to proceed with testing suggests confidence in the treatment's safety so far. Participants should consult their doctor about any personal health concerns before joining a trial. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about the combination vaccine for COVID-19 and flu because it aims to protect against both viruses in a single shot. Unlike current options where separate vaccines are required for COVID-19 and the flu, this combo uses IIV-HD (a high-dose influenza vaccine) with rC19 (a recombinant COVID-19 vaccine) to streamline immunization. This approach could simplify vaccination schedules and improve compliance, especially important during peak flu season when COVID-19 is also a concern. Additionally, by targeting both conditions simultaneously, it may enhance overall public health outcomes by reducing the burden of these respiratory illnesses.

What evidence suggests that this trial's treatments could be effective for COVID-19 and flu?

Research has shown that the combined vaccine IIV-HD + rC19, currently under trial, appears promising for protecting against both COVID-19 and the flu. Studies have found that this dual vaccine generates a stronger immune response against both viruses compared to separate vaccines. For older adults, it produces a better immune response than the regular flu shot. Additionally, previous tests have shown the vaccine to be well-tolerated and effective in triggering an immune response. This suggests it could be more effective in preventing both COVID-19 and the flu. Participants in this trial will receive different doses and combinations of IIV-HD + rC19 to further evaluate its effectiveness and safety. ^{1 3 6 7 8}

Are You a Good Fit for This Trial?

Adults aged 50 and older who have completed their primary COVID-19 vaccination series plus a booster can join this trial. They must be healthy or have stable pre-existing conditions, able to get shots in both arms, attend all visits, and follow study procedures. Women must not be able to bear children or agree to use contraception.

Inclusion Criteria

I can attend all required visits and follow the study rules.

My eligibility for the trial will be confirmed at my screening visit.

I have signed the consent form for the trial.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive two intramuscular injections, one in each deltoid muscle, on Day 01

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and immunogenicity, with follow-up calls and visits at D09, D30, D182, and D366

12 months

1 visit (in-person), 3 visits (telephone calls)

What Are the Treatments Tested in This Trial?

Interventions

• IIV-HD + rC19

Trial Overview The trial is testing the safety and immune response of a high-dose flu shot combined with different levels of a new COVID-19 vaccine compared to each vaccine alone or with placebo. Participants will receive two injections at the start and will be monitored for about one year.

How Is the Trial Designed?

Group I: Group 7: IIV-HD + rC19 (dose 4) (in right or left deltoid) and placebo (in opposite deltoid) Experimental Treatment 2 Interventions

two IM injections on D01

Group II: Group 6: IIV-HD + rC19 (dose 3) (in right or left deltoid) and placebo (in opposite deltoid) Experimental Treatment 2 Interventions

two IM injections on D01

Group III: Group 5: IIV-HD + rC19 (dose 2) (in right or left deltoid) and placebo (in opposite deltoid) Experimental Treatment 2 Interventions

two IM injections on D01

Group IV: Group 4: IIV-HD + rC19 (dose 1) (in right or left deltoid) and placebo (in opposite deltoid) Experimental Treatment 2 Interventions

two IM injections on D01

Group V: Group 3: IIV-HD (in right or left deltoid) and rC19 (dose1) (in opposite deltoid) Experimental Treatment 2 Interventions

two IM injections on D01

Group VI: Group 2: rC19 (dose 1) (in right or left deltoid) and placebo (in opposite deltoid) Experimental Treatment 2 Interventions

two IM injections on D01

Group VII: Group 1: IIV-HD (in right or left deltoid) and placebo (in opposite deltoid) Experimental Treatment 2 Interventions

two IM injections on D01

IIV-HD + rC19 is already approved in United States, European Union for the following indications:

Approved in United States as Spikevax for:

• Active immunization to prevent coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in individuals 12 years of age and older.

Approved in European Union as Spikevax for:

• Active immunization to prevent coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in individuals 12 years of age and older.

Who Is Running the Clinical Trial?

Sanofi

Lead Sponsor

Trials

2,246

Recruited

4,085,000+

Paul Hudson

Sanofi

Chief Executive Officer since 2019

Degree in Economics from Manchester Metropolitan University

Christopher Corsico

Sanofi

Chief Medical Officer

MD from Cornell University, MPH in Chronic Disease Epidemiology from Yale University

Published Research Related to This Trial

The Abdala vaccine, a novel SARS-CoV-2 receptor-binding domain vaccine, was found to be safe and well tolerated in a phase 1-2 trial with 792 participants, showing minimal adverse reactions mostly limited to mild injection site discomfort.

The vaccine induced strong immune responses, with seroconversion rates of 95.2% in the 50 µg group and 81% in the 25 µg group after the short immunization schedule, significantly outperforming the placebo group, which had a 0% seroconversion rate.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety, tolerability, and immunogenicity of a SARS-CoV-2 recombinant spike RBD protein vaccine: A randomised, double-blind, placebo-controlled, phase 1-2 clinical trial (ABDALA Study). Hernández-Bernal, F., Ricardo-Cobas, MC., Martín-Bauta, Y., et al.[2022]

The heterologous COVID-19 vaccine using rAd26 and rAd5 vectors was found to be safe and well tolerated among 76 healthy adult participants, with mild adverse events like injection site pain and headache being the most common, and no serious adverse events reported.

Both frozen and lyophilised formulations of the vaccine induced strong immune responses, with 100% of participants producing antibodies against SARS-CoV-2 and significant T-cell responses detected, indicating promising immunogenicity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety and immunogenicity of an rAd26 and rAd5 vector-based heterologous prime-boost COVID-19 vaccine in two formulations: two open, non-randomised phase 1/2 studies from Russia. Logunov, DY., Dolzhikova, IV., Zubkova, OV., et al.[2022]

A study involving 451 adults showed that inhaled adenovirus-vectored COVID-19 vaccines, including a bivalent and a variant-specific option, were safe and well tolerated, with mostly mild to moderate side effects and no serious adverse events reported.

The bivalent vaccine induced a significantly higher level of neutralizing antibodies against the Omicron variant compared to the standard vaccine, suggesting it may provide enhanced protection against SARS-CoV-2 variants.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety and immunogenicity of heterologous boosting with orally administered aerosolized bivalent adenovirus type-5 vectored COVID-19 vaccine and B.1.1.529 variant adenovirus type-5 vectored COVID-19 vaccine in adults 18 years and older: a randomized, double blinded, parallel controlled trial. Xu, JW., Wang, BS., Gao, P., et al.[2023]

The ARCoV mRNA vaccine was found to be safe and well-tolerated across all five tested doses, with no serious adverse events reported within 56 days after vaccination, although mild to moderate reactions like fever were common, especially at higher doses.

The vaccine induced strong immune responses, with significant increases in neutralizing antibodies and T-cell responses observed after the second dose, particularly at the 15 μg dose, which produced antibody levels about twice as high as those found in recovered COVID-19 patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety and immunogenicity of the SARS-CoV-2 ARCoV mRNA vaccine in Chinese adults: a randomised, double-blind, placebo-controlled, phase 1 trial. Chen, GL., Li, XF., Dai, XH., et al.[2023]

The ΔNA(RBD)-Flu vaccine, which uses an influenza virus modified to include the SARS-CoV-2 Spike receptor binding domain, successfully generates strong neutralizing antibody responses in mice, comparable to those seen in humans after natural infection.

This vaccine candidate is safe, as it does not cause disease in mice, and could potentially be produced at scale using existing influenza vaccine production methods.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Attenuated influenza virions expressing the SARS-CoV-2 receptor-binding domain induce neutralizing antibodies in mice. Loes, AN., Gentles, LE., Greaney, AJ., et al.[2023]

The PHH-1V recombinant protein vaccine, targeting SARS-CoV-2 variants B.1.351 and B.1.1.7, showed 100% efficacy in preventing mortality in infected mice and effectively reduced infections from the Beta, Delta, and Omicron variants.

Immunization with PHH-1V induced strong T cell responses and neutralizing antibodies, demonstrating a good safety profile and the potential for this vaccine strategy to combat evolving SARS-CoV-2 variants.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Preclinical evaluation of a COVID-19 vaccine candidate based on a recombinant RBD fusion heterodimer of SARS-CoV-2. Barreiro, A., Prenafeta, A., Bech-Sabat, G., et al.[2023]

The novel vaccine CoroVaxG.3, based on a chimeric human adenovirus vector, demonstrated significantly enhanced Spike protein expression and induced strong humoral and T-cell immunity after a single dose, lasting at least 5 months.

Sera from vaccinated mice showed the ability to neutralize various SARS-CoV-2 variants, including the Delta variant, indicating its potential effectiveness against emerging strains and making it a promising candidate for clinical trials.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A Single Dose of a Hybrid hAdV5-Based Anti-COVID-19 Vaccine Induces a Long-Lasting Immune Response and Broad Coverage against VOC. López, MV., Vinzón, SE., Cafferata, EGA., et al.[2022]

In a study of 160 healthcare workers, the NVX-CoV2373 vaccine as a second booster resulted in significantly lower antibody responses against SARS-CoV-2 variants compared to mRNA vaccines.

Participants receiving NVX-CoV2373 experienced a higher rate of new SARS-CoV-2 infections but reported fewer adverse events, suggesting a trade-off between safety and immunogenicity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Immunogenicity and safety of heterologous booster with protein-based COVID-19 vaccine (NVX-CoV2373) in healthy adults: A comparative analysis with mRNA vaccines. Sheng, WH., Lin, PH., Cheng, YC., et al.[2023]

The Covax-19 vaccine, designed using the SARS-CoV-2 spike protein, demonstrated strong immunogenicity in mice and ferrets, inducing high levels of neutralizing antibodies and T-cell responses against both the original virus and the B.1.1.7 variant.

Ferrets immunized with Covax-19 showed complete protection from SARS-CoV-2 after intranasal challenge, with no detectable virus in their lungs, indicating potential for both individual protection and reduced virus transmission.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Immunisation of ferrets and mice with recombinant SARS-CoV-2 spike protein formulated with Advax-SM adjuvant protects against COVID-19 infection. Li, L., Honda-Okubo, Y., Huang, Y., et al.[2022]

The V-01 COVID-19 vaccine demonstrated a promising safety profile in a Phase I clinical trial with 25% of participants experiencing mild vaccine-related adverse events, but no severe reactions were reported.

The vaccine effectively induced strong immune responses, with high levels of neutralizing antibodies observed, particularly in the low dose (10 μg) subgroup and among elderly participants, suggesting it could be suitable for all age groups.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety and immunogenicity of a recombinant interferon-armed RBD dimer vaccine (V-01) for COVID-19 in healthy adults: a randomized, double-blind, placebo-controlled, Phase I trial. Zhang, J., Hu, Z., He, J., et al.[2021]

Most adverse events reported from COVID-19 vaccines were mild or moderate, indicating a generally favorable safety profile during clinical trials.

However, some viral vector-based vaccines were associated with thrombotic events, highlighting the need for ongoing studies and post-marketing surveillance to fully understand potential adverse effects.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[COVID-19 vaccine safety]. Chaparro Mérida, NA., Moreno Samper, D., Lacato, AOF.[2022]

The intranasal CVXGA1 vaccine, which uses a parainfluenza virus vector, has shown strong efficacy in animal models by inducing neutralizing antibodies against multiple SARS-CoV-2 variants and protecting against both homologous and heterologous virus challenges.

When used as a booster after mRNA vaccines, CVXGA1 and other PIV5-vectored vaccines produced higher levels of cross-reactive neutralizing antibodies compared to three doses of mRNA vaccines, suggesting they could enhance protection against emerging variants.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy of Parainfluenza Virus 5 (PIV5)-vectored Intranasal COVID-19 Vaccine as a Single Dose Vaccine and as a Booster against SARS-CoV-2 Variants. Beavis, AC., Li, Z., Briggs, K., et al.[2023]

Citations

1. withpower.com withpower.com/trial/combination-vaccine-for-covid-19-and-flu-1e4bf

Combination Vaccine for COVID-19 and Flu The combination vaccine IIV-HD + rC19 is unique because it combines a high-dose influenza vaccine with the Spikevax COVID-19 mRNA vaccine, potentially offering ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC12031483/

Innovations, Challenges, and Future Prospects for ... For example, COVID-19 and influenza combination vaccines demonstrated good tolerance and immunogenicity, with dose adjustments resolving antigen ...

3. cidrap.umn.edu cidrap.umn.edu/covid-19/combo-flu-covid-vaccine-shows-good-immune-response-safety-older-adults

Combo flu-COVID vaccine shows good immune response, ... For all ages, mRNA-1083, the combined vaccine, elicited higher immune responses than the standard-dose flu vaccine given to those 50 to 64 years ...

4. gavi.org gavi.org/vaccineswork/dual-covid-19flu-shot-more-effective-individual-vaccines

Study suggest dual COVID-19/flu shot is more effective ... A combined mRNA vaccine against COVID-19 and seasonal influenza appears to trigger stronger immune responses against both viruses compared to ...

5. researchgate.net researchgate.net/publication/390063474_Innovations_Challenges_and_Future_Prospects_for_Combination_Vaccines_Against_Human_Infections

(PDF) Innovations, Challenges, and Future Prospects for ... Moderna Announces Positive Phase 3 Data for Combination Vaccine Against Influenza and COVID-19. 2024. Available online: https://investors.

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8662238/

Comparative safety of mRNA COVID‐19 vaccines to influenza ... mRNA COVID-19 vaccines had more systematic reactions, and a higher risk of some cardiovascular issues, but lower risk of neurological issues compared to ...

7. fda.gov fda.gov/vaccines-blood-biologics/spikevax

Spikevax SPIKEVAX is a COVID-19 mRNA vaccine for active immunization, approved for those 65+, or 6 months-64 with high-risk conditions.

8. cdc.gov cdc.gov/acip/downloads/slides-2025-09-18-19/06-el-deiry-kuperwasser-covid-508.pdf

Workgroup Safety Uncertainties of mRNA COVID Vaccines COVID-19 vaccine safety concerns stem from unexpected biological activities of mRNA gene therapy platforms, raising questions about ...