Evaluation of the Safety and Immunogenicity of Influenza and COVID-19 Combination Vaccine

This is a randomized, observer-blinded, Phase 1/2 study evaluating the safety and immunogenicity of a quadrivalent HA nanoparticle influenza and SARS-CoV-2 rS nanoparticle combination vaccine with Matrix-M1 adjuvant; this combination is referred to as ICC vaccine.

This is a randomized, observer-blinded, Phase 1/2 study evaluating the safety and immunogenicity of a quadrivalent hemagglutinin (HA) nanoparticle influenza vaccine (qNIV) and severe acute respiratory syndrome coronavirus 2 (SARSCoV2) recombinant spike (rS) nanoparticle combination vaccine with Matrix-M1™ adjuvant; this combination vaccine is referred to as Influenza COVID-19 Combination (ICC) vaccine.

The study will enroll approximately 640 healthy (based on history and physical examination) adult male and female participants 50 to 70 years of age, inclusive, targeting participants who are baseline seropositive (either previously infected with SARS-CoV-2 ≥ 8 weeks prior to enrollment, or have been previously immunized against SARS-CoV-2 with a completed regimen of an authorized vaccine at ≥ 8 weeks prior to enrollment). Randomization will be stratified on age ≥ 50 to ≤60 or

≥ 60 to ≤ 70 years to distribute the proportions of each age stratum evenly across vaccine groups.

Eligibility Criteria:
Inclusion Criteria:

1. Healthy, medically stable adult males or females ≥ 50 to ≤ 70 years of age at screening.
2. Willing and able to give informed consent prior to study enrollment.
3. Able to attend study visits, comply with study requirements, and provide reliable and complete reports of AEs.
4. Participants must have been baseline seropositive to SARS-CoV-2 defined as either:

   • Having completed a primary vaccination series against SARS-CoV-2 with an authorized COVID-19 vaccine with receipt of second/final dose of authorized vaccine ≥ 8 weeks prior to enrollment (first study vaccination).

   OR

   • Previously infected with SARS CoV-2 ≥ 8 weeks prior to enrollment (first study vaccination).

   Note: Baseline SARS-CoV-2 serostatus determination at screening will be based on vaccination documentation (eg, vaccination card or vaccination registry) or participants' report of a previous SARS-CoV-2 infection.
5. Women of childbearing potential (defined as any female participant 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 the study OR agree to consistently use a medically acceptable method of contraception listed below from at least 28 days prior to enrollment and through the end of the study.

   1. Condoms (male or female) with spermicide (if acceptable in-country)
   2. Diaphragm with spermicide
   3. Cervical cap with spermicide
   4. Intrauterine device
   5. Oral or patch contraceptives
   6. Norplant®, Depo-Provera®, or other in-country regulatory approved contraceptive method that is designed to protect against pregnancy
   7. Abstinence, as a form of contraception, is acceptable if in line with the participant's lifestyle
6. Participants must be healthy and medically stable, as determined by the investigator (based on a review of health status, vital signs \[to include body temperature\], medical history, and targeted physical examination \[to include body weight\]). Participants must have a body mass index (BMI) of 17 to 34 kg/m2, inclusive, at screening. Vital signs must be within medically acceptable ranges prior to the first vaccination.
7. Participants must agree to not participate in any other SARS-CoV-2 or influenza prevention or treatment studies for the duration of the study. Note: For participants who become hospitalized with COVID-19, participation in investigational treatment studies is permitted.

Exclusion Criteria:

1. Any ongoing, symptomatic acute, or chronic illness requiring medical or surgical care.

   * Asymptomatic chronic conditions or findings (eg, mild hypertension, dyslipidemia) that are not associated with evidence of end-organ damage are not exclusionary provided that they are being appropriately managed and are clinically stable (ie, unlikely to result in symptomatic illness within the time-course of this study), in the opinion of the investigator.
   * Acute or chronic illnesses or conditions which may be reasonably predicted to become symptomatic if treatment were withdrawn or interrupted are exclusionary, even if stable.
   * Acute or chronic illnesses reasonably expected to be associated with increased risks in the event of influenza or SARS-CoV-2 infection (eg, cardio-pulmonary diseases, diabetes mellitus, renal or hepatic dysfunction, hemoglobinopathies) are exclusionary, even if stable.
2. Participation in research involving an investigational product (drug/biologic/device) within 90 days before the planned date of the first injection.
3. Use of COVID-19 prophylactic or treatment monoclonal antibodies or antibody cocktails within 90 days prior to the planned date of the first injection.
4. History of a serious reaction to prior influenza vaccination or known allergy to constituents of influenza vaccines - including egg proteins - or polysorbate 80; or any known allergies to products contained in the investigational product.
5. Any history of anaphylaxis to any prior vaccine.
6. History of Guillain-Barré Syndrome within 6 weeks following a previous influenza vaccine.
7. Receipt of any vaccine in the 4 weeks preceding the study vaccination and any influenza vaccine within 2 months preceding the study vaccination. Note: Routine vaccinations will not be allowed until after study Day 70.
8. Any known or suspected autoimmune or immunosuppressive illness, congenital or acquired, based on medical history and/or physical examination.
9. Chronic administration (defined as more than 14 continuous days) of immunosuppressants or other immune-modifying drugs within 6 months prior to the administration of the study vaccines. An immunosuppressant dose of glucocorticoid will be defined as a systemic dose ≥ 10 mg of prednisone per day or equivalent. The use of topical, inhaled, and nasal glucocorticoids will be permitted.
10. Administration of immunoglobulins and/or any blood products within the 3 months preceding the administration of the study vaccine or during the study.
11. Active cancer (malignancy) therapy within 3 years prior to first 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).
12. Participants who are breastfeeding, pregnant, or who plan to become pregnant prior to the EoS.
13. Known disturbance of coagulation.
14. Suspected or known history of alcohol abuse or drug addiction within 2 years prior to the first trial vaccine dose that, in the opinion of the investigator, might interfere with protocol compliance.
15. Acute disease at the time of enrollment (defined as the presence of a moderate or severe illness with or without fever, or an oral temperature \> 38.0°C, on the planned day of vaccine administration).
16. Any 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 vaccine or interpretation of study results (including neurologic or psychiatric conditions deemed likely to impair the quality of safety reporting).
17. Study team member or immediate family member of any study team member (inclusive of Sponsor, Contract Research Organization, and study site personnel involved in the conduct or planning of the study).