Please select the eligibility criteria that correspond to the clinical trial below.
Title: A Randomized, Observer-blind, Multicenter, Phase 3 Study to Evaluate the Lot Consistency, Immunogenicity, and Safety of a Plant-Derived Quadrivalent VLP Influenza Vaccine in Healthy Adults 18-49 Years of Age
Brief Summary: This Phase 3 study is intended to assess the clinical lot-to-lot consistency in manufacturing by evaluating and comparing the immunogenicity of three consecutively manufactured lots of the Quadrivalent Virus-Like Particles (VLP) Influenza Vaccine, during the 2016-2017 influenza season, in healthy adults 18-49 years of age. A single dose of one of three consecutive lots of Quadrivalent VLP Influenza Vaccine (30 µg/strain) will be administered to 1,200 participants.


Options:
A: Inclusion Criteria:

Participants must meet all of the following inclusion criteria to be eligible for participation in this study; no protocol waivers are allowed:

1. Participants must be considered by the Investigator to be reliable and likely to cooperate with the assessment procedures and be available for the duration of the study;
2. Participants have a body mass index (BMI) ≤ 40.0 kg/m\^2 on Day 0 (pre-vaccination);
3. Participants must be in good general health prior to study participation with no clinically relevant abnormalities that could jeopardize participant safety or interfere with study assessments as assessed by the Principal Investigator or sub-Investigator (thereafter referred as Investigator) and determined by medical history, physical examination, and vital signs; Note: Participants with a pre-existing chronic disease will be allowed to participate if the disease is stable and, according to the Investigator's judgment, the condition is unlikely to confound the results of the study or pose additional risk to the participant by participating in the study. Stable disease is generally defined as no new onset or exacerbation of pre-existing chronic disease six months prior to vaccination. Based on the Investigator's judgment, a participant with a more recent stabilization of a disease could also be eligible.
4. Female participants must have a negative urine pregnancy test result at the Screening/Vaccination visit (Visit 1);
5. Female participants of childbearing potential must use an effective method of contraception for one month prior to vaccination and agree to continue employing adequate birth control measures for the duration of the study. Abstinent participants should be asked what method(s) they would use, should their circumstances change, and participants without a well-defined plan should be excluded. The following relationship or methods of contraception are considered to be effective:

   * Hormonal contraceptives (e.g. oral, injectable, topical \[patch\], or estrogenic vaginal ring);
   * Intra-uterine device with or without hormonal release;
   * Male partner using a condom plus spermicide or a sterilized partner (at least one year prior to vaccination);
   * Credible self-reported history of heterosexual vaginal intercourse abstinence until at least the Day 21 visit;
   * Female partner.
6. Non-childbearing females are defined as:

   * Surgically-sterile (defined as bilateral tubal ligation, hysterectomy, or bilateral oophorectomy performed more than one month prior to vaccination); or
   * Post-menopausal (absence of menses for 24 consecutive months and age consistent with natural cessation of ovulation).

Exclusion Criteria:

Participants who meet any of the following criteria will be excluded from participating in this study; no protocol waivers are allowed:

1. According to the Investigator's opinion, history of significant acute or chronic, uncontrolled medical or neuropsychiatric illness. 'Uncontrolled' is defined as:

   * Requiring a new medical or surgical treatment during the six months prior to study vaccine administration unless the criteria outlined in inclusion criterion no. 3 can be met (i.e. the Investigator can justify inclusion based upon the innocuous nature of medical/surgical events and/or treatments);
   * Requiring any significant change in a chronic medication (i.e. drug, dose, frequency) during the three months prior to study vaccine administration due to uncontrolled symptoms or drug toxicity, unless the innocuous nature of the medication change meets the criteria outlined in inclusion criterion no. 5 and is appropriately justified by the Investigator.
2. Any medical or neuropsychiatric condition or any history of excessive alcohol use or drug abuse which, in the Investigator's opinion, would render the participant unable to provide informed consent or unable to provide valid safety observations and reporting;
3. Any autoimmune disease other than hypothyroidism with stable replacement therapy; or any confirmed or suspected immunosuppressive condition or immunodeficiency including known or suspected human immunodeficiency virus (HIV), hepatitis B or C infection, or the presence of lymphoproliferative disease;
4. Administration or planned administration of any non-influenza vaccine within 30 days prior to randomization and up to blood sampling on Day 21. Immunization on an emergency basis will be evaluated case-by-case by the Investigator;
5. Administration of any adjuvanted or investigational influenza vaccine within 24 months prior to randomization or planned administration prior to the completion of Day 21;
6. Administration of any "standard", non-adjuvanted influenza vaccine (e.g. live attenuated trivalent/quadrivalent inactivated influenza vaccine intranasal or split trivalent/quadrivalent inactivated influenza vaccine by either intradermal or IM route) within 24 months prior to randomization and up to completion of the Day 21 visit;
7. Use of any investigational or non-registered product within 30 days prior to randomization or planned use during the study period. Participants may not participate in any other investigational or marketed drug study while participating in this study until the Day 21 visit. Participation in observational studies is permitted;
8. Treatment with systemic glucocorticoids at a dose exceeding 10 milligrams (mg) of prednisone (or the equivalent) per day for more than seven consecutive days or for ten or more days in total, within one month of study vaccine administration; or any other cytotoxic or immunosuppressant drug, or any immunoglobulin preparation within three months of vaccination and until the completion of the Day 21 visit. Low doses of nasal or inhaled glucocorticoids and topical steroids are permitted;
9. Any significant disorder of coagulation including, but not limited to, treatment with warfarin derivatives or heparin. Persons receiving prophylactic anti-platelet medications (e.g. low-dose aspirin \[no more than 325 mg/day\]) and without a clinically apparent bleeding tendency are eligible. Participants treated with new generation drugs that do not increase the risk of IM bleeding (e.g. clopidogrel) are also eligible.
10. History of allergy to any of the constituents of the Quadrivalent VLP Influenza Vaccine or a tobacco allergy;
11. History of anaphylactic allergic reactions to plants or plants components;
12. Any history of serious asthma (e.g. status asthmaticus, hospitalization for asthma control) in the last three years;
13. Use of antihistamines 48 hours prior to study vaccination;
14. The use of prophylactic medications (e.g. acetaminophen/paracetamol, aspirin, naproxen, or ibuprofen) within 24 hours of randomization to prevent or pre-empt symptoms due to vaccination. Participant discovered to have taken a prophylactic medication to prevent or pre empt symptoms due to vaccination within the 24 hours prior to planned randomization must be delayed until at least the 24-hour period is met;
15. Participants who have a dermatological condition at the injection site that may interfere with injection site reaction rating;
16. Participant who have received a blood transfusion within 90 days prior to study vaccination;
17. Any female participant who has a positive or doubtful pregnancy test result prior to vaccination or who is lactating;
18. Presence of any febrile illness (including oral temperature (OT) ≥ 38.0 ˚C within 24 hours prior to vaccination). Such participants may be re-evaluated for enrolment after resolution of illness;
19. Cancer or treatment for cancer within three years of study vaccine administration. Participants with a history of cancer who are disease-free without treatment for three years or more are eligible. Individuals with treated and uncomplicated basal cell carcinoma of the skin or with non-treated, non-disseminated local prostate cancer are eligible;
20. Participants identified as an Investigator or employee of the Investigator or clinical site with direct involvement in the proposed study, or identified as an immediate family member (i.e. parent, spouse, natural or adopted child) of the Investigator or employee with direct involvement in the proposed study or any employee of Medicago. Immediate family members of the Investigator or employees of a clinical site can participate in the study at another clinical site, as long as the Investigator or employees are not involved in the study at that site;
21. Participant with a history of Guillain-Barré syndrome.
B: Inclusion Criteria:

For Part 1A, Part 2 and Part 3:

* Participants 12 to \<18 years of age at the time of consent (Screening Visit, Day 0) who, in the opinion of the Investigator, are in good general health based on review of medical history and screening physical examination.
* Investigator assessment that the participant, in the case of an emancipated minor, or parent(s)/legally acceptable representative(s) (LAR\[s\]) understand and is willing and physically able to comply with protocol-mandated follow up, including all procedures and provides written informed consent/assent.
* Body mass index (BMI) at or above the third percentile according to World Health Organization (WHO) Child Growth Standards at the Screening Visit (Day 0)
* Female participants of nonchildbearing potential may be enrolled in the study. Nonchildbearing potential is defined as premenarche or surgically sterile (history of bilateral tubal ligation, bilateral oophorectomy, hysterectomy).
* Female participants of childbearing potential may be enrolled in the study if the participant has a negative pregnancy test at Screening (Day 0), on the day of the first injection (Day 1), on the day of the second injection (Day 29 in Parts 1A and Part 2, and Day 181 in Part 3); has practiced adequate contraception or has abstained from all activities that could result in pregnancy for at least 28 days prior to the first injection (Day 1); and has agreed to continue adequate contraception or abstinence through 3 months following the second injection (Day 29 in Part 1A and Part 2, and Day 181 in Part 3).

For Part 1B:

* Participants must have been previously enrolled in mRNA-1273-P203 study.
* Female participants of childbearing potential may be enrolled in the study if the participant has a negative pregnancy test on the day of the first injection (Open-Label-Day 1) and on the day of the second injection (Open-Label-Day 29).

For Part 1C-1 Homologous Booster Dose:

* Participants must have been previously enrolled in the mRNA-1273-P203 study, are actively participating in Part 1A or Part 1B and are least 5 months from the last dose.
* Female participants of childbearing potential may be enrolled in the study if the participant has a negative pregnancy test on the day of the first injection (BD-Day 1).

Part 1C-2 Heterologous Booster Dose:

* Male or female, 12 to \< 18 years of age at the time of consent who, in the opinion of the investigator, is in good general health based on review of medical history and screening physical examination AND has completed non-Moderna primary COVID-19 vaccination series under EUA (for example, Pfizer) at least 3 months from consent.

Exclusion Criteria:

For Part 1A, Part 2, and Part 3:

* Has a known history of SARS-CoV-2 infection within 2 weeks prior to administration of investigational product (IP) or known close contact with anyone with laboratory-confirmed SARS-CoV-2 infection of COVID-19 within 2 weeks prior to administration of IP (Part 2 participants only). For Part 3 participants, known history of SARS-CoV-2 infection within 90 days prior to administration of IP or known close contact with anyone with laboratory-confirmed SARS-CoV-2 infection or COVID-19 within 90 days prior to administration of IP.
* Travel outside of the United States or home country (Part 2 and Part 3 only) in the 28 days prior to the Screening Visit (Day 0).
* Pregnant or breastfeeding
* Is acutely ill or febrile 24 hours prior to or at the Screening Visit (Day 0). Fever is defined as a body temperature ≥38.0°Celsius (C)/≥100.4°Farenheit (F). Participants who meet this criterion may have visits rescheduled within the relevant study visit windows. Afebrile participants with minor illnesses can be enrolled at the discretion of the Investigator.
* Prior administration of an investigational coronavirus (for example, SARS-CoV-2, SARS-CoV, Middle East Respiratory Syndrome \[MERS-CoV\]) vaccine
* Current treatment with investigational agents for prophylaxis against COVID-19
* Has a medical, psychiatric, or occupational condition that may pose additional risk as a result of participation, or that could interfere with safety assessments or interpretation of results according to the Investigator's judgment
* Current use of any inhaled substance (for example, tobacco or cannabis smoke, nicotine vapors)
* History of chronic smoking (≥1 cigarette a day) within 1 year of the Screening Visit (Day 0)
* History of illegal substance use or alcohol abuse within the past 2 years. This exclusion does not apply to historical cannabis use that was formerly illegal in the participant's state but is legal at the time of screening.
* History of a diagnosis or condition that, in the judgment of the Investigator, may affect study endpoint assessment or compromise participant safety, specifically:

  * Congenital or acquired immunodeficiency, including human immunodeficiency virus (HIV) infection
  * Suspected active hepatitis
  * Has a bleeding disorder that is considered a contraindication to IM injection or phlebotomy
  * Dermatologic conditions that could affect local solicited AR assessments
  * History of anaphylaxis, urticaria, or other significant AR requiring medical intervention after receipt of a vaccine
  * Diagnosis of malignancy within the previous 10 years (excluding nonmelanoma skin cancer)
  * Febrile seizures
* Receipt of:

  * Any licensed vaccine within 28 days before the first dose of IP or plans for receipt of any licensed vaccine within 28 days before and/or after each dose of IP.
  * Systemic immunosuppressants or immune-modifying drugs for \>14 days in total within 6 months prior to the day of enrollment (for corticosteroids, ≥20 mg/day prednisone equivalent). Topical tacrolimus is allowed if not used within 14 days prior to the day of enrollment. Participants may have visits rescheduled for enrollment if they no longer meet this criterion within the Screening Visit window. Inhaled, nasal, and topical steroids are allowed.
  * Intravenous blood products (red cells, platelets, immunoglobulins) within 3 months prior to enrollment
* Has donated ≥450 milliliters (mL) of blood products within 28 days prior to the Screening Visit (Day 0) or plans to donate blood products during the study
* Participated in an interventional clinical study within 28 days prior to the Screening Visit (Day 0) or plans to do so while participating in this study
* Is an immediate family member or has a household contact who is an employee of the research center or otherwise involved with the conduct of the study

For Part 1C-1 and Part 1C-2:

* Pregnant or breastfeeding.
* Is acutely ill or febrile 24 hours prior to or at the Screening Visit (Day 0). Fever is defined as a body temperature ≥ 38.0°C/≥ 100.4°F. Participants who meet this criterion may have visits rescheduled within the relevant study visit windows. Afebrile participants with minor illnesses can be enrolled at the discretion of the investigator.
* Has a medical, psychiatric, or occupational condition that may pose additional risk as a result of participation, or that could interfere with safety assessments or interpretation of results according to the investigator's judgment.
* History of a diagnosis or condition (after enrolment in Part 1A) that, in the judgment of the investigator, may affect study endpoint assessment or compromise participant safety:

  * Suspected active hepatitis
  * Has a bleeding disorder that is considered a contraindication to IM injection or phlebotomy
  * Dermatologic conditions that could affect local solicited AR assessments
  * History of anaphylaxis, urticaria, or other significant AR requiring medical intervention after receipt of a vaccine
  * Diagnosis of malignancy (excluding nonmelanoma skin cancer)
* Receipt of:

  • Any authorized or licensed vaccine within 28 days before the first dose of IP or plans for receipt of any licensed vaccine through 28 days following the last dose of IP or any seasonal influenza vaccine within 14 days before the first dose of IP or plans for receipt of any seasonal influenza vaccine 14 days following the last dose of IP.
* Participated in an interventional clinical study, other than mRNA-1273-P203 study, within 28 days prior to the Screening Visit (Day 0 \[for Part 1C-1\], BD-Day 0 \[for Part 1C-2\]) or plans to do so while participating in this study.

Part 1C-2 Heterologous Booster Dose:

* Has a known history of SARS-CoV-2 infection within 2 weeks prior to administration of IP or known close contact with anyone with laboratory-confirmed SARS-CoV-2 infection or COVID 19 within 2 weeks prior to administration of IP.
C: Inclusion Criteria:

* Phase Ia:

  1. Healthy adults aged 18 to 59 years (including boundary values), both men and women.
  2. Proven legal identity.
  3. Participants should understand the contents of the informed consent form, the vaccine in this trial, voluntarily sign the informed consent form, and be capable of using thermometers, scales, and filling in diary cards and contact cards as required.
  4. Participants should be able to communicate well with investigators, understand and comply with the requirements of this trial.
  5. Axillary temperature ≤37.0 ℃.
* Phase IIa:

  1. Healthy adults aged 18 to 59 years (including boundary values), both men and women.
  2. Proven legal identity.
  3. Participants should understand the contents of the informed consent form, the vaccine in this trial, voluntarily sign the informed consent form, and be capable of using thermometers, scales, and filling in diary cards and contact cards as required.
  4. Participants should be able to communicate well with investigators, understand and comply with the requirements of this trial.
  5. Axillary temperature ≤37.0 ℃.

Exclusion Criteria:

* Phase Ia:

  1. Contraindications for vaccination.
  2. History of allergy to vaccines or drugs.
  3. Immunization with any vaccine within 1 month.
  4. History of abnormal clinical manifestations and serious diseases to be excluded, including but not limited to nervous system, cardiovascular system, blood and lymphatic system, immune system, kidney, liver, gastrointestinal tract, respiratory system, metabolism, bones and other system diseases, and a history of malignant tumors.
  5. Those who developed acute disease within 2 weeks, or had symptoms of fever or upper respiratory tract infection within 7 days.
  6. Those who have a hereditary bleeding tendency or coagulation dysfunction, or a history of thrombosis or bleeding disorders.
  7. Those who cannot tolerate venipuncture, or have a history of halo needles or halo blood.
  8. Surgical removal of spleen or other important organs for any reason.
  9. Those who have undergone surgery within 3 months before signing the informed consent, or those who plan to perform surgery during the trial or within 3 months after the end of the trial (including cosmetic surgery, dental and oral surgery).
  10. Those who donated or lost blood (≥400 mL) in the past 3 months, who received blood transfusion or use of blood products, or who planned blood donation during the trial.
  11. Receipt of other investigational or unregistered products (drugs, vaccines, biological product or devices) in the past 3 months, or plan to use other investigational or unregistered products during the study.
  12. Receipt of immunosuppressive therapy within 6 months before signing the informed consent form, such as long-term systemic glucocorticoid therapy (with systemic glucocorticoid therapy for more than 2 weeks within 6 months, such as prednisone or similar drugs) ), but local administration (such as ointment, eye drops, inhalation, or nasal spray) is allowed. The local administration should not exceed the dosage recommended in the instructions or have any signs of systemic exposure.
  13. Those who have took soft drugs (such as marijuana) within 3 months before signing the informed consent form or took hard drugs (such as: cocaine, phencyclidine, etc.) within 1 year before the trial.
  14. Those who smoked more than 5 cigarettes per day within 3 months before signing the informed consent form.
  15. The weekly drinking volume is greater than 14 units within 3 months before signing the informed consent form (1 unit alcohol approximately equal to 360 mL beer or 45 mL spirits with 40% alcohol content or 150 mL wine).
  16. The comprehensive physical examination does not meet the health standards, mainly including: (1) Those with abnormal vital signs with clinical significance. (2) BMI\<18 kg/m\^2 or\> 30 kg/m\^2. (3) Abnormal laboratory examination with clinical significance. (4) Those who tested positive for human immunodeficiency virus (HIV) antibody, hepatitis B surface antigen, hepatitis B e antigen, hepatitis C virus antibody, or Treponema pallidum antibody (tp-trust).
  17. Participants who have a positive pregnancy test, or are breastfeeding, or plan to become pregnant, or plan to donate sperm or eggs from the screening to 12 months after the second vaccination.
  18. Positive in drug abuse screening during the screening period (Morphine, Methamphetamine, Ketamine, MDMA and Tetrahydrocannabinolic acid).
  19. Positive in alcohol breath test during the screening period.
  20. Positive in SARS-CoV-2 nucleic acid screening or antibodies (IgG or IgM) screening.
  21. History of severe acute respiratory syndrome (SARS) or Middle East respiratory syndrome (MERS) or other coronavirus infection (HCoV-229E, HCoV-OC43, HCoV-NL63, HCoV-HKU1).
  22. History of contact with confirmed or suspected cases infected with SARS-CoV-2 within 1 month.
  23. Any other situations judged by investigators as not suitable for participating in this study.
* Phase IIa:

  1. Contraindications for vaccination.
  2. History of allergy to vaccines or drugs.
  3. Immunization with any vaccine within 1 month.
  4. History of abnormal clinical manifestations and serious diseases to be excluded, including but not limited to nervous system, cardiovascular system, blood and lymphatic system, immune system, kidney, liver, gastrointestinal tract, respiratory system, metabolism, bones and other system diseases, and a history of malignant tumors.
  5. Those who developed acute disease within 2 weeks, or had symptoms of fever or upper respiratory tract infection within 7 days.
  6. Those who have a hereditary bleeding tendency or coagulation dysfunction, or a history of thrombosis or bleeding disorders.
  7. Surgical removal of spleen or other important organs for any reason.
  8. Those who have undergone surgery within 3 months before signing the informed consent, or those who plan to perform surgery during the trial or within 3 months after the end of the trial (including cosmetic surgery, dental and oral surgery).
  9. Those who donated or lost blood (≥400 mL) in the past 3 months, who received blood transfusion or use of blood products, or who planned blood donation during the trial.
  10. Receipt of other investigational or unregistered products (drugs, vaccines, biological product or devices) in the past 3 months, or plan to use other investigational or unregistered products during the study.
  11. Receipt of immunosuppressive therapy within 6 months before signing the informed consent form, such as long-term systemic glucocorticoid therapy (with systemic glucocorticoid therapy for more than 2 weeks within 6 months, such as prednisone or similar drugs) ), but local administration (such as ointment, eye drops, inhalation, or nasal spray) is allowed. The local administration should not exceed the dosage recommended in the instructions or have any signs of systemic exposure.
  12. The comprehensive physical examination does not meet the health standards, mainly including: (1) Those with abnormal vital signs (Pulse \<55 beats per minute or\> 100 beats per minute at rest, Systolic blood pressure ≥140mmHg or Diastolic blood pressure ≥90mmHg, breathing\> 20 beats per minute or \<12 beats per minute). (2) Those who tested positive for human immunodeficiency virus (HIV) antibody, hepatitis B surface antigen, hepatitis B e antigen, hepatitis C virus antibody, or Treponema pallidum antibody (tp-trust).
  13. Participants who have a positive pregnancy test, or are breastfeeding, or plan to become pregnant, or plan to donate sperm or eggs from the screening to 12 months after the second vaccination.
  14. Positive in SARS-CoV-2 nucleic acid screening or antibodies (IgG or IgM) screening.
  15. History of severe acute respiratory syndrome (SARS) or Middle East respiratory syndrome (MERS) or other coronavirus infection (HCoV-229E, HCoV-OC43, HCoV-NL63, HCoV-HKU1).
  16. History of contact with confirmed or suspected cases infected with SARS-CoV-2 within 1 month.
  17. Any other situations judged by investigators as not suitable for participating in this study.
D: Inclusion Criteria (Part 1):

* Healthy adult males or females between 18 and 59 years of age, inclusive, at screening. Healthy status will be determined by the investigator based on medical history, clinical laboratory results, vital sign measurements, and physical examination at screening.
* The participant has a body mass index 17 to 35 kg/m2, inclusive, at screening.
* Willing and able to give informed consent prior to study enrollment and comply with study procedures.
* Female participants of childbearing potential (defined as any female who has experienced menarche and who is NOT surgically sterile \[ie, hysterectomy, bilateral tubal ligation, or bilateral oophorectomy\] or postmenopausal \[defined as amenorrhea at least 12 consecutive months or documented plasma follicle-stimulating hormone (FSH) level ≥40 mIU/mL\]) must agree to be heterosexually inactive from at least 21 days prior to enrollment and through 6 months after the last vaccination OR agree to consistently use any of the described methods of contraception from at least 21 days prior to enrollment and through 6 months after the last vaccination.

Exclusion Criteria (Part 1):

* Any ongoing, symptomatic acute or chronic illness requiring medical or surgical care, inclusive of changes in medication in the past 2 months indicating that chronic illness/disease is not stable (at the discretion of the investigator). This includes any current workup of undiagnosed illness that could lead to a new condition.
* Chronic disease inclusive of: a) hypertension uncontrolled for age according to the Eighth Joint National Committee (JNC 8) guidelines; b) congestive heart failure by New York Heart Association (NYHA) functional classification of greater or equal to II; c) chronic obstructive pulmonary disease by Global Initiative for Obstructive Lung Disease (GOLD) classification of greater or equal to 2; d) recent (within 6 months prior to first study vaccination) exacerbation of coronary artery disease as manifested by cardiac intervention, addition of new cardiac medications for control of symptoms, or unstable angina; e) asthma (diagnosed by spirometry showing reversibility of disease and must meet at least the Step 1 classification with current prescription/use of medications to control symptoms); f) diabetes requiring use of medicine (insulin or oral) or not controlled with diet.
* Participation in research involving an investigational product (drug/biologic/device) within 45 days prior to first study vaccination.
* History of a confirmed diagnosis of SARS or COVID-19 disease (confirmed by a specific test for each disease) or known exposure to a SARS-CoV-2 positive confirmed close contact (eg, family member, housemate, daycare provider, aged parent requiring care), at the discretion of the investigator.
* Currently working in an occupation with a high risk of exposure to SARS-CoV-2 (eg, healthcare worker, emergency response personnel).
* Currently taking any product (investigational or off-label) for prevention of COVID-19 disease.
* Positive rapid test for SARS-CoV-2 (either ELISA IgG or PCR) at screening or prior to first vaccination. Testing may be repeated during the screening period if exposure to SARS-CoV-2 is suspected, at the discretion of the investigator.
* Received influenza vaccination within 14 days prior to first study vaccination, or any other vaccine within 4 weeks prior to first study vaccination.
* Any autoimmune or immunodeficiency disease/condition (iatrogenic or congenital).
* Chronic administration (defined as more than 14 continuous days) of immunosuppressant, systemic glucocorticosteroids, or other immune-modifying drugs within 90 days prior to first study vaccination; or anticipation of the need for immunosuppressive treatment within 6 months after last vaccination.
* Received immunoglobulin, blood-derived products, or other immunosuppressant drugs within 90 days prior to first study vaccination.
* Any acute illness concurrent or within 14 days prior to first study vaccination (medical history and/or physical examination) or documented temperature of \>38°C during this period. This includes respiratory or constitutional symptoms consistent with SARS-CoV-2 (COVID-19) exposure (ie, cough, sore throat, difficulty breathing).
* Known disturbance of coagulation (iatrogenic or congenital).
* Evidence of Hepatitis B or C or HIV by laboratory testing.
* A positive test result for drugs of abuse (except a positive test result associated with prescription medication that has been reviewed and approved by the investigator) or alcohol at screening.
* Any neurological disease or history of significant neurological disorder (eg, meningitis, seizures, multiple sclerosis, vasculitis, migraines, Guillain-Barré syndrome \[genetic/congenital or acquired\]).
* Active cancer (malignancy) within 5 years prior to first study vaccination (with the exception of adequately treated non-melanomatous skin carcinoma, at the discretion of the investigator)
* Vital sign (blood pressure, pulse, temperature) abnormalities of toxicity grade \>1.
* Clinical laboratory abnormalities of toxicity grade \>1 for selected serum chemistry and hematology parameters
* Any known allergies to products contained in the investigational product or latex allergy.
* Women who are pregnant, breastfeeding or who plan to become pregnant during the study.
* History of alcohol abuse or drug addiction within 1 year prior to the first study vaccination.
* 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 study vaccine or interpretation of study results (including neurologic or psychiatric conditions deemed likely to impair the quality of safety reporting).
* Study team member or first-degree relative of any study team member (inclusive of sponsor, PPD, and site personnel involved in the study).

Inclusion Criteria (Part 2):

* Healthy adult males or females between 18 and 84 years of age, inclusive, at screening who are of legal adult age in their local jurisdiction. Healthy status will be determined by the investigator based on medical history, clinical laboratory results, vital sign measurements, and physical examination at screening.
* The participant has a body mass index 17 to 35 kg/m2, inclusive, at screening.
* Willing and able to give informed consent prior to study enrollment and comply with study procedures.
* Female participants of childbearing potential (defined as any female who has experienced menarche and who is NOT surgically sterile \[ie, hysterectomy, bilateral tubal ligation, or bilateral oophorectomy\] or postmenopausal \[defined as amenorrhea at least 12 consecutive months or documented plasma FSH level ≥40 mIU/mL\]) must agree to be heterosexually inactive from at least 21 days prior to enrollment and through 6 months after the last vaccination OR agree to consistently use any of the following methods of contraception from at least 21 days prior to enrollment and through 6 months after the last vaccination.

Exclusion Criteria (Part 2):

* Participants who are having any current workup of undiagnosed illness within the last 8 weeks, which is either participant-reported or has been clinician-assessed, that could lead to a new condition diagnosis.
* Participation in research involving an investigational product (drug/biologic/device) within 45 days prior to first study vaccination.
* History of a confirmed diagnosis of SARS or history of a confirmed diagnosis of COVID-19 disease resulting in medical intervention.
* Received influenza vaccination within 14 days prior to first study vaccination, or any other vaccine within 4 weeks prior to first study vaccination.
* Have clinically significant chronic cardiovascular, endocrine, gastrointestinal/ hepatic, renal, neurological, respiratory, or other medical disorders not excluded by other exclusion criteria, that are assessed by the Investigator as being clinically unstable within the prior 4 weeks evidenced by: a) hospitalization for the condition, including day surgical interventions, b) new significant organ function deterioration, c) needing addition of new treatments or major dose adjustments of current treatments.
* Diabetes mellitus requiring insulin therapy (either type 1 or type 2 diabetes mellitus).
* Chronic obstructive pulmonary disease with a history of an acute exacerbation of any severity in the prior year.
* Any history of congestive heart failure.
* Any history of chronic kidney disease (the presence of impaired or reduced kidney function lasting at least 3 months). Clinical validation of potential cases of chronic kidney disease should be conducted.
* Evidence of unstable coronary artery disease as manifested by cardiac intervention, addition of new cardiac medications for control of symptoms, or unstable angina in the past 3 months.
* History of chronic neurological disorders that have required prior specialist physician review for diagnosis and management (such as multiple sclerosis, dementia, transient ischemic attacks, Parkinson's disease, degenerative neurological conditions, neuropathy, and epilepsy) or a history of stroke or previous neurological disorder within 12 months with residual symptoms. Participants with a history of migraine or chronic headaches or nerve root compression that have been stable on treatment for the last 4 weeks are not excluded.
* Any autoimmune or immunodeficiency disease/condition (iatrogenic or congenital).
* Chronic administration (defined as more than 14 continuous days) of immunosuppressants, systemic glucocorticosteroids reaching an immunosuppressive dose, or other immune-modifying drugs within 90 days prior to first study vaccination.
* Received immunoglobulin, blood-derived products, or other immunosuppressant drugs within 90 days prior to first study vaccination.
* Known disturbance of coagulation (iatrogenic or congenital).
* Active cancer (malignancy) within 5 years prior to first study vaccination (with the exception of adequately treated non-melanomatous skin carcinoma, at the discretion of the investigator).
* Any known allergies to products contained in the investigational product or latex allergy.
* Women who are breastfeeding or who plan to become pregnant during the study.
* History of alcohol abuse or drug addiction within one year prior to the first study vaccination.
* Any condition that, in the opinion of the investigator, would pose a health risk to the subject if enrolled or could interfere with evaluation of the study vaccine or interpretation of study results (including neurologic or psychiatric conditions deemed likely to impair the quality of safety reporting).
* Study team member or first-degree relative of any study team member (inclusive of sponsor, PPD, and site personnel involved in the study).

Answer: A