Efficacy of a Plant-derived Quadrivalent VLP Vaccine in the Elderly

This randomized, observer-blind, placebo-controlled multicenter, Phase 3 study will be
conducted at multiple sites. The composition of the Quadrivalent VLP Influenza Vaccine to be
used in this study includes a mix of recombinant H1, H3, and two B hemagglutinin proteins
expressed as VLPs for the 2018-2019 influenza virus strains.

Approximately 12,120 healthy male and female subjects aged 65 years and older will be
randomized in a 1:1 ratio into one of two parallel treatment groups, such that approximately
6,060 subjects will receive the Quadrivalent VLP Influenza Vaccine at a dose of 30 μg/strain
and approximately 6,060 subjects will receive the comparator. Within the two treatment
groups, subjects will be stratified by site and two age groups (65-74 years of age and 75
years of age and older in a 2:1 ratio).

Subjects will participate in this study for approximately eight to ten months, during which a
first visit will be scheduled on Day 0 for screening and vaccine administration.

Inclusion Criteria:

1. Subjects must have read, understood, and signed the informed consent form (ICF) prior
to participating in the study; subjects must also complete study-related procedures
and communicate with the study staff at visits and by phone during the study;

2. Subject must have a body mass index (BMI) ≤ 35 kg/m2;

3. Subjects are considered by the Investigator to be reliable and likely to cooperate
with the assessment procedures and be available for the duration of the study;

4. Male and female subjects must be 65 years of age and older at the
Screening/Vaccination visit (Visit 1);

5. Subjects must be non-institutionalized (e.g. not living in rehabilitation centres or
old-age homes; living in an elderly community is acceptable) and have no acute or
evolving medical problems prior to study participation and no clinically relevant
abnormalities that could jeopardize subject 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: Subjects 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 subject by
participating in the study. Stable disease is generally defined as no new onset or
exacerbation of pre-existing chronic disease three months prior to vaccination. Based on
the Investigator's judgment, a subject with more recent stabilization of a disease could
also be eligible.

Exclusion Criteria:

1. According to the Investigator's opinion, history of an ongoing acute or evolving
medical or neuropsychiatric illness. 'Evolving' is defined as:

- Requiring a new medical or surgical treatment during the three months prior to
study vaccine administration unless the criteria outlined in inclusion criterion
no. 5 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 that would render the subject unable to provide informed consent or unable
to provide valid safety observations and reporting, including methadone (methadone as
treatment for opioid dependence may be acceptable if the subject has been otherwise
opioid-free for at least three years);

3. Any autoimmune disease other than hypothyroidism on stable replacement therapy
(including, but not limited to rheumatoid arthritis, systemic lupus erythematosus,
Crohn's disease, type 1 diabetes, and inflammatory bowel disease) or any confirmed or
suspected immunosuppressive condition or immunodeficiency including known or suspected
human immunodeficiency virus (HIV), Hepatitis B or C infection, the presence of
lymphoproliferative disease;

4. Any history of status asthmaticus or ongoing serious problems with asthma,
hospitalization for asthma control, or recurrent asthma episodes requiring medical
attention in the last three years (one or more episodes per year);

5. Administration or planned administration of any non-influenza vaccine within 30 days
prior to randomization up to blood sampling on Day 21. Immunization on an emergency
basis will be evaluated case-by-case by the Investigator;

6. Administration of any adjuvanted or investigational influenza vaccine within one year
prior to randomization or planned administration prior to the completion of the study;

7. Administration of any 'standard', non-adjuvanted influenza vaccine (e.g. live
attenuated trivalent/quadrivalent inactivated influenza vaccine or split
trivalent/quadrivalent inactivated influenza vaccine administered by intranasal,
intradermal, or intramuscular [IM] route) within six months prior to randomization and
up to completion of the study;

8. Use of any investigational or non-registered product within 30 days or five
half-lives, whichever is longer, prior to randomization or planned use during the
study period. Subjects may not participate in any other investigational or marketed
drug study while participating in this study until after the study;

9. Treatment with systemic glucocorticoids at a dose exceeding 10 mg of prednisone (or
equivalent) per day for more than seven consecutive days or for ten or more days in
total, within one month of study vaccine administration; any other cytotoxic or
immunosuppressant drug, or any immunoglobulin preparation within three months of
vaccination and until the completion of the study. Low doses of nasal or inhaled
glucocorticoids are allowed. Topical steroids are permitted;

10. 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 100 mg/day]), and without a
clinically apparent bleeding tendency are eligible. Subjects treated with new
generation drugs that do not increase the risk of IM bleeding (e.g. clopidogrel) are
also eligible;

11. History of allergy to any of the constituents of the Quadrivalent VLP Influenza
Vaccine, any components of the active comparator quadrivalent vaccine, or tobacco;

12. History of anaphylactic allergic reactions to plants or plants components (including
fruits and nuts);

13. Use of antihistamines within 48 hours prior to study vaccination;

14. Daily use of large doses of medication for pain control or inflammation (e.g. opioids,
nonsteroidal anti-inflammatory drugs [NSAIDs]). Use of a singular regular dose either
in the morning or at bedtime would not be exclusionary;

15. 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;

16. Planned use of influenza antiviral treatment medication before the collection of NP
swabs (e.g. oseltamivir, zanamivir, rapivab);

17. Have a rash, dermatological condition, tattoos, muscle mass, or any other
abnormalities at the injection site that may interfere with injection site reaction
rating;

18. Subjects who have received a blood transfusion within 90 days prior to study
vaccination;

19. Subjects with abnormal vital signs (systolic blood pressure [BP] ≥ 150 mmHg and/or
diastolic BP ≥ 95 mmHg for individuals taking antihypertensive medication and ≥ 140
mmHg and/or diastolic BP ≥ 90 mmHg for individuals not taking antihypertensive
medication; heart rate [HR] ≤ 45 beats/min and ≥ 100 beats/min) evaluated by an
Investigator to be clinically significant. A subject with abnormal vital signs results
may be included in the study based on Investigator's judgment (e.g. a resting HR ≤ 45
in highly trained athletes);

20. Presence of any febrile illness (including an oral temperature [OT] ≥ 38.0 ˚C within
24 hours prior to vaccination;

21. Cancer or treatment for cancer within three years prior to study vaccine
administration. Persons with a history of cancer who are disease-free without
treatment for three years or more are eligible. However, individuals with conditions
such as treated and uncomplicated basal cell carcinoma of the skin or non-treated,
non-disseminated local prostate cancer may be eligible;

22. Subjects 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) of the Investigator or any employee of Medicago
(or their family members);

23. Subjects with a history of Guillain-Barré Syndrome.