The purpose of this study is to collect serum samples to evaluate serologic assays and to establish proficiency panels for serologic assays used for assessment of post vaccination immune response after intramuscular (IM) vaccination with Norovirus GI.1/GII.4 bivalent virus-like particle (VLP) vaccine.

The vaccine being tested in this study is called Norovirus GI.1/GII.4 bivalent Virus-Like Particle Vaccine (NoV Vaccine). The purpose of this study is to collect serum samples to evaluate serologic assays and to establish proficiency panels for serologic assays used for assessment of post vaccination immune response after intramuscular (IM) vaccination with the NoV vaccine. The validation and proficiency testing of the immunogenicity assays is required to support the NoV Vaccine development program. This study also looked at side effects in people who were administered a single dose of the NoV vaccine.

The study enrolled 50 patients. All participants received one dose of the NoV vaccine via intramuscular injection.

Participants were asked to record any symptoms that may be related to the vaccine or the injection site in a diary card for 7 days after receiving the vaccination.

This single-centre trial was conducted in the United States. The overall time to participate in this study was 183 days. Participants made 4 visits to the clinic, and were contacted by telephone 183 days after last dose of study drug for a follow-up assessment.

Inclusion Criteria:

1. Age 18 to 49 years, inclusive.
2. Is in good health at the time of entry into the trial as determined by medical history, physical examination (including vital signs) and clinical judgment of the investigator.
3. Signs and dates a written, informed consent form and any required privacy authorization prior to the initiation of any trial procedures, after the nature of the trial has been explained according to local regulatory requirements.
4. Can comply with trial procedures and are available for the duration of follow-up.
5. Body weight of ≥50kg (110lbs).
6. Body mass index (BMI) <35.

Exclusion Criteria:

1. Has a history of acute gastroenteritis (AGE) within 14 days of enrollment.

2. Has previously been exposed to an experimental Norovirus (NoV) Vaccine.

3. Has received any inactivated vaccines within 14 days or any live vaccines for 28 days prior to enrollment in this trial or who are planning to receive any vaccine within 28 days of investigational vaccine administration.

4. Has contraindications, warnings and/or precautions to vaccination with the NoV Vaccine as specified within the investigator brochure.

5. Has known hypersensitivity or allergy to any of the NoV Vaccine components (including excipients).

6. Has behavioral or cognitive impairment or psychiatric disease that, in the opinion of the investigator, may interfere with the participant's ability to participate in the trial.

7. Has any history of progressive or severe neurologic disorder, seizure disorder or neuro-inflammatory disease (e.g. Guillain-Barré syndrome).

8. Has history or any illness that, in the opinion of the investigator, might interfere with the results of the trial or pose additional risk to the participants due to participation in the trial.

9. Has known or suspected impairment/alteration of immune function, including:

   1. Chronic use of oral steroids (Equivalent to 20 mg/day prednisone ≥ 12 weeks / ≥ 2 mg/kg body weight / day prednisone ≥ 2 weeks) within 60 days prior to Day 1 (use of inhaled, intranasal, or topical corticosteroids is allowed).
   2. Receipt of parenteral steroids (Equivalent to 20 mg/day prednisone ≥ 12 weeks / ≥ 2 mg/kg body weight / day prednisone ≥ 2 weeks) within 60 days prior to Day 1.
   3. Administration of immunoglobulins and/or any blood products within the three months preceding the first administration of the investigational vaccine or planned administration during the trial (consider whether applicable as an exclusion criterion or criterion for delay).
   4. Receipt of immunostimulants within 60 days prior to Day 1.
   5. Receipt of parenteral, epidural or intra-articular immunoglobulin preparation, blood products, and/or plasma derivates within 3 months prior to Day 1 or planned during the full length of the trial.
   6. Human immunodeficiency virus (HIV) infection or HIV-related disease.
   7. Genetic immunodeficiency.

10. Has abnormalities of splenic or thymic function.

11. Has a known bleeding diathesis, or any condition that may be associated with a prolonged bleeding time.

12. Has any serious chronic or progressive disease according to judgment of the investigator (e.g. neoplasm, insulin dependent diabetes, cardiac, renal or hepatic disease).

13. Is participating in any clinical trial with another investigational product 30 days prior to first trial visit or intent to participate in another clinical trial at any time during the conduct of this trial.

14. Is involved in the trial conduct or their first degree relatives.

15. Has history of substance or alcohol abuse within the past 2 years.

16. Females who are pregnant or breastfeeding.

17. If female of childbearing potential, sexually active, and has not used any of the "acceptable contraceptive methods" for at least 2 months prior to trial entry:

    1. Of childbearing potential is defined as status post onset of menarche and not meeting any of the following conditions: menopausal for at least 2 years, status after bilateral tubal ligation for at least 1 year, status after bilateral oophorectomy, or status after hysterectomy.
    2. Acceptable birth control methods are defined as one or more of the following:

    i. Hormonal contraceptive (such as oral, injection, transdermal patch, implant, cervical ring).

    ii. Barrier (condom with spermicide or diaphragm with spermicide) each and every time during intercourse.

    iii. Intrauterine device (IUD). iv. Monogamous relationship with vasectomized partner. Partner must have been vasectomized for at least six months prior to the participants' trial entry.

18. If female of childbearing potential and sexually active, refusal to use an "acceptable contraceptive method" through to 6 months after receipt of investigational vaccine. In addition, they must be advised not to donate ova during this period.

19. Any positive or indeterminate pregnancy test.

Safety Analysis Set, all participants who received the trial vaccine (NoV Vaccine).

Unsolicited AEs 28 days after vaccination (Day 1 to 28) and Serious Adverse Events (SAEs) throughout the trial (Up to Day 183).

At each visit the investigator documented any occurrence of AEs. Any event spontaneously reported by participant or observed by investigator was recorded, irrespective of relation to study treatment. Non-serious unsolicited AEs reported below. Non-serious solicited AEs reported in the outcome measure section.