Prevention From Norovirus Infection
Conditions
Brief summary
The purpose of this study is to determine whether the norovirus vaccine is effective in preventing acute gastroenteritis due to the experimental human Norovirus GII.4 challenge dose. The purpose is also to evaluate the safety of the vaccine and the immunogenicity of the vaccine.
Interventions
BIOLOGICALNorovirus Bivalent Vaccine
2 doses IM 28 days apart
BIOLOGICALSaline Comparator
2 doses IM 28 days apart
Sponsors
Takeda
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 49 Years
Healthy volunteers
Yes
Inclusion criteria
To be eligible to participate in this study, a subject must meet the following criteria: 1. Signed informed consent. 2. Age 18 to 50 years (e.g., not reached their 50th birthday). 3. Good general health as determined by a screening evaluation within 45 days of randomization. 4. Expressed interest, availability, and understanding to fulfill the study requirements including measures to prevent Norovirus contamination of the environment and spread of infection and illness to the community. The prospective subjects must pass (≥70 % correct answers) a written examination on all aspects of the study before enrollment. 5. Available to return for follow-up visits following discharge from the inpatient unit and able to deliver stool specimens to the investigative site promptly with no plan to move within the duration of the study. 6. Female subjects must be of non-childbearing potential, or if of childbearing potential (as determined by the investigator) must be practicing abstinence or using an effective licensed method of birth control (e.g. oral contraceptives; diaphragm or condom in combination with contraceptive jelly, cream, or foam; intrauterine contraceptive device, or Depo-Provera; skin patch; vaginal ring or cervical cap) for 30 days prior to vaccination and must agree to continue such precautions during the study and for 60 days after the Challenge visit. Male subjects must agree not to father a child from the day of vaccination until 60 days after the Challenge visit. 7. Have a serum antibody titer of ≤1:1600 to the GII.4 Norovirus challenge strain as measured by Immunoglobulin G (IgG) P Particle Enzyme-Linked Immunosorbent Assay (ELISA.) 8. Demonstrated to be H Type 1 secretor positive by Histoblood Group Antigen (HBGA) binding assay of their saliva test. \[This saliva test may be done at anytime prior to enrollment and does not need to be repeated.\] 9. Negative serology for hepatitis C antibody, Human Immune Deficiency Virus (HIV) antibody, hepatitis B surface antigen, and Rapid Plasma Reagin (RPR). 10. Agrees not to participate in another clinical trial with an investigational product for the duration of the study (12 months after the last dose of study vaccine or placebo i.e. 393 days).
Exclusion criteria
To be eligible to participate in this study, a subject must NOT meet any of the following criteria: 1. Living with or having daily contact with children age 5 years or less or a woman known to be pregnant. This includes significant contact at home, school, day-care, or equivalent facilities. 2. Nursing mother. 3. Living with or having daily contact with childcare workers. 4. Living with or having daily contact with elderly persons aged 70 years or more, or infirmed, diapered individuals, persons with disabilities or incontinent persons. This includes work or visits to nursing homes and day-care or equivalent facilities. 5. History of any gastroenteritis suggestive of Norovirus illness since screening serum antibody IgG P Particle ELISA testing was done. 6. History of any gastroenteritis within the past 2 weeks. 7. History of chronic functional dyspepsia, chronic gastroesophageal reflux disease, peptic ulcer disease, gastrointestinal hemorrhage, gall bladder disease, inflammatory bowel disease, irritable bowel syndrome, frequent diarrhea, chronic constipation, malabsorption, maldigestion, major Gastrointestinal (GI) surgery, or diverticulitis anytime during the subject's lifetime or any other chronic GI disorders that would interfere with interpretation of symptoms or evaluation during the study. 8. Routine use of medication other than oral contraceptive agents, anti-hypertensives, anti-depressants, vitamins and minerals. The use of any other medications should be discussed with the Sponsor and/or Central Safety Monitor (CSM). 9. History of any of the following medical illnesses: * Immunosuppression (disease or treatments that may affect immune system function) * Diabetes (including gestational diabetes during the pregnancy that required treatment other than dietary). * Cancer (malignancy other than a resolved or excised skin lesion). * Heart disease (hospitalization for a heart attack, arrhythmia, or syncope) * Unconsciousness (other than a single brief concussion) * Seizures (other than febrile seizures as a child \<5 years old) * Asthma requiring treatment with inhaler or medication in the past 2 years. * Neuro-inflammatory disease * Autoimmune disease * Eating disorder * Chronic headaches associated with vomiting * Chronic vomiting syndrome 10. Any current illness requiring daily medication other than vitamins, minerals, birth control, anti-hypertensives or anti-depressants. The use of any other medications should be discussed with the Sponsor and/or CSM. 11. Allergies or hypersensitivity to any component of the vaccine or challenge virus. 12. Any clinically significant abnormality detected on physical examination, including: * Murmur (other than a functional, ie normal, murmur) * Focal neurological abnormality * Hepatosplenomegaly * Lymphadenopathy * Jaundice 13. Hypertension defined as BP \> 150/90 mm Hg on two separate measurements. Chronic stable well-controlled hypertension on medications is allowed. 14. History of 3 or more hospitalizations for invasive bacterial infections (pneumonia, meningitis), acute or chronic dermatitis (e.g. eczema, seborrhea, psoriasis) or collagen vascular disease (e.g. Systemic Lupus Erythematosus (SLE) or dermatomyositis). 15. Presence of serious chronic illness. 16. Positive stool/fecal culture for bacterial pathogens (salmonella, campylobacter, E. coli 0157:H7, yersinia, or shigella) or positive stool/fecal screen for ova and parasites. 17. Employment in the food service industry, such as restaurants or cafeteria facilities. Specifically, this will include persons whose employment requires food processing in the 4 weeks following challenge. 18. Health-care workers with patient contact expected in the 4 weeks following challenge. 19. Expected contact (through employment or at home) with immunocompromised persons (HIV-positive, receiving immunosuppressive medications such as oral steroids or anti-neoplastic agents) in the 4 weeks following challenge. 20. Employment as an airline flight attendant scheduled to work in the 4 weeks following challenge. 21. Persons planning on taking a cruise in the 4 weeks following challenge. 22. Persons who plan to be living in a confined environment (e.g. ship, camp, or dormitory) within 4 weeks following challenge. 23. Persons who have consumed or plan to consume raw shellfish (e.g. oysters) from screening through post challenge Day 30. 24. Any of the following lab abnormalities (per the site local laboratory): * Absolute neutrophil count (ANC) outside the normal range * Total White Blood Cell Count (WBC) outside the normal range * Hemoglobin or hematocrit outside the normal range * Platelet count outside the normal range * Electrolytes \[Sodium (Na), Potassium (K), Chloride (Cl), Carbon dioxide (CO2)\], Blood Urea Nitrogen (BUN) and/or creatinine outside the normal range * Screening glucose \> upper limit of normal (ULN). Fasting glucose is not required * Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), alkaline phosphatase, bilirubin (total and indirect), or Gamma Glutamyl Transferase (GGT) outside the upper limit of the normal range * Screening urinalysis with a value higher than trace positive for urine protein or urine glucose, or urine Red Blood Cells (RBCs) (≥3; other than women during menses). All of the above labs may be repeated if outside the normal limits. If repeated and continue outside site normal ranges, may enroll if determined by the Principal Investigator (PI) to be not clinically significant and discussed with the Sponsor and/or CSM. 25. For women of child bearing potential, positive serum pregnancy test within 14 days or positive urine pregnancy test within one day of randomization. 26. Temperature \> 100.4°F orally, or symptoms of an acute self-limited illness such as an upper respiratory infection within 3 days of administering either dose of Norovirus Bivalent VLP vaccine or placebo control or the challenge product. 27. Resting heart rate \>100 beats per minute or \<55 beats per minute, respiratory rate ≥ 20 breaths per minute. If heart rate \<55 beat per minute and the investigator determines that this is not clinically significant and heart rate increases \> 55 beats per minute on moderate exercise, subject will not be excluded. Vital signs may be repeated. 28. Clinically abnormal screening electrocardiogram (ECG) defined as pathologic Q waves and significant ST-T wave changes; criteria for left ventricular hypertrophy; and any non-sinus rhythm excluding isolated premature atrial contractions. 29. Previous participation in a study of experimental norovirus infection or norovirus vaccine. 30. Study site personnel or their family members 31. Significant history of psychiatric hospitalization, alcohol abuse, or illicit drug use. 32. Receipt of a licensed live vaccine within 28 days or a licensed inactivated vaccine within 14 days of administration of either dose of vaccine or placebo or the challenge product. 33. Completion of an investigational vaccine or drug study within 7 days of randomization. 34. Receipt of systemic corticosteroids for greater than 7 days within the past six months. 35. Regular use of laxatives or anti-motility agents. 36. Receipt of blood or blood products within the past six months. 37. Subjects who are unwilling or unable to cease smoking from entry to the inpatient facility until discharge from the inpatient facility. 38. Other condition that in the clinical judgment of the investigator would jeopardize the safety or rights of a subject participating in the trial, would render the subject unable to comply with the protocol, or would interfere with the evaluation of the Vaccination stage or the evaluation of the Challenge stage. Challenge Stage
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percentage of Participants With Serious Adverse Events (SAEs) 365 Days Following the Last Study Vaccination | 365 Days Following Dose 2 (Up to 393 days) | A SAE was any experience that suggests a significant hazard, contraindication, side effect or precaution that: results in death, is life-threatening, required in-patient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect or is medically significant. |
| Percentage of Participants Experiencing Solicited Systemic Adverse Events Within 7 Days Post-Dose 2 | Within 7 days post-dose 2 | Systemic signs or symptoms included: elevated fever, headache, fatigue, muscle aches, chills, joint aches and gastrointestinal symptoms of nausea, vomiting, diarrhea, abdominal cramps/pain. |
| Percentage of Participants With Viral AGE Clinical Illness and Fecal Virus Excretion Detected by RT-PCR OR 4-Fold Rise In Anti-GII.4 Norovirus P Particle Antibody Titer | Symptoms collected from Challenge dose (at least 28 days after dose 2) to discharge (at least 96 hours after challenge dose) | Viral AGE due to Norovirus GII.4 strain during the inpatient stay that meets clinical illness definition 1,2 or 3 and positive for infection as measured by fecal virus excretion detected by Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) OR a 4-fold rise in Immunoglobulin G Enzyme-Linked Immunosorbent Assay (IgG ELISA) anti-GII.4 norovirus P particle antibody titer from pre-challenge (Within 2 weeks of Challenge Day 0) to post-challenge (Challenge Day 30). The clinical illness definitions are 1: diarrhea (defined as ≥ 3 loose or liquid stools OR \>400-600 grams of loose or liquid stools produced in any 24-hour period), 2: vomiting (defined as ≥ 2 vomiting episodes in any 24-hour period) or 3. One Vomiting episode plus any loose or liquid stool in any 24-hour period OR one vomiting episode plus at least 2 of the following 5 events: nausea, fever ≥99.7°F orally, abdominal cramps or pains, abdominal gurgling or bloating, or myalgia in any 24-hour period. |
| Percentage of Participants Experiencing Solicited Local Adverse Events Within 7 Days Post-Dose 1 | Within 7 days post-dose 1 | Local Adverse Events included local injection site reactions/symptoms: pain, tenderness, redness, and swelling. |
| Percentage of Participants Experiencing Solicited Local Adverse Events Within 7 Days Post-Dose 2 | Within 7 days post-dose 2 | Local Adverse Events included local injection site reactions/symptoms: pain, tenderness, redness, and swelling. |
| Percentage of Participants Experiencing Solicited Systemic Adverse Events Within 7 Days Post-Dose 1 | Within 7 days post-dose 1 | Systemic signs or symptoms included: elevated daily oral temperature (fever), headache, fatigue, muscle aches, chills, joint aches and gastrointestinal symptoms of nausea, vomiting, diarrhea, abdominal cramps/pain. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Percentage of Participants With GII.4 Seroresponse Rate (4-fold Rise) From Pre-challenge Day 0 to Post-Challenge Day 30 | Pre Challenge to 30 Days Post Challenge | Seroresponse was a 4-fold increase in IgG ELISA anti-GII.4 norovirus P particle antibody titer from pre-challenge to post-challenge. |
| Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline | Baseline to 28 days Post Dose 1 and 28 days Post Dose 2 | — |
| Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline | Baseline, 28 days Post Dose 1 and 28 days Post Dose 2 | — |
| Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | Baseline, 28 days Post Dose 1 and 28 days Post Dose 2 | — |
| Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMFR From Baseline | Baseline to 28 days post Dose 1 and 28 days post Dose 2 | — |
| Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | Baseline to 28 days post Dose 1 and 28 days post Dose 2 | Seroresponse was defined as a 4-Fold Rise from Baseline. |
| Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMT | Baseline, 28 days post Dose 1 and 28 days post Dose 2 | — |
| ELISA Immunoglobulin A (IgA)- Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline | Baseline to 28 days Post Dose 1 and 28 days Post Dose 2 | — |
| Percentage of Participants With ELISA IgA- Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline | Baseline to 28 days Post Dose 1 and 28 days Post Dose 2 | — |
| ELISA IgA- Anti-Norovirus GII.4 cVLP GMFR From Baseline | Baseline to 28 days post Dose 1 and 28 days post Dose 2 | — |
| Percentage of Participant With ELISA IgA- Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | Baseline to 28 days post Dose 1 and 28 days post Dose 2 | Seroresponse was defined as a 4-Fold Rise from Baseline. |
| Percentage of Participants With HBGA (PGM) - Anti-Norovirus GI.1 VLP Seroresponse From Baseline | Baseline to 28 days post Dose 1 and 28 days post Dose 2 | Seroresponse was defined as a 4-Fold Rise from Baseline |
| ELISA IgA- Anti-Norovirus GII.4 cVLP GMT | Baseline, 28 days post Dose 1 and 28 days post Dose 2 | — |
| HBGA (PGM) - Anti-Norovirus GI.1 VLP GMFR From Baseline | Baseline to 28 days post Dose 1 and 28 days post Dose 2 | HBGA (PGM) is Histoblood Group Antigen (Pig Gastric Mucin). |
| HBGA (PGM) - Anti-Norovirus GI.1 VLP GMT | Baseline, 28 days post Dose 1 and 28 days post Dose 2 | — |
| HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMFR From Baseline | Baseline to 28 days post Dose 1 and 28 days post Dose 2 | — |
| Percentage of Participants With HBGA (PGM) - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | Baseline to 28 days post Dose 1 and 28 days post Dose 2 | Seroresponse was defined as a 4-Fold Rise from Baseline. |
| HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMT | Baseline, 28 days post Dose 1 and 28 days post Dose 2 | — |
| Percentage of Participants With Unsolicited Non-Serious [i.e Other Than SAEs] Adverse Events (AEs) | Vaccination Stage: Initial vaccination until 28 days after second vaccination; or Challenge Stage: the day of challenge until 60 days after challenge | Unsolicited AEs indicates any and all AEs that occurred other than those that were solicited. |
| ELISA IgA- Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | Baseline, 28 days Post Dose 1 and 28 days Post Dose 2 | — |
| Percentage of Participants With 4-Fold Rise In Serum P-Particle Antibody Titer by ELISA or Detection of Norovirus GII.4 by RT-PCR in the Stool | Pre Challenge to 30 Days Post Challenge | — |
| Severity of Viral AGE Due to GII.4 Strain Assessed by Modified Vesikari Scoring System During the Inpatient Phase | Symptoms collected from Challenge dose (at least 28 days after dose 2) to discharge (at least 96 hours after challenge dose) | Vesikari Scoring System assesses the following symptoms: duration of diarrhea (days), maximum number of diarrheal stools/24 hours, duration of vomiting (days), maximum number of vomiting episodes/24 hours, fever and dehydration. Since the typical inpatient phase was four days in length, the duration of diarrhea scoring was modified to fit this time frame. Modified Vesikari Scale Total Score=0 to 17. Higher numbers are worse. |
| Severity of Viral AGE Due to GII.4 Strain Assessed by Post-Challenge Symptom Collection During the Inpatient Phase | Symptoms collected from Challenge dose (at least 28 days after dose 2) to discharge (at least 96 hours after challenge dose) | Score 1 was based on a subset of symptoms including: elevated oral temperature, myalgia, nausea, abdominal cramps, bloating, diarrhea, and vomiting. Score 2 was based on all Score 1 symptoms plus fatigue/malaise, chills, and loss of appetite. Total Score 1=0 to 20 and Total Score 2=0 to 29. Higher numbers are worse. |
| Duration of Viral AGE Due to GII.4 Strain During the Inpatient Phase | Symptoms collected from Challenge dose (at least 28 days after dose 2) to discharge (at least 96 hours after challenge dose) | Duration of symptoms was determined by a blinded committee review of each participant's symptoms. |
| Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Pre Challenge to 30 Days Post Challenge | — |
Other
| Measure | Time frame | Description |
|---|---|---|
| Correlation of GII.4 Serum HBGA Antibodies Prior to Challenge Associated With Protection From GII.4 Illness | Pre Challenge to Day 30 Post Challenge | Percentage of placebo subjects HBGA seropositive pre-challenge by illness status. |
| Correlation of GII.4 Serum HGBA Antibodies Prior to Challenge Associated With Protection From GII.4 Infection | Pre Challenge to Day 30 Post Challenge | Percentage of placebo subjects HBGA seropositive pre-challenge by infection status. |
Countries
United States
Participant flow
Recruitment details
Participants took part in the study at 5 investigative sites in the United States from 16 June 2012 to 18 March 2014.
Pre-assignment details
Healthy Volunteers were enrolled equally in 1 of 2 treatment groups, Norovirus Bivalent VLP Vaccine or Placebo.
Participants by arm
| Arm | Count |
|---|---|
| Norovirus Bivalent VLP Vaccine Norovirus Bivalent virus like particle (VLP) Vaccine (50 μg of GI.1 Norwalk VLP and 50 μg of GII.4 cVLP) adjuvanted with MPL and AI(OH)3, intramuscular (IM), Days 0 and 28. | 67 |
| Placebo Saline (0.9% NaCl and preservative-free), IM, Days 0 and 28. | 65 |
| Total | 132 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Lost to Follow-up | 2 | 1 |
| Overall Study | Non-compliance/Protocol deviation | 4 | 6 |
| Overall Study | Voluntary Withdrawal by Subject | 0 | 1 |
Baseline characteristics
| Characteristic | Norovirus Bivalent VLP Vaccine | Total | Placebo |
|---|---|---|---|
| Age, Continuous | 32.8 years STANDARD_DEVIATION 10.2 | 32.4 years STANDARD_DEVIATION 9.7 | 32.1 years STANDARD_DEVIATION 9.3 |
| Race/Ethnicity, Customized American Indian/Alaska Native | 1 participants | 1 participants | 0 participants |
| Race/Ethnicity, Customized Asian | 4 participants | 6 participants | 2 participants |
| Race/Ethnicity, Customized Black/African American | 37 participants | 73 participants | 36 participants |
| Race/Ethnicity, Customized Hispanic | 2 participants | 4 participants | 2 participants |
| Race/Ethnicity, Customized Multi-Racial | 0 participants | 1 participants | 1 participants |
| Race/Ethnicity, Customized Non-Hispanic | 65 participants | 128 participants | 63 participants |
| Race/Ethnicity, Customized White | 25 participants | 51 participants | 26 participants |
| Region of Enrollment United States | 67 participants | 132 participants | 65 participants |
| Sex: Female, Male Female | 32 Participants | 64 Participants | 32 Participants |
| Sex: Female, Male Male | 35 Participants | 68 Participants | 33 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 10 / 67 | 7 / 65 |
| serious Total, serious adverse events | 0 / 67 | 0 / 65 |
Outcome results
Primary
Percentage of Participants Experiencing Solicited Local Adverse Events Within 7 Days Post-Dose 1
Local Adverse Events included local injection site reactions/symptoms: pain, tenderness, redness, and swelling.
Time frame: Within 7 days post-dose 1
Population: MITT population included all participants who received at least one dose of study drug. Data is missing for 2 participants.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants Experiencing Solicited Local Adverse Events Within 7 Days Post-Dose 1 | 66.7 percentage of participants |
| Placebo | Percentage of Participants Experiencing Solicited Local Adverse Events Within 7 Days Post-Dose 1 | 28.1 percentage of participants |
Primary
Percentage of Participants Experiencing Solicited Local Adverse Events Within 7 Days Post-Dose 2
Local Adverse Events included local injection site reactions/symptoms: pain, tenderness, redness, and swelling.
Time frame: Within 7 days post-dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, who received a second dose.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants Experiencing Solicited Local Adverse Events Within 7 Days Post-Dose 2 | 54.0 percentage of participants |
| Placebo | Percentage of Participants Experiencing Solicited Local Adverse Events Within 7 Days Post-Dose 2 | 20.6 percentage of participants |
Primary
Percentage of Participants Experiencing Solicited Systemic Adverse Events Within 7 Days Post-Dose 1
Systemic signs or symptoms included: elevated daily oral temperature (fever), headache, fatigue, muscle aches, chills, joint aches and gastrointestinal symptoms of nausea, vomiting, diarrhea, abdominal cramps/pain.
Time frame: Within 7 days post-dose 1
Population: MITT included all participants who received at least one dose of study drug. Data is missing for 2 participants.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants Experiencing Solicited Systemic Adverse Events Within 7 Days Post-Dose 1 | 36.4 percentage of particpants |
| Placebo | Percentage of Participants Experiencing Solicited Systemic Adverse Events Within 7 Days Post-Dose 1 | 32.8 percentage of particpants |
Primary
Percentage of Participants Experiencing Solicited Systemic Adverse Events Within 7 Days Post-Dose 2
Systemic signs or symptoms included: elevated fever, headache, fatigue, muscle aches, chills, joint aches and gastrointestinal symptoms of nausea, vomiting, diarrhea, abdominal cramps/pain.
Time frame: Within 7 days post-dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, who received a second dose.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants Experiencing Solicited Systemic Adverse Events Within 7 Days Post-Dose 2 | 30.2 percentage of particpants |
| Placebo | Percentage of Participants Experiencing Solicited Systemic Adverse Events Within 7 Days Post-Dose 2 | 19.0 percentage of particpants |
Primary
Percentage of Participants With Serious Adverse Events (SAEs) 365 Days Following the Last Study Vaccination
A SAE was any experience that suggests a significant hazard, contraindication, side effect or precaution that: results in death, is life-threatening, required in-patient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect or is medically significant.
Time frame: 365 Days Following Dose 2 (Up to 393 days)
Population: MITT population included all participants who received at least one dose of study drug.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With Serious Adverse Events (SAEs) 365 Days Following the Last Study Vaccination | 0 percentage of participants |
| Placebo | Percentage of Participants With Serious Adverse Events (SAEs) 365 Days Following the Last Study Vaccination | 0 percentage of participants |
Primary
Percentage of Participants With Viral AGE Clinical Illness and Fecal Virus Excretion Detected by RT-PCR OR 4-Fold Rise In Anti-GII.4 Norovirus P Particle Antibody Titer
Viral AGE due to Norovirus GII.4 strain during the inpatient stay that meets clinical illness definition 1,2 or 3 and positive for infection as measured by fecal virus excretion detected by Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) OR a 4-fold rise in Immunoglobulin G Enzyme-Linked Immunosorbent Assay (IgG ELISA) anti-GII.4 norovirus P particle antibody titer from pre-challenge (Within 2 weeks of Challenge Day 0) to post-challenge (Challenge Day 30). The clinical illness definitions are 1: diarrhea (defined as ≥ 3 loose or liquid stools OR \>400-600 grams of loose or liquid stools produced in any 24-hour period), 2: vomiting (defined as ≥ 2 vomiting episodes in any 24-hour period) or 3. One Vomiting episode plus any loose or liquid stool in any 24-hour period OR one vomiting episode plus at least 2 of the following 5 events: nausea, fever ≥99.7°F orally, abdominal cramps or pains, abdominal gurgling or bloating, or myalgia in any 24-hour period.
Time frame: Symptoms collected from Challenge dose (at least 28 days after dose 2) to discharge (at least 96 hours after challenge dose)
Population: Modified intent-to-treat population (mITT) included all participants who received at least one dose of study drug, challenge stage.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With Viral AGE Clinical Illness and Fecal Virus Excretion Detected by RT-PCR OR 4-Fold Rise In Anti-GII.4 Norovirus P Particle Antibody Titer | 26.8 percentage of participants |
| Placebo | Percentage of Participants With Viral AGE Clinical Illness and Fecal Virus Excretion Detected by RT-PCR OR 4-Fold Rise In Anti-GII.4 Norovirus P Particle Antibody Titer | 32.1 percentage of participants |
p-value: 0.674Fisher Exact
Secondary
Duration of Viral AGE Due to GII.4 Strain During the Inpatient Phase
Duration of symptoms was determined by a blinded committee review of each participant's symptoms.
Time frame: Symptoms collected from Challenge dose (at least 28 days after dose 2) to discharge (at least 96 hours after challenge dose)
Population: Participants from the MITT population, all participants who received at least one dose of study drug, challenge stage with Viral AGE.
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Norovirus Bivalent VLP Vaccine | Duration of Viral AGE Due to GII.4 Strain During the Inpatient Phase | 32.1 hours |
| Placebo | Duration of Viral AGE Due to GII.4 Strain During the Inpatient Phase | 38.0 hours |
p-value: 0.199Wilcoxon (Mann-Whitney)
Secondary
ELISA IgA- Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT)
Time frame: Baseline, 28 days Post Dose 1 and 28 days Post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | ELISA IgA- Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | Baseline (Pre-Dose 1) | 4.1 titer |
| Norovirus Bivalent VLP Vaccine | ELISA IgA- Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | 28 days Post Dose 1 (n=63, 63) | 66.9 titer |
| Norovirus Bivalent VLP Vaccine | ELISA IgA- Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | 28 days Post Dose 2 (n=61, 58) | 47.5 titer |
| Placebo | ELISA IgA- Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | Baseline (Pre-Dose 1) | 4.0 titer |
| Placebo | ELISA IgA- Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | 28 days Post Dose 1 (n=63, 63) | 4.0 titer |
| Placebo | ELISA IgA- Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | 28 days Post Dose 2 (n=61, 58) | 4.0 titer |
Secondary
ELISA IgA- Anti-Norovirus GII.4 cVLP GMFR From Baseline
Time frame: Baseline to 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | ELISA IgA- Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 1 (n=63, 63) | 9.0 ratio |
| Norovirus Bivalent VLP Vaccine | ELISA IgA- Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 2 (n=61, 58) | 7.7 ratio |
| Placebo | ELISA IgA- Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 1 (n=63, 63) | 1.0 ratio |
| Placebo | ELISA IgA- Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 2 (n=61, 58) | 1.1 ratio |
Secondary
ELISA IgA- Anti-Norovirus GII.4 cVLP GMT
Time frame: Baseline, 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | ELISA IgA- Anti-Norovirus GII.4 cVLP GMT | Baseline (Pre-Dose 1) | 5.9 titer |
| Norovirus Bivalent VLP Vaccine | ELISA IgA- Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 1 (n=63, 63) | 54.1 titer |
| Norovirus Bivalent VLP Vaccine | ELISA IgA- Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 2 (n=61, 58) | 47.0 titer |
| Placebo | ELISA IgA- Anti-Norovirus GII.4 cVLP GMT | Baseline (Pre-Dose 1) | 5.8 titer |
| Placebo | ELISA IgA- Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 1 (n=63, 63) | 6.1 titer |
| Placebo | ELISA IgA- Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 2 (n=61, 58) | 6.2 titer |
Secondary
ELISA Immunoglobulin A (IgA)- Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline
Time frame: Baseline to 28 days Post Dose 1 and 28 days Post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | ELISA Immunoglobulin A (IgA)- Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline | 28 days Post Dose 1 (n=63, 63) | 16.3 ratio |
| Norovirus Bivalent VLP Vaccine | ELISA Immunoglobulin A (IgA)- Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline | 28 days Post Dose 2 (n= 61, 58) | 11.5 ratio |
| Placebo | ELISA Immunoglobulin A (IgA)- Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline | 28 days Post Dose 1 (n=63, 63) | 1.0 ratio |
| Placebo | ELISA Immunoglobulin A (IgA)- Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline | 28 days Post Dose 2 (n= 61, 58) | 1.0 ratio |
Secondary
HBGA (PGM) - Anti-Norovirus GI.1 VLP GMFR From Baseline
HBGA (PGM) is Histoblood Group Antigen (Pig Gastric Mucin).
Time frame: Baseline to 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | HBGA (PGM) - Anti-Norovirus GI.1 VLP GMFR From Baseline | 28 days Post Dose 1 (n=63, 63) | 25.6 ratio |
| Norovirus Bivalent VLP Vaccine | HBGA (PGM) - Anti-Norovirus GI.1 VLP GMFR From Baseline | 28 days Post Dose 2 (n=61, 58) | 31.8 ratio |
| Placebo | HBGA (PGM) - Anti-Norovirus GI.1 VLP GMFR From Baseline | 28 days Post Dose 1 (n=63, 63) | 1.0 ratio |
| Placebo | HBGA (PGM) - Anti-Norovirus GI.1 VLP GMFR From Baseline | 28 days Post Dose 2 (n=61, 58) | 1.0 ratio |
Secondary
HBGA (PGM) - Anti-Norovirus GI.1 VLP GMT
Time frame: Baseline, 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | HBGA (PGM) - Anti-Norovirus GI.1 VLP GMT | Baseline (Pre-Dose 1) | 17.5 titer |
| Norovirus Bivalent VLP Vaccine | HBGA (PGM) - Anti-Norovirus GI.1 VLP GMT | 28 days Post Dose 1 (n=63, 63) | 456.2 titer |
| Norovirus Bivalent VLP Vaccine | HBGA (PGM) - Anti-Norovirus GI.1 VLP GMT | 28 days Post Dose 2 (n=61, 58) | 573.5 titer |
| Placebo | HBGA (PGM) - Anti-Norovirus GI.1 VLP GMT | Baseline (Pre-Dose 1) | 15.2 titer |
| Placebo | HBGA (PGM) - Anti-Norovirus GI.1 VLP GMT | 28 days Post Dose 1 (n=63, 63) | 15.4 titer |
| Placebo | HBGA (PGM) - Anti-Norovirus GI.1 VLP GMT | 28 days Post Dose 2 (n=61, 58) | 15.1 titer |
Secondary
HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMFR From Baseline
Time frame: Baseline to 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 1 (n=63, 63) | 8.0 ratio |
| Norovirus Bivalent VLP Vaccine | HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 2 (n=61, 58) | 6.6 ratio |
| Placebo | HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 1 (n=63, 63) | 1.0 ratio |
| Placebo | HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 2 (n=61, 58) | 1.0 ratio |
Secondary
HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMT
Time frame: Baseline, 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMT | Baseline (Pre-Dose 1) | 119.2 titer |
| Norovirus Bivalent VLP Vaccine | HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 1 (n=63, 63) | 971.5 titer |
| Norovirus Bivalent VLP Vaccine | HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 2 (n=61, 58) | 803.0 titer |
| Placebo | HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMT | Baseline (Pre-Dose 1) | 127.5 titer |
| Placebo | HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 1 (n=63, 63) | 126.4 titer |
| Placebo | HBGA (PGM) - Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 2 (n=61, 58) | 136.7 titer |
Secondary
Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline
Time frame: Baseline to 28 days Post Dose 1 and 28 days Post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline | 28 days Post Dose 1 (n=63, 63) | 65.4 ratio |
| Norovirus Bivalent VLP Vaccine | Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline | 28 days Post Dose 2 (n= 61, 58) | 61.2 ratio |
| Placebo | Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline | 28 days Post Dose 1 (n=63, 63) | 1.0 ratio |
| Placebo | Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Fold Rise (GMFR) From Baseline | 28 days Post Dose 2 (n= 61, 58) | 0.9 ratio |
Secondary
Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT)
Time frame: Baseline, 28 days Post Dose 1 and 28 days Post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | Baseline (Pre-Dose 1) | 1857.6 titer |
| Norovirus Bivalent VLP Vaccine | Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | 28 days Post Dose 1 (n=63, 63) | 127209.7 titer |
| Norovirus Bivalent VLP Vaccine | Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | 28 days Post Dose 2 (n=61, 58) | 120552.8 titer |
| Placebo | Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | Baseline (Pre-Dose 1) | 1671.1 titer |
| Placebo | Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | 28 days Post Dose 1 (n=63, 63) | 1577.6 titer |
| Placebo | Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Geometric Mean Titer (GMT) | 28 days Post Dose 2 (n=61, 58) | 1606.3 titer |
Secondary
Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMFR From Baseline
Time frame: Baseline to 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 1 (n=63, 63) | 12.2 ratio |
| Norovirus Bivalent VLP Vaccine | Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 2 (n=61, 58) | 10.4 ratio |
| Placebo | Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 1 (n=63, 63) | 1.0 ratio |
| Placebo | Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMFR From Baseline | 28 days Post Dose 2 (n=61, 58) | 1.1 ratio |
Secondary
Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMT
Time frame: Baseline, 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMT | Baseline (Pre-Dose 1) | 5120.0 titer |
| Norovirus Bivalent VLP Vaccine | Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 1 (n=63, 63) | 63604.8 titer |
| Norovirus Bivalent VLP Vaccine | Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 2 (n=61, 58) | 56303.8 titer |
| Placebo | Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMT | Baseline (Pre-Dose 1) | 4958.8 titer |
| Placebo | Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 1 (n=63, 63) | 4845.9 titer |
| Placebo | Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP GMT | 28 days Post Dose 2 (n=61, 58) | 5306.9 titer |
Secondary
Percentage of Participants With 4-Fold Rise In Serum P-Particle Antibody Titer by ELISA or Detection of Norovirus GII.4 by RT-PCR in the Stool
Time frame: Pre Challenge to 30 Days Post Challenge
Population: MITT population included all participants who received at least one dose of study drug, Challenge stage.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With 4-Fold Rise In Serum P-Particle Antibody Titer by ELISA or Detection of Norovirus GII.4 by RT-PCR in the Stool | RT-PCR Alone | 53.6 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With 4-Fold Rise In Serum P-Particle Antibody Titer by ELISA or Detection of Norovirus GII.4 by RT-PCR in the Stool | 4-Fold rise in P-particle ELISA alone; n=56,51 | 7.1 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With 4-Fold Rise In Serum P-Particle Antibody Titer by ELISA or Detection of Norovirus GII.4 by RT-PCR in the Stool | Either RT-PCR or 4-fold rise in P-particle;n=56,52 | 53.6 percentage of participants |
| Placebo | Percentage of Participants With 4-Fold Rise In Serum P-Particle Antibody Titer by ELISA or Detection of Norovirus GII.4 by RT-PCR in the Stool | RT-PCR Alone | 60.4 percentage of participants |
| Placebo | Percentage of Participants With 4-Fold Rise In Serum P-Particle Antibody Titer by ELISA or Detection of Norovirus GII.4 by RT-PCR in the Stool | 4-Fold rise in P-particle ELISA alone; n=56,51 | 52.9 percentage of participants |
| Placebo | Percentage of Participants With 4-Fold Rise In Serum P-Particle Antibody Titer by ELISA or Detection of Norovirus GII.4 by RT-PCR in the Stool | Either RT-PCR or 4-fold rise in P-particle;n=56,52 | 61.5 percentage of participants |
Secondary
Percentage of Participants With ELISA IgA- Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline
Time frame: Baseline to 28 days Post Dose 1 and 28 days Post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With ELISA IgA- Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline | 28 days Post Dose 1 (n=63, 63) | 85.7 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With ELISA IgA- Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline | 28 days Post Dose 2 (n= 61, 58) | 80.3 percentage of participants |
| Placebo | Percentage of Participants With ELISA IgA- Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline | 28 days Post Dose 1 (n=63, 63) | 0.0 percentage of participants |
| Placebo | Percentage of Participants With ELISA IgA- Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline | 28 days Post Dose 2 (n= 61, 58) | 0.0 percentage of participants |
Secondary
Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase
Time frame: Pre Challenge to 30 Days Post Challenge
Population: Participants from the MITT population, all participants with at least one dose of study drug, challenge stage with data available for analysis.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Pre-Challenge | 0.0 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 1 (n=54,53) | 1.9 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 2 (n=52,52) | 38.5 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 3 (n=55,51) | 45.5 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 4 (n=52,47) | 44.2 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 10 (n=55,51) | 21.8 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 30 (n=56,52) | 0.0 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Any Day 1 to 30 | 53.6 percentage of participants |
| Placebo | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Any Day 1 to 30 | 60.4 percentage of participants |
| Placebo | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Pre-Challenge | 0.0 percentage of participants |
| Placebo | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 4 (n=52,47) | 55.3 percentage of participants |
| Placebo | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 1 (n=54,53) | 3.8 percentage of participants |
| Placebo | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 30 (n=56,52) | 0.0 percentage of participants |
| Placebo | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 2 (n=52,52) | 30.8 percentage of participants |
| Placebo | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 10 (n=55,51) | 33.3 percentage of participants |
| Placebo | Percentage of Participants With GII.4 Norovirus Positive RT-PCR in the Stool During the Inpatient and /or Outpatient Phase | Day 3 (n=55,51) | 51.0 percentage of participants |
Comparison: Any Day 1 to 30p-value: 0.562Fisher Exact
Secondary
Percentage of Participants With GII.4 Seroresponse Rate (4-fold Rise) From Pre-challenge Day 0 to Post-Challenge Day 30
Seroresponse was a 4-fold increase in IgG ELISA anti-GII.4 norovirus P particle antibody titer from pre-challenge to post-challenge.
Time frame: Pre Challenge to 30 Days Post Challenge
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With GII.4 Seroresponse Rate (4-fold Rise) From Pre-challenge Day 0 to Post-Challenge Day 30 | 7.1 percentage of participants |
| Placebo | Percentage of Participants With GII.4 Seroresponse Rate (4-fold Rise) From Pre-challenge Day 0 to Post-Challenge Day 30 | 52.9 percentage of participants |
Secondary
Percentage of Participants With HBGA (PGM) - Anti-Norovirus GI.1 VLP Seroresponse From Baseline
Seroresponse was defined as a 4-Fold Rise from Baseline
Time frame: Baseline to 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With HBGA (PGM) - Anti-Norovirus GI.1 VLP Seroresponse From Baseline | 28 days Post Dose 1 (n=63, 63) | 95.2 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With HBGA (PGM) - Anti-Norovirus GI.1 VLP Seroresponse From Baseline | 28 days Post Dose 2 (n=61, 58) | 100.0 percentage of participants |
| Placebo | Percentage of Participants With HBGA (PGM) - Anti-Norovirus GI.1 VLP Seroresponse From Baseline | 28 days Post Dose 1 (n=63, 63) | 0.0 percentage of participants |
| Placebo | Percentage of Participants With HBGA (PGM) - Anti-Norovirus GI.1 VLP Seroresponse From Baseline | 28 days Post Dose 2 (n=61, 58) | 0.0 percentage of participants |
Secondary
Percentage of Participants With HBGA (PGM) - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline
Seroresponse was defined as a 4-Fold Rise from Baseline.
Time frame: Baseline to 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With HBGA (PGM) - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 1 (n=63, 63) | 69.8 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With HBGA (PGM) - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 2 (n=61, 58) | 73.8 percentage of participants |
| Placebo | Percentage of Participants With HBGA (PGM) - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 1 (n=63, 63) | 0.0 percentage of participants |
| Placebo | Percentage of Participants With HBGA (PGM) - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 2 (n=61, 58) | 1.7 percentage of participants |
Secondary
Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline
Time frame: Baseline, 28 days Post Dose 1 and 28 days Post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline | 28 days Post Dose 1 (n=63, 63) | 100.0 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline | 28 days Post Dose 2 (n= 61, 58) | 100.0 percentage of participants |
| Placebo | Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline | 28 days Post Dose 1 (n=63, 63) | 1.6 percentage of participants |
| Placebo | Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GI.1 VLP Seroresponse (4-fold Rise) From Baseline | 28 days Post Dose 2 (n= 61, 58) | 3.4 percentage of participants |
Secondary
Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline
Seroresponse was defined as a 4-Fold Rise from Baseline.
Time frame: Baseline to 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 1 (n=63, 63) | 82.5 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 2 (n=61, 58) | 88.5 percentage of participants |
| Placebo | Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 1 (n=63, 63) | 1.6 percentage of participants |
| Placebo | Percentage of Participants With Pan-Ig ELISA - Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 2 (n=61, 58) | 1.7 percentage of participants |
Secondary
Percentage of Participants With Unsolicited Non-Serious [i.e Other Than SAEs] Adverse Events (AEs)
Unsolicited AEs indicates any and all AEs that occurred other than those that were solicited.
Time frame: Vaccination Stage: Initial vaccination until 28 days after second vaccination; or Challenge Stage: the day of challenge until 60 days after challenge
Population: MITT population included all participants who received at least one dose of study drug.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With Unsolicited Non-Serious [i.e Other Than SAEs] Adverse Events (AEs) | Post Dose 1 | 10.4 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With Unsolicited Non-Serious [i.e Other Than SAEs] Adverse Events (AEs) | Post Dose 2 (n=63, 64) | 14.3 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participants With Unsolicited Non-Serious [i.e Other Than SAEs] Adverse Events (AEs) | Challenge Stage | 39.3 percentage of participants |
| Placebo | Percentage of Participants With Unsolicited Non-Serious [i.e Other Than SAEs] Adverse Events (AEs) | Post Dose 1 | 23.1 percentage of participants |
| Placebo | Percentage of Participants With Unsolicited Non-Serious [i.e Other Than SAEs] Adverse Events (AEs) | Post Dose 2 (n=63, 64) | 18.8 percentage of participants |
| Placebo | Percentage of Participants With Unsolicited Non-Serious [i.e Other Than SAEs] Adverse Events (AEs) | Challenge Stage | 50.9 percentage of participants |
Secondary
Percentage of Participant With ELISA IgA- Anti-Norovirus GII.4 cVLP Seroresponse From Baseline
Seroresponse was defined as a 4-Fold Rise from Baseline.
Time frame: Baseline to 28 days post Dose 1 and 28 days post Dose 2
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Percentage of Participant With ELISA IgA- Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 1 (n=63, 63) | 73.0 percentage of participants |
| Norovirus Bivalent VLP Vaccine | Percentage of Participant With ELISA IgA- Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 2 (n=61, 58) | 72.1 percentage of participants |
| Placebo | Percentage of Participant With ELISA IgA- Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 1 (n=63, 63) | 3.2 percentage of participants |
| Placebo | Percentage of Participant With ELISA IgA- Anti-Norovirus GII.4 cVLP Seroresponse From Baseline | 28 days Post Dose 2 (n=61, 58) | 1.7 percentage of participants |
Secondary
Severity of Viral AGE Due to GII.4 Strain Assessed by Modified Vesikari Scoring System During the Inpatient Phase
Vesikari Scoring System assesses the following symptoms: duration of diarrhea (days), maximum number of diarrheal stools/24 hours, duration of vomiting (days), maximum number of vomiting episodes/24 hours, fever and dehydration. Since the typical inpatient phase was four days in length, the duration of diarrhea scoring was modified to fit this time frame. Modified Vesikari Scale Total Score=0 to 17. Higher numbers are worse.
Time frame: Symptoms collected from Challenge dose (at least 28 days after dose 2) to discharge (at least 96 hours after challenge dose)
Population: Participants from the MITT population, all participants who received at least one dose of study drug, challenge stage with Viral AGE.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Severity of Viral AGE Due to GII.4 Strain Assessed by Modified Vesikari Scoring System During the Inpatient Phase | 4.4 score on a scale | Standard Deviation 2 |
| Placebo | Severity of Viral AGE Due to GII.4 Strain Assessed by Modified Vesikari Scoring System During the Inpatient Phase | 7.1 score on a scale | Standard Deviation 2.1 |
p-value: 0.001Wilcoxon (Mann-Whitney)
Secondary
Severity of Viral AGE Due to GII.4 Strain Assessed by Post-Challenge Symptom Collection During the Inpatient Phase
Score 1 was based on a subset of symptoms including: elevated oral temperature, myalgia, nausea, abdominal cramps, bloating, diarrhea, and vomiting. Score 2 was based on all Score 1 symptoms plus fatigue/malaise, chills, and loss of appetite. Total Score 1=0 to 20 and Total Score 2=0 to 29. Higher numbers are worse.
Time frame: Symptoms collected from Challenge dose (at least 28 days after dose 2) to discharge (at least 96 hours after challenge dose)
Population: Participants from the MITT population, all participants who received at least one dose of study drug, challenge stage with Viral AGE.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Norovirus Bivalent VLP Vaccine | Severity of Viral AGE Due to GII.4 Strain Assessed by Post-Challenge Symptom Collection During the Inpatient Phase | Score 1 | 1.8 score on a scale | Standard Deviation 1 |
| Norovirus Bivalent VLP Vaccine | Severity of Viral AGE Due to GII.4 Strain Assessed by Post-Challenge Symptom Collection During the Inpatient Phase | Score 2 | 2.7 score on a scale | Standard Deviation 1.5 |
| Placebo | Severity of Viral AGE Due to GII.4 Strain Assessed by Post-Challenge Symptom Collection During the Inpatient Phase | Score 1 | 3.3 score on a scale | Standard Deviation 2 |
| Placebo | Severity of Viral AGE Due to GII.4 Strain Assessed by Post-Challenge Symptom Collection During the Inpatient Phase | Score 2 | 4.5 score on a scale | Standard Deviation 3 |
Comparison: Score 1p-value: 0.008Wilcoxon (Mann-Whitney)
Comparison: Score 2p-value: 0.037Wilcoxon (Mann-Whitney)
Other Pre-specified
Correlation of GII.4 Serum HBGA Antibodies Prior to Challenge Associated With Protection From GII.4 Illness
Percentage of placebo subjects HBGA seropositive pre-challenge by illness status.
Time frame: Pre Challenge to Day 30 Post Challenge
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Norovirus Bivalent VLP Vaccine | Correlation of GII.4 Serum HBGA Antibodies Prior to Challenge Associated With Protection From GII.4 Illness | 6.3 percentage of participants |
| Placebo | Correlation of GII.4 Serum HBGA Antibodies Prior to Challenge Associated With Protection From GII.4 Illness | 47.2 percentage of participants |
Other Pre-specified
Correlation of GII.4 Serum HGBA Antibodies Prior to Challenge Associated With Protection From GII.4 Infection
Percentage of placebo subjects HBGA seropositive pre-challenge by infection status.
Time frame: Pre Challenge to Day 30 Post Challenge
Population: Participants from the MITT population, all participants who received at least one dose of study drug, with data available for analysis.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Norovirus Bivalent VLP Vaccine | Correlation of GII.4 Serum HGBA Antibodies Prior to Challenge Associated With Protection From GII.4 Infection | 12.9 percentage of participants |
| Placebo | Correlation of GII.4 Serum HGBA Antibodies Prior to Challenge Associated With Protection From GII.4 Infection | 65.0 percentage of participants |