Dose, Safety, Tolerability and Immunogenicity of an Influenza H1 Stabilized Stem Ferritin Vaccine in Healthy Adults

Background:

The flu is a common viral infection that can be deadly for certain people. Vaccines against flu have been developed to teach the body to prevent or fight the infection. A new vaccine may help the body to make an immune response to H1 flu, a flu strain that infects humans.

Objective:

To test the safety and effectiveness of the H1 Stabilized Stem Ferritin vaccine (VRC-FLUNPF099-00-VP).

Eligibility:

Healthy people ages 18-70 years old who got at least 1 licensed flu vaccine since January 1, 2014.

Design:

Participants received 1 or 2 vaccinations by injections (shots) in the upper arm muscle over 4 months. Participants received a thermometer and recorded their temperature and symptoms every day a diary card for 7 days after each injection. The injection site was checked for redness, swelling, or bruising.

Participants had 9-11 follow-up visits over 12-15 months. At follow-up visits, participants had blood drawn and were checked for health changes or problems. Participants who reported influenza-like illness had nose and throat swabs for evaluation of viral infection.

Some participants had apheresis. A needle was placed into a vein in both arms. Blood was removed through a needle in the vein of one arm. A machine removed the white blood cells and then the rest of the blood was returned to the participant through a needle in the other arm.

A separate consent was provided to participants for genetic testing on their samples.

Study Design: This was a Phase I, open-label, dose escalation study to evaluate the dose, safety, tolerability, and immunogenicity of VRC-FLUNPF099-00-VP in two regimens. The hypotheses were that the vaccine is safe and tolerable and will elicit an immune response. The primary objective was to evaluate the safety and tolerability of the investigational vaccine in healthy adults. Secondary objectives were related to immunogenicity of the investigational vaccine and dosing regimen.

Study Products: The investigational vaccine, VRC-FLUNPF099-00-VP (H1ssF_3928), was developed by the Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases (NIAID) and is composed of Helicobacter pylori non-heme ferritin assembled with influenza virus H1 haemagglutinin (HA) insert to form a nanoparticle displaying eight HA stabilized stem trimers from A/New Caledonia/20/1999 (H1N1) influenza. The vaccine was supplied in single-use vials at a concentration of 180 mcg/mL. H1ssF_3928 was administered intramuscularly (IM) in the deltoid muscle via needle and syringe.

Participants: Healthy adults between the ages of 18-70 years, inclusive.

Study Plan: The study evaluated the safety, tolerability and immunogenicity of 1 or 2 doses of the H1ssF_3928 vaccine in a dose-escalation design. In Group 1, five participants received a single low dose (20 mcg) of H1ssF_3928 on Day 0. For Group 1, the protocol required 1 vaccination visit, about 9 follow-up visits, and a telephone contact after vaccination.

Once the low dose was assessed as safe and well tolerated, enrollment began for Group 2A. Groups 2A, 2B, 2C, and 2D were stratified by age as shown in the vaccination schema below. In Group 2A, participants received a higher dose (60 mcg) of H1ssF_3928 on Day 0. Once this higher dose was assessed as safe and well tolerated, participants in Group 2A received a second vaccination at Week 16 and enrollment began for Groups 2B, 2C, and 2D. For Groups 2A, 2B, 2C, and 2D, the protocol required 2 vaccination visits, about 11 follow-up visits, and a telephone contact after each vaccination. Group 2A completed the product administration schedule per protocol. While most participants in Groups 2B-2D completed the second dose administration per protocol, one participant was not able to receive the second dose due to moving out of the area and 11 participants were not able to receive their second dose due to the COVID-19 pandemic.

For all groups, solicited reactogenicity was evaluated using a 7-day diary card. Assessment of vaccine safety included clinical observation and monitoring of hematological and chemical parameters at clinical visits throughout the study.

VRC 321 Vaccination Schema:

Group: 1; Age Cohort: 18-40; Participants: 5; Day 0: 20 mcg

Group: 2A; Age Cohort: 18-40; Participants: 12; Day 0: 60 mcg; Week 16: 60 mcg

Group: 2B; Age Cohort: 41-49; Participants: 12; Day 0: 60 mcg; Week 16: 60 mcg

Group: 2C; Age Cohort: 50-59; Participants: 12; Day 0: 60 mcg; Week 16: 60 mcg

Group: 2D; Age Cohort: 60-70; Participants: 11\*; Day 0: 60 mcg; Week 16: 60 mcg

Total: 52\*

\*Recruitment for the final open group, Group 2D, was ongoing to meet the accrual target of 53 participants. However, due to the COVID-19 pandemic, enrollment was discontinued with a total of 52 participants enrolled.

Study Duration:

Group 1: Participants were evaluated for 52 weeks following the vaccine administration and through an influenza season.

Groups 2A, 2B, 2C, 2D: Participants were evaluated for 52 weeks following the last vaccine administration and through an influenza season.

Eligibility Criteria:
INCLUSION CRITERIA:

1. Healthy adults between the ages of 18-70 years inclusive
2. Based on history and examination, in good general health and without history of any of the conditions listed in the exclusion criteria
3. Received at least one licensed influenza vaccine from 2014 to the present
4. Able and willing to complete the informed consent process
5. If enrolled in Group 1: Available for clinic visits for 52 weeks after enrollment and through an influenza season
6. If enrolled in Group 2A, 2B, 2C, or 2D: Available for clinic visits for 68 weeks after enrollment and through an influenza season
7. Willing to have blood samples collected, stored indefinitely, and used for research purposes
8. Able to provide proof of identity to the satisfaction of the study clinician completing the enrollment process
9. Physical examination and laboratory results without clinically significant findings and a Body Mass Index (BMI) less than or equal to 40 within the 28 days before enrollment

   Laboratory Criteria within 28 days before enrollment
10. White blood cells (WBC) and differential either within institutional normal range or accompanied by the site Principal Investigator (PI) or designee approval
11. Total lymphocyte count greater than or equal to 800 cells/mm\^3
12. Platelets = 125,000 - 500,000/mm3
13. Hemoglobin within institutional normal range
14. Serum iron either within institutional normal range or accompanied by the site PI or designee approval
15. Serum ferritin within institutional normal range or accompanied by the site PI or designee approval
16. Alanine aminotransferase (ALT) less than or equal to 1.25 x institutional upper limit of normal (ULN)
17. Aspartate aminotransferase (AST) less than or equal to 1.25 x institutional ULN
18. Alkaline phosphatase (ALP) \<1.1 x institutional ULN
19. Total bilirubin within institutional normal range
20. Serum creatinine less than or equal to 1.1 x institutional ULN
21. Negative for HIV infection by an FDA-approved method of detection

    Criteria applicable to women of childbearing potential:
22. Negative beta-human chorionic gonadotropin (beta-HCG) pregnancy test (urine or serum) on the day of enrollment
23. Agreed to use an effective means of birth control from at least 21 days prior to enrollment through the end of the study

EXCLUSION CRITERIA:

1. Breast-feeding or planning to become pregnant during the study.

   Participant has received any of the following substances:
2. More than 10 days of systemic immunosuppressive medications or cytotoxic medications within the 4 weeks prior to enrollment or any within the 14 days prior to enrollment
3. Blood products within 16 weeks prior to enrollment
4. Live attenuated vaccines within 4 weeks prior to enrollment
5. Inactivated vaccines within 2 weeks prior to enrollment
6. Investigational research agents within 4 weeks prior to enrollment or planned to receive investigational products while on the study
7. Current allergy treatment with allergen immunotherapy with antigen injections, unless on maintenance schedule
8. Current anti-TB (tuberculosis) prophylaxis or therapy
9. Previous investigational H1 influenza vaccine
10. Previous investigational ferritin-based vaccine
11. Receipt of a licensed influenza vaccine within 6 weeks before trial enrollment

    Participant has a history of any of the following clinically significant conditions:
12. Serious reactions to vaccines that preclude receipt of study vaccinations as determined by the investigator
13. Hereditary angioedema, acquired angioedema, or idiopathic forms of angioedema
14. Asthma that is not well controlled
15. Diabetes mellitus (type I or II), with the exception of gestational diabetes
16. Thyroid disease that is not well controlled
17. Idiopathic urticaria within the past year
18. Autoimmune disease or immunodeficiency
19. Hypertension that is not well controlled (baseline systolic \> 140 mmHg or diastolic \> 90 mmHg)
20. Bleeding disorder diagnosed by a doctor (e.g. factor deficiency, coagulopathy, or platelet disorder requiring special precautions) or significant bruising or bleeding difficulties with IM injections or blood draws
21. Malignancy that is active or history of malignancy that is likely to recur during the period of the study.
22. Seizure disorder other than 1) febrile seizures, 2) seizures secondary to alcohol withdrawal more than 3 years ago, or 3) seizures that have not required treatment within the last 3 years
23. Asplenia, functional asplenia or any condition resulting in the absence or removal of the spleen
24. Guillain-Barré Syndrome
25. Any medical, psychiatric, social condition, occupational reason or other responsibility that, in the judgment of the investigator, is a contraindication to protocol participation or impairs a participant's ability to give informed consent.