NCT02918006

A Phase 2 Influenza A Challenge Study Following Oral Administration of an H1N1 HA Ad-Vector Seasonal Flu Vaccine

Phase 2 Randomized, Controlled, Human Influenza A (H1N1) Challenge Study Following Administration of an Oral H1N1 HA Adenoviral-Vector Based Seasonal Influenza Vaccine and dsRNA Adjuvant to Healthy Adult Volunteers

• Status: Completed
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 179 (actual)
• Sponsor: Vaxart · Industry
• Sex: All
• Age: 18 Years – 49 Years
• Healthy volunteers: Accepted

Summary

A Phase 2 Randomized, Placebo- and Active-Controlled, Human Influenza A/California/04/2009 (H1N1) Challenge Study Following Administration of an Oral H1N1 Hemagglutinin (HA) Adenoviral-Vector Based Seasonal Influenza Vaccine and dsRNA Adjuvant (VXA-A1.1) to Healthy Adult Volunteers.

Detailed description

This is a Phase 2 randomized, placebo- and active-controlled, two-part study in which healthy adult volunteers with low or undetectable pre-existing antibodies against A/California/7/2009(H1N1) pdm09-like virus will be challenged with an influenza A/H1N1 human challenge strain approximately 90 days after vaccination with a single dose of H1N1 HA Adenoviral-vector based seasonal influenza vaccine and dsRNA adjuvant (VXA-A1.1), an injectable QIV vaccine, and/or placebo. An independent Safety Monitoring Committee (SMC) will oversee the safety of the study. To accommodate the limited size of the isolation unit that will be utilized for the challenge and post-challenge sequestration period, subjects will move through the study (enrollment, vaccination and challenge) sequentially in a total of 6 cohorts. Each cohort will randomize 30 subjects to obtain approximately 25 subjects per cohort for the challenge phase. Subjects will be randomized in a ratio of 2:2:1 (VXA-A1.1: Quadrivalent Influenza Vaccine (QIV): Placebo. The study will be conducted in two parts. Part A: Subjects will be randomized in a double-blinded manner to receive a single administration of one of three treatment arms: * Arm 1: VXA-A1.1 oral vaccine + placebo Intramuscular (IM) * Arm 2: QIV (IM) injection + oral placebo * Arm 3: Placebo IM injection + oral placebo Subjects will return to the site for \~8 visits and be contacted remotely at defined time points to be followed for immunogenicity and safety during study Part A. Part B: Subjects will be challenged with a wild-type influenza A H1 virus strain \~90 days following vaccination. Blood samples will be collected to evaluate immunogenicity. Subjects will remain in the isolation unit for 6 to 9 days post-challenge. Following challenge, influenza symptoms and signs will be assessed during the sequestration period. Blood samples and nasopharyngeal swab samples will be collected. Vital signs will be measured every 4 hours during waking hours. After release from the isolation unit subjects will return to the site 30 days post-challenge. Part B will continue for purposes of collecting long term safety follow-up (serious adverse events (SAEs), AEs of special interest (AESIs) and any new onset of chronic illness (NOCI) via phone contacts through 1 year post-vaccination (Day 365).

Conditions

• Influenza

Interventions

Type	Name	Description
BIOLOGICAL	VXA-A1.1	Enteric coated oral vaccine tablet
BIOLOGICAL	Fluzone®	Fluzone Quadravalent (Fluzone®) influenza vaccine (QIV) suspension for intramuscular (IM) injection
OTHER	Placebo Tablets	Placebo tablets similar in size, color and number to the active oral tablet vaccine drug product
OTHER	Saline Solution for Placebo IM Injection

Timeline

• Start date: 2016-08-31
• Primary completion: 2017-08-08
• Completion: 2018-01-19
• First posted: 2016-09-28
• Last updated: 2022-10-06
• Results posted: 2022-10-06

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study