Clinical trial NCT03992872: Phase 2 Open-label Study of Alum-adjuvanted Chikungunya Virus-like Particle Vaccine (PXVX0317)
Official title: A Phase 2 Open-label Study to Assess the Safety and Immunogenicity of an Alum-adjuvanted Chikungunya Virus-like Particle Vaccine (PXVX0317) in Prior Recipients of Other Alphavirus Vaccines Versus Alphavirus Naïve Controls.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE2
Conditions: Chikungunya
Lead sponsor: Bavarian Nordic
Sponsor class: INDUSTRY
Collaborators: name: Walter Reed Army Institute of Research (WRAIR)
name: Emergent BioSolutions
First posted: 2019-06-20
Enrollment: 60
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Open Label Safety and Immunogenicity
Primary purpose: PREVENTION

Brief summary: This was a phase 2 parallel-group age- and gender-matched open label study in healthy adults 18-65 years of age to assess the safety and immunogenicity of an alum-adjuvanted chikungunya virus-like particle vaccine (PXVX0317; CHIKV VLP vaccine) in prior recipients of other alphavirus vaccines versus alphavirus naïve controls.

Detailed description: It is currently unknown whether prior exposure to heterologous alphaviruses will enhance or interfere with immune responses to chikungunya virus (CHIKV) exposure or vaccination. The objective of this study was to evaluate the safety and immunogenicity of the chikungunya vaccine candidate PXVX0317 when administered to prior recipients of experimental alphavirus vaccines versus alphavirus naïve gender- and age-matched controls.

Eligibility criteria: Inclusion Criteria:

* Age 18 to 65 years old (inclusive)
* For women of childbearing potential, a negative pregnancy test at screening and on vaccination day, practicing highly effective contraception for at least 30 days prior to vaccination, and willing to use a highly effective method of contraception through study completion.
* Able and willing to provide informed consent for study participation prior to screening procedures.
* Free of obvious health problems as established by medical history and clinical examination at screening and enrollment.
* Available to participate for the duration of the study (approximately 8 months).
* For the cohort of prior alphavirus vaccine recipients, a documented history of prior alphavirus vaccination.

Exclusion Criteria:

* Acute disease or febrile illness at the time of screening or enrollment.
* Clinically significant cardiac, respiratory, rheumatologic or other medical or psychiatric condition that, in the opinion of the Investigator, places the subject at increased risk or affects their ability to understand and comply with study procedures.
* Abnormal screening lab test result that, in the opinion of the investigator, obscures interpretation of the safety data or suggests a clinically significant cardiac, respiratory, rheumatologic or other medical condition that places the subject at increased risk.
* Pregnant, lactating or planning to become pregnant during the study period.
* Laboratory evidence of infection with Hepatitis B, C or HIV.
* History of naturally (non-laboratory) acquired chikungunya or other alphavirus infection or travel to a WHO-designated chikungunya-endemic region within 30 days prior to Day 1.
* History of acute allergic reaction to any component of CHIKV VLP vaccine or Alhydrogel®.
* Current (30 days prior to Day 1) or anticipated use of systemic immunomodulatory or immunosuppressive medications.
* History of splenectomy, immunosuppressive condition, autoimmune disease, or immunodeficient condition.
* Family history of congenital or hereditary immunodeficiency.
* Suspected or known current alcohol abuse that, in the opinion of the Investigator, would interfere with the subject's ability to understand and comply with study procedures.
* Current intravenous drug use.
* Prior receipt of an investigational chikungunya vaccine.
* Receipt or planned receipt of any licensed vaccine from 30 days prior to Day 1 through Day 29 study visit.
* Participation in another clinical trial during the study period in which an investigational product is administered.
* For the alphavirus naïve group, history of prior alphavirus vaccination is exclusionary.

Primary outcomes:
measure: Percentage of Participants With 4-fold Rise in Anti-CHIKV Neutralizing Antibody Response
timeFrame: Day 22 (21 days after vaccination)
Secondary outcomes:
measure: Geometric Mean Titer of Anti-CHIKV Neutralizing Antibody Response
timeFrame: Day 1, 8, 22, 29, 57, 182
measure: Percentage of Participants With 4-fold Rise in Anti-CHIKV Neutralizing Antibody Response
timeFrame: Day 8, 29, 57, 182
measure: Percentage of Participants With Anti-CHIKV Neutralizing Antibody at or Above Selected Thresholds
timeFrame: Day 1, 8, 22, 29, 57, 182
measure: Geometric Mean Titer of Anti-CHIKV Total Antibody Response
timeFrame: Day 1, 22, 29
measure: Percentage of Participants With 4-fold Rise in Anti-CHIKV Total Antibody Response
timeFrame: Day 22, 29
measure: Geometric Mean Titer of Anti-VEEV Neutralizing Antibody Response
timeFrame: Day 1, 22, 29
measure: Number of Participants With Anti-CHIKV Total Antibody Titers of at Least 40,160 or 640
timeFrame: Days 1, 22, and 29
measure: Percentage of Participants With 4-fold Rise in Anti-VEEV Neutralizing Antibody Response
timeFrame: Day 22 and 29
measure: Percentage of Participants With Anti-VEEV PRNT Neutralizing Activity at or Above Selected Thresholds
timeFrame: Day 1, 22, 29
measure: Geometric Mean Titer of Anti-VEEV Total Antibody Response
timeFrame: Day 1, 22, 29
measure: Percentage of Participants With 4-fold Rise in Total ELISA IgG Antibody Against VEEV
timeFrame: Day 22, 29
measure: Number of Participants With Anti-VEEV Total Antibody Titers of at Least 40,160 or 640
timeFrame: Days 1, 22, and 29
Other outcomes:
Locations:
city: Fort Deterick
country: United States
facility: United States Army Medical Research Institute of Infectious Diseases
state: Maryland
city: Silver Spring
country: United States
facility: Walter Reed Army Institute of Research
state: Maryland
Study officials:
affiliation: Emergent BioSolutions
name: James McCarty, MD
role: STUDY_DIRECTOR
References: