Plague
Conditions
Keywords
Yersinia pestis, vaccine, plague, Flagellin/F1/V, Parent Protocol of 15-0104
Brief summary
Plague is an infectious disease of animals and humans caused by bacteria, Yersinia pestis. Modern antibiotics are effective against plague, but if an infected person is not treated promptly the disease is likely to cause illness or death. The purpose of this study is to evaluate at the safety, immunogenicity (bodily defense reaction), and tolerability of a new research vaccine. Up to 48 people will be enrolled in this study at the Center for Vaccine Development at Saint Louis University. Four groups of 12 volunteers will be given vaccine or placebo (inactive substance) one group at a time starting with the lowest dose working up to the highest dose. Shots will be given in the arm 2 times separated by 28 days. Study procedures include: physical exam, blood samples, and recording temperature and side effects in a memory aid. Participants will be involved in study related procedures for about 13 months.
Detailed description
Yersinia (Y.) pestis, a gram-negative coccobacillus, causes an acute and often fatal disease that may appear in 1 of several major manifestations: bubonic, septicemic, and pneumonic. Transmission to humans most commonly occurs via a bite by infectious fleas and is associated with regional lymphadenopathy or bubo. Pneumonic plague would be the most likely outcome in the case of a bio-terrorism attack. Currently, there is no effective licensed vaccine that protects against pneumonic plague. The investigational product, flagellin/F1/V in phosphate-buffered saline, pH 6.2, is a vaccine that is designed to provide protection against respiratory exposure to Y. pestis, i.e., pneumonic plague. The general hypothesis to be tested is that the flagellin/F1/V vaccine will induce a robust humoral immune response against the F1 and V antigens of Y. pestis without serious adverse events (SAEs) when the vaccine is given intramuscularly (IM) on 2 occasions separated by about 28 days at doses of 1, 3, 6 and 10 micrograms (mcg). Since the major rationale for this vaccine is protection against respiratory exposure to Y. pestis following a bio-terrorism attack, the initial study population will be 18-45 year old healthy volunteers. The primary objective of this study is to assess the safety and immunogenicity of escalating dosages of Flagellin/F1/V vaccine among healthy subjects given 2 doses of vaccine by the IM route on Days 0 and 28. The secondary objective of this study is to evaluate the reactogenicity and cell mediated immune responses of escalating dosages of Flagellin/F1/V vaccine among healthy subjects when given 2 doses of vaccine by the IM route on Days 0 and 28. Participants will include up to 48 healthy male and female volunteers. This study is designed as a randomized, placebo controlled, double-blind (within dosing group), dose escalation Phase I study. The study will consist of 4 groups to be dosed sequentially. Each group will consist of 10 individuals that receive vaccine and 2 that receive placebo. Each subject will receive an IM vaccination on Days 0 and 28. The initial dose to be evaluated will be 1 mcg/dose. Following assessment of safety and reactogenicity data of each group by the Safety Monitoring Committee the vaccine doses will be increased sequentially from 1, to 3, to 6, to 10 mcg/dose. Following vaccination, subjects will return to the clinical site on Days 1, 14, and 28 following the initial vaccination and on Days 1, 14, 28, 40, and 180 following the second vaccination. In addition, subjects will be contacted by phone on Day 3 after each vaccination to review the memory aid, query for adverse event (AEs)/SAEs and concomitant medications. All subjects will complete a subject memory aid for 15 days following each vaccination (Day 0-14). Unsolicited, non-serious AEs will be collected through Day 56 (Visit 8, 26-30 days following the final vaccination). SAEs will be collected throughout the study period Day 393 (Visit 11, 365 days + 14 days after the second vaccination). Blood samples for safety labs will be collected at screening, day of initial vaccination and at 14 days after each vaccination. Specimens will be collected for immunologic assays at the noted clinic visits, as well as at 6 months post the final vaccination.
Interventions
Flagellin/F1/V recombinant fusion protein vaccine administered by the intramuscular route on Days 0 and 28 at a dose of 1, 3, 6, or 10 micrograms (mcg). It is a clear, colorless solution.
Phosphate buffered saline (PBS) used as diluent and placebo.
Sponsors
Study design
Eligibility
Inclusion criteria
Inclusion criteria that must met prior to the initial vaccination: * At least 18 and less than or equal to 45 years of age at the time of first vaccination. * Never had plague or disease caused by Yersinia pestis. * Able to provide informed consent. * Read, signed, and dated informed consent document. * Available for follow-up for the planned duration of the study. * Satisfactory medical assessment with no clinically significant and relevant abnormalities as established by medical history and physical examination at screening. * If the subject is female and of childbearing potential, negative serum pregnancy test at screening and negative urine or serum pregnancy test within 24 hours prior to each vaccination. * If the subject is female and of childbearing potential, she agrees to use acceptable contraception and remain on the same method during the study as they were using prior to entering the study, and not become pregnant for 28 days following the last vaccination. A woman is considered of childbearing potential unless post-menopausal or surgically sterilized. Acceptable contraception methods are restricted to effective devices \[e.g., intrauterine device (IUD), NuvaRing®\] or licensed hormonal products with use of method for a minimum of 30 days prior to vaccination, a monogamous relationship with a vasectomized partner and abstinence from sexual intercourse with men. * Negative enzyme-linked immunosorbent assay (ELISA) for human immunodeficiency virus (HIV). * Negative hepatitis B surface antigen and negative antibody to hepatitis C virus. * Safety labs have to be within institutional normal limits, or as otherwise specified. * Weight: greater than or equal to 110 pounds. * Body Mass Index (BMI) of greater than or equal to 19 and less than 33. * Subject agrees not to donate blood for the duration of their study participation. Inclusion criteria that must be met prior to the second vaccination: * Never had plague or disease caused by Yersinia pestis. * Satisfactory medical assessment with no clinically significant and relevant abnormalities as established by medical history. * If the subject is female and of childbearing potential, negative urine or serum pregnancy test within 24 hours prior to vaccination. * If the subject is female and of childbearing potential, she has remained on the same contraception method as used prior to entering the study, and not become pregnant for 28 days following the last vaccination. A woman is considered of childbearing potential unless post-menopausal or surgically sterilized. Acceptable contraception methods are restricted to effective devices (e.g., IUDs, NuvaRing®) or licensed hormonal products with use of method for a minimum of 30 days prior to vaccination, a monogamous relationship with a vasectomized partner and abstinence from sexual intercourse with men. * Post dose one safety labs (Day 14) have to be within institutional normal limits, or as otherwise specified at the Day 14 post the initial vaccination or any observed laboratory toxicities have to be resolved prior to the second vaccination.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Incidence of Grade 3 or above laboratory toxicities associated with vaccination for each dose group. | Through Day 42 (14 days after the second vaccination). |
| Incidence of serious adverse events (SAEs)associated with vaccination for each dose group. | Throughout the duration of the study (Visit 11, 365 + 14 days after the second vaccination or through termination visit, if terminated early). |
| Peak antibody titer [immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) for F1 and V antigen] for each dose group as determined by analysis of serum samples. | Days: 0, 14, 28, 42, 56, 68 and 208. |
Secondary
| Measure | Time frame |
|---|---|
| Occurrence of localized reactogenicity symptoms for each dose group. | Within 15 days (Day 0-14) of each vaccination. |
| Distribution of the cytokine expression levels in peripheral blood mononuclear cells (PBMCs) following ex vivo stimulation for each dose group. | Day 0, 14, 42, 56, and 68. |
| Assessment of cytokine responses (TNF-alpha, IL-6 and IL-1 beta) as measured in serum samples. | Serum samples obtained on the day of vaccination, and on Visit 3 and 6 (1 day after each vaccination) and Visit 4 and 7 (14 days after each vaccination). |
| Occurrence of unsolicited adverse events (AEs) for each dose group. | Within 28 days of each vaccination. |
| Occurrence of systemic reactogenicity symptoms for each dose group. | Within 15 days (Day 0-14) of each vaccination. |
Countries
United States