Typhoid Fever
Conditions
Brief summary
This was a randomized, double-blind, ascending dose study conducted at a single clinical research center.
Detailed description
Healthy adult subjects aged 18 to 55 years were assigned to 3 ascending dose cohorts of Typhax (0.5, 2.5 or 10 mcg Vi antigen). Groups of 15 subjects in each dose cohort were randomized to receive Typhax, Typhim Vi (25 mcg Vi antigen) or placebo (saline) in a ratio of 3:1:1, respectively. Typhax and placebo (saline) was administered as two dose regimen (Days 0 and 28), and Typhim Vi was given as a single dose (Day 0) with matching placebo on Day 28. All doses were administered by a unblinded third-party as 0.5 mL by intramuscular (IM) injection. Safety and reactogenicity endpoints was assessed at 14 and 28 days after the first Typhax vaccination and 14 days after the second vaccination. Immunogenicity was assessed using an enzyme-linked immunosorbent assay (ELISA) to measure anti-Vi antibody serum titers on days 0, 14, 28, 42 and 180. A positive immune response (seroconversion) by ELISA is defined as at least a 4-fold increase over baseline in the Vi-specific ELISA.
Interventions
BIOLOGICALTyphax (investigational typhoid fever candidate vaccine)
BIOLOGICALPlacebo
Placebo is administered to the control group on Day 0 and 28
BIOLOGICALActive Comparator Typhim Vi
A single dose of commercial typhoid fever vaccine Typhim Vi is administered on Day 0, followed by placebo control on Day 28
Sponsors
Matrivax Research and Development Corporation
Study design
Allocation
RANDOMIZED
Intervention model
SEQUENTIAL
Primary purpose
PREVENTION
Masking
DOUBLE (Subject, Investigator)
Masking description
Study vaccine will be administered by an unblinded staff member at the clinic
Intervention model description
Randomized, Ascending Dose
Eligibility
Sex/Gender
ALL
Age
18 Years to 55 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy adult men or women who are not pregnant or planning to become pregnant during study duration aged 18 to 55 years. * Clinical laboratory parameters within normal laboratory limits or not found to be clinically significant by the PI
Exclusion criteria
* Relevant history of physical or psychiatric illness or medical disorder that required treatment. * Known or suspected hypersensitivity to investigational product * Immunocompromised subjects * Previous Typhoid vaccination or elevated anti-Vi antibodies at screening * Known history of Typhoid infection in the previous 6 months * Positive HIV, HBsAg, or HCV screen * Any other condition or abnormality that, in the opinion of the Investigator, may compromise the safety of the patients
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of participants reporting solicited injection site and systemic events and unsolicited adverse events following vaccination with Typhax | Days 0 up to Day 56 (= 28 Days post second vaccination) | Solicited Injection Site reactions: Pain, Tenderness, Erythema, Induration; Solicited Systemic Reactions Fever, Headache, Joint Pain, Joint Swelling, Fatigue, Myalgia, Nausea, Vomiting, Diarrhea |
| Number of participants reporting adverse events following vaccination with Typhax | Days 0 up to Day 210 | Adverse events are assessed at study visits by PI for seriousness, relationship to investigational product , severity and other possible etiologies |
| Anti-Vi IgG antibody seroconversion and geometric mean antibody titers | Day 0 - Day 14 | The immunogenicity will be measured by ELISA for anti-Vi percent seroconversion and GMTs before and at day 14 after vaccination. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Vi-specific B-cell ELISPOT responses | Days 0 through 38 | Immunogenicity was evaluated by comparing the number of Vi-specific B-cells by ELISPOT in PBMC samples |
Outcome results
None listed