NCT03877926Phase 3Completed

VELOCITY: An Anthrax Vaccine Clinical Study

Compare the available registry edits below. Primary completion is the date data collection ends for the main study measures; it does not tell you when results will be published.

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Primary completion2020-08-06Actual

Enrollment · participants3689Actual

Source updated2026-05-06Last update listed in the registry record

Version history

Changes to this trial

Last 12 months

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Posted 2026-05-06 · 1 field changed

Enrollment · participant count

Recorded edit

− Previous value

count: 3862; type: ACTUAL

+ Updated value

count: 3689; type: ACTUAL

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Study details

Conditions studied

Anthrax

Treatments or interventions studied

AV7909Biological
BioThraxBiological

Primary outcomes · main study measures

Read the study measures

measure: Geometric Mean Titer (GMT) of Toxin Neutralizing Antibody (TNA) 50% Neutralization Factor (NF50) at Day 64; description: GMT of TNA NF50 at Day 64 in AV7909 study groups (Lots 1, 2 and 3) and BioThrax group. The outcome measure in AV7909 study groups was assessed for AV7909 lot-to-lot consistency, which was based on GMT TNA NF50 response at Day 64, wherein the 95% confidence interval (CI) for ratios of geometric mean titer (GMT) of TNA NF50 at Day 64 (seven weeks after second AV7909 vaccination) for each of the three AV7909 lot-to-lot comparisons had to be within equivalence margin of 0.5 and 2.0.; timeFrame: Day 64 (seven weeks after second AV7909 vaccination); measure: Percentage of Participants in AV7909 Lot 1, Lot 2 and Lot 3 Groups Achieving a TNA NF50 ≥0.56 on Day 64; description: Proportion of participants with TNA NF50 ≥0.56 at Day 64 in each AV7909 study groups (Lot 1, Lot 2, Lot 3). The assessment of the immune response in each study group was pre-defined as the lower bound of the two-sided 95% CI to be ≥40% for the percentage of AV7909 participants in each of the three lots achieving a TNA NF50 ≥0.56 at seven weeks after second AV7909 vaccination (Day 64).; timeFrame: Day 64 (seven weeks after second AV7909 vaccination); measure: Percentage of AV7909 Participants Achieving a TNA NF50 ≥0.56 on Day 64; description: Percentage of AV7909 participants (from all three AV7909 study groups pooled) achieving a TNA NF50 ≥0.56 on Day 64 (seven weeks after second AV7909 vaccination). The assessment of the immune response in AV7909 participants was pre-defined as the lower bound of the two-sided 95% CI for proportion of AV7909 participants with TNA NF50 ≥0.56 at Day 64 ≥40%.; timeFrame: Day 64 (seven weeks after second AV7909 vaccination); measure: Percentage of AV7909 Participants and BioThrax Participants With TNA NF50 ≥0.29 at Day 64; description: Proportion of AV7909 participants (in each AV7909 study groups) and BioThrax participants who achieved TNA NF50 ≥0.29 at Day 64. Non-inferiority of AV7909 vaccine to BioThrax vaccine at Day 64 was assessed as determined by the two-sided lower bound for the 95% CI of the difference in the percentage of AV7909 participants (three lots pooled) with a TNA NF50 ≥0.29 and the percentage of BioThrax participants with a TNA NF50 ≥0.29 being greater than -15%.; timeFrame: Day 64 (seven weeks after second AV7909 vaccination; five weeks after third BioThrax vaccination); measure: Incidence of Serious Adverse Events; description: Number of AV7909 participants or BioThrax participants who received at least one vaccination and reported serious adverse event(s) (SAEs) from the time of the first vaccination on Day 1 through Day 394.; timeFrame: Day 1 though Day 394

History coverage

Research sample: selected versions from May 2023 onward plus a preceding baseline where available. Only selected fields were retained; endpoint measures were truncated to 300 characters. This is not complete trial or sponsor history. Daily snapshots begin when collection starts.

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