NCT07425392Phase 3Active not recruiting

Safety, Tolerability, and Immunogenicity of VAX-31 in Adults ≥50 Years With Prior Pneumococcal Vaccination

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 completion2027-03Estimated

Enrollment · participants752Actual

Source updated2026-06-30Last update listed in the registry record

Version history

Changes to this trial

Last 12 months

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Posted 2026-05-14 · 3 fields changed

Participant count type changed

− Before

~~Estimated~~

+ After

Actual

Enrollment · participant count changed

− Before

~~720 participants (planned)~~

+ After

752 participants (actual)

Recruitment status changed

− Before

~~Recruiting~~

+ After

Active not recruiting

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Study details

Conditions studied

Pneumococcal Vaccines

Treatments or interventions studied

31-valent pneumococcal conjugate vaccineBiological
PCV20Biological

Primary outcomes · main study measures

Read the study measures

measure: Serotype-specific OPA geometric mean titers (GMT); timeFrame: 1 month after VAX-31 vaccination; measure: Serotype-specific OPA geometric mean fold rise (GMFR) from baseline; timeFrame: 1 month after VAX-31 vaccination; measure: Percentage of subjects reporting solicited local adverse events (AE) (redness, swelling, and pain at injection site); timeFrame: up to 7 days after vaccination; measure: Percentage of subjects reporting solicited systemic AE (fever, headache, fatigue, muscle pain, and joint pain); timeFrame: up to 7 days after vaccination; measure: Percentage of subjects reporting unsolicited AE; timeFrame: up to 31 days after vaccination; measure: Percentage of subjects reporting new onset of chronic illness (NOCI), medically attended AE (MAAE), and serious adverse events (SAE); timeFrame: up to 6 months after vaccination

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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