NCT07284654Phase 3Active not recruiting

Safety, Tolerability, and Immunogenicity of VAX-31 in Adults ≥50 Years With Immunobridging to Adults 18-49

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 completion2027-01Estimated

Enrollment · participants4049Actual

Source updated2026-05-15Last update listed in the registry record

Version history

Changes to this trial

Last 12 months

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Posted 2026-03-31 · 3 fields changed

Participant count type changed

− Before

~~Estimated~~

+ After

Actual

Enrollment · participant count changed

− Before

~~4000 participants (planned)~~

+ After

4049 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
PCV20BiologicalAlso known as Prevnar 20
PCV21BiologicalAlso known as Capvaxive

Primary outcomes · main study measures

Read the study measures

measure: Serotype-specific OPA geometric mean titers (GMT) in 50 year olds and above; timeFrame: 1 month after 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 serious adverse events (SAE), new onset of chronic illness (NOCI), and medically attended adverse events (MAAE); timeFrame: up to 6 Months after vaccination; measure: Serotype-specific OPA geometric mean titers (GMT) in 18 to 49 year olds and 50 to 64 year olds; timeFrame: 1 month 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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