# COVID-19 Immunity and Changes Over Time

> **NCT05271669** · — · RECRUITING · sponsor: **Chinese University of Hong Kong** · enrollment: 1350 (estimated)

## Conditions studied

- COVID-19

## Interventions

_None listed._

## Key facts

- **NCT ID:** NCT05271669
- **Lead sponsor:** Chinese University of Hong Kong
- **Sponsor class:** OTHER
- **Phase:** —
- **Study type:** OBSERVATIONAL
- **Status:** RECRUITING
- **Start date:** 2022-06-06
- **Primary completion:** 2026-07
- **Final completion:** 2027-01
- **Target enrollment:** 1350 (ESTIMATED)
- **Last updated:** 2026-03-18


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT05271669

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT05271669, "COVID-19 Immunity and Changes Over Time". Retrieved via AI Analytics 2026-08-09 from https://api.ai-analytics.org/clinical/NCT05271669. Licensed CC0.

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*[Clinical trials dataset](/datasets/clinical-trials) · CC0 1.0*