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Key Record Dates

ClinicalTrials.gov Identifier: NCT02957890
Brief Title: Immunogenicity of Twice-annual Influenza Vaccination in Older Adults in Hong Kong (RETAIN)

First Submitted : October 31, 2016
First Submitted that Met QC Criteria : November 3, 2016
First Posted : November 8, 2016 (Estimate)

Last Update Submitted that Met QC Criteria : September 21, 2021
Last Update Posted : September 22, 2021