deltatrials
Recruiting PHASE4 INTERVENTIONAL 1-arm NCT03346772

Study of Immune Responses to Influenza Vaccination

Sponsor: University of Pennsylvania

Updated 12 times since 2017 Last updated: Aug 13, 2025 Started: Oct 20, 2017 Primary completion: Jul 1, 2026 Completion: Jul 1, 2026
This information is for research purposes only and is not medical advice. Consult a healthcare provider before making any medical decision.

Listed as NCT03346772, this PHASE4 trial focuses on Influenza Vaccination and remains actively recruiting participants. Sponsored by University of Pennsylvania, it has been updated 12 times since 2017, reflecting substantial change activity. This study is part of the global effort to build evidence for infectious disease interventions.

Status Flow

~Dec 2017 – ~Jun 2018 · 6 months · monthly snapshotRecruiting~Jun 2018 – ~Feb 2019 · 8 months · monthly snapshotRecruiting~Feb 2019 – ~Jul 2020 · 17 months · monthly snapshotEnrolling By Invitation~Jul 2020 – ~Sep 2020 · 2 months · monthly snapshotEnrolling By Invitation~Sep 2020 – ~Jan 2021 · 4 months · monthly snapshotEnrolling By Invitation~Jan 2021 – ~May 2021 · 4 months · monthly snapshotEnrolling By Invitation~May 2021 – ~Nov 2022 · 18 months · monthly snapshotRecruiting~Nov 2022 – ~Nov 2023 · 12 months · monthly snapshotRecruiting~Nov 2023 – ~Jul 2024 · 8 months · monthly snapshotRecruiting~Jul 2024 – ~Sep 2024 · 2 months · monthly snapshotRecruiting~Sep 2024 – ~Sep 2025 · 12 months · monthly snapshotRecruiting~Sep 2025 – present · 10 months · monthly snapshotRecruiting

Change History

12 versions recorded
  1. Sep 2025 — Present [monthly]

    Recruiting PHASE4

  2. Sep 2024 — Sep 2025 [monthly]

    Recruiting PHASE4

  3. Jul 2024 — Sep 2024 [monthly]

    Recruiting PHASE4

  4. Nov 2023 — Jul 2024 [monthly]

    Recruiting PHASE4

  5. Nov 2022 — Nov 2023 [monthly]

    Recruiting PHASE4

Show 7 earlier versions
  1. May 2021 — Nov 2022 [monthly]

    Recruiting PHASE4

    Status: Enrolling By InvitationRecruiting

  2. Jan 2021 — May 2021 [monthly]

    Enrolling By Invitation PHASE4

  3. Sep 2020 — Jan 2021 [monthly]

    Enrolling By Invitation PHASE4

  4. Jul 2020 — Sep 2020 [monthly]

    Enrolling By Invitation PHASE4

  5. Feb 2019 — Jul 2020 [monthly]

    Enrolling By Invitation PHASE4

    Status: RecruitingEnrolling By Invitation

  6. Jun 2018 — Feb 2019 [monthly]

    Recruiting PHASE4

  7. Dec 2017 — Jun 2018 [monthly]

    Recruiting PHASE4

    First recorded

Oct 2017

Trial started

Per CT.gov start date — pre-dates our first snapshot

Eligibility Summary

No eligibility information available.

Contact Information

Sponsor contact:
  • University of Pennsylvania
Data source: University of Pennsylvania

For direct contact, visit the study record on ClinicalTrials.gov .

Study Locations