deltatrials
Active Not Recruiting PHASE2 INTERVENTIONAL 2-arm NCT03285412

CDK 4/6 Inhibitor, Ribociclib, With Adjuvant Endocrine Therapy for ER-positive Breast Cancer (LEADER)

Phase II Study of CDK 4/6 Inhibitor, LEE011 (Ribociclib), in Combination With Adjuvant Endocrine Therapy at Varying Duration for ER-positive Breast Cancer (LEADER).

Sponsor: Massachusetts General Hospital

Conditions Breast Cancer
Interventions Endocrine therapy Ribociclib
Updated 18 times since 2017 Last updated: Dec 19, 2025 Started: Dec 12, 2017 Primary completion: Apr 30, 2026 Completion: Oct 31, 2026
This information is for research purposes only and is not medical advice. Consult a healthcare provider before making any medical decision.

A PHASE2 clinical study on Breast Cancer, this trial is ongoing. The trial is conducted by Massachusetts General Hospital and has accumulated 18 data snapshots since 2017. Oncology trials at this stage typically focus on safety, tolerability, and early efficacy signals.

Status Flow

~Oct 2017 – ~Apr 2018 · 6 months · monthly snapshot~Apr 2018 – ~Jun 2018 · 2 months · monthly snapshot~Jun 2018 – ~Jan 2019 · 7 months · monthly snapshot~Jan 2019 – ~Feb 2019 · 31 days · monthly snapshot~Feb 2019 – ~Sep 2019 · 7 months · monthly snapshot~Sep 2019 – ~Jun 2020 · 9 months · monthly snapshot~Jun 2020 – ~Nov 2020 · 5 months · monthly snapshot~Nov 2020 – ~Jan 2021 · 2 months · monthly snapshot~Jan 2021 – ~Mar 2021 · 59 days · monthly snapshot~Mar 2021 – ~Jun 2021 · 3 months · monthly snapshot~Jun 2021 – ~Nov 2021 · 5 months · monthly snapshot~Nov 2021 – ~Feb 2023 · 15 months · monthly snapshot~Feb 2023 – ~May 2024 · 15 months · monthly snapshot~May 2024 – ~Jul 2024 · 2 months · monthly snapshot~Jul 2024 – ~Sep 2024 · 2 months · monthly snapshot~Sep 2024 – ~Sep 2025 · 12 months · monthly snapshot~Sep 2025 – ~Jan 2026 · 4 months · monthly snapshot~Jan 2026 – present · 6 months · monthly snapshot

Change History

18 versions recorded

  1. Jan 2026 — Present [monthly]

    Active Not Recruiting PHASE2

  2. Sep 2025 — Jan 2026 [monthly]

    Active Not Recruiting PHASE2

    Status: Recruiting → Active Not Recruiting

  3. Sep 2024 — Sep 2025 [monthly]

    Recruiting PHASE2

  4. Jul 2024 — Sep 2024 [monthly]

    Recruiting PHASE2

  5. May 2024 — Jul 2024 [monthly]

    Recruiting PHASE2

▶ Show 13 earlier versions

  1. Feb 2023 — May 2024 [monthly]

    Recruiting PHASE2

  2. Nov 2021 — Feb 2023 [monthly]

    Recruiting PHASE2

  3. Jun 2021 — Nov 2021 [monthly]

    Recruiting PHASE2

  4. Mar 2021 — Jun 2021 [monthly]

    Recruiting PHASE2

  5. Jan 2021 — Mar 2021 [monthly]

    Recruiting PHASE2

  6. Nov 2020 — Jan 2021 [monthly]

    Recruiting PHASE2

    Status: Active Not Recruiting → Recruiting

  7. Jun 2020 — Nov 2020 [monthly]

    Active Not Recruiting PHASE2

    Status: Recruiting → Active Not Recruiting

  8. Sep 2019 — Jun 2020 [monthly]

    Recruiting PHASE2

  9. Feb 2019 — Sep 2019 [monthly]

    Recruiting PHASE2

  10. Jan 2019 — Feb 2019 [monthly]

    Recruiting PHASE2

  11. Jun 2018 — Jan 2019 [monthly]

    Recruiting PHASE2

  12. Apr 2018 — Jun 2018 [monthly]

    Recruiting PHASE2

    Status: Not Yet Recruiting → Recruiting

  13. Oct 2017 — Apr 2018 [monthly]

    Not Yet Recruiting PHASE2

    First recorded

Eligibility Summary

No eligibility information available.

Contact Information

Sponsor contact:
  • Massachusetts General Hospital
  • Novartis
Data source: Massachusetts General Hospital

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

Study Locations