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Ciara O'Sullivan, M.B., B.Ch.

  1. Oncologist


  1. Rochester, Minnesota


  1. Brain metastasis
  2. Breast cancer
  3. HER2-positive breast cancer
  • HER2-positive breast cancer
  • Endocrine resistance
  • Breast cancer brain metastases
  • Phase I trials
  1. 2005
    MB BCh/BAO - Medicine (MB BCh BAO; Hons)University College Dublin
  2. 1998
    Diploma - (Leaving Certificate)The Institute of Education Secondary School


  1. 2017
    General MedicineRoyal College of Physicians of Ireland

Awards and honors

  1. 2023
    Poster Category FinalistMayo Clinic Comprehensive Cancer Center
  2. 2022
    Top Performer AwardMayo Clinic
  3. 2021
    Invited DiscussantSan Antonio Breast Cancer Symposium (SABCS)
  4. 2021
    Study ChairA011801 CompassHER2 Residual Disease (RD), a Double-Blinded, Phase III Randomized Trial of T-DM1 and placebo (pb) Compared with T-DM1 and Tucatinib
  5. 2018
    Career Development AwardASCO Conquer Cancer Foundation
  6. 2017
    Invited ParticipantASCO/American Association for Cancer Research (AACR), Methods in Clinical Cancer Research
  7. 2017
    Certificate of Appreciation for Dictation ExcellenceMayo Clinic
  8. 2014
    Merit AwardASCO Conquer Cancer Foundation
  9. 2014
    Highest scoring candidate of NCI fellows completing ASCO in-training examASCO In-Training Exam (ASCO ITE)
  10. 2013
    Clinical Scholars ScholarshipSan Antonio Breast Cancer Symposium (SABCS)
  11. 2012
    Highest scoring candidate of National Cancer Institute (NCI) fellows completing ASCO in-training examASCO In-Training Exam (ASCO ITE)
  12. 2011
    Highest scoring candidate in an Irish cohort of medical oncologists completing ASCO in-training examASCO In-Training Exam (ASCO ITE)
  13. 2010
    Highest scoring candidate in an Irish cohort of medical oncologists completing American Society of Clinical Oncology (ASCO) in-training examASCO In-Training Exam (ASCO ITE)
  14. 2006
    Best Clinical Tutor Runner-upUniversity College Dublin
  15. 2000
    Trinity College Dublin Entrance Exhibition AwardTrinity College
  16. 1997
    Best French StudentThe Institute of Education Secondary School

Professional memberships

  1. 2024 - present
    Founder and ModeratorGender-Specific and Overall Wellness/Burnout in Physicians
  2. 2023 - present
    Advisory BoardBreast Cancer U.S. KOL (Seagen/Pfizer)
  3. 2023 - present
    Advisory BoardDato-DXd SABCS
  4. 2023 - present
    Member, Clinical & Translational ResearcherMayo Clinic Comprehensive Cancer Center, Oncology Research Committee
  5. 2023 - present
    Study Arm Chaperone/Principal InvestigatorISPY2.2 Trial (Amendment 35)
  6. 2023 - present
    Invited ParticipantBreast International Group (BIG)-NCTN
  7. 2022 - present
    Steering Committee MemberAstraZeneca ENHERTU
  8. 2022 - present
    MemberMayo Clinic Institutional Review Board (IRB)
  9. 2022 - present
    Co-ChairMayo Clinic HER2+ Breast Cancer Working Group
  10. 2022 - present
    Podcast HostAcademic and Community Clinical Research United (ACCRU)
  11. 2022 - present
    Steering Committee MemberHER2CLIMB-05 Clinical Trial (NCT05132582)
  12. 2022 - present
    Alliance Study ChampionEA1211, Interim FDG-PET CT for PreDIcting Response of HER2+ Breast Cancer to Neoadjuvant Therapy: DIRECT trial concept
  13. 2021 - 2023
    MemberNCI Breast Cancer Steering Committee, neoSTEEP Working Group
  14. 2021 - present
    Grant ReviewerMayo Clinic Breast Cancer and Ovarian Cancer SPORE
  15. 2021 - present
    Study ChairA011801 (CompassHER2 RD), FDA Registration Trial
  16. 2021 - present
    Principal InvestigatorTAEK-VAC-HerBy-001: TAEK-VAC-HerBy Vaccine in Advanced HER2+ Tumors
  17. 2021 - present
    Study ChairAlliance for Clinical Trials in Oncology
  18. 2020 - 2022
    Principal InvestigatorT-DM1 With or Without Abemaciclib for the Treatment of HER2-Positive Metastatic Breast Cancer Trial
  19. 2020 - present
    InterviewerMayo Clinic Breast Oncology Surgical Fellowship
  20. 2020 - present
    Alliance Study ChampionEA1181, (CompassHER2-pCR): Preoperative THP and Postoperative HP in Patients Who Achieve a Pathologic Complete Response
  21. 2020 - present
    Steering Committee MemberSGNTUC-028: A Randomized, Double-blind, Phase 3 Study of Tucatinib or Placebo in Combination with Trastuzumab and Pertuzumab as Maintenance Therapy for Metastatic HER2+ Breast Cancer (HER2CLIMB-05)
  22. 2020 - present
    Principal InvestigatorSMX20-001: An Open-label, Multicenter Study Evaluating the Safety of Lasofoxifene in Combination with Abemaciclib for the Treatment of Pre- and Postmenopausal Women with Locally Advanced or Metastatic ER+/HER2- Breast Cancer and Have an ESR1 Mutation
  23. 2019 - 2021
    ASCO Trainee and Early Career Council, Career Conversations, MentorAmerican Society for Clinical Oncology (ASCO)
  24. 2019 - present
    Principal InvestigatorTBCRC 022: A Phase II Trial of HKI-272 (Neratinib), Neratinib and Capecitabine, and Neratinib and Ado-Trastuzumab Emtansine (T-DM1) for Patients with Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Breast Cancer and Brain Metastases
  25. 2017 - present
    MemberMayo Clinic Women's Cancer Program
  26. 2017 - present
    Breast Committee MemberAlliance for Clinical Trials in Oncology
  27. 2017 - 2021
    Principal InvestigatorECTx: Minnelide 101 (MCR)- A Phase I, Multi-center, Open-label, Dose-escalation, Safety, Pharmacokinetic, and Pharmacodynamic Study of Minnelide(TM) Capsules given alone or in combination with Protein-Bound Paclitaxel
  28. 2017 - present
    MemberMayo Clinic Comprehensive Cancer Center, Women's Cancer Program
  29. 2017 - present
    Co-Principal InvestigatorPROMISE Trial
  30. 2017 - present
    Principal InvestigatorA Phase I Study of a Combination of MM-398 and Veliparib in Solid Tumors
  31. 2017 - present
    Principal InvestigatorNRG-BR004, A Randomized, Double-Blind, Phase III Trial of Taxane/Trastuzumab/Pertuzumab with Atezolizumab or Placebo in First-Line HER2-Positive Metastatic Breast Cancer
  32. 2017 - present
    MemberAlliance for Clinical Trials in Oncology
  33. 2016 - present
    MemberAmerican Association for Cancer Research (AACR)
  34. 2016 - 2021
    Principal InvestigatorA Multicenter, Open-label, Phase II Study of Imprime PGG and Pembro in Subjects with Adv Melanoma Failing Treatment with CPI or TNBC Failing Front-line Chemo for Metastatic Disease / BT-CL-PGG-MEL/BCA-1621/MK3475 PN-545
  35. 2016 - present
    Principal InvestigatorA Phase II Open-label, Randomized Study of PARP Inhibition (Olaparib), Either Alone or in Combination with Anti-PDL1 Therapy (Atezolizumab; MPDL3280A) in Homologous DNA Repair (HDR) Deficient Triple Negative Breast Cancer (TNBC)
  36. 2016 - present
    Principal InvestigatorI3Y-MC-JPBZ monarcHER: A Phase II, Randomized, Multicenter, 3-Arm, Open-label Study to Compare the Efficacy of Abemaciclib Plus Trastuzumab with or without Fulvestrant to Standard-of-Care Chemotherapy of Physician's Choice Plus Trastuzumab
  37. 2016 - present
    Principal InvestigatorS1416, Phase II Randomized Placebo-controlled Trial of Cisplatin with or without ABT-888 (Velparib) in Metastatic Triple-Negative Breast Cancer and/or BRCA Mutation-Associated Breast Cancer, with or without Brain Metastases
  38. 2014 - 2016
    Medical Oncology Quality Assurance Committee memberNational Institutes of Health (NIH)
  39. 2014 - 2016
    CCR-FYI Steering CommitteeNational Institutes of Health (NIH)
  40. 2013 - 2016
    MemberThe Wild Geese Network of Irish Scientists in North America
  41. 2013 - 2016
    ClinFelcom, NCI Clinical Fellows CommitteeNational Institutes of Health (NIH)
  42. 2010 - present
    MemberEuropean Society of Medical Oncology (ESMO)
  43. 2010 - present
    MemberAmerican Society for Clinical Oncology (ASCO)
  44. 2009 - 2012
    MemberIrish Society of Medical Oncology (ISMO)
  45. 2008 - present
    MemberRoyal College of Physicians of Ireland (RCPI)