for people ages 18 years and up (full criteria)
at San Francisco, California and other locations
study started
estimated completion



Some human epidermal growth factor receptor 2 (HER-2) breast cancer patients do not respond or become resistant to current treatment. DS-8201a is a new experimental product that is a combination of an antibody and a drug. It has not yet been approved for use. DS-8201a may slow down tumor growth. This might improve outcomes for these patients.

Official Title

A Phase 2, Multicenter, Open-Label Study of DS-8201a, an Anti-HER2-Antibody Drug Conjugate (ADC) for HER2-Positive, Unresectable and/or Metastatic Breast Cancer Subjects Previously Treated With T-DM1 (DESTINY-Breast01)


Breast Cancer HER-2 positive breast cancer Metastatic or Unresectable Resistant or refractory to T-DM1 DESTINY - Breast 01 Trastuzumab deruxtecan T-DXd Breast Neoplasms


You can join if…

Open to people ages 18 years and up

  • Men or women the age of majority in their country
  • Has pathologically documented breast cancer that:
  • is unresectable or metastatic
  • has HER2 positive expression confirmed per protocol
  • Has an adequate tumor sample
  • Has at least one measurable lesion per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1
  • Has protocol-defined adequate cardiac, renal and hepatic function
  • Agrees to follow protocol-defined method(s) of contraception

You CAN'T join if...

  • Has a medical history of myocardial infarction, symptomatic congestive heart failure (CHF) (NYHA classes II-IV), unstable angina or serious cardiac arrhythmia
  • Has a corrected QT interval (QTc) prolongation to > 450 millisecond (ms) in males and > 470 ms in females
  • Has a medical history of clinically significant lung disease
  • Is suspected to have certain other protocol-defined diseases based on imaging at screening period
  • Has history of any disease, metastatic condition, drug/medication use or other condition that might, per protocol or in the opinion of the investigator, compromise:
  • safety or well-being of the participant or offspring
  • safety of study staff
  • analysis of results


  • University of California San Francisco
    San Francisco California 94115 United States
  • Sansum Clinic
    Santa Barbara California 93105 United States


in progress, not accepting new patients
Start Date
Completion Date
Daiichi Sankyo, Inc.
Phase 2
Study Type
Last Updated