A Phase III, Open-Label, Randomised Study to Assess the Efficacy and Safety of Extended Therapy With Camizestrant Versus Standard Endocrine Therapy (Aromatase Inhibitor or Tamoxifen) in Patients With ER+/HER2- Early Breast Cancer

Trial summary:

This is a Phase III open-label study to assess if camizestrant improves outcomes compared to standard endocrine therapy in patients with ER+/HER2 – early breast cancer with intermediate or high risk for disease recurrence who completed definitive locoregional therapy (with or without chemotherapy) and standard adjuvant endocrine therapy (ET) for at least 2 years and up to 5 years. The planned duration of treatment in either arm of the study is 60 months.

Receptor status / problem studied:

ER+/HER2 - early breast cancer

Inclusion criteria

  • Women and Men, ≥18 years at the time of screening (or per national guidelines)
  • Histologically confirmed ER+/HER2- early-stage resected invasive breast cancer with high or intermediate risk of recurrence, based on clinical-pathological risk features, as defined in the protocol.
  • Completed adequate (definitive) locoregional therapy (surgery with or without radiotherapy) for the primary breast tumour(s), with or without (neo)adjuvant chemotherapy
  • Completed at least 2 years but no more than 5 years (+3 months) of adjuvant ET (+/- CDK4/6 inhibitor)
  • Eastern Cooperative Oncology Group (ECOG) performance status of ≤ 1
  • Adequate organ and marrow function

Exclusion criteria

  • Inoperable locally advanced or metastatic breast cancer
  • Pathological complete response following treatment with neoadjuvant therapy
  • History of any other cancer (except non-melanoma skin cancer or carcinoma in situ of the cervix or considered at very low risk of recurrence per investigator judgement) unless in complete remission with no therapy for a minimum of 5 years from the date of randomisation
  • Any evidence of severe or uncontrolled systemic diseases which, in the investigator’s opinion precludes participation in the study or compliance
  • Known LVEF <50% with heart failure NYHA Grade ≥2.
  • Mean resting QTcF interval >480 ms at screening
  • Concurrent exogenous reproductive hormone therapy or non-topical hormonal therapy for non-cancer-related conditions
  • Any concurrent anti-cancer treatment not specified in the protocol with the exception of bisphosphonates (e.g. zoledronic acid) or RANKL inhibitors (eg, denosumab)
  • Previous treatment with camizestrant, investigational SERDs/investigational ER targeting agents, or fulvestrant
  • Currently pregnant (confirmed with positive serum pregnancy test) or breastfeeding
  • Patients with known hypersensitivity to active or inactive excipients of camizestrant or drugs with a similar chemical structure or class to camizestrant. In pre-/peri-menopausal female and male patients, known hypersensitivity or intolerance to LHRH agonists, that would preclude the patient from receiving any LHRH agonist

View more trial information

Open for recruitment

Trial Title



Breast cancer

Type of trial


Type of treatement

Medical Oncology





Principal Investigator
View all clinical trials


Contact us
Become a patient