This is a multicenter, open-label, non-controlled, phase I study to investigate the tolerability and safety of ONO-4578 used in combination with standard-of-care letrozole and a CDK4/6 inhibitor (palbociclib or Abemaciclib) as first-line endocrine therapy in postmenopausal patients with metastatic or recurrent hormone receptor-positive, HER2-negative breast cancer.
Age range
20 Years
Sex
FEMALE
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
Adverse events
Timeframe: Through study completion, an average of 4 year
Serious adverse events
Timeframe: Through study completion, an average of 4 year
Dose-limiting toxicity (Tolerability Confirmation part only)
Timeframe: 28 days
Laboratory abnormality profile of Drugs as measured by incidence and severity of clinical laboratory abnormalities
Timeframe: Through study completion, an average of 4 year
Body temperature
Timeframe: Through study completion, an average of 4 year
Pulse rate
Timeframe: Through study completion, an average of 4 year
Systolic/diastolic blood pressure
Timeframe: Through study completion, an average of 4 year
Saturation of Percutaneous Oxygen (SpO2)
Timeframe: Through study completion, an average of 4 year
Weight
Timeframe: Through study completion, an average of 4 year
Eastern Cooperative Oncology Group Performance Status
Timeframe: Through study completion, an average of 4 year
Chest X-ray
Timeframe: Through study completion, an average of 4 year
CT scan
Timeframe: Through study completion, an average of 4 year
12-lead electrocardiography (Heart rate)
Timeframe: Through study completion, an average of 4 year
12-lead electrocardiography (PR interval)
Timeframe: Through study completion, an average of 4 year
12-lead electrocardiography (RR interval)
Timeframe: Through study completion, an average of 4 year
12-lead electrocardiography (QRS width)
Timeframe: Through study completion, an average of 4 year
12-lead electrocardiography (QT interval)
Timeframe: Through study completion, an average of 4 year