Trial results
AI generated results summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
According to the results reported on ClinicalTrials.gov, this trial (NCT04075604) enrolled 23 people across three groups, testing different doses of a combination treatment (involving the drugs nivolumab and palbociclib) given before surgery for breast cancer. The groups were: Cohort 1 at Dose Level 1 (2 participants), Cohort 2 at Dose Level 1 (9 participants), and Cohort 2 at Dose Level 2 (12 participants). The trial had a two-part design — a safety testing phase followed by a planned randomised phase — but the reported data notes that the trial was closed after the safety phase, so the randomised phase never took place. The reported data shows that during the safety phase, the number of participants who experienced a "dose-limiting toxicity" (a side effect serious enough within the first treatment cycle to potentially limit the dose) was zero in Cohort 1 and zero in Cohort 2 at Dose Level 2, while 2 out of 9 participants in Cohort 2 at Dose Level 1 met this definition. Because the trial did not proceed to the randomised phase, no results were reported for the main planned outcome measure (how many participants had little or no cancer remaining after treatment). For the secondary measures, the proportion of participants whose tumours shrank significantly on scans was reported as 0% in Cohort 1, approximately 67% in Cohort 2 at Dose Level 1, and 75% in Cohort 2 at Dose Level 2. The proportion who had no detectable invasive cancer remaining at surgery (called a pathological complete response) was 0% in both Cohort 1 and Cohort 2 at Dose Level 1, and approximately 8% in Cohort 2 at Dose Level 2. Breast-conserving surgery rates were reported at 50%, 56%, and 50% across the three groups respectively. The reported data also shows that all participants in every group — 2, 9, and 12 respectively — experienced at least one adverse event (an unwanted medical occurrence during the study). These are the results as reported to ClinicalTrials.gov. They are not medical advice — always discuss what they mean for you with your doctor.
These are the results as reported to ClinicalTrials.gov, not medical advice. Verify independently with the trial site and discuss what they mean for you with your doctor.
Phase 2 Breast Cancer Trial, Completed
Who may be able to join
AI generated eligibility summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
Who might be able to join this trial:
- You have been newly diagnosed with breast cancer in one breast that has not yet been treated, is confirmed by biopsy to be ER-positive and HER2-negative, and the tumor is at least 2 cm in size.
- Your doctors have decided that hormone-blocking therapy (without chemotherapy) given before surgery is a suitable treatment option for you.
- You are able and willing to have surgery after the pre-surgery treatment, and you agree to provide tumor tissue samples at the start of the study, during treatment, and at the time of surgery.
- You are a woman who has been confirmed to not be able to become pregnant (confirm with trial site).
- You are in generally good overall health and are able to carry out normal daily activities, with at most minor limitations (as measured by a standard health scale used in clinical trials).
Who may not be able to join:
- You have already received any treatment for your current breast cancer, such as radiation, chemotherapy, or targeted therapy, or your doctors feel that chemotherapy before surgery is the best option for you.
- You have a history of, or currently have, an autoimmune disease or a condition that has required you to take steroid medications or immune-suppressing drugs in the past 2 years.
- You have received certain hormone therapies or CDK4/6 inhibitor drugs for breast cancer within the past 5 years, or have previously been treated with certain immunotherapy drugs (such as checkpoint inhibitors), or have had an allergic reaction to any of the study medications.
- You have had another cancer that was active within the past 3 years, or you have serious or poorly controlled health conditions.
- You have a personal history of unexplained fainting, certain heart rhythm problems (such as ventricular tachycardia, ventricular fibrillation, long or short QT syndrome, or Brugada syndrome), or sudden cardiac arrest.
Important: Always verify eligibility with the trial site directly before applying.
Based on publicly available eligibility criteria from ClinicalTrials.gov. Verify directly with the trial site before acting. This is not medical advice.
GP referral letter
Print a one-page summary to share with your doctor.
Trial details
Where this trial is recruiting
2 site(s) in Australia. Confirm current status and contact details directly with the trial site.
Primary endpoints
The Number of Participants With Dose Limiting Toxicities (DLT) in the Safety Run-in Phase; Residual Cancer Burden (RCB) 0-1 Rate in the Randomized Phase
Can't join this trial?
Data last synced from ClinicalTrials.gov: 2 July 2026. Trial status can change. Always verify current status directly with the trial site before making any decision.