Although treatments for breast cancer have improved, 20-30% of patients with early disease develop metastases (cancer that spreads to other parts of the body). Among the different types of breast cancer, hormone-sensitive cancers that do not overexpress the HER2 protein (HR+/HER2-) are the most common. For patients with this type of cancer, an endocrine treatment such as aromatase inhibitors, tamoxifen or fulvestrant, is often used and may be combined with drugs called CDK4/6 inhibitors, which help improve survival rate. However, when the cancer becomes resistant to these treatments, treatment strategies are more limited
A new drug, prifetrastat (PF-07248144), which targets KAT6 proteins, which play a role in the growth of cancer cells, has shown promising results. Indeed, associated with fulvestrant, it allowed to fight against cancer in some patients who had already received many treatments.
The UNLOCK-EPIBREAST study aims to investigate whether the combination of prifetrastat plus fulvestrant could offer a new therapeutic option for people with HR+/HER2- metastatic breast cancer who have already received endocrine therapy plus CDK4/6 inhibitors.
Patient must have signed the written informed consent prior to any study specific screening procedures.
Adult participants age ≥18 years.
Histological or cytological diagnosis of advanced or metastatic ER+HER2- breast cancer.
Participants must have progressive disease after at least 1 prior line of a CDK4/6 inhibitor and at least 1 prior line of endocrine therapy received in metastatic setting. Participants must not have received more than 3 prior lines of systemic therapies including up to 2 lines of cytotoxic chemotherapy for visceral disease in advanced or metastatic setting. Note that prior treatment with fulvestrant is permitted.
Participants with known symptomatic brain metastases requiring steroids. Participants with previously diagnosed brain metastases are eligible if they have completed their treatment and have recovered from the acute effects of radiation therapy or surgery prior to randomization, have discontinued corticosteroid treatment for these metastases for at least 3 weeks and are neurologically stable for 2 months (requires MRI confirmation).
Participants with advanced/metastatic, symptomatic, visceral spread, that are at risk of life-threatening complications in the short term (including participants with massive uncontrolled effusions [pleural, pericardial, peritoneal], pulmonary lymphangitis, and over 50% liver involvement). Note: Participants with indwelling catheter for drainage, or requirement for drainage no more frequently than once a month will be allowed.
Participants with any other active malignancy within 3 years prior to enrollment, except for adequately treated basal cell or squamous cell skin cancer, or carcinoma in situ. Other indolent cancers that do not interfere with assessment of primary cancer under study may be allowed with prior sponsor approval.
Major surgery within 3 weeks prior to randomization.
UNICANCER
Lead sponsor
Pfizer
Collaborator