Vepdegestrant (ARV-471/PF-07850327) + Palbociclib vs Letrozole + Palbociclib in ER(+)/HER2(-) Advanced Breast Cancer

Brief summary (registry, in English)

The purpose of this study is to understand the safety and effects of the study medicine vepdegestrant (ARV-471/PF-07850327) given together with palbociclib in advanced breast cancer. In particular, the study will compare the combination of vepdegestrant plus palbociclib to standard of care therapy (letrozole plus palbociclib). Both letrozole and palbociclib are medicines already used for treatment of breast cancer. Vepdegestrant is a new medicine under study. This study is seeking participants who have breast cancer that: * Have a locally advanced or metastatic disease and cannot be fully cured by surgery or radiation therapy. A metastatic disease is when disease has spread to other parts of the body. * Is sensitive to hormonal therapy such as tamoxifen. This is called estrogen receptor positive disease. * Have not received any prior medicine for advanced disease. Example medications include tamoxifen or letrozole or exemestane. The study will have an open-label SLI (study lead-in) before initiation of Phase 3 trial. During SLI, two dose levels of palbociclib in combination with vepdegestrant will be explored in parallel. Assignment to the palbociclib dose is by chance. Half of the participant will receive one dose and the other half another palbociclib dose. The purpose of SLI is to determine the recommended Phase 3 dose of palbociclib to be administered in combination with vepdegestrant. In the Phase 3, half of the participants will take vepdegestrant plus palbociclib while the other half will take letrozole plus palbociclib. In both SLI and Phase 3, participants will take the study medicines by mouth, with food, once a day. Participants will take the study medicines until breast cancer increase in size or side effects become too severe. Side effects refer to unwanted reactions to medications. Participants will visit the study clinic about once every 4 weeks.

What you commit to

• Study type: Interventional · Phase 3
• Participants enrolled: 59
• From 9 Aug 2023 to the primary completion date, 30 Dec 2026
• 29 sites in 10 countries
• Visits and tests: ask the trial team, the registry does not list them

Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.

Who cannot take part

Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.

Who the study is looking for

Age in the registry: 18 years to - · Sex: All · Does not accept healthy volunteers

Full criteria on ClinicalTrials.gov

Sites (29)

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