For Adults With Advanced/Metastatic HR+ HER2- Breast Cancer, Not Yet Treated: Join the FourLight-3 Study

About the Study

The FourLight-3 clinical trial compares a study treatment, atrimociclib combined with letrozole, against standard approved treatments. The clinical trial is for adults with advanced or metastatic HR-positive, HER2-negative breast cancer who have not received prior treatment for advanced/metastatic disease. Participants will be randomly assigned to a treatment group, attend regular clinic visits, and have tests and scans to monitor their health and response to treatment.

What the Study Involves

• This is a randomized, open-label Phase 3 clinical trial. Participants are randomly assigned to receive either the investigational treatment (atrimociclib plus letrozole) or study doctor’s choice of standard approved therapy
• Interested individuals will complete screening tests to confirm eligibility, including medical history review, blood tests, physical exam, heart activity tests, and scans to measure tumors. Only adults with advanced HR-positive, HER2-negative breast cancer who have not received prior treatment for advanced/metastatic disease may qualify
• Participants receive either atirmociclib plus letrozole, or standard approved therapy. Treatment is taken by mouth with regular dosing and clinic visits. The exact dose and schedule are determined by the study protocol
• Regular clinic visits are required for monitoring while you are on study treatment, including blood tests, scans to monitor tumor size, and health assessments. Additional procedures, such as biopsies, may be needed

The study includes follow-up visits and brief assessments on how you are doing after you end study treatment.. Additional time commitment may be required beyond standard care.

Participants may receive reimbursement for treatment-related costs, such as travel.

People may be eligible to join the FourLight‑3 study if they are 18 or older and have been diagnosed with hormone receptor–positive (HR+) and HER2‑negative advanced or metastatic breast cancer. This study is designed for individuals whose cancer returned after early-stage breast cancer treatment or newly diagnosed breast cancer that has spread beyond the breast and who have not yet received treatment for their advanced or metastatic disease.

Some people may not be able to join the FourLight‑3 study if certain health factors could affect their safety on study.. Individuals may be excluded if they have received previous treatment for advanced or metastatic breast cancer, or if they have other serious medical conditions that could interfere with participation, such as uncontrolled infections, significant heart or liver problems, or other active cancers. People may also be ineligible if they are unable to attend required on-site study visits or currently taking a prohibited medication. Final eligibility decisions are made by the study doctor after reviewing each person’s medical history and overall health.