A Phase Ib/II, Multicenter Study of the Combination of LEE011 and BYL719 With Letrozole in Adult Patients With Advanced ER+ Breast Cancer
Official Summary
The purpose of this trial is to inform the future clinical development of the two investigational agents in ER+ breast cancer, LEE011 (CDK4/6 inhibitor) and BYL719 (PI3K-alpha inhibitor). This is a multi-center, open-label Phase Ib study. The Phase Ib dose escalation will estimate the MTD and/or RP2D for three regimens: two double combinations, LEE011 with letrozole and BYL719 with letrozole, followed by triple combinations of LEE011 + BYL719 with letrozole (Arms 3 and 4). The Phase Ib dose escalation part will be followed by Phase Ib dose expansions to further characterize the safety, tolerability, PK and preliminary clinical anti-tumor activity of the combinations. Optional crossover for patients who have progressed while on dose escalation or dose expansion with doublet treatment on Arms 1 or 2 to be treated with the triplet combination (Arm 3) after the determination of the RP2D for Arm 3; is no longer permitted after protocol amendment 6. Approximately 270 adult women with ER+/HER2- locally advanced or metastatic breast cancer will be enrolled.
Study Design
- Study Type: INTERVENTIONAL
- Allocation: RANDOMIZED
- Model: PARALLEL
- Masking: NONE
- Enrollment: 255 participants
Interventions
- DRUG: LEE011 — LEE011 - 28 day cycles (21 days followed by a 7 day break) for Arms 1, 3. LEE011 28 days cycles (continuous) Arm 4.
- DRUG: Letrozole — Letrozole 2.5 mg/day
- DRUG: BYL719 — BYL719 - 28 days cycle (continuous) for Arm 2; 3 and 4
Primary Outcomes
- Incidence of Dose limiting toxicities (DLTs) - Phase lb only (28 days)
- Safety and tolerability (Average 18 months)
- PK profiles of LEE011 and letrozole (18 months)
Secondary Outcomes
- Safety and tolerability of LEE011 in combination with letrozole, BYL719 in combination with letrozole, and the triple combination of LEE011 +BYL719 with letrozole (Average 24 months)
- Plasma concentration-time profiles of LEE011, BYL719 and letrozole (Average 24 months)
- Overall Response Rate (ORR) (Average 24 months)
- Duration of Response (DOR) (Average 24 months)
- Progression Free Survival (PFS) (Average 24 months)
Eligibility Criteria
Inclusion Criteria: * Postmenopausal, Estrogen-receptor positive and/or Progesterone-receptor positive breast cancer * Phase Ib dose escalation only: Any number of prior lines of endocrine therapy is allowed with the exception of cytotoxic therapy which is limited to one prior line administered in the advanced (metastatic or locally advanced) setting. * Phase Ib dose expansions Arms 1, 2 and 3 * No prior systemic treatment in the advanced (metastatic or locally advanced) setting with the exception of treatment with letrozole for a maximum of one month prior to starting study treatment. * Patients who received (neo)adjuvant therapy for breast cancer are eligible. Prior therapy with letrozole or anastrozole in the (neo)adjuvant setting is permitted if the disease-free interval is greater than 12 months from the completion of treatment. Exclusion Criteria: * HER2-overexpression in the patient's tumor tissue * Patients with active CNS or other brain metastases * Major surgery within 2 weeks * Acute or chronic pancreatitis * Bilateral diffuse lymphangitic carcinomatosis * Another malignancy within 3 years * Receiving hormone replacement therapy that cannot be discontinued * Impaired cardiac function * Patients with clinically manifest diabetes mellitus (treated and/or clinical signs or with fasting glucose ≥ 126 mg/dL / 7.0 mmol/L or hemoglobin A1c \>6.5%), history of gestational diabetes mellitus or documented steroid-induced diabetes mellitus. * Other protocol-defined inclusion/exclusion criteria may apply
Trial Locations
- Univ of California at San Diego Moores Cancer Ctr, San Diego, California, United States
- UCSF Medical Center, San Francisco, California, United States
- H Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States
- Massachusetts General Hospital SC-5, Boston, Massachusetts, United States
- Massachusetts General Hospital, Boston, Massachusetts, United States
- Sarah Cannon Research Institute, Nashville, Tennessee, United States
- Vanderbilt University Medical Ctr, Nashville, Tennessee, United States
- Texas Oncology, Amarillo, Texas, United States
- Mays Cancer Ctr Uthsa Mdacc, San Antonio, Texas, United States
- Northwest Medical Specialties, Tacoma, Washington, United States
- ...and 10 more locations
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AI-generated analysis for educational purposes only. This is not medical advice. Discuss clinical trial participation with your doctor. Data sourced from ClinicalTrials.gov.