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BYL719 and Letrozole in Post-Menopausal Patients With Hormone Receptor-Positive Metastatic Breast Cancer

Phase 1
Active, not recruiting
Conditions
Stage IV Breast Cancer
Estrogen Receptor-positive Breast Cancer
HER2-negative Breast Cancer
Invasive Ductal Breast Carcinoma
Progesterone Receptor-positive Breast Cancer
Recurrent Breast Cancer
Interventions
Drug: PI3K inhibitor BYL719
Other: laboratory biomarker analysis
Other: pharmacological studies
Registration Number
NCT01791478
Lead Sponsor
Vanderbilt-Ingram Cancer Center
Brief Summary

This phase I trial studies the side effects and best dose of the PI3K inhibitor BYL719 when given together with letrozole in treating patients with hormone receptor-positive metastatic breast cancer. The PI3K inhibitor BYL719 may stop the growth of tumor cells by blocking some of the proteins needed for cell growth. Hormone therapy using letrozole may fight breast cancer by blocking the use of estrogen by the tumor cells. Giving the PI3K inhibitor BYL719 together with letrozole may kill more tumor cells

Detailed Description

PRIMARY OBJECTIVE: To determine the safety and tolerability of BYL719 given in combination with endocrine therapy in post-menopausal patients with hormone receptor-positive metastatic breast cancer by determining:

I. Dose limiting toxicities (DLTs) during the first 4 weeks of treatment (cycle 1).

II. Maximum tolerated dose (MTD) of BYL719 (PI3K inhibitor BYL719) given in combination with letrozole.

III. Highest tolerated dose - ability to tolerate BYL719 with letrozole for a total of 8 weeks without development of:

* Hyperglycemia (fasting glucose \> 200 mg/dL) for more than 2 weeks in a row despite optimal medical treatment

* CTC Grade 3 or \> rash for more than 2 weeks in a row despite optimal medical treatment

* CTC Grade 2 or \> GI toxicity for more than 2 weeks in a row despite optimal medical treatment

* CTC Grade 2 or \> serum creatinine, bilirubin, AST, ALT elevation from baseline for more than 2 weeks in a row despite optimal medical treatment

SECONDARY OBJECTIVES: To determine the anti-tumor effect of the combinations of endocrine therapy with BYL719 in post-menopausal patients with hormone receptor-positive metastatic breast cancer by assessing:

I. Progression free survival (PFS). II. Objective response rate (ORR). III. Clinical benefit rate (complete response \[CR\]+partial response \[PR\]+stable disease \[SD\] \>= 6 months).

EXPLORATORY OBJECTIVES:

I. Pharmacokinetics of BYL719 in combination with letrozole: Plasma concentration-time profiles and derived basic pharmacokinetic (PK) parameters of BYL719 and letrozole, including but not limited to area under the plasma concentration-time curve from time zero to the last measurable concentration (AUC0-tlast), AUC curve to infinite time (AUC0-inf), maximum observed concentration (Cmax), time to peak concentration (Tmax), clearance over bioavailability (CL/F), apparent volume of distribution (Vz/F) and the terminal half-life (t1/2) and other PK parameters if deemed appropriate.

II. Correlation of response with alterations of the PI3K pathway: Mutational analysis of PIK3CA (exons 9 and 20), phosphatase and tensin homolog (PTEN), and AKT1 in formalin-fixed paraffin blocks (FFPB) from previous surgeries or fresh-frozen biopsies (if available) on all patients enrolled in the trial.

OUTLINE: This is an open-label phase Ib dose-escalation study of the PI3K inhibitor BYL719 in combination with letrozole in post-menopausal patients with ER+ metastatic breast cancer.

Patients receive BYL719 orally (PO) once daily (QD) and letrozole PO QD. Courses repeat every 4 weeks in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed up for 4 weeks.

Recruitment & Eligibility

Status
ACTIVE_NOT_RECRUITING
Sex
Female
Target Recruitment
46
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Treatment (PI3K inhibitor BYL719, letrozole)PI3K inhibitor BYL719Patients receive PI3K inhibitor BYL719 PO QD and letrozole PO QD. Courses repeat every 4 weeks in the absence of disease progression or unacceptable toxicity.
Treatment (PI3K inhibitor BYL719, letrozole)letrozolePatients receive PI3K inhibitor BYL719 PO QD and letrozole PO QD. Courses repeat every 4 weeks in the absence of disease progression or unacceptable toxicity.
Treatment (PI3K inhibitor BYL719, letrozole)laboratory biomarker analysisPatients receive PI3K inhibitor BYL719 PO QD and letrozole PO QD. Courses repeat every 4 weeks in the absence of disease progression or unacceptable toxicity.
Treatment (PI3K inhibitor BYL719, letrozole)pharmacological studiesPatients receive PI3K inhibitor BYL719 PO QD and letrozole PO QD. Courses repeat every 4 weeks in the absence of disease progression or unacceptable toxicity.
Primary Outcome Measures
NameTimeMethod
Maximum tolerated dose of BYL719 in combination with letrozole4 weeks

Highest dose of BYL719 tested in which a DLT is experienced by 0 out of 3 or 1 of 6 patients, based on the NCI Common Toxicity Criteria for Adverse Events (CTCAE) version 4.0

Secondary Outcome Measures
NameTimeMethod
Highest tolerated dose of BYL719 in combination with letrozole8 weeks

Highest dose of BYL719 without CTC Grade \> 2 hyperglycemia(fasting glucose \> 200 mg/dL) for \> 2 weeks, Grade \> 3 rash for \> 2 weeks , Grade \> 2 gastrointestinal toxicity for \> 2 weeks and Grade \> 2 creatinine, bilirubin, AST, ALT for \> 2 weeks.

Clinical benefit rateAt 6 months of study treatment

Per Response Evaluation Criteria In Solid Tumors (RECIST) version 1.1; percentage of patients with complete response (CR) + partial response (PR) + stable disease (SD) for more than 6 months.

Overall progression-free survivalUp to 4 weeks after interruption of study treatment

Duration from on-study date to date of progressive disease.

Overall responseEvery 8 weeks to interruption of treatment

Per RECIST version 1.1. number of patients each with CR, PR, SD, and progressive disease (PD) as their best response.

Worst grade toxicitiesUp to 4 weeks after interruption of study treatment

Number of patients with worst-grade toxicity at each of five grades (grade 1, least severe; to grade 5, most severe) following NCI Common Toxicity Criteria 4.0.

Trial Locations

Locations (2)

Vanderbilt-Ingram Cancer Center

🇺🇸

Nashville, Tennessee, United States

Massachusetts General Hospital, Dana-Farber Cancer Institute

🇺🇸

Boston, Massachusetts, United States

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