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BYL719 Plus Letrozole or Exemestane for Patients With Hormone-Receptor Positive Locally-Advanced Unresectable or Metastatic Breast Cancer

A Phase I Trial of BYL719 Plus Letrozole or Exemestane for Patients With Hormone-Receptor Positive Locally-Advanced Unresectable or Metastatic Breast Cancer

Status
Completed
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01870505
Enrollment
52
Registered
2013-06-06
Start date
2013-05-31
Completion date
2022-02-28
Last updated
2024-12-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Metastatic or Locally-advanced Unresectable Breast Cancer

Keywords

BYL719, Letrozole, Exemestane, 13-027

Brief summary

The purpose of this study is to test the safety of a drug called BYL719 at different dose levels. The investigators want to find out what effects, good and/or bad, BYL719 has on the patient and breast cancer. BYL719 will be given with either letrozole or exemestane to patients with HR+ locally-advanced or metastatic breast cancer. When the recommended phase II dose of BYL719 in combination with letrozole or exemestane has been determined in the dose-finding phase, an additional 10 patients will be enrolled onto each arm in an expansion phase of the study. The purpose of the expansion phase is to further define the safety and feasibility of BYL719 in combination with letrozole or exemestane at the recommended phase II dose, and to estimate efficacy.

Interventions

DRUGBYL719
DRUGLetrozole
DRUGExemestane

Sponsors

Novartis Pharmaceuticals
CollaboratorINDUSTRY
Memorial Sloan Kettering Cancer Center
Lead SponsorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Women age ≥ 18 years * Willing and able to comply with scheduled visits, treatment plan and laboratory tests * Willing and able to consent for biopsy of locally-advanced or metastatic breast cancer prior to treatment * Metastatic or locally-advanced unresectable breast cancer (includes metastatic or locally-advanced unresectable breast cancer which is diagnosed while on adjuvant letrozole or exemestane) * Histologically documented HR+ breast cancer in either the primary or metastatic setting, as defined by ER or PR ≥ 1%; results from the local lab are acceptable. Eligibility will not be affected by HER2 status. * The most recent treatment prior to enrollment must be one of the following (duration of treatment ≥2 weeks), and must have been adequately tolerated according the treating physician's judgment: * Letrozole * Exemestane * Exemestane + everolimus (everolimus must be discontinued for ≥ 3 weeks prior to starting study treatment) * Letrozole or exemestane in combination with an experimental agent(s) on a clinical trial, provided that the experimental agent(s) is not a PI3K inhibitor or AKT inhibitor (experimental agent(s) must be discontinued for ≥ 3 weeks prior to starting study treatment) * Any number of prior endocrine therapies (including tamoxifen, fulvestrant and/or aromatase inhibitors in either the adjuvant or metastatic setting) and any number of prior chemotherapy regimens. Anti-cancer systemic therapy, such as chemotherapy or biologics or endocrine therapy, other than the AI, must be discontinued for ≥ 3 weeks prior to starting study treatment. * For the dose-finding phase, patients must also have stable disease OR progression of disease on the most recent treatment. For the expansion phase, patients must have progression of disease on the most recent treatment. Progression of disease is defined as new or worsening disease on objective imaging. Progression of disease includes recurrence diagnosed while on adjuvant letrozole or exemestane. * Postmenopausal women, as defined by one of the following (estradiol assay cutoff takes into account that the patient is on aromatase inhibitor therapy): * Age ≥ 55 years and one year or more of amenorrhea * Age \< 55 years and one year or more of amenorrhea, with an estradiol assay within the post-menopausal range * Age \< 55 years with prior hysterectomy but intact ovaries, with an estradiol assay within the post-menopausal range * Surgical menopause with bilateral oophorectomy * Ovarian suppression with a LH-RH agonist, with an estradiol assay within the post-menopausal range at baseline and periodically on-study Measurable or non-measurable disease per RECIST criteria v1.1 * ECOG performance status 0-1 * Adequate organ function, as defined by all of the following: Hematologic parameters: * Absolute neutrophil count (ANC) ≥ 1500/μl (without growth factor support) * Platelets ≥ 100,000/μl (no transfusion allowed within 2 weeks) * Hemoglobin ≥ 9.0 g/dl (may be reached by transfusion) * Liver function: * Serum bilirubin ≤ 1.5 x upper limit of normal (ULN) unless attributable to Gilbert's syndrome * AST ≤ 2.5 x ULN, or ≤ 5 x ULN if liver metastases are present * ALT ≤ 2.5 x ULN, or ≤ 5 x ULN if liver metastases are present Kidney function: * Creatinine ≤ 1.5 ULN * Endocrine function: * Fasting plasma glucose \<140 mg/dl (may be on antiglycemic agents other than insulin). Fasting glucose measurement must be obtained at least 8 hours after the most recent caloric intake. * Ability to swallow oral medication * Willing to discontinue all herbal preparations / medications at least 7 days prior to the first dose of study drug and throughout the study. These include, but not limited to,St. John's wort, Kava, ephedra (ma huang), gingko biloba, dehydroepiandrosterone (DHEA), yohimbe, saw palmetto, and ginseng.

Exclusion criteria

* Pregnant patients or women who are breast-feeding (patients must be postmenopausal, see Section 6.1.9) Patients with central nervous system (CNS) involvement may participate if: * Clinically stable with respect to the CNS tumor at the time of screening and \>4 weeks from prior therapy completion (including radiation and/or surgery) to the start of study treatment * Not receiving steroid therapy * Not receiving enzyme inducing anti-epileptic medications that were started for brain metastases (these include carbamazepine, phenytoin, phenobarbital, primidone, oxcarbazepine, topiramate, and vigabatrin) Prior PI3K inhibitor or AKT inhibitor (patients previously treated with everolimus are eligible, see rationale in Section 3.6) * History of toxicity to the most recent AI (letrozole or exemestane) that warrants cessation of the AI * Patients who have received radiotherapy ≤ 2 weeks prior to starting study treatment * Patients who have undergone major surgery ≤ 4 weeks prior to starting study treatment, who have not recovered from side effects of such procedure * Uncontrolled diabetes (as defined by fasting glucose ≥ 140mg/dL) and/or insulin-dependent diabetes. Fasting glucose measurement must be obtained at least 8 hours after the most recent caloric intake. Patients currently requiring the use of antiglycemic agents (other than insulin) may be enrolled if fasting glucose \<140mg/dL. * Current need for chronic corticosteroid therapy (≥10mg of prednisone daily or an equivalent dose of other corticosteroid), or patients who have received systemic corticosteroids ≤ 2 weeks prior to starting study drug * Current therapeutic anticoagulation with warfarin (or coumarin derivatives) Active infection or serious underlying medical condition that would impair the patient's ability to receive protocol treatment * Clinically significant cardiac disease or impaired cardiac function, such as: * Congestive heart failure requiring treatment (e.g., New York Heart Association Class II, III or IV) Acute coronary syndromes \< 3 months prior to screening (including myocardial infarction, unstable angina, coronary artery bypass graft, coronary angioplasty, or stenting) * Uncontrolled arterial hypertension defined by blood pressure \> 140/100 mm Hg at rest (average of 3 consecutive readings) * History or current evidence of unstable, clinically significant cardiac arrhythmias or patients that require medications with a narrow therapeutic window, atrial fibrillation and/or conduction abnormality, e.g. congenital long QT syndrome, high-Grade/complete AV-blockage * Corrected QT interval (QTc) \> 480 msec on screening ECG Patients who are currently receiving medication with a known risk of prolonging the QT interval or inducing Torsades de Pointes (TdP) and the treatment cannot either be discontinued or switched to a different medication prior to starting study drug treatment (see Section 9.6.3 and Appendix F) * Impaired gastrointestinal function or poorly controlled gastrointestinal disease that may significantly alter the absorption of oral BYL719 (e.g. Crohn's disease, ulcerative colitis, malabsorption syndrome, small bowel resection, uncontrolled nausea or vomiting, or grade ≥ 3 diarrhea of any etiology) based on treating physician assessment * Patients may not have a currently active second malignancy other than non-melanoma skin cancers. Patients are not considered to have a currently active malignancy if they have completed therapy and are considered by their physician to be at less than 30% risk of relapse.

Design outcomes

Primary

MeasureTime frameDescription
Phase II Dose of BYL719/Alpelisib (Arm A and Arm B)28 days (1 Cycle)Participants started BYL719 dose of 300mg daily for cohort 0. Consecutive cohorts were administered increasing or decreasing dose levels of BYL719. All participants within a cohort will be observed for toxicity for one cycle (28 days) prior to entering additional patients.
Phase II Dose of BYL719 (Arm C and Arm D)28 days (1 cycle)Participants started BYL719 dose of 250 daily for cohort 0. Consecutive cohorts were administered increasing or decreasing dose levels of BYL719.

Secondary

MeasureTime frameDescription
Number of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)28 days (1 cycle)Toxicity will be tabulated using the NCI Common Toxicity Criteria (CTCAE), version 4.0. A dose-limiting toxicity (DLT) is defined as an adverse event or abnormal laboratory value assessed as at least possibly related to the study medication, meeting any of the criteria listed in the table below, and occurring during Cycle 1 (≤ 28 days following the first dose of BYL719, including those in which the event started in Cycle 1 and the confirmation of the DLT occurs in a subsequent cycle).
Efficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)2 yearsOverall response rate
Median Time to Treatment Failure/TTFthrough study completion, an average of 3.5 yearsTime to Treatment Failure/TTF defined as the time from on-study date to off-study date for any reason

Countries

United States

Participant flow

Participants by arm

ArmCount
DOSE FINDING PHASE, Arm A, Cohort 0
Period 1: DOSE FINDING PHASE, Arm A, Cohort 0: BYL719 300mg PO, Letrozole 2.5mg PO
4
DOSE FINDING PHASE, Arm A, Cohort -1
Period 2: DOSE FINDING PHASE, Arm A, Cohort -1: BYL719 250 mg PO, Letrozole 2.5mg PO
3
DOSE FINDING PHASE, Arm B, Cohort 0
Period 1: DOSE FINDING PHASE, Arm B, Cohort 0: BYL719 300mg PO, Exemestane 25mg PO
7
Arm D
Arm D : Exemestane 25 mg PO + BYL719 MTD: 350mg PO
10
Dose Finding Phase, Arm C, Cohort 0
Period 1: Dose Finding Phase, Arm C, Cohort 0: Letrozole 2.5mg PO daily & BYL719 250 mg 7days on and 7days off.
6
Dose Finding Phase, Arm C, Cohort 1
Period 2: Dose Finding Phase, Arm C, Cohort 1: Letrozole 2.5mg PO daily & BYL719 300 mg 7days on and 7days off.
6
Dose Finding Phase, Arm D, Cohort 0
Period 1: Dose Finding Phase, Arm D, Cohort 0: Exemestane 25mg PO daily & BYL719 250 mg 5days on and 2days off.
3
Dose Finding Phase, Arm D, Cohort 1
Period 2: Dose Finding Phase, Arm D, Cohort 1: Exemestane 25mg PO daily & BYL719 300 mg 5days on and 2days off.
6
Dose Finding Phase, Arm D, Cohort 2
Period 3: Dose Finding Phase, Arm D, Cohort 2: Exemestane 25mg PO daily & BYL719 350 mg 5days on and 2days off.
7
Total52

Baseline characteristics

CharacteristicDOSE FINDING PHASE, Arm A, Cohort 0TotalDose Finding Phase, Arm D, Cohort 2Dose Finding Phase, Arm D, Cohort 1Dose Finding Phase, Arm D, Cohort 0Dose Finding Phase, Arm C, Cohort 1Dose Finding Phase, Arm C, Cohort 0Arm DDOSE FINDING PHASE, Arm B, Cohort 0DOSE FINDING PHASE, Arm A, Cohort -1
Age, Continuous61 years55 years58 years57 years52 years62 years55 years52 years50 years48 years
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants3 Participants0 Participants0 Participants0 Participants0 Participants1 Participants1 Participants1 Participants0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
4 Participants49 Participants7 Participants6 Participants3 Participants6 Participants5 Participants9 Participants6 Participants3 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants2 Participants0 Participants0 Participants1 Participants0 Participants0 Participants1 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
0 Participants3 Participants0 Participants0 Participants0 Participants0 Participants1 Participants1 Participants1 Participants0 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants7 Participants2 Participants0 Participants0 Participants0 Participants0 Participants3 Participants2 Participants0 Participants
Race (NIH/OMB)
White
4 Participants40 Participants5 Participants6 Participants2 Participants6 Participants5 Participants5 Participants4 Participants3 Participants
Region of Enrollment
United States
4 Participants52 Participants7 Participants6 Participants3 Participants6 Participants6 Participants10 Participants7 Participants3 Participants
Sex: Female, Male
Female
4 Participants52 Participants7 Participants6 Participants3 Participants6 Participants6 Participants10 Participants7 Participants3 Participants
Sex: Female, Male
Male
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
EG004
affected / at risk
EG005
affected / at risk
EG006
affected / at risk
EG007
affected / at risk
EG008
affected / at risk
deaths
Total, all-cause mortality
0 / 40 / 32 / 70 / 101 / 60 / 60 / 30 / 61 / 7
other
Total, other adverse events
4 / 41 / 37 / 710 / 106 / 66 / 60 / 36 / 67 / 7
serious
Total, serious adverse events
1 / 40 / 34 / 72 / 103 / 62 / 60 / 31 / 62 / 7

Outcome results

Primary

Phase II Dose of BYL719/Alpelisib (Arm A and Arm B)

Participants started BYL719 dose of 300mg daily for cohort 0. Consecutive cohorts were administered increasing or decreasing dose levels of BYL719. All participants within a cohort will be observed for toxicity for one cycle (28 days) prior to entering additional patients.

Time frame: 28 days (1 Cycle)

ArmMeasureValue (NUMBER)
Arm A: BYL719 Plus LetrozolePhase II Dose of BYL719/Alpelisib (Arm A and Arm B)250 mg
Arm B: BYL719 Plus ExemestanePhase II Dose of BYL719/Alpelisib (Arm A and Arm B)250 mg
Primary

Phase II Dose of BYL719 (Arm C and Arm D)

Participants started BYL719 dose of 250 daily for cohort 0. Consecutive cohorts were administered increasing or decreasing dose levels of BYL719.

Time frame: 28 days (1 cycle)

ArmMeasureValue (NUMBER)
Arm A: BYL719 Plus LetrozolePhase II Dose of BYL719 (Arm C and Arm D)250 mg
Arm B: BYL719 Plus ExemestanePhase II Dose of BYL719 (Arm C and Arm D)350 mg
Secondary

Efficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)

Overall response rate

Time frame: 2 years

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
Arm A: BYL719 Plus LetrozoleEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Stable Disease (SD)4 Participants
Arm A: BYL719 Plus LetrozoleEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Partial Response (PR)1 Participants
Arm A: BYL719 Plus LetrozoleEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Unevaluable2 Participants
Arm A: BYL719 Plus LetrozoleEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Progression of Disease (POD)0 Participants
Arm A: BYL719 Plus LetrozoleEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Complete Response (CR)0 Participants
Arm B: BYL719 Plus ExemestaneEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Progression of Disease (POD)3 Participants
Arm B: BYL719 Plus ExemestaneEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Complete Response (CR)0 Participants
Arm B: BYL719 Plus ExemestaneEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Unevaluable1 Participants
Arm B: BYL719 Plus ExemestaneEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Partial Response (PR)0 Participants
Arm B: BYL719 Plus ExemestaneEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Stable Disease (SD)3 Participants
Arm C: BYL719 Plus LetrozoleEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Progression of Disease (POD)1 Participants
Arm C: BYL719 Plus LetrozoleEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Partial Response (PR)0 Participants
Arm C: BYL719 Plus LetrozoleEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Stable Disease (SD)6 Participants
Arm C: BYL719 Plus LetrozoleEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Complete Response (CR)0 Participants
Arm C: BYL719 Plus LetrozoleEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Unevaluable5 Participants
Arm DEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Complete Response (CR)1 Participants
Arm DEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Stable Disease (SD)13 Participants
Arm DEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Partial Response (PR)4 Participants
Arm DEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Progression of Disease (POD)5 Participants
Arm DEfficacy of BYL719 (Arm A, Arm B, Arm C and Arm D)Unevaluable3 Participants
Secondary

Median Time to Treatment Failure/TTF

Time to Treatment Failure/TTF defined as the time from on-study date to off-study date for any reason

Time frame: through study completion, an average of 3.5 years

ArmMeasureValue (MEDIAN)
Arm A: BYL719 Plus LetrozoleMedian Time to Treatment Failure/TTF21 weeks
Arm B: BYL719 Plus ExemestaneMedian Time to Treatment Failure/TTF8 weeks
Arm C: BYL719 Plus LetrozoleMedian Time to Treatment Failure/TTF12 weeks
Arm DMedian Time to Treatment Failure/TTF17 weeks
Secondary

Number of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)

Toxicity will be tabulated using the NCI Common Toxicity Criteria (CTCAE), version 4.0. A dose-limiting toxicity (DLT) is defined as an adverse event or abnormal laboratory value assessed as at least possibly related to the study medication, meeting any of the criteria listed in the table below, and occurring during Cycle 1 (≤ 28 days following the first dose of BYL719, including those in which the event started in Cycle 1 and the confirmation of the DLT occurs in a subsequent cycle).

Time frame: 28 days (1 cycle)

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Arm A: BYL719 Plus LetrozoleNumber of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)4 Participants
Arm B: BYL719 Plus ExemestaneNumber of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)3 Participants
Arm C: BYL719 Plus LetrozoleNumber of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)7 Participants
Arm DNumber of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)10 Participants
Dose Finding Phase, Arm C, Cohort 0Number of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)6 Participants
Dose Finding Phase, Arm C, Cohort 1Number of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)6 Participants
Dose Finding Phase, Arm D, Cohort 0Number of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)3 Participants
Dose Finding Phase, Arm D, Cohort 1Number of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)6 Participants
Dose Finding Phase, Arm D, Cohort 2Number of Participants Evaluated for Safety and Tolerability of BYL719 (Arm A, B, C and D)7 Participants

Source: ClinicalTrials.gov · Data processed: Mar 8, 2026