Breast Cancer, Breast Carcinoma, Cancer of Breast, Malignant Tumor of Breast
Conditions
Brief summary
The investigators propose to conduct a study to test an alternative dosing schedule of palbociclib. With the current three-week on and one week off schedule, a significant number of patients develop grade 3 or higher degree of neutropenia and require dose reduction and sometimes discontinuation. This potentially compromises the efficacy of the drug. In addition, as the half-life of palbociclib is 27 hours, 1 week break with the standard 3 weeks on and 1 week off dosing schedule could potentially lead to recovery of Rb phosphorylation during the off week. Hence, the investigators propose a 5 days on and 2 days off schedule each week without any weeks off drug. Although the cumulative doses each 28-day cycle is roughly the same with this schedule compared to conventional dosing, the bone marrow is not exposed to the drug continuously for 21 days and rather gets frequent breaks from therapy. The investigators hypothesize that the 5 days on and 2 days off schedule is more tolerable with less frequent high grade neutropenia and dose interruption/reduction. In addition, this schedule also provides for a more continuous drug delivery to the patient since there is not a week's break in therapy, which could ultimately prove to be more efficacious.
Interventions
DRUGPalbociclib
Palbociclib at a dose of 125 mg should be taken by mouth with food on a 5 days on/2 days off schedule
DRUGLetrozole
Patients who are receiving letrozole will take it daily by mouth, every day of each 28-day cycle, at a dose of 2.5 mg.
DRUGFulvestrant
Patients who are receiving fulvestrant will receive it at a dose of 500 mg as two 5 mL intramuscular injections (one into each buttock) on Days 1 and 15 of Cycle 1 and then on Day 1 of each cycle thereafter.
PROCEDUREOptional research biopsy
Patients may consent to paired tumor biopsies at baseline and time of progression.
DRUGGoserelin
Goserelin is given as a subcutaneous injection every 28 days. It is preferred to be given on Day 1 of each cycle, but it may be administered on any day of the treatment cycle to accommodate its specific Q28-day cycle. It will be given to pre- and peri-menopausal women only.
PROCEDUREResearch blood draw
-Blood will be drawn at the following time points for serum, plasma, cfDNA, and germline DNA (only at baseline): * Baseline * C1D15 * C2D1 * Every 2-3 months thereafter (to coincide with imaging studies) * Time of progression
PROCEDURECirculating tumor cell blood draw
-Baseline, cycle 2 day 1, post 2 or 3 months of therapy (to coincide with first tumor imaging), and progression
PROCEDURETumor biopsy (optional)
-Baseline and progression
Sponsors
Pfizer
Washington University School of Medicine
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Histologically confirmed metastatic ER+ and/or PR+ and HER2- breast cancer who are candidates for palbociclib in combination with either letrozole or fulvestrant per treating physician. * Presence of measurable or non-measurable disease by RECIST 1.1 criteria. * One prior systemic therapy in the metastatic setting is allowed, but patients who have not had any prior systemic therapies in the metastatic setting are also eligible. \*Note: patients who were started on endocrine therapy monotherapy as their 1st line or 2nd line systemic therapy in the metastatic setting for no more than 28 days and without clinical progression prior to the initiation of the study drug therapy are allowed to enroll on the study as their 1st line or 2nd line therapy, respectively. * At least 18 years of age. * Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2 * Normal bone marrow and organ function as defined below: * Absolute neutrophil count ≥ 1,500/mcl * Platelets ≥ 100,000/mcl * Total bilirubin ≤ institutional upper limit of normal (IULN) or total bilirubin ≤ 3.0 x IULN with direct bilirubin within normal range in patients with documented Gilbert's syndrome * AST(SGOT)/ALT(SGPT) ≤ 1.5 x IULN (up to 5 x IULN in patients with liver disease) * Creatinine ≤ IULN OR creatinine clearance ≥ 60 mL/min/1.73 m2 for patients with serum creatinine levels above institutional normal (calculated by Creatinine Clearance Estimate by Cockcroft-Gault Equation) * Pre- or post-menopausal women are allowed. If pre- or peri-menopausal, concurrent ovarian suppression for pre- or peri-menopausal women is required. * Women of childbearing potential must agree to use adequate contraception (hormonal or barrier method of birth control, abstinence) prior to study entry and for the duration of study participation. Should a woman become pregnant or suspect she is pregnant while participating in this study, she must inform her treating physician immediately. * Able to swallow and retain oral medication. * Washout of at least 3 weeks from prior chemotherapy or targeted therapy that induces myelosuppression and recovery of treatment related adverse events to grade 1 or less, with the exception of alopecia, is required prior to the start of palbociclib. * Ability to understand and willingness to sign an Institutional Review Board (IRB) approved written informed consent document (or that of legally authorized representative, if applicable).
Exclusion criteria
* Prior therapy with any CDK inhibitor. * Currently receiving any other investigational agents. * Currently receiving exogenous estrogen replacement (topical vaginal estrogen therapy is allowed). * Known brain metastases. Patients with known brain metastases must be excluded from this clinical trial because of their poor prognosis which could affect the evaluation of all-cycle adverse events. * A history of allergic reactions attributed to compounds of similar chemical or biologic composition to palbociclib or other agents used in the study. * Receiving any medications or substances that are potent inhibitors or inducers of CYP3A isoenzymes within 7 days prior to registration. * Clinically significant history of liver disease. * A condition that would interfere with enteric absorption. * Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, or cardiac arrhythmia. * Pregnant and/or breastfeeding. Women of childbearing potential must have a negative pregnancy test within 7 days of study entry. * Known HIV-positivity on combination antiretroviral therapy because of the potential for pharmacokinetic interactions with palbociclib. In addition, these patients are at increased risk of lethal infections when treated with marrow-suppressive therapy. Appropriate studies will be undertaken in patients receiving combination antiretroviral therapy when indicated.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Rate of Grade 3 or Higher Neutropenia | Through the first 29 days of treatment | * The descriptions and grading scales found in the revised NCI Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 will be utilized for all toxicity reporting. * Grade 3 neutropenia: \<1000-500/mm\^3; \<1.0-0.5 x 10e9/L * Grade 4 neutropenia: \<500/mm\^3; \<0.5 x 10e9/L |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Rate of Grade 3 or Higher Neutropenia | Through 30 day follow-up (estimated to be 25 months) | * The descriptions and grading scales found in the revised NCI Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 will be utilized for all toxicity reporting. * Grade 3 neutropenia: \<1000-500/mm\^3; \<1.0-0.5 x 10e9/L * Grade 4 neutropenia: \<500/mm\^3; \<0.5 x 10e9/L |
| Rate of Palbociclib Dose Reduction | Through the completion of treatment (estimated to be 24 months) | -Percentage of participants who have a palbociclib dose reduction during treatment |
| Rate of Palbociclib Dose Interruption | Through the completion of treatment (estimated to be 24 months) | -Percentage of participants who have a palbociclib dose interruption during treatment |
| Rate of Palbociclib Discontinuation | Through the completion of treatment (estimated to be 24 months) | -Percentage of participants who discontinue palbociclib due to adverse event |
| Kaplan-Meier Estimate of Progression-free Survival (PFS) | 1 year | * PFS will be followed from start of treatment to time of progression or death, whichever occurs first. * Progressive disease: At least a 20% increase in the sum of the diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that is the smallest on study). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. (Note: the appearance of one or more new lesions is also considered progressions). |
| Overall Response Rate (Complete Response + Partial Response) | Time of progression (estimated to be 24 months) | * Complete Response (CR): Disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to \<10 mm, dDisappearance of all non-target lesions and normalization of tumor marker level. All lymph nodes must be non-pathological in size (\<10 mm short axis). * Partial Response (PR): At least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum diameters |
| Clinical Benefit Rate (Complete Response + Partial Response + Stable Disease) for at Least 6 Months) | Time of progression (estimated to be 24 months) | * Complete Response (CR): Disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to \<10 mm, dDisappearance of all non-target lesions and normalization of tumor marker level. All lymph nodes must be non-pathological in size (\<10 mm short axis). * Partial Response (PR): At least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum diameters * Stable Disease (SD): Neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD, taking as reference the smallest sum diameters while on study. |
| Adverse Event Profile of Palbociclib | Through the 30 day follow-up (estimated to be 25 months) | * The descriptions and grading scales found in the revised NCI Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 will be utilized for all toxicity reporting. * Relationship of possible, probably, or definitely related. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Palbociclib + Letrozole or + Fulvestrant * Palbociclib should be taken by mouth with food on a 5 days on/2 days off schedule (meaning: on Days 1-5, 8-12, 15-19, and 22-26 of each 28-day cycle).
* Patients who are receiving letrozole will take it daily by mouth, every day of each 28-day cycle.
* Patients who are receiving fulvestrant will receive it as two intramuscular injections (one into each buttock) on Days 1 and 15 of Cycle 1 and then on Day 1 of each cycle thereafter.
* Goserelin is given as a subcutaneous injection every 28 days. It is preferred to be given on Day 1 of each cycle, but it may be administered on any day of the treatment cycle to accommodate its specific Q28-day cycle. It will be given to pre- or peri-menopausal women only.
* Optional research biopsy at baseline and progression
* Blood for research at baseline, cycle 1 day 15, cycle 2 day 1, every 2-3 months (to coincide with imaging studies), and time of progression | 55 |
| Total | 55 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Overall Study | Deemed not eligible prior to starting palbociclib | 1 |
Baseline characteristics
| Characteristic | Palbociclib + Letrozole or + Fulvestrant |
|---|---|
| Age, Continuous | 61 years |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 55 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants |
| Race (NIH/OMB) Black or African American | 10 Participants |
| Race (NIH/OMB) More than one race | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants |
| Race (NIH/OMB) White | 45 Participants |
| Region of Enrollment United States | 55 participants |
| Sex: Female, Male Female | 55 Participants |
| Sex: Female, Male Male | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 3 / 54 |
| other Total, other adverse events | 54 / 54 |
| serious Total, serious adverse events | 15 / 54 |
Outcome results
Primary
Rate of Grade 3 or Higher Neutropenia
* The descriptions and grading scales found in the revised NCI Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 will be utilized for all toxicity reporting. * Grade 3 neutropenia: \<1000-500/mm\^3; \<1.0-0.5 x 10e9/L * Grade 4 neutropenia: \<500/mm\^3; \<0.5 x 10e9/L
Time frame: Through the first 29 days of treatment
Population: The following participants were not evaluable for this outcome measure: 4 participants did not take palbociclib dose as per protocol and were without dose-limiting toxicity; 2 participants withdrew in cycle 1, and 1 participant went off treatment in cycle 1 due to adverse events unrelated to the study.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Palbociclib + Letrozole or + Fulvestrant | Rate of Grade 3 or Higher Neutropenia | 10 Participants |
Secondary
Adverse Event Profile of Palbociclib
* The descriptions and grading scales found in the revised NCI Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 will be utilized for all toxicity reporting. * Relationship of possible, probably, or definitely related.
Time frame: Through the 30 day follow-up (estimated to be 25 months)
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 rash maculo-papular | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 anemia | 31 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 anemia | 4 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 blurred vision | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1/2 constipation | 5 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 diarrhea | 8 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 dyspepsia | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 gastric ulcer | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 mucositis oral | 11 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 nausea | 16 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 oral dysesthesia | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 vomiting | 7 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 chills | 3 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 fatigue | 22 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 fever | 3 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 diverticulitis | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 sepsis | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 urinary tract infection | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 bruising | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 radiation recall reaction (dermatologic) | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 alanine aminotransferase increased | 4 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 alanine aminotransferase increased | 2 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 alkaline phosphatase increased | 4 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 aspartate aminotransferase increased | 4 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 aspartate aminotransferase increased | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 blood bilirubin increased | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 creatinine increased | 2 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 hemoglobin increased | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 lymphocyte count decreased | 23 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 lymphocyte count decreased | 13 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 neutrophil count decreased | 22 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 neutrophil count decreased | 24 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 platelet count decreased | 21 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 platelet count decreased | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 weight loss | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 weight loss | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 white blood cell decreased | 26 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 white blood cell decreased | 26 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 anorexia | 4 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 hyperglycemia | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 hypermagnesemia | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 hypoalbuminemia | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 hypocalcemia | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 hypokalemia | 2 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 hyponatremia | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 arthralgia | 6 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 arthritis | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 back pain | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 bone pain | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 leg stiffness | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 muscle cramps | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 myalgia | 3 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 neck pain | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 osteonecrosis of jaw | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 pain in extremity | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 dizziness | 4 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 dizziness | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 dysgeusia | 5 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 headache | 2 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 spasticity | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 depression | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 insomnia | 3 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 mood swings | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 breast pain | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 vaginal dryness | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 epistaxis | 2 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 sore throat | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 voice alteration | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 alopecia | 19 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 brittle nails | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 dry skin | 2 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 hyperhidrosis | 3 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 itchy skin | 3 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 nail loss | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 oral fissure | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 rash acneiform | 1 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 hot flashes | 12 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 1-2 hypertension | 2 Participants |
| Palbociclib + Letrozole or + Fulvestrant | Adverse Event Profile of Palbociclib | Grade 3-4 thromboembolic event | 1 Participants |
Secondary
Clinical Benefit Rate (Complete Response + Partial Response + Stable Disease) for at Least 6 Months)
* Complete Response (CR): Disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to \<10 mm, dDisappearance of all non-target lesions and normalization of tumor marker level. All lymph nodes must be non-pathological in size (\<10 mm short axis). * Partial Response (PR): At least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum diameters * Stable Disease (SD): Neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD, taking as reference the smallest sum diameters while on study.
Time frame: Time of progression (estimated to be 24 months)
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Palbociclib + Letrozole or + Fulvestrant | Clinical Benefit Rate (Complete Response + Partial Response + Stable Disease) for at Least 6 Months) | 45 Participants |
Secondary
Kaplan-Meier Estimate of Progression-free Survival (PFS)
* PFS will be followed from start of treatment to time of progression or death, whichever occurs first. * Progressive disease: At least a 20% increase in the sum of the diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that is the smallest on study). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. (Note: the appearance of one or more new lesions is also considered progressions).
Time frame: 1 year
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Palbociclib + Letrozole or + Fulvestrant | Kaplan-Meier Estimate of Progression-free Survival (PFS) | 67.911 percentage of participants-Kaplan Meier |
Secondary
Overall Response Rate (Complete Response + Partial Response)
* Complete Response (CR): Disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to \<10 mm, dDisappearance of all non-target lesions and normalization of tumor marker level. All lymph nodes must be non-pathological in size (\<10 mm short axis). * Partial Response (PR): At least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum diameters
Time frame: Time of progression (estimated to be 24 months)
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Palbociclib + Letrozole or + Fulvestrant | Overall Response Rate (Complete Response + Partial Response) | 18 Participants |
Secondary
Rate of Grade 3 or Higher Neutropenia
* The descriptions and grading scales found in the revised NCI Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 will be utilized for all toxicity reporting. * Grade 3 neutropenia: \<1000-500/mm\^3; \<1.0-0.5 x 10e9/L * Grade 4 neutropenia: \<500/mm\^3; \<0.5 x 10e9/L
Time frame: Through 30 day follow-up (estimated to be 25 months)
Population: The following participants were not evaluable for this outcome measure: 4 participants did not take palbociclib dose as per protocol and were without dose-limiting toxicity; 2 participants withdrew in cycle 1, and 1 participant went off treatment in cycle 1 due to adverse events unrelated to the study.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Palbociclib + Letrozole or + Fulvestrant | Rate of Grade 3 or Higher Neutropenia | 23 Participants |
Secondary
Rate of Palbociclib Discontinuation
-Percentage of participants who discontinue palbociclib due to adverse event
Time frame: Through the completion of treatment (estimated to be 24 months)
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Palbociclib + Letrozole or + Fulvestrant | Rate of Palbociclib Discontinuation | 2 Participants |
Secondary
Rate of Palbociclib Dose Interruption
-Percentage of participants who have a palbociclib dose interruption during treatment
Time frame: Through the completion of treatment (estimated to be 24 months)
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Palbociclib + Letrozole or + Fulvestrant | Rate of Palbociclib Dose Interruption | 39 Participants |
Secondary
Rate of Palbociclib Dose Reduction
-Percentage of participants who have a palbociclib dose reduction during treatment
Time frame: Through the completion of treatment (estimated to be 24 months)
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Palbociclib + Letrozole or + Fulvestrant | Rate of Palbociclib Dose Reduction | 13 Participants |