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CLINICAL PHARMACOLOGY Mechanism Of Action Palbociclib is an inhibitor of cyclin-dependent kinases (CDK) 4 and 6. Cyclin D1 and CDK4/6 are downstream of signaling pathways which lead to cellular proliferation. In vitro, palbociclib reduced cellular proliferation of estrogen receptor (ER)-positive breast cancer cell lines by blocking progression of the cell from G1 into S phase of the cell cycle. Treatment of breast cancer cell lines with the combination of palbociclib and antiestrogens leads to decreased retinoblastoma (Rb) protein phosphorylation resulting in reduced E2F expression and signaling, and increased growth arrest compared to treatment with each drug alone. In vitro treatment of ER-positive breast cancer cell lines with the combination of palbociclib and antiestrogens led to increased cell senescence compared to each drug alone, which was sustained for up to 6 days following palbociclib removal and was greater if antiestrogen treatment was continued. In vivo studies using a patient-derived ER-positive breast cancer xenograft model demonstrated that the combination of palbociclib and letrozole increased the inhibition of Rb phosphorylation, downstream signaling, and tumor growth compared to each drug alone. Human bone marrow mononuclear cells treated with palbociclib in the presence or absence of an anti-estrogen in vitro did not become senescent and resumed proliferation following palbociclib withdrawal. Pharmacodynamics Cardiac Electrophysiology The effect of palbociclib on the QT interval corrected for heart rate (QTc) was evaluated using time-matched electrocardiograms (ECGs) evaluating the change from baseline and corresponding pharmacokinetic data in 77 patients with breast cancer. Palbociclib had no large effect on QTc (i.e. > 20 ms) at 125 mg once daily (Schedule 3/1). Pharmacokinetics The pharmacokinetics (PK) of palbociclib were characterized in patients with solid tumors including advanced breast cancer and in healthy subjects. Absorption The mean maximum observed concentration (Cmax) of palbociclib is generally observed between 6 to 12 hours (time to reach maximum concentration, Tmax) following oral administration. The mean absolute bioavailability of IBRANCE after an oral 125 mg dose is 46%. In the dosing range of 25 mg to 225 mg, the AUC and Cmax increased proportionally with dose in general. Steady state was achieved within 8 days following repeated once daily dosing. With repeated once daily administration, palbociclib accumulated with a median accumulation ratio of 2.4 (range 1.5 to 4.2). Food effect Palbociclib absorption and exposure were very low in approximately 13% of the population under the fasted condition. Food intake increased the palbociclib exposure in this small subset of the population, but did not alter palbociclib exposure in the rest of the population to a clinically relevant extent. Therefore, food intake reduced the intersubject variability of palbociclib exposure, which supports administration of IBRANCE with food. Compared to IBRANCE given under overnight fasted conditions, the population average area under the concentration-time curve from zero to infinity (AUCINF) and Cmax of palbociclib increased by 21% and 38%, respectively, when given with high-fat, high-calorie food (approximately 800 to 1000 calories with 150, 250, and 500 to 600 calories from protein, carbohydrate, and fat, respectively), by 12% and 27%, respectively, when given with low-fat, low-calorie food (approximately 400 to 500 calories with 120, 250, and 28 to 35 calories from protein, carbohydrate, and fat, respectively), and by 13% and 24%, respectively, when moderate-fat, standard calorie food (approximately 500 to 700 calories with 75 to 105, 250 to 350 and 175 to 245 calories from protein, carbohydrate, and fat, respectively) was given 1 hour before and 2 hours after IBRANCE dosing. Distribution Binding of palbociclib to human plasma proteins in vitro was approximately 85%, with no concentration dependence over the concentration range of 500 ng/mL to 5000 ng/mL. The geometric mean apparent volume of distribution (Vz/F) was 2583 L with a coefficient of variation (CV) of 26%. Metabolism In vitro and in vivo studies indicated that palbociclib undergoes hepatic metabolism in humans. Following oral administration of a single 125 mg dose of [14C]palbociclib to humans, the primary metabolic pathways for palbociclib involved oxidation and sulfonation, with acylation and glucuronidation contributing as minor pathways. Palbociclib was the major circulating drug-derived entity in plasma (23%). The major circulating metabolite was a glucuronide conjugate of palbociclib, although it only represented 1.5% of the administered dose in the excreta. Palbociclib was extensively metabolized with unchanged drug accounting for 2.3% and 6.9% of radioactivity in feces and urine, respectively. In feces, the sulfamic acid conjugate of palbociclib was the major drug-related component, accounting for 26% of the administered dose. In vitro studies with human hepatocytes, liver cytosolic and S9 fractions, and recombinant SULT enzymes indicated that CYP3A and SULT2A1 are mainly involved in the metabolism of palbociclib. Elimination The geometric mean apparent oral clearance (CL/F) of palbociclib was 63.1 L/hr (29% CV), and the mean (± standard deviation) plasma elimination half-life was 29 (±5) hours in patients with advanced breast cancer. In 6 healthy male subjects given a single oral dose of [14C]palbociclib, a median of 91.6% of the total administered radioactive dose was recovered in 15 days; feces (74.1% of dose) was the major route of excretion, with 17.5% of the dose recovered in urine. The majority of the material was excreted as metabolites. Age, Gender, And Body Weight Based on a population pharmacokinetic analysis in 183 patients with cancer (50 male and 133 female patients, age range from 22 to 89 years, and body weight range from 37.9 to 123 kg), gender had no effect on the exposure of palbociclib, and age and body weight had no clinically important effect on the exposure of palbociclib. Pediatric Population Pharmacokinetics of IBRANCE have not been evaluated in patients <18 years of age. Drug Interactions In vitro data indicate that CYP3A and SULT enzyme SULT2A1 are mainly involved in the metabolism of palbociclib. Palbociclib is a weak time-dependent inhibitor of CYP3A following daily 125 mg dosing to steady state in humans. In vitro, palbociclib is not an inhibitor of CYP1A2, 2A6, 2B6, 2C8, 2C9, 2C19, and 2D6, and is not an inducer of CYP1A2, 2B6, 2C8, and 3A4 at clinically relevant concentrations. CYP3A Inhibitors Data from a drug interaction trial in healthy subjects (N=12) indicate that coadministration of multiple 200 mg daily doses of itraconazole with a single 125 mg IBRANCE dose increased palbociclib AUCINF and the Cmax by approximately 87% and 34%, respectively, relative to a single 125 mg IBRANCE dose given alone [see DRUG INTERACTIONS]. CYP3A Inducers Data from a drug interaction trial in healthy subjects (N=15) indicate that coadministration of multiple 600 mg daily doses of rifampin, a strong CYP3A inducer, with a single 125 mg IBRANCE dose decreased palbociclib AUCINF and Cmax by 85% and 70%, respectively, relative to a single 125 mg IBRANCE dose given alone. Data from a drug interaction trial in healthy subjects (N=14) indicate that coadministration of multiple 400 mg daily doses of modafinil, a moderate CYP3A inducer, with a single 125 mg IBRANCE dose decreased palbociclib AUCINF and Cmax by 32% and 11%, respectively, relative to a single 125 mg IBRANCE dose given alone [see DRUG INTERACTIONS]. CYP3A Substrates Palbociclib is a weak time-dependent inhibitor of CYP3A following daily 125 mg dosing to steady state in humans. In a drug interaction trial in healthy subjects (N=26), coadministration of midazolam with multiple doses of IBRANCE increased the midazolam AUCINF and the Cmax values by 61% and 37%, respectively, as compared to administration of midazolam alone [see DRUG INTERACTIONS]. Gastric pH Elevating Medications In a drug interaction trial in healthy subjects, coadministration of a single 125 mg dose of IBRANCE with multiple doses of the proton pump inhibitor (PPI) rabeprazole under fed conditions decreased palbociclib Cmax by 41%, but had limited impact on AUCINF (13% decrease), when compared to a single dose of IBRANCE administered alone. Given the reduced effect on gastric pH of H2-receptor antagonists and local antacids compared to PPIs, the effect of these classes of acid-reducing agents on palbociclib exposure under fed conditions is expected to be minimal. Under fed conditions there is no clinically relevant effect of PPIs, H2-receptor antagonists, or local antacids on palbociclib exposure. In another healthy subject study, coadministration of a single dose of IBRANCE with multiple doses of the PPI rabeprazole under fasted conditions decreased palbociclib AUCINF and Cmax by 62% and 80%, respectively, when compared to a single dose of IBRANCE administered alone. Letrozole Data from a clinical trial in patients with breast cancer showed that there was no drug interaction between palbociclib and letrozole when the 2 drugs were coadministered. Fulvestrant Data from a clinical trial in patients with breast cancer showed that there was no clinically relevant drug interaction between palbociclib and fulvestrant when the 2 drugs were coadministered. Goserelin Data from a clinical trial in patients with breast cancer showed that there was no clinically relevant drug interaction between palbociclib and goserelin when the 2 drugs were coadministered. Anastrozole Or exemestane No clinical data are available to evaluate drug interactions between anastrozole or exemestane and palbociclib. A clinically significant drug interaction between anastrozole or exemestane and palbociclib is not expected based on analyses of the effects of anastrozole, exemestane and palbociclib on or by metabolic pathways or transporter systems. Effect Of Palbociclib On Transporters In vitro evaluations indicated that palbociclib has a low potential to inhibit the activities of drug transporters P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), organic anion transporter (OAT)1, OAT3, organic cation transporter (OCT)2, and organic anion transporting polypeptide (OATP)1B1, OATP1B3 at clinically relevant concentrations. Effect Of Transporters On Palbociclib Based on in vitro data, P-gp and BCRP mediated transport are unlikely to affect the extent of oral absorption of palbociclib at therapeutic doses. Clinical Studies Study 1: IBRANCE Plus Letrozole Patients With ER-positive, HER2-Negative Advanced Or Metastatic Breast Cancer For Initial Endocrine Based Therapy Study 1 (PALOMA-2) was an international, randomized, double-blind, parallel-group, multicenter study of IBRANCE plus letrozole versus placebo plus letrozole conducted in postmenopausal women with ER-positive, HER2-negative advanced breast cancer who had not received previous systemic treatment for their advanced disease. A total of 666 patients were randomized 2:1 to IBRANCE plus letrozole or placebo plus letrozole. Randomization was stratified by disease site (visceral versus non-visceral), disease-free interval (de novo metastatic versus ≤12 months from the end of adjuvant treatment to disease recurrence versus >12 months from the end of adjuvant treatment to disease recurrence), and nature of prior (neo)adjuvant anticancer therapies (prior hormonal therapies versus no prior hormonal therapy). IBRANCE was given orally at a dose of 125 mg daily for 21 consecutive days followed by 7 days off treatment. Patients received study treatment until objective disease progression, symptomatic deterioration, unacceptable toxicity, death, or withdrawal of consent, whichever occurred first. The major efficacy outcome of the study was investigator-assessed progression-free survival (PFS) evaluated according to Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST). Patients enrolled in this study had a median age of 62 years (range 28 to 89). The majority of patients were White (78%), and most patients had an Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 or 1 (98%). Forty-eight percent of patients had received chemotherapy and 56% had received antihormonal therapy in the neoadjuvant or adjuvant setting prior to their diagnosis of advanced breast cancer. Thirty-seven percent of patients had no prior systemic therapy in the neoadjuvant or adjuvant setting. The majority of patients (97%) had metastatic disease. Twenty-three percent of patients had bone only disease, and 49% of patients had visceral disease. Major efficacy results from Study 1 are summarized in Table 8 and Figure 1. Consistent results were observed across patient subgroups of disease-free interval (DFI), disease site, and prior therapy. The treatment effect of the combination on PFS was also supported by an independent review of radiographs. The overall survival (OS) data were not mature at the time of the final PFS analysis (20% of patients had died). Patients will continue to be followed for the final analysis. Table 8. Efficacy Results – Study 1 (Investigator Assessment, Intent-to-Treat Population) IBRANCE plus Letrozole Placebo plus Letrozole Progression-free survival for ITT N=444 N=222 Number of PFS events (%) 194 (43.7) 137 (61.7) Median progression-free survival (months, 95% CI) 24.8 (22.1, NE) 14.5 (12.9, 17.1) Hazard ratio (95% CI) and p-value 0.576 (0.463, 0.718), p<0.0001 Objective Response for patients with measurable disease N=338 N=171 Objective response rate* (%, 95% CI) 55.3 (49.9, 60.7) 44.4 (36.9, 52.2) *Response based on confirmed responses CI=confidence interval; ITT=Intent-to-Treat; N=number of patients; NE=not estimable. Figure 1. Kaplan-Meier Plot of Progression-Free Survival – Study 1 (Investigator Assessment, Intent-to-Treat Population) Study 2: IBRANCE Plus Fulvestrant Patients With HR-positive, HER2-Negative Advanced Or Metastatic Breast Cancer Who Have Had Disease Progression On Or After Prior Adjuvant Or Metastatic Endocrine Therapy Study 2 (PALOMA-3) was an international, randomized, double-blind, parallel group, multicenter study of IBRANCE plus fulvestrant versus placebo plus fulvestrant conducted in women with HR-positive, HER2-negative advanced breast cancer, regardless of their menopausal status, whose disease progressed on or after prior endocrine therapy. A total of 521 pre/postmenopausal women were randomized 2:1 to IBRANCE plus fulvestrant or placebo plus fulvestrant and stratified by documented sensitivity to prior hormonal therapy, menopausal status at study entry (pre/peri versus postmenopausal), and presence of visceral metastases. IBRANCE was given orally at a dose of 125 mg daily for 21 consecutive days followed by 7 days off treatment. Pre/perimenopausal women were enrolled in the study and received the LHRH agonist goserelin for at least 4 weeks prior to and for the duration of Study 2. Patients continued to receive assigned treatment until objective disease progression, symptomatic deterioration, unacceptable toxicity, death, or withdrawal of consent, whichever occurred first. The major efficacy outcome of the study was investigator-assessed PFS evaluated according to RECIST 1.1. Patients enrolled in this study had a median age of 57 years (range 29 to 88). The majority of patients on study were White (74%), all patients had an ECOG PS of 0 or 1, and 80% were postmenopausal. All patients had received prior systemic therapy, and 75% of patients had received a previous chemotherapy regimen. Twenty-five percent of patients had received no prior therapy in the metastatic disease setting, 60% had visceral metastases, and 23% had bone only disease. The results from the investigator-assessed PFS from Study 2 are summarized in Table 9 and Figure 2. Consistent results were observed across patient subgroups of disease site, sensitivity to prior hormonal therapy and menopausal status. The overall survival (OS) data were not mature at the time of the final PFS analysis (11% of patients had died). Patients will continue to be followed for the final analysis. Table 9. Efficacy Results – Study 2 (Investigator Assessment, Intent-to-Treat Population) IBRANCE plus Fulvestrant Placebo plus Fulvestrant Progression-free survival for ITT N=347 N=174 Number of PFS events (%) 145 (41.8%) 114 (65.5%) Median progression-free survival (months, 95% CI) 9.5 (9.2, 11.0) 4.6 (3.5, 5.6) Hazard ratio (95% CI) and p-value 0.461 (0.360, 0.591), p < 0.0001 Objective Response for patients with measurable disease N=267 N=138 Objective response rate* (%, 95% CI) 24.6 (19.6, 30.2) 10.9 (6.2, 17.3) *Response based on confirmed responses CI=confidence interval; ITT=Intent-to-Treat; N=number of patients; NE=not estimable. Figure 2. Kaplan-Meier Plot of Progression-Free Survival (Investigator Assessment, Intent-to-Treat Population) – Study 2

Find Lowest Prices on IBRANCE® (palbociclib) Capsules DESCRIPTION IBRANCE capsules for oral administration contain 125 mg, 100 mg, or 75 mg of palbociclib, a kinase inhibitor. The molecular formula for palbociclib is C24H29N7O2. The molecular weight is 447.54 daltons. The chemical name is 6-acetyl-8-cyclopentyl-5-methyl-2-{[5-(piperazin-1-yl)pyridin-2yl]amino}pyrido[2,3-d]pyrimidin-7(8H)-one, and its structural formula is: Palbociclib is a yellow to orange powder with pKa of 7.4 (the secondary piperazine nitrogen) and 3.9 (the pyridine nitrogen). At or below pH 4, palbociclib behaves as a high-solubility compound. Above pH 4, the solubility of the drug substance reduces significantly. Inactive Ingredients Microcrystalline cellulose, lactose monohydrate, sodium starch glycolate, colloidal silicon dioxide, magnesium stearate, and hard gelatin capsule shells. The light orange, light orange/caramel, and caramel opaque capsule shells contain gelatin, red iron oxide, yellow iron oxide, and titanium dioxide; the printing ink contains shellac, titanium dioxide, ammonium hydroxide, propylene glycol, and simethicone.

INDICATIONS IBRANCE is indicated for the treatment of HR-positive, HER2-negative advanced or metastatic breast cancer in combination with: an aromatase inhibitor as initial endocrine based therapy in postmenopausal women; or fulvestrant in women with disease progression following endocrine therapy. DOSAGE AND ADMINISTRATION Recommended Dose And Schedule The recommended dose of IBRANCE is a 125 mg capsule taken orally once daily for 21 consecutive days followed by 7 days off treatment to comprise a complete cycle of 28 days. IBRANCE should be taken with food [see CLINICAL PHARMACOLOGY]. Administer the recommended dose of an aromatase inhibitor when given with IBRANCE. Please refer to the Full Prescribing Information for the aromatase inhibitor being used. When given with IBRANCE, the recommended dose of fulvestrant is 500 mg administered on Days 1, 15, 29, and once monthly thereafter. Please refer to the Full Prescribing Information of fulvestrant. Patients should be encouraged to take their dose of IBRANCE at approximately the same time each day. If the patient vomits or misses a dose, an additional dose should not be taken. The next prescribed dose should be taken at the usual time. IBRANCE capsules should be swallowed whole (do not chew, crush, or open them prior to swallowing). Capsules should not be ingested if they are broken, cracked, or otherwise not intact. Pre/perimenopausal women treated with the combination IBRANCE plus fulvestrant therapy should be treated with luteinizing hormone-releasing hormone (LHRH) agonists according to current clinical practice standards. Dose Modification The recommended dose modifications for adverse reactions are listed in Tables 1, 2, and 3. Table 1. Recommended Dose Modification for Adverse Reactions Dose Level Dose Recommended starting dose 125 mg/day First dose reduction 100 mg/day Second dose reduction 75 mg/day* *If further dose reduction below 75 mg/day is required, discontinue. Table 2. Dose Modification and Management – Hematologic Toxicitiesa Monitor complete blood counts prior to the start of IBRANCE therapy and at the beginning of each cycle, as well as on Day 15 of the first 2 cycles, and as clinically indicated. For patients who experience a maximum of Grade 1 or 2 neutropenia in the first 6 cycles, monitor complete blood counts for subsequent cycles every 3 months, prior to the beginning of a cycle and as clinically indicated. CTCAE Grade Dose Modifications Grade 1 or 2 No dose adjustment is required. Grade 3 Day 1 of cycle: Withhold IBRANCE, repeat complete blood count monitoring within 1 week. When recovered to Grade .2, start the next cycle at the same dose. Day 15 of first 2 cycles: If Grade 3 on Day 15, continue IBRANCE at current dose to complete cycle and repeat complete blood count on Day 22. If Grade 4 on Day 22, see Grade 4 dose modification guidelines below. Consider dose reduction in cases of prolonged (>1 week) recovery from Grade 3 neutropenia or recurrent Grade 3 neutropenia on Day 1 of subsequent cycles. Grade 3 neutropeniab with fever ≥38.5 °C and/or infection At any time: Withhold IBRANCE until recovery to Grade ≤2. Resume at the next lower dose. Grade 4 At any time: Withhold IBRANCE until recovery to Grade ≤2. Resume at the next lower dose. Grading according to CTCAE 4.0. CTCAE=Common Terminology Criteria for Adverse Events; LLN=lower limit of normal. a Table applies to all hematologic adverse reactions except lymphopenia (unless associated with clinical events, e.g., opportunistic infections). b Absolute neutrophil count (ANC): Grade 1: ANC < LLN -1500/mm3; Grade 2: ANC 1000 -<1500/mm3; Grade 3: ANC 500 -<1000/mm3; Grade 4: ANC <500/mm3 . Table 3. Dose Modification and Management – Non-Hematologic Toxicities CTCAE Grade Dose Modifications Grade 1 or 2 No dose adjustment is required. Grade ≥3 non-hematologic toxicity (if persisting despite optimal medical treatment) Withhold until symptoms resolve to: Grade ≤1; Grade ≤2 (if not considered a safety risk for the patient) Resume at the next lower dose. Grading according to CTCAE 4.0. CTCAE=Common Terminology Criteria for Adverse Events. Refer to the Full Prescribing Information for coadministered endocrine therapy dose adjustment guidelines in the event of toxicity and other relevant safety information or contraindications. Dose Modifications For Use With Strong CYP3A Inhibitors Avoid concomitant use of strong CYP3A inhibitors and consider an alternative concomitant medication with no or minimal CYP3A inhibition. If patients must be coadministered a strong CYP3A inhibitor, reduce the IBRANCE dose to 75 mg once daily. If the strong inhibitor is discontinued, increase the IBRANCE dose (after 3 to 5 half-lives of the inhibitor) to the dose used prior to the initiation of the strong CYP3A inhibitor [see DRUG INTERACTIONS and CLINICAL PHARMACOLOGY]. HOW SUPPLIED Dosage Forms And Strengths 125 mg capsules: opaque, hard gelatin capsules, size 0, with caramel cap and body, printed with white ink “Pfizer” on the cap, “PBC 125” on the body. 100 mg capsules: opaque, hard gelatin capsules, size 1, with caramel cap and light orange body, printed with white ink “Pfizer” on the cap, “PBC 100” on the body. 75 mg capsules: opaque, hard gelatin capsules, size 2, with light orange cap and body, printed with white ink “Pfizer” on the cap, “PBC 75” on the body. Storage And Handling IBRANCE is supplied in the following strengths and package configurations: IBRANCE Capsules Package Configuration Capsule Strength (mg) NDC Capsule Description Bottles of 21 capsules 125 NDC 0069-0189-21 opaque, hard gelatin capsules, size 0, with caramel cap and body, printed with white ink “Pfizer” on the cap,“PBC 125” on the body Bottles of 21 capsules 100 NDC 0069-0188-21 opaque, hard gelatin capsules, size 1, with caramel cap and light orange body, printed with white ink “Pfizer” on the cap, “PBC 100” on the body Bottles of 21 capsules 75 NDC 0069-0187-21 opaque, hard gelatin capsules, size 2, with light orange cap and body, printed with white ink “Pfizer” on the cap, “PBC 75” on the body Store at 20 °C to 25 °C (68 °F to 77 °F); excursions permitted between 15 °C to 30 °C (59 °F to 86 °F) [see USP Controlled Room Temperature]. Distributed by: Pfizer labs, Division pfizer Inc, NY 10017. Revised: Mar 2017.

PATIENT INFORMATION IBRANCE® (EYE-brans) (palbociclib) Capsules What is the most important information I should know about IBRANCE? IBRANCE may cause serious side effects, including: Low white blood cell counts (neutropenia). Low white blood cell counts are very common when taking IBRANCE and may cause serious infections that can lead to death. Your healthcare provider should check your white blood cell counts before and during treatment. If you develop low white blood cell counts during treatment with IBRANCE, your healthcare provider may stop your treatment, decrease your dose, or may tell you to wait to begin your treatment cycle. Tell your healthcare provider right away if you have signs and symptoms of low white blood cell counts or infections such as fever and chills. See “What are the possible side effects of IBRANCE?” for more information about side effects. What is IBRANCE? IBRANCE is a prescription medicine used to treat hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer that has spread to other parts of the body (metastatic) in combination with: an aromatase inhibitor as the first hormonal based therapy in women who have gone through menopause, or fulvestrant in women with disease progression following hormonal therapy. It is not known if IBRANCE is safe and effective in children. What should I tell my healthcare provider before taking IBRANCE? Before you take IBRANCE, tell your healthcare provider if you: have fever, chills, or any other signs or symptoms of infection. have liver or kidney problems. have any other medical conditions. are pregnant, or plan to become pregnant. IBRANCE can harm your unborn baby. Females who are able to become pregnant and who take IBRANCE should use effective birth control during treatment and for at least 3 weeks after stopping IBRANCE. Males who are taking IBRANCE, with female partners who can become pregnant should use effective birth control during treatment with IBRANCE for 3 months after the final dose of IBRANCE. Talk to your healthcare provider about birth control methods that may be right for you during this time. If you become pregnant or think you are pregnant, tell your healthcare provider right away. are breastfeeding or plan to breastfeed. It is not known if IBRANCE passes into your breast milk. You and your healthcare provider should decide if you will take IBRANCE or breastfeed. You should not do both. Tell your healthcare provider about all of the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. IBRANCE and other medicines may affect each other causing side effects. Know the medicines you take. Keep a list of them to show your healthcare provider or pharmacist when you get a new medicine. How should I take IBRANCE? Take IBRANCE exactly as your healthcare provider tells you. Take IBRANCE with food. Swallow IBRANCE capsules whole. Do not chew, crush or open IBRANCE capsules before swallowing them. Do not take any IBRANCE capsules that are broken, cracked, or that look damaged. Avoid grapefruit and grapefruit products during treatment with IBRANCE. Grapefruit may increase the amount of IBRANCE in your blood. Do not change your dose or stop taking IBRANCE unless your healthcare provider tells you. If you miss a dose of IBRANCE or vomit after taking a dose of IBRANCE, do not take another dose on that day. Take your next dose at your regular time. • If you take too much IBRANCE, call your healthcare provider right away or go to the nearest hospital emergency room. What are the possible side effects of IBRANCE? IBRANCE may cause serious side effects. See “What is the most important information I should know about IBRANCE?” Common side effects of IBRANCE when used with either letrozole or fulvestrant include: Low red blood cell counts and low platelet counts are common with IBRANCE. Call your healthcare provider right away if you develop any of these symptoms during treatment: dizziness bleeding or bruising more easily shortness of breath weakness nosebleeds infections (see “What is the most important information I should know about IBRANCE?”) tiredness diarrhea hair thinning or hair loss vomiting nausea sore mouth abnormalities in liver blood tests rash loss of appetite IBRANCE may cause fertility problems in males. This may affect your ability to father a child. Talk to your healthcare provider if this is a concern for you. Tell your healthcare provider if you have any side effect that bothers you or that does not go away. These are not all of the possible side effects of IBRANCE. For more information, ask your healthcare provider or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. How should I store IBRANCE? Store IBRANCE at 68 °F to 77 °F (20 °C to 25 °C). Keep IBRANCE and all medicines out of the reach of children. General information about the safe and effective use of IBRANCE Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use IBRANCE for a condition for which it was not prescribed. Do not give IBRANCE to other people, even if they have the same symptoms you have. It may harm them. If you would like more information, talk with your healthcare provider. You can ask your pharmacist or healthcare provider for more information about IBRANCE that is written for health professionals. For more information, go to www.IBRANCE.com or call 1-800-438-1985. What are the ingredients in IBRANCE? Active ingredient: palbociclib Inactive ingredients: Microcrystalline cellulose, lactose monohydrate, sodium starch glycolate, colloidal silicon dioxide, magnesium stearate, and hard gelatin capsule shells. Light orange, light orange/caramel and caramel opaque capsule shells contain: gelatin, red iron oxide, yellow iron oxide, and titanium dioxide. Printing ink contains: shellac, titanium dioxide, ammonium hydroxide, propylene glycol, and simethicone. LAB-0724-2.1

OVERDOSE There is no known antidote for IBRANCE. The treatment of overdose of IBRANCE should consist of general supportive measures. CONTRAINDICATIONS None.

SIDE EFFECTS The following topic is described below and elsewhere in the labeling: Neutropenia [see WARNINGS AND PRECAUTIONS] Clinical Studies Experience Because clinical trials are conducted under varying conditions, the adverse reaction rates observed cannot be directly compared to rates in other trials and may not reflect the rates observed in clinical practice. Study 1: IBRANCE Plus Letrozole Patients With Estrogen Receptor (ER)-Positive, HER2-Negative Advanced Or Metastatic Breast Cancer For Initial Endocrine Based Therapy The safety of IBRANCE (125 mg/day) plus letrozole (2.5 mg/day) versus placebo plus letrozole was evaluated in Study 1 (PALOMA-2). The data described below reflect exposure to IBRANCE in 444 out of 666 patients with ER-positive, HER2-negative advanced breast cancer who received at least 1 dose of IBRANCE plus letrozole in Study 1. The median duration of treatment for IBRANCE plus letrozole was 19.8 months while the median duration of treatment for placebo plus letrozole arm was 13.8 months. Dose reductions due to an adverse reaction of any grade occurred in 36% of patients receiving IBRANCE plus letrozole. No dose reduction was allowed for letrozole in Study 1. Permanent discontinuation associated with an adverse reaction occurred in 43 of 444 (9.7%) patients receiving IBRANCE plus letrozole and in 13 of 222 (5.9%) patients receiving placebo plus letrozole. Adverse reactions leading to permanent discontinuation for patients receiving IBRANCE plus letrozole included neutropenia (1.1%) and alanine aminotransferase increase (0.7%). The most common adverse reactions (≥10%) of any grade reported in patients in the IBRANCE plus letrozole arm by descending frequency were neutropenia, infections, leukopenia, fatigue, nausea, alopecia, stomatitis, diarrhea, anemia, rash, asthenia, thrombocytopenia, vomiting, decreased appetite, dry skin, pyrexia, and dysgeusia. The most frequently reported Grade >3 adverse reactions (≥5%) in patients receiving IBRANCE plus letrozole by descending frequency were neutropenia, leukopenia, infections, and anemia. Adverse reactions (≥10%) reported in patients who received IBRANCE plus letrozole or placebo plus letrozole in Study 1 are listed in Table 4. Table 4. Adverse Reactions (≥10%) in Study 1 Adverse Reaction IBRANCE plus Letrozole (N=444) Placebo plus Letrozole(N=222) All Grades % Grade 3 % Grade 4 % All Grades % Grade 3 % Grade 4 % Infections and infestations Infectionsa 60b 6 1 42 3 0 Blood and lymphatic system disorders Neutropenia 80 56 10 6 1 1 Leukopenia 39 24 1 2 0 0 Anemia 24 5 <1 9 2 0 Thrombocytopenia 16 1 <1 1 0 0 Metabolism and nutrition disorders Decreased appetite 15 1 0 9 0 0 Nervous system disorders Dysgeusia 10 0 0 5 0 0 Gastrointestinal disorders Stomatitisc 30 1 0 14 0 0 Nausea 35 <1 0 26 2 0 Diarrhea 26 1 0 19 1 0 Vomiting 16 1 0 17 1 0 Skin and subcutaneous tissue disorders Alopecia 33d N/A N/A 16e N/A N/A Rashf 18 1 0 12 1 0 Dry skin 12 0 0 6 0 0 General disorders and administration site conditions Fatigue 37 2 0 28 1 0 Asthenia 17 2 0 12 0 0 Pyrexia 12 0 0 9 0 0 Grading according to CTCAE 4.0. CTCAE=Common Terminology Criteria for Adverse Events; N=number of patients; N/A=not applicable; a Infections includes all reported preferred terms (PTs) that are part of the System Organ Class Infections and infestations. b Most common infections (≥1%) include: nasopharyngitis, upper respiratory tract infection, urinary tract infection, oral herpes, sinusitis, rhinitis, bronchitis, influenza, pneumonia, gastroenteritis, conjunctivitis, herpes zoster, pharyngitis, cellulitis, cystitis, lower respiratory tract infection, tooth infection, gingivitis, skin infection, gastroenteritis viral, respiratory tract infection, respiratory tract infection viral, and folliculitis. c Stomatitis includes: aphthous stomatitis, cheilitis, glossitis, glossodynia, mouth ulceration, mucosal inflammation, oral pain, oral discomfort, oropharyngeal pain, and stomatitis. d Grade 1 events – 30%; Grade 2 events – 3%. e Grade 1 events – 15%; Grade 2 events – 1%. f Rash includes the following PTs: rash, rash maculo-papular, rash pruritic, rash erythematous, rash papular, dermatitis, dermatitis acneiform, and toxic skin eruption. Additional adverse reactions occurring at an overall incidence of <10.0% of patients receiving IBRANCE plus letrozole in Study 1 included alanine aminotransferase increased (9.9%), aspartate aminotransferase increased (9.7%), epistaxis (9.2%), lacrimation increased (5.6%), dry eye (4.1%), vision blurred (3.6%), and febrile neutropenia (2.5%). Table 5. Laboratory Abnormalities in Study 1 Laboratory Abnormality IBRANCE plus Letrozole (N=444) Placebo plus Letrozole (N=222) All Grades % Grade 3 % Grade 4 % All Grades % Grade 3 % Grade 4 % WBC decreased 97 35 1 25 1 0 Neutrophils decreased 95 56 12 20 1 1 Anemia 78 6 0 42 2 0 Platelets decreased 63 1 1 14 0 0 Aspartate aminotransferase increased 52 3 0 34 1 0 Alanine aminotransferase increased 43 2 <1 30 0 0 N=number of patients; WBC=white blood cells. Study 2: IBRANCE Plus Fulvestrant Patients With HR-positive, HER2-Negative Advanced Or Metastatic Breast Cancer Who Have Had Disease Progression On Or After Prior Adjuvant Or Metastatic Endocrine Therapy The safety of IBRANCE (125 mg/day) plus fulvestrant (500 mg) versus placebo plus fulvestrant was evaluated in Study 2 (PALOMA-3). The data described below reflect exposure to IBRANCE in 345 out of 517 patients with HR-positive, HER2-negative advanced or metastatic breast cancer who received at least 1 dose of IBRANCE plus fulvestrant in Study 2. The median duration of treatment for IBRANCE plus fulvestrant was 10.8 months while the median duration of treatment for placebo plus fulvestrant arm was 4.8 months. Dose reductions due to an adverse reaction of any grade occurred in 36% of patients receiving IBRANCE plus fulvestrant. No dose reduction was allowed for fulvestrant in Study 2. Permanent discontinuation associated with an adverse reaction occurred in 19 of 345 (6%) patients receiving IBRANCE plus fulvestrant, and in 6 of 172 (3%) patients receiving placebo plus fulvestrant. Adverse reactions leading to discontinuation for those patients receiving IBRANCE plus fulvestrant included fatigue (0.6%), infections (0.6%), and thrombocytopenia (0.6%). The most common adverse reactions (≥10%) of any grade reported in patients in the IBRANCE plus fulvestrant arm by descending frequency were neutropenia, leukopenia, infections, fatigue, nausea, anemia, stomatitis, diarrhea, thrombocytopenia, vomiting, alopecia, rash, decreased appetite, and pyrexia. The most frequently reported Grade ≥3 adverse reactions (≥5%) in patients receiving IBRANCE plus fulvestrant in descending frequency were neutropenia and leukopenia. Adverse reactions (≥10%) reported in patients who received IBRANCE plus fulvestrant or placebo plus fulvestrant in Study 2 are listed in Table 6. Table 6. Adverse Reactions (≥10%) in Study 2 Adverse Reaction IBRANCE plus Letrozole (N=345) Placebo plus Letrozole (N=172) All Grades % Grade 3 % Grade 4 % All Grades % Grade 3 % Grade 4 % Infections and infestations Infectionsa 47b 3 1 31 3 0 Blood and lymphatic system disorders Neutropenia 83 55 11 4 1 0 Leukopenia 53 30 1 5 1 1 Anemia 30 4 0 13 2 0 Thrombocytopenia 23 2 1 0 0 0 Metabolism and nutrition disorders Decreased appetite 16 1 0 8 1 0 Gastrointestinal disorders Nausea 34 0 0 28 1 0 Stomatitisc 28 1 0 13 0 0 Diarrhea 24 0 0 19 1 0 Vomiting 19 1 0 15 1 0 Skin and subcutaneous tissue disorders Alopecia 18d N/A N/A 6e N/A N/A Rashf 18 1 0 12 1 0 Dry skin 17 1 0 6 0 0 General disorders and administration site conditions Fatigue 41 2 0 29 1 0 Pyrexia 13 <1 0 5 0 0 Grading according to CTCAE 4.0. CTCAE=Common Terminology Criteria for Adverse Events; N=number of patients; N/A=not applicable; a Infections includes all reported preferred terms (PTs) that are part of the System Organ Class Infections and infestations. b Most common infections (≥1%) include: nasopharyngitis, upper respiratory tract infection, urinary tract infection, oral herpes, sinusitis, rhinitis, bronchitis, influenza, pneumonia, gastroenteritis, conjunctivitis, herpes zoster, pharyngitis, cellulitis, cystitis, lower respiratory tract infection, tooth infection, gingivitis, skin infection, gastroenteritis viral, respiratory tract infection, respiratory tract infection viral, and folliculitis. c Stomatitis includes: aphthous stomatitis, cheilitis, glossitis, glossodynia, mouth ulceration, mucosal inflammation, oral pain, oral discomfort, oropharyngeal pain, and stomatitis. d Grade 1 events –17%; Grade 2 events –1%. e Grade 1 events – 6%; f Rash includes the following PTs: rash, rash maculo-papular, rash pruritic, rash erythematous, rash papular, dermatitis, dermatitis acneiform, and toxic skin eruption. Additional adverse reactions occurring at an overall incidence of <10.0% of patients receiving IBRANCE plus fulvestrant in Study 2 included asthenia (7.5%), aspartate aminotransferase increased (7.5%), dysgeusia (6.7%), epistaxis (6.7%), lacrimation increased (6.4%), dry skin (6.1%), alanine aminotransferase increased (5.8%), vision blurred (5.8%), dry eye (3.8%), and febrile neutropenia (0.9%). Table 7. Laboratory Abnormalities in Study 2 Laboratory Abnormality IBRANCE plus Letrozole (N=345) Placebo plus Letrozole (N=172) All Grades % Grade 3 % Grade 4 % All Grades % Grade 3 % Grade 4 % WBC decreased 99 45 1 26 0 1 Neutrophils decreased 96 56 11 14 0 1 Anemia 78 3 0 40 2 0 Platelets decreased 62 2 1 10 0 0 Aspartate aminotransferase increased 43 4 0 48 4 0 Alanine aminotransferase increased 36 2 0 34 0 0 N=number of patients; WBC=white blood cells. DRUG INTERACTIONS Palbociclib is primarily metabolized by CYP3A and sulfotransferase (SULT) enzyme SULT2A1. In vivo, palbociclib is a time-dependent inhibitor of CYP3A. Agents That May Increase Palbociclib Plasma Concentrations Effect Of CYP3A Inhibitors Coadministration of a strong CYP3A inhibitor (itraconazole) increased the plasma exposure of palbociclib in healthy subjects by 87%. Avoid concomitant use of strong CYP3A inhibitors (e.g., clarithromycin, indinavir, itraconazole, ketoconazole, lopinavir/ritonavir, nefazodone, nelfinavir, posaconazole, ritonavir, saquinavir, telaprevir, telithromycin, and voriconazole). Avoid grapefruit or grapefruit juice during IBRANCE treatment. If coadministration of IBRANCE with a strong CYP3A inhibitor cannot be avoided, reduce the dose of IBRANCE [see DOSAGE AND ADMINISTRATION and CLINICAL PHARMACOLOGY]. Agents That May Decrease Palbociclib Plasma Concentrations Effect Of CYP3A Inducers Coadministration of a strong CYP3A inducer (rifampin) decreased the plasma exposure of palbociclib in healthy subjects by 85%. Avoid concomitant use of strong CYP3A inducers (e.g., phenytoin, rifampin, carbamazepine, enzalutamide, and St John’s Wort) [see CLINICAL PHARMACOLOGY]. Drugs That May Have Their Plasma Concentrations Altered By Palbociclib Coadministration of midazolam with multiple doses of IBRANCE increased the midazolam plasma exposure by 61%, in healthy subjects, compared to administration of midazolam alone. The dose of the sensitive CYP3A substrate with a narrow therapeutic index (e.g., alfentanil, cyclosporine, dihydroergotamine, ergotamine, everolimus, fentanyl, pimozide, quinidine, sirolimus, and tacrolimus) may need to be reduced, as IBRANCE may increase its exposure [see CLINICAL PHARMACOLOGY].

WARNINGS Included as part of the "PRECAUTIONS" Section PRECAUTIONS Neutropenia Neutropenia was the most frequently reported adverse reaction in Study 1 (PALOMA-2) with an incidence of 80% and Study 2 (PALOMA-3) with an incidence of 83%. A Grade ≥3 decrease in neutrophil counts was reported in 66% of patients receiving IBRANCE plus letrozole in Study 1 and 66% of patients receiving IBRANCE plus fulvestrant in Study 2. In Study 1 and 2, the median time to first episode of any grade neutropenia was 15 days and the median duration of Grade ≥3 neutropenia was 7 days [see ADVERSE REACTIONS]. Monitor complete blood counts prior to starting IBRANCE therapy and at the beginning of each cycle, as well as on Day 15 of the first 2 cycles, and as clinically indicated. Dose interruption, dose reduction, or delay in starting treatment cycles is recommended for patients who develop Grade 3 or 4 neutropenia [see DOSAGE AND ADMINISTRATION]. Febrile neutropenia has been reported in 1.8% of patients exposed to IBRANCE across Studies 1 and 2. One death due to neutropenic sepsis was observed in Study 2. Physicians should inform patients to promptly report any episodes of fever [see PATIENT INFORMATION]. Embryo-Fetal Toxicity Based on findings from animal studies and its mechanism of action, IBRANCE can cause fetal harm when administered to a pregnant woman. In animal reproduction studies, administration of palbociclib to pregnant rats and rabbits during organogenesis resulted in embryo-fetal toxicity at maternal exposures that were ≥4 times the human clinical exposure based on area under the curve (AUC). Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment with IBRANCE and for at least 3 weeks after the last dose [see Use In Specific Populations and CLINICAL PHARMACOLOGY]. Patient Counseling Information Advise the patient to read the FDA-approved patient labeling (Patient Information). Myelosuppression/Infection Advise patients to immediately report any signs or symptoms of myelosuppression or infection, such as fever, chills, dizziness, shortness of breath, weakness, or any increased tendency to bleed and/or to bruise [see WARNINGS AND PRECAUTIONS]. Drug Interactions Grapefruit may interact with IBRANCE. Patients should not consume grapefruit products while on treatment with IBRANCE. Inform patients to avoid strong CYP3A inhibitors and strong CYP3A inducers. Advise patients to inform their health care providers of all concomitant medications, including prescription medicines, over-the-counter drugs, vitamins, and herbal products [see DRUG INTERACTIONS]. Dosing And Administration Advise patients to take IBRANCE with food. If the patient vomits or misses a dose, an additional dose should not be taken. The next prescribed dose should be taken at the usual time. IBRANCE capsules should be swallowed whole (do not chew, crush, or open them prior to swallowing). No capsule should be ingested if it is broken, cracked, or otherwise not intact. Pregnancy, Lactation, And Fertility Embryo-Fetal Toxicity Advise females of reproductive potential of the potential risk to a fetus and to use effective contraception during treatment with IBRANCE therapy and for at least 3 weeks after the last dose. Advise females to inform their healthcare provider of a known or suspected pregnancy [see WARNINGS AND PRECAUTIONS and Use In Specific Populations]. Advise male patients with female partners of reproductive potential to use effective contraception during treatment with IBRANCE and for at least 3 months after the last dose [see Use In Specific Populations]. Lactation: Advise women not to breastfeed during treatment with IBRANCE and for 3 weeks after the last dose [see Use In Specific Populations]. This product’s label may have been updated. For full prescribing information, please visit www.IBRANCE.com. Nonclinical Toxicology Carcinogenesis, Mutagenesis, Impairment Of Fertility Carcinogenicity studies have not been conducted with palbociclib. Palbociclib was aneugenic in Chinese Hamster Ovary cells in vitro and in the bone marrow of male rats at doses ≥100 mg/kg/day for 3 weeks. Palbociclib was not mutagenic in an in vitro bacterial reverse mutation (Ames) assay and was not clastogenic in the in vitro human lymphocyte chromosome aberration assay. In a fertility study in female rats, palbociclib did not affect mating or fertility at any dose up to 300 mg/kg/day (approximately 4 times human clinical exposure based on AUC) and no adverse effects were observed in the female reproductive tissues in repeat-dose toxicity studies up to 300 mg/kg/day in the rat and 3 mg/kg/day in the dog (approximately 6 times and similar to human exposure [AUC], at the recommended dose, respectively). The adverse effects of palbociclib on male reproductive function and fertility were observed in the repeat-dose toxicology studies in rats and dogs and a male fertility study in rats. In repeat-dose toxicology studies, palbociclib-related findings in the testis, epididymis, prostate, and seminal vesicle at ≥30 mg/kg/day in rats and ≥0.2 mg/kg/day in dogs included decreased organ weight, atrophy or degeneration, hypospermia, intratubular cellular debris, and decreased secretion. Partial reversibility of male reproductive organ effects was observed in the rat and dog following a 4-and 12-week non-dosing period, respectively. These doses in rats and dogs resulted in approximately ≥10 and 0.1 times, respectively, the exposure [AUC] in humans at the recommended dose. In the fertility and early embryonic development study in male rats, palbociclib caused no effects on mating but resulted in a slight decrease in fertility in association with lower sperm motility and density at 100 mg/kg/day with projected exposure levels [AUC] of 20 times the exposure in humans at the recommended dose. Use In Specific Populations Pregnancy Risk Summary Based on findings from animal studies and its mechanism of action, IBRANCE can cause fetal harm when administered to a pregnant woman [see CLINICAL PHARMACOLOGY]. There are no available data in pregnant women to inform the drug-associated risk. In animal reproduction studies, administration of palbociclib to pregnant rats and rabbits during organogenesis resulted in embryofetal toxicity at maternal exposures that were ≥4 times the human clinical exposure based on AUC [see Data]. Advise pregnant women of the potential risk to a fetus. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2%-4% and 15%-20%, respectively. Data Animal Data In a fertility and early embryonic development study in female rats, palbociclib was administered orally for 15 days before mating through to Day 7 of pregnancy, which did not cause embryo toxicity at doses up to 300 mg/kg/day with maternal systemic exposures approximately 4 times the human exposure (AUC) at the recommended dose. In embryo-fetal development studies in rats and rabbits, pregnant animals received oral doses of palbociclib up to 300 mg/kg/day and 20 mg/kg/day, respectively, during the period of organogenesis. The maternally toxic dose of 300 mg/kg/day was fetotoxic in rats, resulting in reduced fetal body weights. At doses ≥100 mg/kg/day in rats, there was an increased incidence of a skeletal variation (increased incidence of a rib present at the seventh cervical vertebra). At the maternally toxic dose of 20 mg/kg/day in rabbits, there was an increased incidence of skeletal variations, including small phalanges in the forelimb. At 300 mg/kg/day in rats and 20 mg/kg/day in rabbits, the maternal systemic exposures were approximately 4 and 9 times the human exposure (AUC) at the recommended dose, respectively. CDK4/6 double knockout mice have been reported to die in late stages of fetal development (gestation Day 14.5 until birth) due to severe anemia. However, knockout mouse data may not be predictive of effects in humans due to differences in degree of target inhibition. Lactation Risk Summary There is no information regarding the presence of palbociclib in human milk, its effects on milk production, or the breastfed infant. Because of the potential for serious adverse reactions in breastfed infants from IBRANCE, advise a lactating woman not to breastfeed during treatment with IBRANCE and for 3 weeks after the last dose. Females And Males Of Reproductive Potential Pregnancy Testing Based on animal studies, IBRANCE can cause fetal harm when administered to a pregnant woman [see Pregnancy]. Females of reproductive potential should have a pregnancy test prior to starting treatment with IBRANCE. Contraception Females IBRANCE can cause fetal harm when administered to a pregnant woman [see Pregnancy]. Advise females of reproductive potential to use effective contraception during treatment with IBRANCE and for at least 3 weeks after the last dose. Males Because of the potential for genotoxicity, advise male patients with female partners of reproductive potential to use effective contraception during treatment with IBRANCE and for 3 months after the last dose [see Nonclinical Toxicology]. Infertility Males Based on animal studies, IBRANCE may impair fertility in males of reproductive potential [see Nonclinical Toxicology]. Pediatric Use The safety and efficacy of IBRANCE in pediatric patients have not been studied. Altered glucose metabolism (glycosuria, hyperglycemia, decreased insulin) associated with changes in the pancreas (islet cell vacuolation), eye (cataracts, lens degeneration), kidney (tubule vacuolation, chronic progressive nephropathy) and adipose tissue (atrophy) were identified in a 27 week repeat-dose toxicology study in rats that were immature at the beginning of the studies and were most prevalent in males at oral palbociclib doses ≥ 30 mg/kg/day (approximately 11 times the adult human exposure [AUC] at the recommended dose). Some of these findings (glycosuria/hyperglycemia, pancreatic islet cell vacuolation, and kidney tubule vacuolation) were present with lower incidence and severity in a 15 week repeat-dose toxicology study in immature rats. Altered glucose metabolism or associated changes in the pancreas, eye, kidney and adipose tissue were not identified in a 27-week repeat-dose toxicology study in rats that were mature at the beginning of the study and in dogs in repeat-dose toxicology studies up to 39 weeks duration. Toxicities in teeth independent of altered glucose metabolism were observed in rats. Administration of 100 mg/kg palbociclib for 27 weeks (approximately 15 times the adult human exposure [AUC] at the recommended dose) resulted in abnormalities in growing incisor teeth (discolored, ameloblast degeneration/necrosis, mononuclear cell infiltrate). Other toxicities of potential concern to pediatric patients have not been evaluated in juvenile animals. Geriatric Use Of 444 patients who received IBRANCE in Study 1, 181 patients (41%) were ≥65 years of age and 48 patients (11%) were ≥75 years of age. Of 347 patients who received IBRANCE in Study 2, 86 patients (25%) were ≥65 years of age and 27 patients (8%) were ≥75 years of age. No overall differences in safety or effectiveness of IBRANCE were observed between these patients and younger patients. Hepatic Impairment Based on a population pharmacokinetic analysis that included 183 patients, where 40 patients had mild hepatic impairment (total bilirubin ≤ ULN and AST > ULN, or total bilirubin >1.0 to 1.5 × ULN and any AST), mild hepatic impairment had no effect on the exposure of palbociclib. The pharmacokinetics of palbociclib have not been studied in patients with moderate or severe hepatic impairment (total bilirubin >1.5 × ULN and any AST) [see CLINICAL PHARMACOLOGY]. Review the Full Prescribing Information for the aromatase inhibitor or fulvestrant for dose modifications related to hepatic impairment. Renal Impairment Based on a population pharmacokinetic analysis that included 183 patients, where 73 patients had mild renal impairment (60 mL/min ≤ CrCl <90 mL/min) and 29 patients had moderate renal impairment (30 mL/min ≤ CrCl <60 mL/min), mild and moderate renal impairment had no effect on the exposure of palbociclib. The pharmacokinetics of palbociclib have not been studied in patients with severe renal impairment [see CLINICAL PHARMACOLOGY].