IBRANCE (Palbociclib)
CDK4/6 inhibitor for HR+/HER2- metastatic breast cancer
Quick Facts About IBRANCE
Key Takeaways About IBRANCE
- Combination therapy: IBRANCE is always used together with hormonal therapy (an aromatase inhibitor or fulvestrant) to treat HR+/HER2− metastatic breast cancer
- Cyclical dosing: Taken once daily for 21 days followed by 7 days off, in repeating 28-day cycles at a starting dose of 125 mg
- Neutropenia monitoring: Regular blood tests are essential because IBRANCE commonly causes low white blood cell counts, increasing infection risk
- Avoid certain substances: Grapefruit, St. John's wort, and strong CYP3A inhibitors or inducers can affect how IBRANCE works in the body
- Contraception required: Both women and men must use effective contraception during treatment and for a period after stopping IBRANCE due to potential harm to an unborn child
What Is IBRANCE and What Is It Used For?
IBRANCE (palbociclib) is a targeted anticancer medicine that works by blocking proteins called cyclin-dependent kinases 4 and 6 (CDK4/6), which regulate cell growth and division. It is used in combination with hormonal therapy to treat hormone receptor-positive, HER2-negative breast cancer that has spread to other parts of the body.
IBRANCE belongs to a relatively new class of cancer drugs known as CDK4/6 inhibitors, which have transformed the treatment landscape for advanced breast cancer since their introduction. The active substance, palbociclib, was the first CDK4/6 inhibitor to receive regulatory approval and has since become a cornerstone of first-line and second-line therapy for patients with HR+/HER2− metastatic breast cancer. It is manufactured by Pfizer and was approved by the U.S. Food and Drug Administration (FDA) in 2015 and the European Medicines Agency (EMA) in 2016.
Breast cancer is the most commonly diagnosed cancer worldwide, and approximately 70–80% of all breast cancers are classified as hormone receptor-positive (HR+). In these cancers, the tumor cells carry receptors for estrogen and/or progesterone, meaning their growth is driven by these hormones. HER2-negative (HER2−) indicates that the cancer cells do not overexpress the human epidermal growth factor receptor 2 protein, which distinguishes this subtype from HER2-positive breast cancers that require different treatment strategies.
IBRANCE is specifically indicated for adult patients with HR+/HER2− locally advanced or metastatic breast cancer. The term “locally advanced” means the cancer has grown beyond the breast into nearby tissues but has not yet spread to distant organs, while “metastatic” indicates that cancer cells have traveled to distant sites such as bones, lungs, liver, or brain. IBRANCE is prescribed in two main clinical settings:
- First-line treatment: In combination with an aromatase inhibitor (such as letrozole or anastrozole) as the initial endocrine-based therapy for metastatic disease
- Second-line treatment: In combination with fulvestrant for patients whose disease has progressed after prior endocrine therapy
How IBRANCE Works
To understand how IBRANCE works, it is helpful to understand the cell cycle — the series of tightly regulated steps that a cell goes through to divide and produce new cells. In healthy tissue, the cell cycle is carefully controlled by multiple checkpoints that ensure cells only divide when appropriate. Two key proteins in this process are cyclin-dependent kinase 4 (CDK4) and cyclin-dependent kinase 6 (CDK6), which act as molecular switches that drive cells from the G1 phase (growth and preparation) into the S phase (DNA replication).
In HR+ breast cancer, the signaling pathways that activate CDK4 and CDK6 are frequently dysregulated. Estrogen receptor signaling promotes the production of cyclin D proteins, which bind to and activate CDK4/6. This drives excessive cell cycling, allowing cancer cells to proliferate in an uncontrolled manner. By selectively and reversibly inhibiting CDK4 and CDK6, palbociclib prevents the phosphorylation of the retinoblastoma protein (Rb), a key gatekeeper of the cell cycle. When Rb remains unphosphorylated, it continues to suppress the activity of E2F transcription factors needed for DNA synthesis, effectively arresting cancer cells in the G1 phase and preventing them from dividing.
The combination of IBRANCE with endocrine therapy is synergistic. While hormonal agents such as aromatase inhibitors reduce estrogen levels (depriving cancer cells of their growth signal), IBRANCE simultaneously blocks the downstream cell cycle machinery. This dual attack addresses both the hormonal driver and the cell proliferation pathway, making it significantly more effective than hormonal therapy alone.
Landmark clinical trials have confirmed the benefit of this approach. The PALOMA-2 trial demonstrated that the combination of palbociclib with letrozole nearly doubled median progression-free survival (24.8 months vs. 14.5 months) compared with letrozole alone in first-line treatment. Similarly, the PALOMA-3 trial showed that palbociclib combined with fulvestrant significantly improved progression-free survival (9.5 months vs. 4.6 months) in patients who had progressed on prior endocrine therapy. These pivotal studies established IBRANCE as a standard of care for HR+/HER2− advanced breast cancer.
IBRANCE does not work as a standalone treatment. It must always be taken together with hormonal therapy (an aromatase inhibitor or fulvestrant). Taking IBRANCE without the companion hormonal therapy significantly reduces its effectiveness. Your oncologist will determine the most appropriate hormonal treatment partner based on your individual clinical situation.
What Should You Know Before Taking IBRANCE?
Before starting IBRANCE, you must inform your doctor about all medical conditions, allergies, medications, and supplements. IBRANCE should not be taken if you are allergic to palbociclib, and certain conditions and medications require special precautions. Regular blood count monitoring is mandatory throughout treatment.
Starting treatment with IBRANCE requires careful evaluation by your oncologist and open communication about your complete medical history. Because IBRANCE affects rapidly dividing cells — including some healthy cells like those in the bone marrow — your healthcare team needs a thorough understanding of your baseline health to manage treatment safely and effectively. The following sections outline the key considerations before beginning therapy.
Contraindications
You must not take IBRANCE if:
- You are allergic (hypersensitive) to palbociclib or any of the other ingredients in the formulation (including microcrystalline cellulose, colloidal silicon dioxide, crospovidone, magnesium stearate, or succinic acid in the tablet core, or the film-coating components)
- You are currently using products containing St. John's wort (Hypericum perforatum), a herbal remedy sometimes used for mild depression and anxiety. St. John's wort is a potent CYP3A inducer and can dramatically reduce IBRANCE blood levels, rendering the treatment ineffective
If you are uncertain whether any product you are using contains St. John's wort, consult your doctor or pharmacist before starting IBRANCE.
Warnings and Precautions
Talk to your doctor, pharmacist, or nurse before taking IBRANCE, and be aware of the following important safety considerations:
Neutropenia (low white blood cell count): The most significant and most common side effect of IBRANCE is a reduction in white blood cells, particularly neutrophils. Neutrophils are a critical component of your immune defense, and when their numbers fall below safe levels (a condition called neutropenia), you become more vulnerable to infections. Your doctor will perform a complete blood count before starting IBRANCE, at the beginning of each new cycle, on day 15 of the first two cycles, and whenever clinically indicated. If your neutrophil counts drop too low, your doctor may need to reduce your dose, delay the next cycle, or temporarily pause treatment until your counts recover.
Infections: Because IBRANCE weakens your immune system, you must be vigilant for signs and symptoms of infection. Contact your healthcare team immediately if you develop fever, chills, sore throat, cough, shortness of breath, body aches, or any other signs suggestive of an infection. Even seemingly minor infections can escalate quickly when your immune system is compromised. Your doctor may prescribe preventive antibiotics in some cases.
Venous thromboembolism (blood clots): IBRANCE has been associated with blood clots forming in the veins, which can be dangerous. Contact your doctor immediately if you experience pain or swelling in a leg or arm, chest pain, sudden shortness of breath, rapid breathing, or a feeling of faintness. Venous thromboembolism requires urgent medical attention and may necessitate anticoagulation therapy.
Interstitial lung disease / pneumonitis: In some patients, IBRANCE can cause serious or life-threatening inflammation of the lungs. Symptoms include new or worsening difficulty breathing, shortness of breath, dry cough, and chest pain. If you experience any of these symptoms, seek medical attention immediately. Your doctor may need to permanently discontinue IBRANCE if interstitial lung disease is confirmed.
Contact your doctor or go to the emergency department immediately if you develop: fever above 38°C (100.4°F), signs of infection (chills, sore throat, cough), difficulty breathing or chest pain, or sudden swelling, pain, or redness in a leg or arm. These may indicate serious complications requiring urgent treatment.
Pregnancy and Breastfeeding
IBRANCE can cause harm to a developing fetus and must not be used during pregnancy. If you are pregnant, think you may be pregnant, or are planning to have a baby, discuss this with your doctor before starting treatment.
- Women of childbearing potential must use effective contraception during treatment with IBRANCE and for at least 3 weeks after the last dose. Your doctor may recommend using two forms of contraception (dual barrier methods such as condoms and a diaphragm)
- Male patients with female partners of childbearing potential must use effective contraception during treatment and for at least 14 weeks after the last dose
- Breastfeeding: You should not breastfeed while taking IBRANCE. It is not known whether palbociclib passes into breast milk, and a risk to the breastfed infant cannot be excluded
- Fertility: Palbociclib may reduce fertility in men. Male patients should consider sperm preservation (cryopreservation) before beginning treatment
Driving and Operating Machinery
Fatigue is a very common side effect of IBRANCE, reported by a significant proportion of patients. If you feel unusually tired, drowsy, or weak, exercise particular caution when driving motor vehicles or operating machinery. Assess how you feel before undertaking activities that require alertness, and discuss any concerns with your healthcare team.
Children and Adolescents
IBRANCE is not approved for use in children or adolescents under 18 years of age. The safety and efficacy of palbociclib in the pediatric population have not been established.
How Does IBRANCE Interact with Other Drugs?
IBRANCE is metabolized primarily by the CYP3A enzyme system, making it susceptible to significant interactions with drugs that inhibit or induce CYP3A. Strong CYP3A inhibitors can increase palbociclib levels and toxicity, while strong CYP3A inducers can reduce its effectiveness. Grapefruit and grapefruit juice must also be avoided.
Drug interactions are a critical consideration when taking IBRANCE, as palbociclib is primarily metabolized by the liver enzyme CYP3A4. Substances that strongly affect the activity of this enzyme can dramatically alter the concentration of palbociclib in your blood, either increasing side effect risk or reducing therapeutic benefit. Always inform your oncologist, pharmacist, and other healthcare providers about all medications, supplements, herbal products, and over-the-counter remedies you are taking before starting IBRANCE and at every follow-up appointment.
Major Interactions — Drugs That Increase IBRANCE Side Effects
The following medications are strong CYP3A inhibitors and can significantly increase the concentration of palbociclib in your blood, amplifying the risk of adverse effects. If any of these cannot be avoided, your doctor may need to reduce your IBRANCE dose:
| Drug | Therapeutic Use | Interaction Risk |
|---|---|---|
| Ketoconazole, itraconazole, voriconazole, posaconazole | Antifungal medications | High — significant increase in palbociclib levels |
| Clarithromycin, telithromycin | Antibiotic medications | High — inhibits palbociclib metabolism |
| Ritonavir, lopinavir, indinavir, nelfinavir, saquinavir, telaprevir | HIV/AIDS antiviral medications | High — strong CYP3A inhibition |
| Nefazodone | Antidepressant | High — potent CYP3A inhibitor |
| Grapefruit, grapefruit juice | Dietary | Moderate to High — avoid during treatment |
Drugs Whose Effects May Be Increased by IBRANCE
Palbociclib can also affect the metabolism of certain other medications, potentially increasing their plasma concentrations and toxicity. Your doctor may need to adjust the doses of these medications while you are on IBRANCE:
| Drug | Therapeutic Use | Clinical Concern |
|---|---|---|
| Fentanyl, alfentanil | Opioid pain relief / anesthesia | Increased sedation and respiratory depression risk |
| Cyclosporine, everolimus, tacrolimus, sirolimus | Immunosuppressants (organ transplant) | Increased immunosuppression and toxicity |
| Dihydroergotamine, ergotamine | Migraine treatment | Risk of ergotism (vasospasm) |
| Pimozide | Antipsychotic | QT prolongation risk |
| Quinidine | Heart rhythm disorders | Cardiac arrhythmia risk |
| Simvastatin, atorvastatin, pravastatin, fluvastatin, rosuvastatin | Cholesterol-lowering statins | Increased statin levels; myopathy risk |
| Sulfasalazine | Rheumatoid arthritis | Increased sulfasalazine exposure |
| Colchicine | Gout treatment | Colchicine toxicity risk |
Drugs That May Reduce IBRANCE Effectiveness
The following medications are strong CYP3A inducers that can dramatically lower palbociclib blood levels, potentially making the treatment ineffective. Concomitant use should be avoided whenever possible:
- Rifampin — used to treat tuberculosis (TB)
- Carbamazepine, phenytoin — anticonvulsant medications for epilepsy
- Enzalutamide — used to treat prostate cancer
- St. John's wort (Hypericum perforatum) — herbal product for mild depression and anxiety. Must be completely avoided during IBRANCE treatment
Avoid grapefruit and grapefruit juice while taking IBRANCE. Grapefruit contains compounds (furanocoumarins) that inhibit the CYP3A enzyme in the gut wall, which can increase the absorption of palbociclib and raise blood levels beyond the intended therapeutic range. This may increase the risk and severity of side effects. Other citrus fruits such as oranges, lemons, and limes are safe to consume.
What Is the Correct Dosage of IBRANCE?
The recommended starting dose of IBRANCE is 125 mg taken once daily for 21 consecutive days, followed by 7 days off treatment, in a repeating 28-day cycle. Tablets should be swallowed whole with water at approximately the same time each day, with or without food. Your doctor may reduce the dose to 100 mg or 75 mg if you experience certain side effects.
IBRANCE follows a cyclical dosing schedule designed to balance antitumor efficacy with manageable side effects. The “3 weeks on, 1 week off” pattern allows your bone marrow time to recover from the neutropenia that commonly occurs during treatment. Always take IBRANCE exactly as prescribed by your doctor or pharmacist, and never adjust your dose on your own.
Adults
Standard Dosing Schedule
Starting dose: 125 mg once daily
Schedule: Take for 21 consecutive days, then stop for 7 days (28-day cycle)
Administration: Swallow the tablet whole with a glass of water. Do not chew, crush, or split the tablets. Do not take a tablet that is broken, cracked, or otherwise not intact.
Timing: Take at approximately the same time each day, with or without food
Companion therapy: Always taken together with an aromatase inhibitor or fulvestrant, as prescribed by your oncologist
Dose Reductions
If you develop certain side effects (particularly severe neutropenia or other significant toxicities), your doctor may reduce your dose in a stepwise manner:
- First dose reduction: From 125 mg to 100 mg once daily
- Second dose reduction: From 100 mg to 75 mg once daily
If further dose reduction below 75 mg daily is required, your oncologist may consider discontinuing treatment, as this is the lowest recommended dose. Never adjust your dose without consulting your doctor first.
Children
IBRANCE is not indicated for use in children or adolescents under 18 years of age. No pediatric dosing recommendations are available.
Elderly
No specific dose adjustments are required for elderly patients based on age alone. However, elderly patients may be more susceptible to certain side effects, and careful monitoring is essential. Your oncologist will assess your overall health, organ function, and ability to tolerate treatment when determining the appropriate dose.
Missed Dose
If you miss a dose of IBRANCE, or if you vomit after taking a dose, do not take a replacement dose. Simply take your next dose at the regularly scheduled time on the following day. Do not take a double dose to make up for a missed one. If you are unsure about what to do, contact your pharmacist or doctor for guidance.
Overdose
If you take more IBRANCE than prescribed, contact your doctor or go to a hospital emergency department immediately. Bring the medicine packaging and this information with you so that medical professionals know what you have taken. In the event of overdose, your doctor will provide supportive care and monitor your blood counts closely, as exaggerated neutropenia is the primary concern.
Do not stop taking IBRANCE unless your doctor tells you to do so. Even if you feel well, the medication is working to slow the growth of cancer cells. Stopping treatment prematurely may allow the cancer to progress. If you have concerns about side effects or any aspect of your treatment, discuss them with your oncology team rather than stopping on your own.
What Are the Side Effects of IBRANCE?
Like all medicines, IBRANCE can cause side effects, though not everyone experiences them. The most common side effect is neutropenia (low white blood cell count), affecting the majority of patients. Other frequent side effects include fatigue, nausea, mouth sores, hair loss, diarrhea, and rash. Some side effects can be serious and require immediate medical attention.
Understanding the potential side effects of IBRANCE helps you recognize symptoms early and seek timely medical intervention when necessary. The side effects listed below are classified by how commonly they occur, based on data from clinical trials and post-marketing surveillance. Your oncology team will monitor you closely for side effects throughout treatment and can often manage them effectively with dose adjustments, supportive medications, or temporary treatment interruptions.
Fever, chills, weakness, shortness of breath, bleeding, or tendency to bruise easily (which may indicate a serious blood disorder); difficulty breathing, dry cough, or chest pain (which may indicate lung inflammation); or a painful swollen leg, chest pain, shortness of breath, rapid breathing, or rapid heartbeat (which may indicate blood clots in the veins).
Very Common
- Infections (upper respiratory tract infections, urinary tract infections)
- Decreased white blood cells (neutropenia, leukopenia)
- Decreased red blood cells (anemia)
- Decreased platelets (thrombocytopenia)
- Fatigue and weakness (asthenia)
- Decreased appetite
- Mouth sores and lip inflammation (stomatitis)
- Nausea
- Vomiting
- Diarrhea
- Hair loss (alopecia)
- Skin rash
- Dry skin
- Fever (pyrexia)
- Abnormal liver function test results
Common
- Febrile neutropenia (fever with dangerously low white blood cell count)
- Blurred vision, watery eyes, dry eyes
- Altered taste (dysgeusia)
- Nosebleeds (epistaxis)
- Redness, pain, peeling skin, swelling and blistering on palms and/or soles (palmar-plantar erythrodysaesthesia syndrome / PPES)
- Abnormal kidney function test results (elevated blood creatinine)
Uncommon
- Cutaneous lupus erythematosus (CLE) — skin inflammation causing red, scaly patches, possibly with joint pain and fever
- Erythema multiforme — a skin reaction causing red spots or patches that may look like a target with a dark red center surrounded by paler red rings
- Interstitial lung disease / pneumonitis
Rare / Post-Marketing Reports
- Severe skin reactions (toxic epidermal necrolysis has been reported with other CDK4/6 inhibitors in the same class)
- Venous thromboembolism (deep vein thrombosis and pulmonary embolism)
Managing Side Effects
Many side effects of IBRANCE can be effectively managed. Neutropenia, while common, is typically manageable through regular blood count monitoring and dose adjustments. Fatigue may be improved through light physical activity, adequate rest, and good nutrition. Mouth sores can be managed with gentle oral hygiene and prescribed mouth rinses. Hair loss from IBRANCE is usually milder than what occurs with traditional chemotherapy and is often reversible after treatment ends.
Your oncology team has extensive experience in managing these side effects and will work with you to optimize your quality of life during treatment. Always report new or worsening symptoms to your healthcare team promptly, even if they seem minor, as early intervention is typically more effective than waiting until symptoms become severe.
How Should You Store IBRANCE?
Store IBRANCE in its original blister packaging to protect it from moisture. No special temperature requirements apply. Keep the medicine out of the sight and reach of children, and do not use it after the expiry date printed on the packaging.
Proper storage of IBRANCE ensures the medication retains its effectiveness and safety throughout its shelf life. Follow these storage guidelines carefully:
- Temperature: No special temperature requirements. Store at room temperature, avoiding extreme heat or cold
- Moisture protection: Keep tablets in the original blister packaging at all times until ready to take a dose. The blister packaging is specifically designed to protect the tablets from moisture
- Damaged tablets: Do not use any tablet that appears broken, cracked, or otherwise damaged. If you notice damage to the blister pack or tablets, contact your pharmacist
- Expiry date: Check the expiry date on the blister and carton. The expiry date refers to the last day of the stated month. Do not use the medicine after this date
- Children: Keep out of the sight and reach of children at all times
- Disposal: Do not dispose of unused IBRANCE in household waste or down the drain. Return unused or expired tablets to your pharmacy for safe disposal. This protects the environment and prevents accidental exposure
What Does IBRANCE Contain?
The active ingredient in IBRANCE is palbociclib, available as film-coated tablets in three strengths: 75 mg, 100 mg, and 125 mg. The tablets also contain several inactive ingredients in the core and film coating.
Each IBRANCE film-coated tablet contains the active substance palbociclib in the following strengths:
- IBRANCE 75 mg: Round, light purple film-coated tablet marked “Pfizer” on one side and “PBC 75” on the other
- IBRANCE 100 mg: Oval, green film-coated tablet marked “Pfizer” on one side and “PBC 100” on the other
- IBRANCE 125 mg: Oval, light purple film-coated tablet marked “Pfizer” on one side and “PBC 125” on the other
Inactive Ingredients
In addition to the active substance, each tablet contains the following excipients:
| Component | Ingredients |
|---|---|
| Tablet core | Microcrystalline cellulose, colloidal silicon dioxide, crospovidone, magnesium stearate, succinic acid |
| Film coating (all strengths) | Hypromellose (E464), titanium dioxide (E171), triacetin, indigo carmine aluminium lake (E132) |
| Additional (75 mg & 125 mg only) | Red iron oxide (E172) |
| Additional (100 mg only) | Yellow iron oxide (E172) |
Pack Sizes
IBRANCE is available in blister packs containing 21 or 63 film-coated tablets. A wallet-style blister pack containing 7 tablets (one per cell) is also available, with each carton containing 21 tablets (3 wallet packs per carton). Not all pack sizes may be marketed in every country. Your pharmacist will dispense the appropriate pack for your prescription.
Frequently Asked Questions About IBRANCE
IBRANCE (palbociclib) is a targeted cancer therapy that belongs to a class of drugs called CDK4/6 inhibitors. It is used to treat adults with hormone receptor-positive, HER2-negative (HR+/HER2−) breast cancer that has spread beyond the original tumor (locally advanced or metastatic). IBRANCE works by blocking proteins called cyclin-dependent kinases 4 and 6, which regulate cell growth and division, thereby slowing the growth of cancer cells. It is always used in combination with hormonal therapy, either an aromatase inhibitor or fulvestrant.
The most common side effects of IBRANCE include neutropenia (low white blood cell count), fatigue, nausea, mouth sores (stomatitis), hair loss, diarrhea, decreased appetite, vomiting, rash, weakness, and fever. Neutropenia is the most frequently reported side effect and requires regular blood count monitoring. Most side effects can be managed with dose adjustments, supportive care, or temporary treatment interruptions.
IBRANCE should be taken once daily at approximately the same time each day, with or without food. The recommended starting dose is 125 mg taken for 21 consecutive days followed by 7 days off treatment, completing a 28-day cycle. Tablets should be swallowed whole with water and must not be chewed, crushed, or split. If a dose is missed or vomited, do not take a replacement dose; take the next dose at the scheduled time.
Yes, IBRANCE can interact with several medications. Strong CYP3A inhibitors such as ketoconazole, itraconazole, clarithromycin, and ritonavir can increase palbociclib levels and side effect risk. Strong CYP3A inducers like rifampin, phenytoin, and carbamazepine can reduce its effectiveness. St. John's wort must be avoided entirely. Grapefruit and grapefruit juice should also be avoided. Always inform your doctor about all medications, supplements, and herbal products you are taking.
No. IBRANCE must not be used during pregnancy as it may harm the developing baby. Women of childbearing potential and their male partners must use effective contraception during treatment and for at least 3 weeks after the last dose for women and 14 weeks for men. Breastfeeding is also not recommended during treatment. Men should consider sperm preservation before starting IBRANCE, as palbociclib may reduce male fertility.
IBRANCE should be stored in its original blister packaging to protect it from moisture. There are no special temperature requirements for storage. Keep it out of the sight and reach of children. Do not use the medicine after the expiry date printed on the blister and carton. Do not use tablets that appear damaged, cracked, or otherwise not intact.
References
- European Medicines Agency (EMA). IBRANCE – Summary of Product Characteristics. European Public Assessment Report. Available at: ema.europa.eu. Last updated 2025.
- U.S. Food and Drug Administration (FDA). Ibrance (palbociclib) – Prescribing Information. FDA Label. Available at: fda.gov.
- Finn RS, Martin M, Rugo HS, et al. Palbociclib and Letrozole in Advanced Breast Cancer. New England Journal of Medicine. 2016;375(20):1925–1936. doi:10.1056/NEJMoa1607303.
- Turner NC, Ro J, André F, et al. Palbociclib in Hormone-Receptor–Positive Advanced Breast Cancer. New England Journal of Medicine. 2015;373(3):209–219. doi:10.1056/NEJMoa1505270.
- National Comprehensive Cancer Network (NCCN). Clinical Practice Guidelines in Oncology: Breast Cancer. Version 2.2025.
- Cardoso F, Paluch-Shimon S, Senkus E, et al. 5th ESO-ESMO international consensus guidelines for advanced breast cancer (ABC 5). Annals of Oncology. 2020;31(12):1623–1649. doi:10.1016/j.annonc.2020.09.010.
- World Health Organization (WHO). Breast Cancer Fact Sheet. WHO Global Health Observatory. Available at: who.int.
- British National Formulary (BNF). Palbociclib – Drug Monograph. National Institute for Health and Care Excellence (NICE). Available at: bnf.nice.org.uk.
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