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Treatment Name: Abemaciclib (Verzenio®) + Fulvestrant (Faslodex®)

Abemaciclib (Verzenio®) + Fulvestrant (Faslodex®) is a Chemotherapy Regimen for Breast Cancer - metastatic

How does abemaciclib + fulvestrant work?

  • Abemaciclib is designed to inhibit a specific protein that is responsible for turning off tumor suppressor genes and allowing the cancer cell to grow and divide. By inhibiting this protein, abemaciclib causes the cell to stop actively dividing (growing)
  • Fulvestrant is designed to block estrogen receptors on the surface of breast cancer cells. In patients with Estrogen Receptor positive (ER+) disease, estrogen binds to these receptors and tells the breast cancer cells to grow and divide. Fulvestrant blocks this signal and helps stop the breast cancer cells from growing

Goals of therapy:
Abemaciclib + fulvestrant is taken to slow the growth of breast cancer and prevent it from spreading further. The chemotherapy drug combination of Abemaciclib + Fulvestrant is not commonly given with the goal of cure.


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  • Fulvestrant intramuscular (I.M.) injection on Days 1 and 15 of Cycle 1, then on Day 1 of subsequent (later) cycles
  • Abemaciclib usual starting dose: 150 mg oral tablet by mouth twice daily

Abemaciclib is usually taken at home. Fulvestrant is usually given in an outpatient infusion center or a doctor’s clinic, allowing the person to go home afterwards.

Abemaciclib + fulvestrant is repeated every 28 days. This is known as one Cycle. Treatment is continued until it no longer works or until unacceptable side effects occur.

Click here for the common abemaciclib + fulvestrant starting doses.

Side Effects

In clinical studies, the most common side effects of abemaciclib + fulvestrant are shown here:

A note about side effect percentages

  • Diarrhea (86%)
  • Low white blood cells [neutropenia] (46%)
  • Nausea (45%)
  • Fatigue (40%)
  • Stomach pain (35%)
  • Low red blood cells [anemia] (29%)
  • Decreased appetite (27%)
  • Vomiting (26%)
  • Headache (20%)
  • Altered taste (18%)
  • Low platelets [thrombocytopenia] (16%)
  • Hair loss (16%)
  • Mouth sores (15%)
  • Constipation (14%)
  • Liver injury (13%)
  • Cough (13%)
  • Itching (13%)
  • Dizziness (13%)
  • Joint pain (12%)
  • Increase in blood creatinine levels (12%)
  • Swelling in legs and arms (12%)
  • Skin rash (11%)
  • Sinus infection (11%)
  • Shortness of breath (11%)
  • Fever (11%)
  • Muscle weakness (11%)
  • Hot flash (10%)
  • Weight loss (10%)
  • Back pain (10%)
  • Blood clots (2%)
  • Neutropenic fever (1%)

On average, 16% of patients discontinue Verzenio® (abemaciclib) + Faslodex® (fulvestrant) treatment due to unacceptable side effects.

Importantly, not all people who experience a side effect from Verzenio® (abemaciclib) + Faslodex® (fulvestrant) will experience it in the same way. It may be mild in some or severe in others, depending upon the individual. Everybody is different. Additionally, side effects may vary over time. For some, side effects may be a reason to delay or switch treatment, reduce the dose, or avoid future treatment with a certain medication altogether.

Side effects may be treatable when they occur or preventable by taking certain medications before they happen. When medications are taken to prevent a problem, this is known as prophylaxis, or "prophy" for short.

After starting treatment with Verzenio® + Faslodex®, be sure to come back and watch all of the side effect videos shown below. Each of these videos contain valuable information about side effect management that will hopefully help you to both feel better and stay out of the hospital.

Side effect videos Side Effect Videos
DiarrheaDiarrheaNausea and VomitingNausea and VomitingFatigue Fatigue PainPainAnemiaAnemiaHair LossHair LossConstipationConstipationBlood ClotsBlood ClotsNeutropenic FeverNeutropenic Fever


How often is monitoring needed?
Labs (blood tests) may be checked before treatment and periodically during treatment. Labs often include: Complete Blood Count (CBC), Comprehensive Metabolic Panel (CMP), plus any others your doctor may order.

How often is imaging needed?
Imaging may be checked before treatment and during treatment at the discretion of your doctor. Imaging may include: X-rays, magnetic resonance imaging (MRI), computerized tomography (CT) scans, or positron emission tomography (PET) scans.

How might blood test results/imaging affect treatment?
Depending upon the results, your doctor may advise to continue abemaciclib + fulvestrant as planned, reduce the dose, delay treatment until the side effect goes away, or switch to an alternative therapy.

ChemoExperts Tips

  • Diarrhea is a common side effect of abemaciclib and occurs most often during the first month of treatment. Be sure to drink plenty of fluids to stay hydrated. These symptoms may be managed with over-the-counter (OTC) medications such as loperamide (Imodium®)
  • Only a certain amount of fluid volume can be given by intramuscular (I.M.) injection at one time. Because of this, the total dose of fulvestrant must be given as two separate injections on the same day. Each injection will be given slowly over 1 to 2 minutes, one in each buttock
  • Changes in blood creatinine levels (a marker for kidney function) may happen during therapy with abemaciclib; however, significant kidney injury is not common
  • A pharmacist should ALWAYS review your medication list to ensure that drug interactions are prevented or managed appropriately
  • Clinical trials may exist for breast cancer. Ask your doctor if any studies are currently enrolling in your area. If not, go to to search for other centers offering study medications

Patient Assistance & Co-payment Coverage

Patients under the age of 65 years, or those with private insurance plans:
If you have insurance and are looking for patient assistance or copay assistance for Abemaciclib (Verzenio®) + Fulvestrant (Faslodex®), we have provided links that may help.

Visit our Patient Assistance page and click the links to various patient assistance programs for help paying for Abemaciclib (Verzenio®) + Fulvestrant (Faslodex®). Depending upon your income, they may be able to help cover the cost of:

  • Abemaciclib
  • Fulvestrant

For Branded medications (may be available for generic medications too), check with the manufacturer to determine if a co-pay card is offered and if it could reduce your monthly copay.

  • If you are uninsured, check with the manufacturer to determine if you are eligible to receive medication at no cost.

Medicare and Medicaid patients (Patients 65 years or older):
The clinic providing treatment will likely pre-authorize medications and immune therapies such as Abemaciclib (Verzenio®) + Fulvestrant (Faslodex®) and are the best source to help you understand drug cost.

  • Ask to speak with a patient assistance technician or financial counselor at the clinic or hospital administering this therapy.

Emotional Wellness

What is Emotional Wellness?
Emotional wellness is having a positive outlook balanced with a realistic understanding of current life events. This requires both an awareness and acceptance of your emotions. It is with this knowledge that you can develop a plan to take the necessary actions to positively impact your life.

Emotional wellness uses an ongoing process to continually reflect on the stressors of life in a constructive manner to move forward and create happiness.

Because emotional wellness is deeply connected with physical, social, and spiritual wellness, pursuing it often becomes particularly difficult in times of major illness. Despite this difficulty, working toward emotional wellness has been connected to improved treatment outcomes and a higher likelihood of achieving goals of therapy.

Learn more about pursuing emotional wellness while receiving treatment with Abemaciclib (Verzenio®) + Fulvestrant (Faslodex®)

Individual Drug Label Information

Abemaciclib (Verzenio®)

  • Is an oral tablet available in 50 mg, 100 mg, 150 mg, and 200 mg strengths
  • Can be taken with or without food. Swallow tablets whole and do not crush, chew, or break tablets
  • If you miss a dose, do not double-up at the next regular scheduled time. 
  • Stored tablets at room temperature (68°F to 77°F)
  • Dosage adjustments may be required if certain side effects happen or for certain drug interactions
  • May interact with certain antifungal and seizure medications. Ask your doctor or pharmacist to review your medications for any possible interactions 
  • May interact with grapefruit and grapefruit juice causing increased blood levels of abemaciclib. This could increase your risk of experiencing side effects. Avoid eating grapefruit and drinking anything containing grapefruit juice during treatment
  • May cause fetal harm if taken while pregnant or while breast-feeding. Use effective contraception and do not breast feed during therapy and for 3 weeks after discontinuing therapy
General side effects from abemaciclib tablets:
  • Increase in blood creatinine levels
  • Diarrhea
  • Low white blood cells, red blood cells, and platelets
  • Liver toxicity
  • Fatigue
  • Nausea/vomiting
  • Decreased appetite
  • Stomach pain
  • Infections
  • Headache
  • Click on the "See DailyMed package insert" link below for complete reported side effects, possible drug interactions, and other abemaciclib prescribing information

Side Effect Videos
Nausea and VomitingNausea and VomitingDiarrheaDiarrheaFatigue Fatigue PainPainAnemiaAnemia

See DailyMed package insert.

Fulvestrant (Faslodex®)

  • Fulvestrant is a intramuscular (I.M.) injection 
  • Dosage adjustments may be required for decreased liver function
  • Should only be given to post-menopausal women
  • Can cause fetal harm when given to pregnant women.  Women of childbearing age should be advised not to become pregnant
General Fulvestrant (Faslodex) Side Effects
  • One of the most common side effects reported are hot flashes. Talk to your doctor about ways to minimize and treat hot flashes. Do not take any medicines, herbs, or natural supplements without speaking with your doctor or pharmacist first
  • Injection site pain
  • Headache
  • Bone and join pain
  • Weakness
  • Nausea/Vomiting
  • Constipation or diarrhea
  • Fatigue
  • Shortness of breath
  • Click on the "See DailyMed package insert" below for complete reported side effects and possible drug interactions

Side Effect Videos
Nausea and VomitingNausea and VomitingDiarrheaDiarrheaFatigue Fatigue ConstipationConstipationPainPain

See DailyMed package insert.

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Sledge GW Jr, Toi M, Neven P, et al. MONARCH 2: Abemaciclib in Combination With Fulvestrant in Women With HR+/HER2- AdvancedBreast Cancer Who Had Progressed While Receiving Endocrine Therapy. J Clin Oncol 2017;35(25):2875-2884

Created: July 12, 2018 Updated: January 7, 2020

What is Breast Cancer - metastatic?

What is Metastatic Breast Cancer?
A disease of the milk-producing glands known as lobules, milk ducts, or other cells found in the breast. Metastatic breast cancer is one that has moved from the breast to other areas of the body, which may include the brain, liver, or bone. Breast cancer is one of the most common types of cancers in women, but may rarely affect men as well. Known causes of breast cancer include genetic causes, such as the BRCA mutation, or obesity. The effectiveness of the treatment may depend upon the stage at diagnosis.

Types of metastatic breast cancer:
1. Hormone-receptor positive or negative (60 - 65% of patients)

  • Estrogen Receptor positive (ER)+ or negative (ER)-
  • Progestin Receptor positive (PR)+ or negative (PR)-

2. Hormone Epidermal growth factor Receptor-2 (HER-2) positive or negative (20 - 25% of patients)

  • HER-2 +
  • HER-2 -

3. Triple Negative (15 - 18% of patients)

  • ER- and PR- and (HER-2)-
NOTE: Treatment Options listed below are not all-inclusive. Other treatments may be available. ChemoExperts provides drug information and does not recommend any one treatment over another. Only your Doctor can choose which therapy is appropriate for you.

What does Cure mean?

The word “cure” means there are no cancer cells left in the body and cancer will never come back. Depending on the cancer type and stage, this may be the true goal of therapy. However, it is very difficult to prove all cancer cells are gone. Even though images, like X-rays and MRI’s, and blood tests may not show any signs of cancer, there can be a small amount of cancer cells still left in the body. Because of this, the word “remission” is used more often. This means there are no signs or symptoms of cancer. Patients in remission are followed closely for any signs of cancer returning. Sometimes, more chemotherapy may be given while in remission to prevent the cancer from coming back.

Doctors usually do not consider a patient “cured” until the chance of cancer returning is extremely low. If cancer does return, it usually happens within 5 years of having a remission. Because of this, doctors do not consider a patient cured unless the cancer has not come back within 5 years of remission. The five-year cutoff does not apply to all cancers.

What is a CBC?

A Complete Blood Count (CBC) is a frequently ordered blood test that tells clinicians the status of your: 1) White blood cell count, 2) Hemoglobin, and 3) Platelet count at the time the test was taken.

Common uses:
1) White blood cell count (WBC): is used to determine infection risk, or response to chemotherapy. Certain chemotherapy agents may harm our good infection-fighting cells. Sometimes chemotherapy may need to be delayed to allow these cells to recover.

2) Hemoglobin: is used to determine if someone is anemic. Anytime the hemoglobin is below 12 g/dL, the person is said to be anemic. Red blood cell transfusions, and sometimes iron can be given to restore the hemoglobin level, but anemia treatment should always aim at treating the underlying cause or condition.

3) Platelet count: is used to determine if the risk of bleeding is increased or if a platelet transfusion is required to prevent bleeding. Certain medications that increase bleeding risk, such as: aspirin, certain chemotherapy agents, and blood thinners, may need to be stopped temporarily until the platelet count is within a safe range.

What is a CMP?

A Comprehensive Metabolic Panel (CMP) is a frequently ordered blood test that tells clinicians the status of your: 1) Electrolytes & Acid/Base status2) Kidney function, 3) Liver function, 4) Blood sugar, and 5) Calcium at the time the test was taken. It is commonly used to monitor liver and kidney function when beginning new medications such as chemotherapy. A total of 14 tests are run simultaneously and are shown below.

Electrolytes & Acid/Base status:
1) Sodium, 2) Potassium, 3) Carbon dioxide, 4) Chloride

Kidney Function:
5) BUN (blood urea nitrogen), 6) Serum creatinine (Scr)

Liver Function:
7) AST, 8) ALT, 9) Total bilirubin, 10) Alk Phos, 11) Albumin, 12) Total protein

Blood sugar:
13) Serum glucose

14) Serum calcium

Common Starting Doses

  • Fulvestrant 500 mg intramuscular (I.M.) injection on Days 1 and 15 of Cycle 1, then on Day 1 of subsequent (later) cycles
  • Abemaciclib usual starting dose: 150 mg oral tablet by mouth twice daily

Each cycle is 28 days.

Note: Individual doses may vary based upon your Doctor's recommendation, or drug availability.

A note about side effect percentages

The number you see next to the percent sign (%) means how many people out of 100 are likely to experience this side effect.

For example, if the side effect is reported to occur in 8% of patients, this means that roughly 8 out of 100 people receiving this treatment will experience this side effect.