Verzenio (abemaciclib)

Verzenio (abemaciclib) is a drug in oral tablet form that attacks tumor cells in patients with HR+/HER2- breast cancer. Specialists prescribe it as part of a combination of drugs that also includes an aromatase inhibitor.

Verzenio is a CDK4 and 6 inhibitor. CDK4 and 6 are proteins that govern how quickly cancer cells need to grow and reproduce, and Verzenio attacks those proteins, making it difficult for the cancer cells to continue growing.

Common side effects include:

• Diarrhea
• Low white blood cell count
• Interstitial lung disease
• Liver toxicity

Pregnant women and nursing mothers should not take Verzenio as it could harm the infant.

• Diarrhea: Instruct patients at the first sign of loose stools to initiate antidiarrheal therapy, increase oral fluids, and notify their healthcare provider.
• Neutropenia: Monitor complete blood counts prior to the start of Verzenio therapy, every 2 weeks for the first 2 months, monthly for the next 2 months, and as clinically indicated.
• Interstitial Lung Disease (ILD)/Pneumonitis: Severe and fatal cases of ILD/pneumonitis have been reported. Monitor for clinical symptoms or radiological changes indicative of ILD/pneumonitis. Permanently discontinue Verzenio in all patients with Grade 3 or 4 ILD or pneumonitis.
• Hepatotoxicity: Increases in serum transaminase levels have been observed. Perform liver function tests (LFTs) before initiating treatment with Verzenio. Monitor LFTs every two weeks for the first two months, monthly for the next 2 months, and as clinically indicated.
• Venous Thromboembolism: Monitor patients for signs and symptoms of thrombosis and pulmonary embolism and treat as medically appropriate.
• Embryo-Fetal Toxicity: Can cause fetal harm. Advise patients of potential risk to a fetus and to use effective contraception

Verzenio tablets are taken orally with or without food.

• Recommended starting dose in combination with fulvestrant or an aromatase inhibitor: 150 mg twice daily.
• Recommended starting dose as monotherapy: 200 mg twice daily.

Dosing interruption and/or dose reductions may be required based on individual safety and tolerability.

• CYP3A Inhibitors: Avoid concomitant use of ketoconazole. Reduce the Verzenio dose with concomitant use of other strong and moderate CYP3A inhibitors.  
• CYP3A Inducers: Avoid concomitant use of strong and moderate CYP3A inducers.

Do not take Verzenio if you are pregnant or may become pregnant. Verzenio can harm developing fetuses. Do not breastfeed while taking Verzenio, as the drug is excreted in breast milk and could harm the infant.