Abemaciclib

7 DRUG INTERACTIONS CYP3A Inhibitors: Avoid concomitant use of ketoconazole. Reduce the VERZENIO dose with concomitant use of other strong and moderate CYP3A inhibitors. ( 2.2 , 7.1 ) CYP3A Inducers: Avoid concomitant use of strong and moderate CYP3A inducers. ( 7.1 )

7.1 Effect of Other Drugs on VERZENIO CYP3A Inhibitors Strong and moderate CYP3A4 inhibitors increased the exposure of abemaciclib plus its active metabolites to a clinically meaningful extent and may lead to increased toxicity. Ketoconazole Avoid concomitant use of ketoconazole. Ketoconazole is predicted to increase the AUC of abemaciclib by up to 16-fold [see Clinical Pharmacology ( 12.3 )] . Other Strong CYP3A Inhibitors In patients with recommended starting doses of 200 mg twice daily or 150 mg twice daily, reduce the VERZENIO dose to 100 mg twice daily with concomitant use of strong CYP3A inhibitors other than ketoconazole.

In patients who have had a dose reduction to 100 mg twice daily due to adverse reactions, further reduce the VERZENIO dose to 50 mg twice daily with concomitant use of strong CYP3A inhibitors. If a patient taking VERZENIO discontinues a strong CYP3A inhibitor, increase the VERZENIO dose (after 3-5 half-lives of the inhibitor) to the dose that was used before starting the inhibitor. Patients should avoid grapefruit products [see Dosage and Administration ( 2.2 ) and Clinical Pharmacology ( 12.3 )] .

Moderate CYP3A Inhibitors With concomitant use of moderate CYP3A inhibitors, monitor for adverse reactions and consider reducing the VERZENIO dose in 50 mg decrements as demonstrated in Table 1 , if necessary. Strong and Moderate CYP3A Inducers Coadministration of strong or moderate CYP3A inducers decreased the plasma concentrations of abemaciclib plus its active metabolites and may lead to reduced activity. Avoid concomitant use of strong or moderate CYP3A inducers and consider alternative agents [see Clinical Pharmacology ( 12.3 )] .

8.1 Pregnancy Risk Summary Based on findings in animals and its mechanism of action, VERZENIO can cause fetal harm when administered to a pregnant woman [see Clinical Pharmacology ( 12.1 )] . There are no available human data informing the drug-associated risk. Advise pregnant women of the potential risk to a fetus. In animal reproduction studies, administration of abemaciclib during organogenesis was teratogenic and caused decreased fetal weight at maternal exposures that were similar to human clinical exposure based on AUC at the maximum recommended human dose ( see Data). Advise pregnant women of the potential risk to a fetus.

The background risk of major birth defects and miscarriage for the indicated population is unknown. However, the background risk in the U.S. general population of major birth defects is 2 to 4% and of miscarriage is 15 to 20% of clinically recognized pregnancies. Data Animal Data In an embryo-fetal development study, pregnant rats received oral doses of abemaciclib up to 15 mg/kg/day during the period of organogenesis. Doses ≥4 mg/kg/day caused decreased fetal body weights and increased incidence of cardiovascular and skeletal malformations and variations.

These findings included absent innominate artery and aortic arch, malpositioned subclavian artery, unossified sternebra, bipartite ossification of thoracic centrum, and rudimentary or nodulated ribs. At 4 mg/kg/day in rats, the maternal systemic exposures were approximately equal to the human exposure (AUC) at the recommended dose.