Medical Pharmacology Practice Questions: Protein Tyrosine Kinase Inhibitors of EGFR: Lapatinib (Tykerb, Tyverb)
Click on the correct answer.
Lapatinib (Tykerb):
May be used in combination with capecitabine in management of breast cancer.
May be used in management of hormone receptor positive metastatic breast cancer overexpressing the HER2 receptor in patients expected to benefit with hormonal treatment (postmenopausal).
Both
Neither
Lapatinib is classified as a dual kinase inhibitor, inhibiting both EGFR and HER2.
True
False
When used in combination with capecitabine (or letrozole) in HER2+ breast cancer patients, these patients would have failed first-line treatment including trastuzumab which targets HER2.
True
Paul's
Lapatinib In conjunction with endocrine treatment may be helpful in reversing or diminishing endocrine resistance that may occur in HER2+ and hormone receptor positive cancer.
Drug absorption is complete following oral administration
Substantial protein binding (greater than 99% to albumin and alpha1-acidicGlycoprotein.
Both
Neither
Concerning lapatinib pharmacodynamic/kinetics:
Lapatinib is mainly metabolized by the liver utilizing the cytochrome P450 drug metabolizing system.
Elimination half-life is about a day
Both
Neither
Lapatinib is mainly excreted in the feces as unchanged drug.
True
False
Lapatinib (as well as other agents in this drug class) is susceptible to drug resistance. This resistance:
May be reflected as "intrinsic resistance" in that nearly 80% of patients will be nonresponders.
Patients who do respond to lapatinib are likely to develop resistance within one year. This type of resistance is termed "acquired resistance."
Both
Neither
In utero exposure to lapatinib may cause injury to the fetus. Women of reproductive potential and male patients with female partners of reproductive potential should use effective contraception during drug treatment and for an additional week following the last lapatinib administration.
True
Numerous adverse reactions are associated with lapatinib in reference a number of different systems e.g. CNS, dermatological, hepatic, etc.
