Lapatinib is indicated for the treatment of adult patients with breast cancer, whose tumours overexpress HER2 (ErbB2):
For this indication, competent medicine agencies globally authorize below treatments:
Oral
1,000 - 1,500 mg
From 1,000 To 1,500 mg once every day
The recommended dose of lapatinib is 1250 mg once daily continuously.
The recommended dose of capecitabine is 2000 mg/m²/day taken in 2 doses 12 hours apart on days 1-14 in a 21 day cycle. Capecitabine should be taken with food or within 30 minutes after food.
The recommended dose of lapatinib is 1000 mg once daily continuously.
The recommended dose of trastuzumab is 4 mg/kg administered as an intravenous loading dose, followed by 2 mg/kg intravenous weekly.
The recommended dose of lapatinib is 1500 mg once daily continuously.
Lapatinib should be discontinued in patients with symptoms associated with decreased left ventricular ejection fraction (LVEF) that are National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) grade 3 or greater or if their LVEF drops below the institutions lower limit of normal. Lapatinib may be restarted at a reduced dose (750 mg/day when administered with trastuzumab, 1000 mg/day when administered with capecitabine or 1250 mg/day when administered with an aromatase inhibitor) after a minimum of 2 weeks and if the LVEF recovers to normal and the patient is asymptomatic.
Lapatinib should be discontinued in patients who experience pulmonary symptoms which are NCI CTCAE grade 3 or greater.
Lapatinib dosing should be interrupted in patients with diarrhoea which is NCI CTCAE grade 3 or grade 1 or 2 with complicating features (moderate to severe abdominal cramping, nausea or vomiting greater than or equal to NCI CTCAE grade 2, decreased performance status, fever, sepsis, neutropenia, frank bleeding or dehydration). Lapatinib may be reintroduced at a lower dose (reduced from 1000 mg/day to 750 mg/day, from 1250 mg/day to 1000 mg/day or from 1500 mg/day to 1250 mg/day) when diarrhoea resolves to grade 1 or less. Lapatinib dosing should be permanently discontinued in patients with diarrhoea which is NCI CTCAE grade 4.
Discontinuation or interruption of dosing with lapatinib may be considered when a patient develops toxicity greater than or equal to grade 2 on the NCI CTCAE. Dosing can be restarted, when the toxicity improves to grade 1 or less, at 1000 mg/day when administered with trastuzumab, 1250 mg/day when administered with capecitabine or 1500 mg/day when administered with an aromatase inhibitor. If the toxicity recurs, then lapatinib should be restarted at a lower dose (750 mg/day when administered with trastuzumab, 1000 mg/day when administered with capecitabine or 1250 mg/day when administered with an aromatase inhibitor).
Lapatinib should be taken either at least one hour before, or at least one hour after food. To minimise variability in the individual patient, administration of lapatinib should be standardised in relation to food intake, for example always to be taken one hour before a meal.
The bioavailability of lapatinib is increased up to about 4 times by food, depending on e.g. the fat content in the meal. Furthermore, depending on type of food the bioavailability is approximately 2-3 times higher when lapatinib is taken 1 hour after food compared with 1 hour before the first meal of the day.