Usual Adult Dose for Breast Cancer

300 mg orally 2 times a day in combination with trastuzumab and capecitabine until disease progression or unacceptable toxicity

Comments:

• When given in combination with this drug, the recommended dose of capecitabine is 1000 mg/m2 orally 2 times daily taken within 30 minutes after a meal.

Use: This drug, in combination with trastuzumab and capecitabine, is indicated for treatment of adult patients with advanced unresectable or metastatic HER2-positive breast cancer, including patients with brain metastases, who have received one or more prior anti-HER2-based regimens in the metastatic setting

Renal Dose Adjustments

Mild to moderate renal impairment (CrCl 30 to 89 mL/min): No adjustment recommended.
Severe renal impairment (CrCl less than 30 mL/min): Use of this drug in combination with capecitabine and trastuzumab is not recommended.

Liver Dose Adjustments

Mild (Child-Pugh A) or moderate (Child-Pugh B) liver dysfunction: No adjustment recommended.
Severe (Child-Pugh C) liver dysfunction: Reduce dose to 200 mg orally 2 times daily.

Dose Adjustments

Refer to the full prescribing information for trastuzumab and capecitabine for information about dose modifications.

RECOMMENDED DOSE REDUCTION STEPS FOR ADVERSE REACTIONS:

• First dose reduction: 250 mg orally 2 times daily
• Second dose reduction: 200 mg orally 2 times daily
• Third dose reduction: 150 mg orally 2 times daily
• Permanently discontinue this drug in patients unable to tolerate 150 mg orally 2 times daily.

DOSE MODIFICATIONS FOR ADVERSE REACTIONS:
DIARRHEA:

• Grade 3 without antidiarrheal treatment: Initiate or intensify medical management; withhold this drug until recovery to Grade 1 or less; resume at the same dose level.
• Grade 3 with antidiarrheal treatment: Initiate or intensify medical management; withhold this drug until recovery to Grade 1 or less; resume at the next lower dose level.
• Grade 4: Permanently discontinue therapy.

HEPATOTOXICITY:

• Grade 2 bilirubin (greater than 1.5 to 3 times upper limit of normal [ULN]): Withhold therapy until recovery to Grade 1 or less; resume at the same dose level.
• Grade 3 ALT or AST (greater than 5 to 20 x ULN) OR Grade 3 bilirubin (greater than 3 to 10 x ULN): Withhold therapy until recovery to Grade 1 or less; resume at the next lower dose level.
• Grade 4 ALT or AST (greater than 20 x ULN) OR Grade 4 bilirubin (greater than `10 x ULN): Permanently discontinue therapy.
• ALT or AST greater than 3 x ULN AND Bilirubin greater than 2 x ULN: Permanently discontinue therapy.

OTHER ADVERSE REACTIONS:

• Grade 3: Withhold therapy until recovery to Grade 1 or less; resume at the next lower dose level.
• Grade 4: Permanently discontinue therapy.

DOSE MODIFICATIONS FOR CONCOMITANT USE WITH STRONG CYP450 2C8 INHIBITORS:

• Avoid concomitant use of strong CYP450 2C8 inhibitors with this drug.
• If concomitant use with a strong CYP450 2C8 inhibitor cannot be avoided, reduce the dose of this drug to 100 mg orally 2 times daily.
• After discontinuation of the strong CYP450 2C8 inhibitor for 3 elimination half-lives, resume the dose of this drug that was taken prior to initiating the inhibitor.

Precautions

CONTRAINDICATIONS:

• None

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

• Swallow tablets whole; do not chew, crush, or split prior to swallowing.
• Do not ingest tablet if it is broken, cracked, or not otherwise intact.
• Take this drug approximately 12 hours apart and at the same time each day with or without a meal.
• If the patient vomits or misses a dose, take the next dose at its usual scheduled time.

Storage requirements:

• Store at controlled room temperature, 20C to 25C (68F to 77F); excursions permitted from 15C to 30C (59F to 86F).

General:

• Dispense to patient in original container only; store in original container to protect from moisture.
• Replace cap securely each time after opening.
• Do not discard desiccant.
• Discard any unused tablets 3 months after opening the bottle.

Monitoring:

• Liver function: ALT, AST and bilirubin prior to treatment, and then every 3 weeks during treatment and as clinically indicated.

Patient advice:

• Read the US FDA-approved patient labeling (Patient Information and Instructions for Use).

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