Lapatinib Ditosylate (Tykerb)

Lapatinib ditosylate is an oral drug that belongs to the class of tyrosine kinase inhibitors. It is used to treat breast cancer and other solid tumors that overexpress the HER2 (ErbB2) receptor. It works by blocking the activity of two proteins, HER2 and EGFR, that are involved in the growth and survival of cancer cells. Lapatinib ditosylate is marketed by Novartis under the trade names Tykerb and Tyverb in different countries.

Uses of Lapatinib Ditosylate

Lapatinib ditosylate is approved for the following indications:

• It is used in combination with capecitabine (Xeloda), a chemotherapy drug, for the treatment of patients with advanced or metastatic breast cancer whose tumors overexpress HER2 and who have received prior therapy including an anthracycline, a taxane, and trastuzumab (Herceptin).
• It is used in combination with letrozole (Femara), a hormonal therapy drug, for the treatment of postmenopausal women with hormone receptor positive metastatic breast cancer that overexpresses HER2 and for whom hormonal therapy is indicated.
• It is used in combination with trastuzumab for the treatment of patients with HER2-positive metastatic breast cancer who have received prior therapy including trastuzumab and a taxane.

Dose of Lapatinib Ditosylate

The recommended dose of lapatinib ditosylate is 1250 mg (five 250 mg tablets) taken once daily on days 1-21 of a 21-day cycle in combination with capecitabine, 1500 mg/m2 twice daily on days 1-14 of a 21-day cycle. The dose of lapatinib ditosylate may be reduced to 1000 mg or 750 mg once daily in case of severe side effects.

The recommended dose of lapatinib ditosylate is 1500 mg (six 250 mg tablets) taken once daily continuously in combination with letrozole, 2.5 mg once daily continuously. The dose of lapatinib ditosylate may be reduced to 1250 mg, 1000 mg, or 750 mg once daily in case of severe side effects.

The recommended dose of lapatinib ditosylate is 1000 mg (four 250 mg tablets) taken once daily continuously in combination with trastuzumab, 4 mg/kg as an intravenous loading dose followed by 2 mg/kg weekly. The dose of lapatinib ditosylate may be reduced to 750 mg or 500 mg once daily in case of severe side effects.

Lapatinib ditosylate should be taken at least one hour before or one hour after a meal. The tablets should be swallowed whole and not chewed, cut, or crushed.

Side Effects of Lapatinib Ditosylate

Lapatinib ditosylate may cause serious side effects, including:

• Cardiac toxicity: Lapatinib ditosylate may cause heart problems such as decreased heart function, heart failure, or irregular heartbeats. Patients should have their heart function checked before and during treatment with lapatinib ditosylate. Patients should report any symptoms such as shortness of breath, chest pain, palpitations, or swelling of the ankles or legs to their doctor.
• Liver toxicity: Lapatinib ditosylate may cause liver damage that can be fatal. Patients should have their liver function tested before and during treatment with lapatinib ditosylate. Patients should report any symptoms such as jaundice, dark urine, itching, or abdominal pain to their doctor.
• Diarrhea: Lapatinib ditosylate may cause severe diarrhea that can lead to dehydration and electrolyte imbalance. Patients should drink plenty of fluids and take anti-diarrheal medication as prescribed by their doctor. Patients should report any symptoms such as frequent or watery stools, blood in stools, fever, or dizziness to their doctor.
• Rash: Lapatinib ditosylate may cause skin reactions such as rash, redness, itching, dryness, or peeling. Patients should avoid exposure to sunlight or artificial UV rays and use sunscreen and protective clothing. Patients should report any symptoms such as blisters, ulcers, or infection to their doctor.
• Hand-foot syndrome: Lapatinib ditosylate may cause a condition called hand-foot syndrome, which is characterized by redness, swelling, pain, or numbness of the palms of the hands or soles of the feet. Patients should avoid activities that may cause friction or pressure on these areas. Patients should report any symptoms such as blisters, ulcers, or infection to their doctor.

Lapatinib ditosylate may also cause other common side effects, such as:

• Nausea
• Vomiting
• Fatigue
• Headache
• Loss of appetite
• Mouth sores
• Hair loss
• Insomnia
• Cough
• Nosebleeds
• Muscle pain
• Joint pain
• Back pain
• Hot flashes
• Infection

Price of Lapatinib Ditosylate in Different Countries

<

Country	Currency	Price	Reference
Australia	AUD	24.32	PBS Australia
Brazil	BRL	67.76	Consulta Remédios
Canada	CAD	29.83	DrugBank Canada
India	INR	1,000.00	Medindia India
Pakistan	PKR	1,500.00	Dawaai Pakistan
Singapore	SGD	31.77	Novartis Singapore
UK	GBP	18.50	BNF UK
USA	USD	22.00