Lapatinib

Lapatinib is a 4-anilinoquinazoline kinase inhibitor of the intracellular tyrosine kinase domains of both Epidermal Growth Factor Receptor (EGFR [ErbB1]) and of Human Epidermal Receptor Type 2 (HER2 [ErbB2]) receptors (estimated Ki app values of 3nM and 13nM, respectively) with a dissociation half-life of greater than or equal to 300 minutes. Lapatinib inhibits ErbB-driven tumor cell growth in vitro and in various animal models.

• Lapatinib tablets are indicated in combination with: capecitabine for the treatment of patients with advanced or metastatic breast cancer whose tumors overexpress human epidermal growth factor receptor 2 (HER2) and who have received prior therapy, including an anthracycline, a taxane, and trastuzumab. Limitations of Use : Patients should have disease progression on trastuzumab prior to initiation of treatment with lapatinib tablets in combination with capecitabine.ICD-10: C50.919

• Lapatinib tablets are contraindicated in patients with known severe hypersensitivity (e.g., anaphylaxis) to this product or any of its components. Known severe hypersensitivity (e.g., anaphylaxis) to this product or any of its components.contraindicated

The recommended dosage of lapatinib tablets for advanced or metastatic breast cancer is 1,250 mg (5 tablets) given orally once daily on Days 1 to 21 continuously in combination with capecitabine 2,000 mg/m 2 /day (administered orally in 2 doses approximately 12 hours apart) on Days 1 to 14 in a repeating 21-day cycle. ( 2.1 ) The recommended dose of lapatinib tablets for hormone receptor-positive, HER2-positive metastatic breast cancer is 1,500 mg (6 tablets) given orally once daily continuously in combination with letrozole. When lapatinib tablets are coadministered with letrozole, the recommended dose of letrozole is 2.5 mg once daily. ( 2.1 ) Lapatinib tablets should be taken at least one hour before or one hour after a meal. However, capecitabine should be taken with food or within 30 minutes after food. ( 2.1 ) Lapatinib tablets should be taken once daily. Do not divide daily doses of lapatinib tablets. ( 2.1 , 12.3 ) Modify dose for cardiac and other toxicities, severe hepatic impairment, diarrhea, and CYP3A4 drug interactions. ( 2.2 ) 2.1 Recommended Dosing HER2-Positive Metastatic Breast Cancer : The recommended dose of lapatinib tablets is 1,250 mg given orally once daily on Days 1 to 21 continuously in combination with capecitabine 2,000 mg/m 2 /day (administered orally in 2 doses approximately 12 hours apart) on Days 1 to 14 in a repeating 21-day cycle. Lapatinib tablets should be taken at least one hour before or one hour after a meal.

Decreases in left ventricular ejection fraction (LVEF) have been reported. Confirm normal LVEF before starting lapatinib and continue evaluations during treatment. ( 5.1 ) Lapatinib has been associated with hepatotoxicity. Monitor liver function tests before initiation of treatment, every 4 to 6 weeks during treatment, and as clinically indicated. Discontinue and do not restart lapatinib if patients experience severe changes in liver function tests. ( 5.2 ) Dose reduction in patients with severe hepatic impairment should be considered. ( 2.2 , 5.3 , 8.7 ) Diarrhea, including severe diarrhea, has been reported during treatment. Manage with antidiarrheal agents, and replace fluids and electrolytes if severe. ( 5.4 ) Lapatinib has been associated with interstitial lung disease and pneumonitis. Discontinue lapatinib if patients experience severe pulmonary symptoms. ( 5.5 ) Lapatinib may prolong the QT interval in some patients. Consider electrocardiogram (ECG) and electrolyte monitoring. ( 5.6, 12.2 ) Severe cutaneous reactions have been reported. Discontinue lapatinib if life-threatening reactions are suspected. ( 5.7 ) Lapatinib can cause fetal harm. Advise patients of the potential risk to the fetus and to use effective contraception. ( 5.8 , 8.1 , 8.3 ) 5.1 Decreased Left Ventricular Ejection Fraction Lapatinib has been reported to decrease LVEF [see Adverse Reactions ( 6.1 )] . In clinical trials, the majority (greater than 57%) of LVEF decreases occurred within the first 12 weeks of treatment; however, data on long-term exposure are limited.

The most common (greater than 20%) adverse reactions during treatment with lapatinib plus capecitabine were diarrhea, palmar-plantar erythrodysesthesia, nausea, rash, vomiting, and fatigue. The most common (greater than or equal to 20%) adverse reactions during treatment with lapatinib plus letrozole were diarrhea, rash, nausea, and fatigue. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact AvKARE at 1-855-361-3993 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. HER2-Positive Metastatic Breast Cancer : The safety of lapatinib has been evaluated in more than 12,000 patients in clinical trials. The efficacy and safety of lapatinib in combination with capecitabine in breast cancer was evaluated in 198 patients in a randomized, Phase 3 trial [see Clinical Studies ( 14.1 )] . Adverse reactions, which occurred in at least 10% of patients in either treatment arm and were higher in the combination arm, are shown in Table 1. The most common adverse reactions (greater than 20%) during therapy with lapatinib plus capecitabine were gastrointestinal (diarrhea, nausea, and vomiting), dermatologic (palmar-plantar erythrodysesthesia and rash), and fatigue. Diarrhea was the most common adverse reaction resulting in discontinuation of study medication.

Lactation: Advise not to breastfeed. ( 8.2 ) Females and Males of Reproductive Potential: Verify the pregnancy status of females prior to initiation of lapatinib tablets. ( 8.3 ) 8.1 Pregnancy Risk Summary Based on findings in animal studies and its mechanism of action, lapatinib can cause fetal harm when administered to a pregnant woman [see Clinical Pharmacology ( 12.1 )] . There are no available human data to inform of the drug-associated risks. In an animal reproduction study, administration of lapatinib to pregnant rats during organogenesis and through lactation led to death of offspring within the first 4 days after birth at maternal exposures that were ≥ 3.3 times the human clinical exposure based on AUC following 1,250 mg dose of lapatinib plus capecitabine. When administered to pregnant animals during the period of organogenesis, lapatinib caused fetal anomalies (rats) or abortions (rabbits) at maternally toxic doses (see Data) . Advise pregnant women and females of reproductive potential of the potential risk to the fetus. The background risk of major birth defects and miscarriage for the indicated population is unknown; however, in the U.S. general population, the estimated background risk of major birth defects is 2% to 4% and of miscarriage is 15% to 20% of clinically recognized pregnancies.

Metabolism

Absorption : Absorption following oral administration of lapatinib is incomplete and variable. Serum concentrations appear after a median lag time of 0.25 hours (range 0 to 1.5 hours).

There is no known antidote for overdoses of lapatinib. The maximum oral doses of lapatinib that have been administered in clinical trials are 1,800 mg once daily. More frequent ingestion of lapatinib could result in serum concentrations exceeding those observed in clinical trials and could result in increased toxicity. Therefore, missed doses should not be replaced and dosing should resume with the next scheduled daily dose. Asymptomatic and symptomatic cases of overdose have been reported. The doses ranged from 2,500 to 9,000 mg daily and where reported, the duration varied between 1 and 17 days. Symptoms observed include lapatinib-associated events [see Adverse Reactions (6.1)] and in some cases sore scalp, sinus tachycardia (with otherwise normal ECG), and/or mucosal inflammation. Because lapatinib is not significantly renally excreted and is highly bound to plasma proteins, hemodialysis would not be expected to be an effective method to enhance the elimination of lapatinib. Treatment of overdose with lapatinib should consist of general supportive measures.

• Mar 13, 2007NDANDA022059Novartis
• Sep 29, 2020ANDAANDA203007Natco Pharma Ltd
• Aug 16, 2024ANDAANDA217968Teva Pharms Usa Inc

1. 1Diarrhoea4,17127%
2. 2Nausea1,61310%
3. 3Death1,4529.4%
4. 4Fatigue1,3048.5%
5. 5Vomiting1,2077.8%
6. 6Rash1,0606.9%
7. 7Disease Progression9996.5%
8. 8Palmar-plantar Erythrodysaesthesia Syndrome9216.0%
9. 9Asthenia6043.9%
10. 10Drug Ineffective5603.6%
11. 11Dyspnoea5603.6%
12. 12Malignant Neoplasm Progression5593.6%
13. 13Pyrexia5273.4%
14. 14Dehydration5243.4%
15. 15Decreased Appetite5193.4%

Recent PubMed references pinned to Lapatinib as a MeSH major topic. Citations link to pubmed.ncbi.nlm.nih.gov.

• Safety and efficacy of lapatinib, binimetinib, and vinorelbine for RAS mutant metastatic colorectal cancer: results of the RASTRIC Phase I/II trial.
  British journal of cancer · 2026 · Huismans MA, Gort EH, van der Heijden LT, et al.
  PMID 41946829DOI 10.1038/s41416-026-03398-x
• Structure-based drug repurposing reveals ponatinib and lapatinib as stable inhibitors of Aurora kinase B: Mechanistic insights from high-resolution molecular dynamics and free-energy analyses.
  Computational biology and chemistry · 2026 · Hasan GM, Thiyagarajan R, Mohammad T, et al.
  PMID 41905170DOI 10.1016/j.compbiolchem.2026.109034
• Supersaturated SNEDDS for enhancing the bioavailability of lapatinib ditosylate: A mechanistic approach to bridge the solubilization-absorption gap.
  European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V · 2026 · Singh N, Pal A, Kumar A, et al.
  PMID 41866001DOI 10.1016/j.ejpb.2026.115062
• Nuclear-Targeted Boron-Lapatinib Hybrid for Enhanced Boron Neutron Capture Therapy in Advanced Thyroid Carcinoma.
  ChemMedChem · 2026 · Couto M, Buschittari M, Carpano M, et al.
  PMID 41838928DOI 10.1002/cmdc.202501074
• Tumor-Intrinsic PD-1 Regulatory Network Drives Lapatinib Resistance in HER2⁺ Breast Cancer: An Integrative Bioinformatics Analysis.
  Asian Pacific journal of cancer prevention : APJCP · 2026 · Alhallaq AS, Sultan NS
  PMID 41660919DOI 10.31557/APJCP.2026.27.2.613
• Innovative Microwave-Assisted Fabrication of N,S-Doped Carbon Quantum Dots as Fluorescent Nanosensors for the Sensitive Monitoring of Lapatinib in Plasma and Water Samples: A Holistic Evaluation of Greenness, Efficiency, and Novelty.
  Luminescence : the journal of biological and chemical luminescence · 2026 · Alrashidi AA, Magdy G, Radwan AS, et al.
  PMID 41562616DOI 10.1002/bio.70427
• The Analytical Method Development for Genotoxic Impurities of Lapatinib Ditosylate Monohydrate by Reversed Phase High-Performance Liquid Chromatography.
  Journal of chromatographic science · 2025 · Shah S, Savalia V, Vekariya H, et al.
  PMID 41396825DOI 10.1093/chromsci/bmaf061
• Cytotoxic Effects of Sorafenib, Lapatinib, and Bevacizumab, Alone and in Combination, on Medullary Thyroid Carcinoma Cells.
  Current oncology (Toronto, Ont.) · 2025 · Altun G, Yönem Ö
  PMID 41294669DOI 10.3390/curroncol32110607

The 10 most recently updated of 322 ClinicalTrials.gov registrations naming Lapatinib as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• Dabrafenib and Lapatinib in Treating Patients With Refractory Thyroid Cancer That Cannot Be Removed by Surgery
  Active not recruiting · Phase 1 · Interventional · 23 enrolled · National Cancer Institute (NCI)
  NCT01947023updated 2026-05-14
• Pilot Study of [68Ga]Ga-ABY-025 Imaging in Patients Undergoing Treatment With HER2-targeted Therapy
  Recruiting · Early phase 1 · Interventional · 30 enrolled · Vanderbilt-Ingram Cancer Center
  NCT06828588updated 2026-05-08
• Molecular Profiling of Advanced Soft-tissue Sarcomas
  Completed · Phase 3 · Interventional · 603 enrolled · Institut National de la Santé Et de la Recherche Médicale, France
  NCT03784014updated 2026-04-29
• Safety and Efficacy of BKM120 and Lapatinib in HER2+/PI3K-activated, Trastuzumab-resistant Advanced Breast Cancer
  Terminated · Phase 1 · Phase 2 · Interventional · 24 enrolled · Institut Paoli-Calmettes
  NCT01589861updated 2026-04-21
• Multimodality Risk Adapted Tx Including Induction Chemo for SCCHN Amenable to Transoral Surgery
  Completed · Phase 2 · Interventional · 40 enrolled · UNC Lineberger Comprehensive Cancer Center
  NCT01612351updated 2026-03-17
• DS-8201a in Pre-treated HER2 Breast Cancer That Cannot be Surgically Removed or Has Spread [DESTINY-Breast02]
  Completed · Phase 3 · Interventional · 608 enrolled · Daiichi Sankyo
  NCT03523585updated 2026-02-27
• Effectiveness, Safety, and Tolerability of Anti-HER2 Drugs as Targeted Therapy for Egyptian Patients With ERBB2-Positive Breast Cancer
  Completed · Observational · 80 enrolled · Deraya University
  NCT07416409updated 2026-02-18
• HKI-272 for HER2-Positive Breast Cancer and Brain Metastases
  Completed · Phase 2 · Interventional · 140 enrolled · Dana-Farber Cancer Institute
  NCT01494662updated 2026-01-23
• Pilot Study of Veliparib (ABT-888) and Lapatinib (Tykerb) in Patients With Metastatic, Triple Negative Breast Cancer
  Completed · Interventional · 20 enrolled · University of Alabama at Birmingham
  NCT02158507updated 2026-01-22
• A Randomized Phase II Trial Comparing Therapy Based on Tumor Molecular Profiling Versus Conventional Therapy in Patients With Refractory Cancer
  Completed · Phase 2 · Interventional · 742 enrolled · Institut Curie
  NCT01771458updated 2025-11-24

CPIC-curated drug–gene pairs for Lapatinib. Levels describe the strength of curated evidence and guideline status — never a recommendation to test or to adjust therapy.

• HLA-DQA1CPIC C (provisional)ClinPGx 3FDA label: Informative PGx
• HLA-DRB1CPIC B/C (provisional)ClinPGx 3FDA label: Informative PGx

Frequently asked questions

How does Lapatinib work?

Lapatinib is a 4-anilinoquinazoline kinase inhibitor of the intracellular tyrosine kinase domains of both Epidermal Growth Factor Receptor (EGFR [ErbB1]) and of Human Epidermal Receptor Type 2 (HER2 [ErbB2]) receptors (estimated Ki app values of 3nM and 13nM, respectively) with a dissociation half-life of greater than or equal to 300 minutes. Lapatinib inhibits ErbB-driven tumor cell growth in vitro and in various animal models.

What is Lapatinib used for?

According to FDA labeling, Lapatinib carries indications including: Lapatinib tablets are indicated in combination with: capecitabine for the treatment of patients with advanced or metastatic breast cancer whose tumors overexpress human epidermal growth factor receptor 2 (HER2) and who have received prior therapy, including an anthracycline, a taxane, and trastuzumab. Limitations of Use : Patients should have disease progression on trastuzumab prior to initiation of treatment with lapatinib tablets in combination with capecitabine.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Lapatinib?

Lapatinib is classified as Human epidermal growth factor receptor 2 (HER2) tyrosine kinase inhibitors, Kinase Inhibitor, HER2/Neu/cerbB2 Antagonists, Protein Kinase Inhibitors, Cellular Proliferation Alteration.

What are the brand names for Lapatinib?

Lapatinib is marketed under brand names including Tykerb.

What are the contraindications for Lapatinib?

Lapatinib labeling lists contraindications including: Lapatinib tablets are contraindicated in patients with known severe hypersensitivity (e.g., anaphylaxis) to this product or any of its components. Known severe hypersensitivity (e.g., anaphylaxis) to this product or any of its components.. Always consult the full prescribing information and a clinician.