Brand name : Tykerb
Active component : Lapatinib
Strength : 250mg
Manufactured by : GSK pharmaceuticals
Pack : 70 tablets in a container (in a strip 10 tablets)
Classified as : Anti-neoplastic agent
Tykerb tablets are classified as anti-cancer agent, which is orally active drug used for treating breast cancer
Chemically classified as quinazoline with strong anti-cancer effect and the tablet Tykerb is a synthetic oral tablet
Normaly targeted therapy or tyrosine kinase inhibitor drugs are capable of increasing the plasma amino transferase levels which may leads to liver injury, the main ingredient which is used as lapatinib.
Tykerb tablets are classified as;
1. Tyrosine kinase prohibitor
2. Stop the HER2/neu & epidermal growth factor receptor activity
3. Targeted therapy
4. Signal transduction prohibitor
DOSAGE REGIMENS OF Tykerb
In HER2 positive advanced breast cancer:
The usual dose of Tykerb is 1250mg should be given orally as a single dose on day 1 to 21 repeatedly concomitant with Capecitabine 2000mg/m2/day (administer 2 doses relatively 12 hours apart orally ) on day 1 to 14 in continuous 21 day cycle. Sum of 5 tablets of Tykerb should be given at a time as whole.
Patients with hormone receptor positive HER 2 positive advance breast cancer:
The usual dose is 1500mg should be given orally as a single dose by combination with letrozole. The usual dose of letrozole is 2.5mg as a once daily Administer 6 tablets of Tykerb in this condition
Chemically Tykerb is classify as 4-anilinoquinazoline derivative, that evacuate anti-cancer activity by inhibiting intracellular tyrosine kinase domains of EFGR & HER type 2.
The ErbB forced cancer cell production has been prevented by Lapatinib.
This growth factor receptor present on cell surface of cancer mass which may leads to cause cell death.
incomplete and insufficient absorption, the time to peak plasma concentration is 4 hours after intake of drug.
The drug bounds to human plasma protein like albumin & alpha glycoprotein relatively 99%.
Tykerb is a substrate of P-gp & BCRP and go through intensive metabolism by using CYPP3A4 & CYP3A5 with minimum contribution of CYP2C19 & CYP2C8.
Elimination occurs via feces & urine Half life time in 14.2 hours reaches by single dose of Tykerb and multiple dosing reaches in 24 hours.
Reduction in left ventricular ejection fraction : While using Tykerb in patient with LVEF Caution should be taken
The resentment of LVEF should be decreased within first 12 weeks of treatment
Before starting the therapy with Tykerb, patient must be monitor thoroughly if suspected with LVEF or not.
Liver damage : Raising level of AST, ALT or bilirubin may cause liver injury To inhibits this condition, periodic LFT should be control
Diarrhea : Serious diarrhea may cause to dehydration leads death also; if patient do not recover from this severity must stop with this therapy. Interstitial lung disease: Patient should be check with pulmonary symptoms and give supportive measures. On Serious condition, treatment should be discontinue
QT prolongation : Balance ECG periodically Give the patient substituent for this adverse condition Hypokalemia and hypomagnesemia correction should be takes place Cutaneous reactions: Some life threatening reactions may occurs, in this condition therapy should be discontinued
Embryo fetal damage : Tykerb leads to fetal damage and produce some deformities. During therapy Patient should advice not getting pregnant.
Dose alteration :
Left ventricular ejection fraction with grade 2 reduction in patients is given treatment with Tykerb should be discontinued. In this condition, the dose of Tykerb should be started with 1000mg/day in combining with Capecitabine; whereas in combination with letrozole the dose of Tykerb restated with 1250mg/day after 2 weeks, if LVEF turns to normal.
The drug Tykerb are prohibition of CYP3A4, CYP2C8 & P-gp drug transporters; weak inhibitor of CYP3A4. Interaction of Midazolam with Tykerb, increases the exposure of Midazolam Interaction of Paclitaxel will Increase in paclitaxel exposure occurs while concomitant with Tykerb Digoxin interaction with Tykerb then the Serum digoxin concentration should be examined periodically prior starting the concomitant use Drug that induce or inhibit CYP3A4 enzymes: If the interaction of Tykerb tablets with CYP3A4 inducers or inhibitors, alteration of dose is necessary. Interaction of Ketaconazole with Tykerb, the dose reduced to 200mg as two times a day for 7 days. Interaction of Carbamazepine with Tykerb, the dose of carbamazepine at 100mg as a two times a day for 3 days & 200mg for two times a day for 17 days, the exposure of Tykerb reduced to 72%. Concomitant use of Tykerb with P-gp inhibitors causes increasing the concentration of Lapatinib
The doses of Tykerb ranges from 2500mg to 9000mg daily, the duration of therapy should be varied between 1 & 17 days.Symptoms occurred during over dose of Tykerb are;Sore scalp, sinus tachycardia & mucosal inflammation. Patients should be providing with supportive measures.
Severe hepatic impairment in patients, the dose reduced from 1250mg/day to 750mg/day or from 1500mg/day to 1000mg/day. Administer the Tykerb tablet without food as 1 hour before or 2 hours after the uptake of food. Administration of capecitabine along with food or given within 30 minutes after food ingestion.
TYKERB SIDE EFFECTS
Stomatitis, Dyspepsia, Diarrhea, Nausea, Vomiting, Liver toxicity, Interstitial lung disease, Anaphylactic reactions, Stevens Johnson syndrome, Ventricular arrhythmias, QT prolongation, Palmar plantar erythrodysaesthesia, Rash, Dry skin, Mucosal inflammation, Musculoskeletal pain in extremity, Back pain, Dyspnea, Insomnia, Alopecia, Pruritus, Nail disorders, Asthenia, Headache, Epistaxis, Elevation of hemoglobulin, platelets, neutrophils, Increase in AST & ALT, bilirubin, Reduction of left ventricular ejection fraction.
Pregnancy category: D Tykerb should not be recommended during pregnancy condition
The patients who are contraindicated to the component present in Tykerb tablet then hypersentivity reaction occurs
If missed a dose the have it as soon possible or Missed dose should be swapped and continue the regular dosing schedule for avoiding adverse conditions. If missed dose occurs, it should not be resume and continue the next schedule.
Store the drug at 25℃ (77℉). Protect free from moisture, heat or light