GLIVEC 100MG

Description

Glivec 100mg is used as monotherapy, or it may combine with some other medicine in the conditions of certain types of cancer or bone marrow disorders. PDG-derived tyrosine kinase that are expressed in gastrointestinal stromal tumor.

Glivec 100mg indicated for

Glivec 100mg tablet is an anti-neoplastic medicine which is used in the treatment of;

• Advanced myelogenous leukemia (CML),
• Gastrointestinal stromal tumors (GISTs) and several malignancies
• Myelodysplastic/myeloproliferative disease
• Chronic Myeloid Leukemia
• Dermatofibrosarcoma protuberans
• Mastocytosis

How Glivec 100mg tablets work

Glivec contains an active component known as Imatinib mesylate; it is an inhibitor of certain tyrosine kinase enzymes.

Glivec prohibits BCR-ABL tyrosine

Glivec obstruct the multiplication and promote the apoptosis in BCR-ABL positive cells in addition to fresh leukemia cells from Philadelphia chromosome positive CML

Glivec also inhibits tumor growth of BCR-ABL transacted murine myeloid cells along other BCR-ABL positive leukemia CML in blast crisis

Glivec inhibits receptor tyrosine kinase for platelet-derived growth factor (PDGF), stem cell factor (SCF) and PDGF and SCF mediated cellular events get prohibited.

• Glivec a 2-phenylaminopyrimidine analog, it acts as a prohibitor of tyrosine kinase enzyme.
• In malignancy conditions, Philadelphia chromosome leads to fusing of protein with BCR (breakpoint cluster region). Glivec used to reduced Bcr-Abl activity

Absorption

it is absorbed within 2-4 hours and bioavailability of Glivec 100mg tablets is about 98%.

Distribution

Glivec 100mg tablet has Human plasma protein bound almost range of 95%.

Metabolism

Glivec 100mg tablet Active metabolite is N-demethylated piperazine derivative. The enzyme which is responsible for metabolism of Glivec 100mg tablet is CYP3A4.

Excretion

The elimination of Glivec400mg through feces                                                                                                                  

The total drug excreted through feces 81% and drug through urine 13% with 7 days

The half life time of Glivec and active metabolite N-dimethyl derivative are around 18 and 40 hours respectively

Dosage and administration

The usual dose of tablet Glivec is 400mg or 600mg as a single dose. Whereas 800mg given by dividing the dose into two as 400mg twice daily.

Glivec tablets should be taken with food

The usual dose for following conditions;

Chronic myeloid leukemia

Chronic phase: In newly diagnosed patients, the dose of Glivec 100mg tablet is 400mg should be orally taken as a single dose.

If the failure of chronic phase of the treatment with interferon alpha therapy; dose is raised to 600mg per day.

Quick phase: 600mg PO q Day; dose variation to 400mg PO as twice in a day  if there is no serious  adverse drug reaction or non-leukemia associated neutropenia or thrombocytopenia.

Gastrointestinal stromal tumors

The prescribed dose of the tablet Glivec 100mg is 400mg should be taken orally as a twice daily

Hyperesinophillic syndrome

In this condition, recommended dose is 400mg PO q Day

Acute lymphoblastic leukemia

In adults, the prescribed dose is 600mg should be taken orally as a single dose.

Myelodysplastic/Myeloproliferative diseases

The usual dose is 400mg PO q Day

Dermatofibrosarcoma protuberans

Recommended dose is 400mg PO q12hr

In pediatric

Chronic myeloid leukemia

<1 year: the safety and efficacy of the drug has not been established

≥1 year: 340mg/m²/day PO; should not be exceed 600mg/day

Acute lymphoblastic leukemia

Patients<1 year: the safety and efficacy of the drug has not been established

Patients≥1 year: 340mg/m²/day PO; should not be exceed 600mg/day

Glivec 100mg tablet causes some side effects

Side effects are common in patients administrating Glivec 100mg-30%

• Nausea and vomiting
• Edema (swelling of the face, feet, hands)
• Muscle cramps and bone pain
• Diarrhea
• Haemorrhage
• Skin rash
• Fever
• Decreased blood counts

Less common side effects occur in patients administrating 10-29%

• Headache
• Fatigue
• Joint pain
• Indigestion (see heartburn)
• Abdominal pain
• Cough
• Shortness of breath
• Poor appetite
• Constipation
• Night sweats (see skin reactions)
• Nose bleeds (see bleeding problems)
• Weakness
• Affect ability to conceive or father a child

Drug – drug interaction

Warfarin is metabolized by CYP2C9 & CYP2A4, so patients who are taking anticoagulation therapy with Glivec, should take low molecular weight or standard heparin in reverse of warfarin.

Drug which inhibits the CYP3A4 activity may have chance to reduce metabolism and elevates the plasma concentration of Glivec frequently.

Concomitant use of St. John’s wort with Glivec causes decreasing AUC of Glivec to 30%. To avoid this problem, the dosage of Glivec increases up to 1200mg /day (600mg as two times a day).

While interaction of Glivec with strong inducers of CYP3A4, the dose of Glivec 100mg increased to 50%. If used with CYP3A4 strong inducers the AUC of Glivec 100mg decreases to 73%.

Combination of Glivec 100mg with strong CYP3A4 inhibitors; increase the risk of Glivec. Avoid these co administrations like Glivec 100mg with ketoconazole, itraconazole, clarithromycin, atazanavir, indinavir, ritonavir, voriconazole etc.

Interaction of Glivec 100mg with CYP3A4 substrates like alfentanil, cyclosporine, ergotamine, fentanyl, sirolimus or Tacrolimus causes low therapeutic effects. Glivec elevates the plasma concentration of CYP3A4 metabolized drugs like lipid lowering, calcium channel blockers etc.

Contraindication

Hypersensitive reaction to Glivec 100mg and other excipients presents in Glivec 100mg tablets.

Precaution

Avoid combination of strong CYP3A4 inducers

If anticoagulation is necessary, use LMW or standard heparin instead of warfarin

Gastrointestinal disorders: To avoid this problem, Glivec should be taken with food and large glass of water.

Hyperesinophillic cardiac toxicity

Dermatological toxicities

Hypothyroidism: Levothyroxine replacement therapy recommended; TSH level of the patients should be monitored periodically.  

Fluid retention and edema: The major damage of Glivec is fluid collection which may causes edema majorly superficial edema has been reported. To overcome these problem patients may frequently monitor for manifestation of fluid retention.

Hematological toxicity: Neutropenia, thrombocytopenia, anemia are the major blood related problems. To avoid these conditions, monitor the patients periodically with counting blood cell counts weekly for one month, two weeks for two months.

Serious congestive heart failure and left ventricular dysfunction: Patients who have cardiac problems should be monitored frequently.

Hepatotoxicity: Liver function test should be taken periodically to overcome these problems.

Pregnancy

Pregnancy category: D

Glivec 100mg will cause fetal harm when given to pregnant women

No clinical studies regarding use of drug in pregnant women

Lactations

Glivec 100mg should not recommended to pregnant and breast-feeding mothers, it can able to cause fetal malformations and cause fetal harm

The metabolites excreted in human milk.

Storage condition

Glivec 100mg tablet container should be stored in cool and dry place

It should be kept away from moisture, heat and light

Missed dose

If patient missed to take Glivec 100mg tablet, patient should have administered within a time. Otherwise, tablet should be discontinued and follow the next drug schedule.

Consult the doctor as soon as possible.