IMATIS (IMATINIB) 100MG TABLETS 120`S

Imanix contains imatinib mesilate, the first molecularly targeted anti-cancer therapy. It selectively inhibits the BCR-ABL tyrosine kinase (the pathogenic kinase in CML), as well as KIT (CD117) and PDGFR kinases, making it active across a range of malignancies driven by these enzymes.

The 100mg strength is used when:

•       Paediatric dosing: children require weight- and body surface area (BSA)-based dosing (340 mg/m²/day) which rarely corresponds to a 400mg unit dose. The 100mg tablet allows precise BSA-calculated dosing.

•       Adult dose reduction: when the standard 400mg dose causes intolerable side effects and a lower dose (e.g. 300mg or 200mg) is clinically appropriate.

•       Flexible dose titration: escalating beyond 400mg (e.g. to 600mg or 800mg) requires adding 100mg or 200mg increments.

Indications are identical to Imanix 400mg: CML (children and adults), Ph+ ALL, GIST, and other imatinib-sensitive malignancies driven by BCR-ABL, KIT, or PDGFR.

Paediatric CML:

340 mg/m²/day, given as a single daily dose or divided into two doses if total dose ≥340mg. Maximum 600mg/day. Body surface area must be calculated at each dose review.

Adult dose reduction or titration:

As directed by the haematologist/oncologist based on toxicity profile and response.

Administration: take with food and a large glass of water. Swallow whole, or dissolve in water/apple juice for patients who cannot swallow tablets.

•       Growth monitoring: long-term imatinib in children may cause growth retardation. Monitor height and weight at every clinic visit throughout treatment. Pubertal development should also be assessed annually.

•       Bone health: bone metabolism effects have been reported in children on long-term imatinib. Monitor for bone pain and consider DXA if clinically indicated.

•       Dissolving tablets: dissolve in water or apple juice if the child cannot swallow. Stir thoroughly until completely dissolved and give immediately.

•       Known hypersensitivity to imatinib or any excipient

•       Pregnancy and breastfeeding — imatinib is teratogenic. Effective contraception is required during treatment and for 30 days after the last dose.

•       Moderate-severe hepatic impairment: dose reduction to 300mg required; monitor LFTs closely

•       Cardiac disease: imatinib is cardiotoxic — can cause left ventricular dysfunction; baseline cardiac assessment and regular monitoring in at-risk patients

•       Strong CYP3A4 inhibitors (ketoconazole, clarithromycin, itraconazole): increase imatinib plasma levels significantly — monitor for toxicity

•       CYP3A4 inducers (rifampicin, phenytoin, carbamazepine, St. John's Wort): markedly reduce imatinib efficacy — avoid; consider dose increase if unavoidable

•       Warfarin: imatinib inhibits CYP2C9, increasing warfarin effect. Substitute LMWH for warfarin wherever possible in patients on imatinib. If warfarin is essential, monitor INR very frequently.

•       Simvastatin and other CYP3A4 substrates: imatinib raises their levels — consider statin switch to pravastatin or rosuvastatin (not CYP3A4-dependent)

•       Paracetamol at high doses: increased hepatotoxicity risk in combination — limit paracetamol dose

Q: Why is this a 100mg tablet and not the standard 400mg?

The 100mg strength is used for children, whose dose is calculated based on body size (weight and height), and for adults who need lower doses due to side effects. It allows much more precise dosing compared to the 400mg tablet.

Q: Does imatinib affect a child's growth?

Long-term use of imatinib in children may slow growth in some cases. Your paediatric oncologist will monitor your child's height and weight at each visit throughout treatment and assess growth trajectory over time.

Q: Is it the same medicine as the 400mg tablets?

Yes — the same active ingredient (imatinib mesilate) at a different strength. The 100mg strength simply allows smaller or more precise doses. The mechanism, side effects, and monitoring requirements are the same.