Ruxolitinib

Cytostatic · Selective inhibitor of Janus-associated tyrosine kinase JAK1 and JAK2

Indications

Disease-related splenomegaly or symptoms in primary myelofibrosis or in myelofibrosis due to polycythaemia vera or essential thrombocythaemia.

Dosage

Adults: Myelofibrosis: Platelets 50000-100000/mm3: 5 mg twice daily; 100000-200000/mm3: 15 mg twice daily; >200000/mm3: 20 mg twice daily. Titrate according to response and blood counts; starting dose may be increased after 4 wk by max 5 mg twice daily at >2-wk intervals. Max dose 25 mg twice daily. Discontinue if no response after 6 mth, or if 40% increase in baseline spleen length without sustained symptom improvement. Polycythaemia vera: Initially 10 mg twice daily. Max: 25 mg twice daily. Children: Not recommended.

Adverse Effects

Urinary tract infection, herpes zoster, anaemia, thrombocytopenia, neutropenia, bleeding, wt gain, hypercholesterolaemia, dizziness, headache, flatulence, raised LFTs, pneumonia, sepsis, hyperlipidaemia, hypertension, dizziness, headache, constipation, flatulence.

Risk Factor (Pregnancy/Lactation)

Pregnancy: Contraindicated in pregnancy. Lactation: Contraindicated or not recommended. Contraindications: Ensure effective contraception in women of childbearing potential. Active serious infections. Platelets <50000/mm3, ANC <500/mm3. Precautions: Avoid abrupt withdrawal. Platelets <100000/mm3. Perform FBC, including white cell differential, before starting treatment, every 2-4 weeks until dose stabilized (every 1-2 weeks for first 6 weeks in hepatic impairment) and as necessary thereafter. Hepatic or severe renal (CrCl <30 mL/min) impairment. Baseline haemoglobin <10g/dl. Monitor for infections and treat promptly; warn patient of symptoms of herpes zoster. Monitor for new or worsening neurological symptoms suggestive of progressive multifocal leukoencephalopathy; discontinue if suspected. Perform periodic skin examination in patients at risk of skin cancer.

Interactions

Carbamazepine, phenobarbital, phenytoin, rifamycin, CYP3A4 inducers. Protease inhibitors, macrolides, azole antifungals and other CYP3A4 inhibitors, St John's wort, fluconazole and other dual inhibitors of CYP3A4 and CYP2C9. Substrates of P-gp or BCRP. Cytoreductive therapies, haematopoietic growth factors.

Advice to Patient

Take with or without meals. If you miss a dose, skip this dose and take next dose at scheduled time. Do not take double dose. Contact prescriber if there is nausea, vomiting, weakness, chills, aches, fever, fatigue, headache, dizziness, unusual bruising or bleeding, difficulty in breathing, painful skin rash or blisters or if there is no improvement or worsening of condition. Do not take grapefruit juice and products containing grapefruit during therapy. Regular blood tests are required during treatment.

Pharmacokinetics

Absorption: Rapid. Metabolism: Hepatic. Half-life elimination: Ruxolitinib: Approx. 3 hours (hepatic impairment: 4.1 to 5 hours); Ruxolitinib plus metabolites: Approx. 5.8 hours. Time to peak: Within 1 to 2 hours. Excretion: Urine (74%, <1% as unchanged drug), feces (22%, <1% as unchanged drug).

Brands with this active ingredient

• Jakavi
• Mylonib

Compiled by Healify Pharmacy from published drug references. How we compile it →

Always consult a pharmacist or doctor.