Ruxolitinib (Jakavi) — Jakafi: Myelofibrosis & PV Treatment
Ruxolitinib acts as a "fire extinguisher" for an overactive bone marrow. It is a targeted JAK1/JAK2 inhibitor. In conditions like myelofibrosis and polycythemia vera, the JAK signaling pathway gets stuck in the "ON" position, causing uncontrolled blood cell production and massive spleen enlargement.
Ruxolitinib (Jakavi/Jakafi) blocks these chaotic signals. Patients often feel relief quickly: debilitating itching and night sweats disappear, and the enlarged spleen shrinks significantly, relieving pressure on the stomach and reducing pain.
Available as oral tablets, it restores quality of life where traditional chemotherapy often fails.
Indications
- Myelofibrosis: Treatment of disease-related splenomegaly (enlarged spleen) and symptoms (fever, bone pain, weight loss) in adults.
- Polycythemia Vera (PV): For patients who are resistant or intolerant to hydroxyurea.
- Graft-versus-Host Disease (GVHD): For patients developing acute or chronic GVHD after stem cell transplantation, where corticosteroids have failed.
Dosage and administration
Dosage is strictly personalized based on the patient's platelet count.
- Schedule: Tablets are taken twice daily (morning and evening), with or without food.
- Starting Dose: Ranges from 5 mg to 20 mg twice daily.
- CRITICAL WARNING — Withdrawal Syndrome: Never stop taking Ruxolitinib abruptly! Sudden discontinuation can cause a "rebound effect," where symptoms return violently, potentially leading to shock. Dose reduction must be gradual under medical supervision.
- Pregnancy and breastfeeding (harmful to the fetus/infant).
- Hypersensitivity to Ruxolitinib.
- Severe active infections (e.g., tuberculosis, sepsis).
By calming the bone marrow, the drug can sometimes lower blood counts too much.
- Hematologic (Very Common): Anemia (low hemoglobin), thrombocytopenia (bruising/bleeding risk). Dose adjustments or transfusions may be needed.
- Infections: Increased risk of shingles (herpes zoster) and pneumonia.
- Metabolism: High cholesterol and weight gain (often a sign the body is no longer wasting energy fighting the disease).
- Digestive: Flatulence, constipation.
