What are the side effects of Jakafi (ruxolitinib)?

Side Effects of Jakafi (Ruxolitinib)

Jakafi (ruxolitinib) has several significant side effects including thrombocytopenia, anemia, increased risk of infections, and potential withdrawal syndrome if discontinued abruptly. 1

Common Hematologic Side Effects

• Thrombocytopenia (low platelet count) is a main adverse event and may require dose adjustments based on platelet levels 1
• Anemia (low red blood cell count) is frequently observed, especially at the beginning of therapy, and may require blood transfusions 1
• Neutropenia (low white blood cell count) can occur and should be monitored through regular complete blood counts 1
• Lymphopenia may develop during treatment 1

Infection Risk

• Increased risk of infections including bacterial, fungal, and viral infections due to JAK inhibition affecting immune function 1
• Tuberculosis screening is recommended as reactivation can occur during treatment 1
• Herpes zoster (shingles) risk is elevated in patients taking ruxolitinib 1
• Hepatitis B reactivation can occur in patients with chronic HBV infection 1
• Opportunistic infections may develop, requiring careful monitoring for signs and symptoms 1

Metabolic and Other Side Effects

• Lipid abnormalities including elevated cholesterol and triglycerides require monitoring 8-12 weeks after starting treatment 1
• Elevated CPK (creatine phosphokinase) levels may occur but are usually not associated with clinical symptoms 1
• Mild elevations in creatinine have been reported but generally don't lead to renal failure 1

Serious Adverse Events

• Withdrawal syndrome can occur with sudden discontinuation of ruxolitinib, presenting as a shock-like syndrome due to reactivation of inflammatory cytokines 1
• Increased risk of certain cancers, particularly lymphoma and skin cancers 2
• Major adverse cardiovascular events including heart attack, stroke, or death, especially in patients over 50 with cardiovascular risk factors 2
• Venous thromboembolism including deep vein thrombosis (DVT) and pulmonary embolism (PE) 2

Special Considerations

• Dose modifications are required for patients with renal or hepatic impairment 1
• Tapering is recommended when discontinuing ruxolitinib rather than abrupt cessation to avoid withdrawal syndrome 1
• Regular monitoring of blood counts is necessary every 2-4 weeks until doses are stabilized 1
• Skin examinations should be performed periodically due to increased risk of skin cancers 2

Management of Side Effects

• Thrombocytopenia management: Dose reduction, interruption, or platelet transfusions may be necessary 1
• Anemia management: Blood transfusions and/or dose modifications may be required 1
• Infection management: Prompt treatment of infections and temporary discontinuation of ruxolitinib may be necessary during serious infections 1
• Lipid abnormalities: Treat according to clinical guidelines for hyperlipidemia 1

Precautions

• Patients with active infections should not start ruxolitinib until the infection is controlled 2
• Patients with tuberculosis risk factors should be tested for latent infection before starting treatment 1
• Patients with hepatitis B should be monitored for viral load increases 1
• Patients with renal or hepatic impairment require dose adjustments 1

Remember that the benefits of ruxolitinib in treating myelofibrosis, polycythemia vera, or other conditions must be weighed against these potential side effects, with appropriate monitoring and management strategies in place 1, 3.