RUSODX (Ruxolitinib)

Ruxolitinib is a medication used for the treatment of intermediate or high-risk myelofibrosis,a type of myeloproliferative neoplasm that affects the bone marrow; polycythemia vera, when there has been an inadequate response to or intolerance of hydroxyurea; and steroid-refractory acute graft-versus-host disease. Ruxolitinib is a Janus kinase inhibitor.

Myelofibrosis

Kinase inhibitor indicated for treatment of patients with intermediate or high-risk myelofibrosis (MF), including primary MF, post-polycythemia vera MF and post-essential thrombocythemia MF

Initial dose

• Platelet count >200 x10⁹/L: 20 mg PO BID
• Platelet count 100-200 x10⁹/L: 15 mg PO BID
• Platelet count 50 to <100 x10⁹/L: 5 mg PO BID

Insufficient response for patients starting treatment with a platelet count ≥100 X 10^9/L

• If response is insufficient and platelet count and ANC are adequate, dose may be increased in 5 mg BID increments; not to exceed 25 mg PO BID
• Do not increase dose during the first 4 weeks of therapy and no more frequently than q2Weeks

• Consider dose increases in patients who meet all of the following conditions:

  • Failure to achieve a reduction from pretreatment baseline in either palpable spleen length of 50% or a 35% reduction in spleen volume as measured by CT or MRI
  • Platelet count >125 x10⁹/L at 4 weeks and never <100 x10⁹/L
  • ANC levels >0.75 x10⁹/L
  • Long-term maintenance at 5 mg BID has not shown responses and limit continued use at this dose to patients in whom the benefits outweigh the potential risks
  • Discontinue if there is no spleen size reduction or symptom improvement after 6 months of therapy

Insufficient response for patients starting treatment with a platelet count 50 x 10^9/L to <100 x 10^9/L

• If response is insufficient and platelet count and ANC are adequate, doses may be increased by increments of 5 mg qDay to up to 10 mg BID
• Do not increase dose during the first 4 weeks of therapy and no more frequently than q2Weeks

• Consider dose increases in patients who meet all of the following conditions:

  • Platelet count has remained at least 40 x 10⁹/L
  • Platelet count has not fallen by >20% in the prior 4 weeks
  • ANC >1 x 10⁹/L
  • No dose reduction or interruption for an adverse event or hematological toxicity in the prior 4 weeks
• Continuation of treatment for >6 months should be limited to patients in whom the benefits outweigh the potential risks
• Discontinue treatment if there is no spleen size reduction or symptom improvement after 6 months of therapy

Polycythemia Vera

Indicated for polycythemia vera in patients who have had an inadequate response to or are intolerant of hydroxyurea

Initial: 10 mg PO BID

Increasing dose for insufficient response

• If response is insufficient and platelet, hemoglobin, and neutrophil counts are adequate, doses may be increased in 5 mg BID increments to a maximum of 25 mg BID
• Doses should not be increased during the first 4 weeks of therapy and not more frequently than q2Week

• Consider dose increases in patients who meet all of the following criteria:

  • Inadequate efficacy as demonstrated by ≥1 of the following: continued need for phlebotomy, WBC > ULN, platelet count >ULN, palpable spleen that is reduced by <25% from baseline
  • Platelet count ≥140 x10⁹/L
  • Hemoglobin ≥2 g/dL
  • ANC ≥1.5 x 10⁹/L

Acute Graft versus Host Disease

Indicated for treatment of steroid-refractory acute graft-versus-host disease (GVHD)

Initial dose: 5 mg PO BID; may increase to 10 mg BID after at least 3 days if ANC and platelet counts have not decreased by ≥50% compared to baseline

Consider tapering after 6 months in patients with response who have discontinued therapeutic doses of corticosteroids

Tapering dose

• Taper by 1 dose level ~q8Weeks (eg, 10 mg BID to 5 mg BID to 5 mg qDay)
• Patients unable to tolerate 5 mg qDay: Interrupt treatment until clinical and/or laboratory parameters recover
• If acute GVHD signs or symptoms recur during or after taper, consider retreatment

Chronic Graft versus Host Disease

Indicated for treatment of chronic graft-versus-host disease (cGVHD) after failure of 1 or 2 lines of systemic therapy

Initial dose: 10 mg PO BID

Consider tapering after 6 months in patients with response who have discontinued therapeutic doses of corticosteroids

Tapering dose

• Taper by 1 dose level ~q8Weeks (eg, 10 mg BID to 5 mg BID, then from 5 mg BID to 5 mg qDay)
• If acute GVHD signs or symptoms recur during or after taper, consider retreatment