• Assess for signs of DVT and PE (dyspnea, chest pain, arm or leg swelling) periodically during therapy; risk is greater when lenalidomide is administered with dexamethasone. Venous thromboembolism prophylaxis is recommended in patients receiving lenalidomide; prophylaxis regimen should be based on assessment of the patient’s underlying risks.

• Assess for SJS, DRESS, and TEN. If Grade 2–3 rash occurs, consider holding or discontinuing therapy. If SJS, DRESS, or TEN is suspected or Grade 4 rash occurs, permanently discontinue lenalidomide.
• Monitor for signs and symptoms of tumor flare reaction (tender lymph node swelling, low-grade fever, pain rash); may mimic mantle cell lymphoma progression. If Grade 1–2 tumor flare reaction occurs, may continue lenalidomide without interruption or modification, at health care provider's discretion. May also be treated with corticosteroids, NSAIDs, and/or opioid analgesics. If Grade 3–4 tumor flare reaction occurs, hold lenalidomide until reaction resolves to Grade ≤1.

Lab Test Considerations:

• Verify negative pregnancy status before starting therapy. In women of reproductive potential, obtain two negative pregnancy tests before starting lenalidomide. Pregnancy tests with a sensitivity of ≥50 mIU/mL must be done 10–14 days and 24 hr before starting therapy; then verify negative pregnancy test weekly during 1st 4 wk of use, every 4 wk if menstrual cycle is regular, and every 2 wk if cycle is irregular.

  • Patients taking lenalidomide for multiple myeloma with dexamethasone or as maintenance therapy: Monitor CBC every 7 days for 1st 2 cycles, on days 1 and 15 of Cycle 3, and every 28 days thereafter. Patients taking lenalidomide for myelodysplastic syndrome: Monitor CBC with differential weekly for 1st 8 wk of therapy and at least monthly thereafter. Patients taking lenalidomide for mantle cell lymphoma: Monitor CBC weekly for 1st 28 days, every 2 wk during Cycles 2–4, and monthly thereafter. May require dose interruption and/or ↓ and support with blood or growth factors.

  • May cause neutropenia with an average onset of 42 days and recovery time of 17 days. Multiple myeloma: For ANC <1000/mcL, hold and follow CBC weekly until ANC ≥1000/mcL and neutropenia is the only toxicity; resume at initial dose. If concurrent toxicity present, resume at next lower dose. For each subsequent occurrence of ANC <1000/mcL, hold until ANC ≥1000/mcL; then resume at next lower dose. Do not administer doses below 2.5 mg once daily. Myelodysplastic syndromes: For neutropenia that develops ≤4 wk of starting at a dose of 10 mg once daily with baseline ANC ≥1000/mcL and ↓ to <750/mcL, hold until ANC ≥1000/mcL; then resume at 5 mg once daily. If baseline ANC <1000/mcL and ↓ to <500/mcL, hold until ANC ≥500/mcL; then resume at 5 mg once daily. For neutropenia that develops after 4 wk of therapy at a dose of 10 mg once daily and ANC <500/mcL for ≥7 days or <500/mcL with fever ≥38.5°C, hold until ANC ≥500/mcL; then resume at 5 mg once daily. For neutropenia that develops at dose of 5 mg once daily and ANC <500/mcL for ≥7 days or <500/mcL with fever ≥38.5°C, hold until ANC ≥500/mcL; then resume at 2.5 mg once daily. Mantle cell lymphoma: For ANC <1000/mcL for ≥7 days or <1000/mcL with fever ≥38.5°C or <500/mcL, hold and follow CBC weekly until ANC ≥1000/mcL; then ↓ dose by 5 mg/day. Do not administer doses <5 mg once daily. Marginal zone lymphoma or follicular lymphoma: For ANC <1000/mcL for ≥7 days or <1000/mcL with fever ≥38.5° C or <500/mcL, hold and follow CBC weekly until ANC ≥1000/mcL. If starting dose was 20 mg daily, ↓ dose by 5 mg/day. Do not administer doses <5 mg/day If starting dose was 10 mg daily, ↓ dose by 5 mg/day. Do not administer doses <2.5 mg/day.

  • May cause thrombocytopenia with an onset of 28 days (range 8–290 days) and a recovery in 22 days (range 5–224 days). Multiple myeloma: If platelets <30,000/mcL, hold and follow CBC weekly. When platelets ≥30,000/mcL, restart lenalidomide at next lower dose. For each subsequent drop in platelets to <30,000/mcL, interrupt therapy. When platelets ≥30,000/mcL, resume at next lower dose. Do not administer doses below 2.5 mg once daily. Myelodysplastic syndrome: If thrombocytopenia develops within 4 wk of starting a dose of 10 mg once daily with a platelet baseline of ≥100,000/mcL and ↓to <50,000/mcL, hold and resume at 5 mg once daily when platelets >50,000/mcL. If platelet baseline <100,000/mcL and ↓ to 50% of baseline, hold therapy. If platelet baseline ≥60,000/mcL and returns to ≥50,000/mcL or if platelet baseline <60,000/mcL and returns to ≥30,000/mcL, resume at 5 mg once daily. If thrombocytopenia develops after 4 wk of treatment at 10 mg once daily and platelets <30,000/mcL or <50,000/mcL with platelet transfusions, hold therapy. When platelets return to ≥30,000/mcL without hemostatic failure, resume therapy at 2.5 mg once daily. Mantle cell lymphoma: If platelets fall to <50,000/mcL, hold and follow CBC weekly. If platelets return to ≥50,000/mcL, ↓ dose by 5 mg/day. Do not administer doses <5 mg/day. Follicular lymphoma or marginal cell lymphoma: If platelets <50,000/mcL, hold and follow CBC weekly. When platelets return to ≥50,000/mcL, if starting dose was 20 mg daily, ↓ dose by 5 mg/day; do not administer doses <5 mg/day. If starting dose was 10 mg daily, ↓ dose by 5 mg/day; do not administer doses <2.5 mg/day.

  • Monitor liver enzymes periodically during therapy. Stop therapy if enzymes are ↑; may resume when return to normal or ↓ dose.
  • May cause anemia and leukopenia.
  • May cause hypokalemia and hypomagnesemia.
  • Monitor thyroid function before starting and periodically during therapy.