Drug Class: Immunomodulatory drug (IMiD)
Mechanism of Action:
- Lenalidomide has multiple mechanisms:
- Modulates immune function: Enhances T-cell and NK-cell activity, inhibits pro-inflammatory cytokines (e.g., TNF-α).
- Direct antineoplastic effect: Induces apoptosis of malignant cells.
- Alters bone marrow microenvironment.
- Inhibits angiogenesis.
- In MDS, particularly in del(5q) subtype, it suppresses the malignant clone and improves erythropoiesis
FDA-Approved Indications
- Myelodysplastic Syndromes (MDS):
- Specifically for transfusion-dependent anemia due to IPSS low- or intermediate-1-risk MDS with deletion 5q (with or without additional cytogenetic abnormalities).
Also approved for:
- Multiple myeloma (with dexamethasone)
- Mantle cell lymphoma
- Follicular and marginal zone lymphoma
Dosing in MDS
- Starting dose: 10 mg orally once daily for 21 days of a 28-day cycle
- Dose adjustments required for:
- Renal impairment (primary route of excretion)
- Hematologic toxicity
Adverse Effects
- Hematologic: Neutropenia, thrombocytopenia, anemia
- Thromboembolic: DVT, PE (especially in MM with dexamethasone)
- GI: Diarrhea, constipation
- Dermatologic: Rash, pruritus
- Secondary malignancies: Rare but notable in long-term use
Monitoring Parameters
- CBC with differential: Baseline and frequently during treatment (e.g., weekly initially)
- Renal function: Dose adjust for CrCl <60 mL/min
- Signs of thrombosis: Consider prophylaxis if other risk factors present
- Pregnancy: Strict adherence to REMS program due to teratogenicity
Clinical Pearls
- Highly effective in MDS with isolated del(5q) → high rates of transfusion independence and cytogenetic remission.
- Not effective in patients without del(5q) unless part of clinical trial.
- Must enroll in REMS program (due to thalidomide-like teratogenicity).
- Use caution with concomitant myelosuppressive agents.