Lenalidomida Sun (Lenalidomide)

Lenalidomide is an immunomodulatory antineoplastic agent used in hematologic malignancies and related bone‑marrow disorders.

• Multiple myeloma: improves progression‑free survival and overall response rates when used in eligible adult patients, often in combination with dexamethasone.
• Myelodysplastic syndromes: reduces transfusion dependence and modifies disease course in patients with del(5q) cytogenetic abnormality, administered as a single agent or with supportive care.
• Mantle cell lymphoma: contributes to disease control as part of combination regimens in relapsed or refractory cases, enhancing response when paired with other targeted therapies.

• Lenalidomide binds to the cereblon component of the E3 ubiquitin ligase complex, promoting ubiquitination and proteasomal degradation of the transcription factors Ikaros (IKZF1) and Aiolos (IKZF3). This results in modulation of the immune microenvironment, inhibition of angiogenesis, and direct anti‑myeloma activity through apoptosis and cell‑cycle arrest.

Lenalidomide may cause a range of adverse reactions, which are categorized by frequency and severity.

Common Side Effects

• Fatigue: persistent tiredness affecting daily activities.
• Nausea: mild to moderate upset stomach.
• Diarrhea: loose stools occurring intermittently.
• Constipation: reduced bowel movements.
• Rash: skin irritation or redness.
• Low blood counts: mild neutropenia or thrombocytopenia.

Serious or Rare Side Effects

• Deep vein thrombosis or pulmonary embolism: blood clots in veins.
• Severe neutropenia: markedly reduced neutrophil count increasing infection risk.
• Severe thrombocytopenia: dangerously low platelet levels leading to bleeding.
• Secondary primary malignancies: emergence of new cancers.
• Hepatotoxicity: significant liver enzyme elevation.
• Severe allergic reactions: anaphylaxis or Stevens‑Johnson syndrome.

Before initiating therapy, clinicians should consider several safety measures.

• Pregnancy contraindication: Lenalidomide is classified as Category X and must not be used during pregnancy.
• Contraception requirement: both male and female patients of reproductive potential must use effective contraception during treatment and for at least four weeks after the last dose.
• Blood count monitoring: regular complete blood counts are essential to detect neutropenia or thrombocytopenia.
• Thromboembolic risk: assess for additional risk factors and consider prophylactic anticoagulation when appropriate.
• Renal impairment: dose adjustment or avoidance may be needed in patients with severe renal dysfunction.
• Store at ambient temperature: keep below 25 °C, retain in the original packaging, and protect from moisture.

Lenalidomide can interact with other medicines, requiring careful management.

Major Interactions (Avoid)

• Strong CYP3A4 inducers (e.g., rifampin): may markedly reduce lenalidomide exposure and efficacy.
• Concurrent use with other immunomodulatory agents: can increase the risk of severe cytopenias.
• Combination with agents that heighten thrombotic risk (e.g., erythropoiesis‑stimulating agents): may precipitate dangerous clot formation.

Moderate Interactions (Monitor Closely)

• CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin): may increase plasma concentrations and toxicity.
• Non‑steroidal anti‑inflammatory drugs (NSAIDs): can exacerbate renal impairment, especially in patients with pre‑existing kidney disease.
• Live vaccines: immune response may be diminished; avoid administration during therapy.