lenalidomide + quinidine

Lenalidomide + quinidine is a **combination of two small molecule drugs**, each with distinct pharmacological actions. **Lenalidomide** is an immunomodulatory, antineoplastic, and anti-angiogenic agent approved mainly for hematologic malignancies such as multiple myeloma and myelodysplastic syndromes. Its mechanism involves binding to cereblon, altering the activity of the E3 ubiquitin ligase complex, leading to the degradation of specific transcription factors, modulating cytokine production, and enhancing tumor cell apoptosis and immune response. **Quinidine** is a class Ia antiarrhythmic and antimalarial small molecule, used primarily for the management and prophylaxis of atrial fibrillation/flutter and ventricular arrhythmias. It blocks voltage-gated sodium channels, prolongs the cardiac action potential, acts as an α-adrenergic antagonist, and inhibits P-glycoprotein (P-gp), altering the pharmacokinetics of some co-administered drugs. In healthy volunteer studies, their co-administration did not produce clinically significant pharmacokinetic interactions, as quinidine did not affect the renal excretion or plasma concentration of lenalidomide, and no major safety concerns were observed.