copanlisib + rifampin

Copanlisib + rifampin refers to the **co-administration of copanlisib, a pan-class I phosphatidylinositol 3-kinase (PI3K) inhibitor, with rifampin, a strong inducer of cytochrome P450 3A4 (CYP3A4) and P-glycoprotein (P-gp)**. Copanlisib is an intravenous small molecule inhibitor developed primarily for the treatment of relapsed follicular lymphoma and other B-cell malignancies. Rifampin is an oral antibiotic used mainly for tuberculosis and other bacterial infections with potent enzyme-inducing properties that can affect pharmacokinetics of many drugs metabolized by CYP3A4. When given together, rifampin substantially reduces systemic exposure of copanlisib by upregulating its metabolic clearance, resulting in lower plasma concentrations and a shorter half-life. This interaction is clinically significant and use of strong CYP3A4 inducers like rifampin with copanlisib is not recommended due to the risk of reduced efficacy of copanlisib[1][4].