Etoposid

Etoposid, also known by the code VP-16, is a cytotoxic chemotherapy agent used in the treatment of several cancers. It belongs to the epipodophyllotoxin group and acts as a topoisomerase II inhibitor, producing DNA strand breaks and promoting cancer cell death. Etoposid is derived from the plant podophyllotoxin and is available in intravenous forms (including etoposide phosphate) and as an oral formulation.

Indications and use patterns vary by regimen and cancer type. It is commonly included in combination protocols for testicular cancer and certain germ cell tumors, small cell lung cancer, and various lymphomas. In clinical practice, etoposide is often used as part of regimens such as BEP (bleomycin, etoposide, cisplatin) for testicular cancer or EPOCH-like combinations for lymphomas. The drug is administered under careful dosing schedules and is typically given with close monitoring of blood counts and organ function.

Pharmacokinetics and metabolism vary with route of administration. Oral bioavailability is partial and dose-dependent; IV administration results in rapid systemic exposure. Etoposide is metabolized in the liver and eliminated through renal and biliary routes. The elimination half-life can be affected by renal or hepatic impairment and by concomitant medications.

Adverse effects are mainly dose-limiting and include myelosuppression, nausea and vomiting, mucositis, alopecia, and infusion-related reactions such as transient hypotension. Long-term use carries a risk of secondary malignancies, and the drug should be avoided in pregnancy. Caution is advised with other myelosuppressive agents, hepatic or renal impairment, and in the context of live vaccines. Proper monitoring of blood counts and organ function is essential during therapy.