On Jun. 14, 1996, topotecan (Hycamptin), the first of a class of drugs that interferes with the enzyme topoisomerase I, was approved for use by the U.S. Food and Drug Administration (FDA) for previously treated patients with advanced ovarian cancer.

For these patients, topotecan provides another therapeutic option upon disease progression after initial platinum-based chemotherapy. Topotecan also has activity in other tumor types, including small-cell lung cancer, hematologic malignancies and pediatric neuroblastoma and rhabdomyosarcoma. Topotecan combination regimens with paclitaxel (Taxol), etoposide (VePesid), cisplatin (Platinol), and cytarabine and with other treatment modalities, such as radiation therapy, are in development.

Studies evaluating topotecan combinations as initial treatment in such diseases as ovarian and small-cell lung carcinoma were also underway. Topotecan is derived from the bark of a Chinese tree known as Camptotheca acuminata.