Temozolomide was granted accelerated approval by the FDA after a recommendation from the Oncologic Drugs Advisory Committee. Drugs are given accelerated approval because they are products that treat serious conditions that have no other acceptable alternative treatment or because they provide a meaningful therapeutic benefit over existing treatments. Temozolomide was granted orphan status in 1998, which means the FDA provided incentives to its manufacturer to develop it for use in small populations of patients.

Researchers studied 162 patients with anaplastic astrocytoma, who had previously received radiation therapy and who may have had nitrosourea with or without other chemotherapy. Fifty-four patients had disease progression despite therapy with both nitrosourea and procarbazine, the standard chemotherapy regimen. Those patients were given 150 milligrams per meter squared of temozolomide ? in other words, the dosage was based on a formula that combined the height and weight of the patient in order to calculate the body surface area.

A partial response was found in 13 percent of the patients, and a complete response was found in nine percent of the patients. A complete response (CR) is defined as no detectable tumor for two consecutive months and a partial response (PR) is considered as a decrease of more than 50 percent in the tumor area for more than two consecutive months. Overall survival at six months was 74 percent and overall survival at 12 months was 65 percent.

The most common side effects were nausea, vomiting, headache, fatigue, and constipation. Temozolomide will be marketed and sold by the Schering-Plough Corporation under the name Temodar.