Pemetrexed as a single agent in the therapy of advanced lung cancer.

Pemetrexed is a multitargeted antifolate with activity as a single agent against non-small cell lung cancer at a recommended dose of 500 mg/m(2) as a 10-minute infusion every 21 days. The response rate in untreated patients with stage IIIB/IV disease is from 18% to 23%. It is also active in the second-line setting in patients progressing after pretreatment with a number of drugs or after a very short treatment-free interval. The response rate in these difficult-to-treat patients is approximately 9%. Toxicity in both situations is mild; myelotoxicity is primarily seen. This review describes phase I and II studies performed before folic acid and vitamin B(12) supplementation.