Pemetrexed in Second-Line Treatment of Non–Small-Cell Lung Cancer
According to the updated 2004 guidelines of the American Societyof Clinical Oncology (ASCO) on the treatment of advanced non–smallcelllung cancer (NSCLC), docetaxel (Taxotere) can be considered thestandard second-line chemotherapy in patients relapsing after frontlinetherapy. This was based on two phase III trials (TAX 317 and TAX320) that demonstrated the superiority of docetaxel at 75 mg/m2 in theparameters of survival, quality of life, and disease/symptom controlwhen compared to best supportive care or alternative single-agent chemotherapy.The response rate was approximately 6%, with a mediansurvival time of 7 months and a 1-year survival rate of 30%. Despitethe activity demonstrated, this schedule showed an important toxicityprofile, with grade 3/4 neutropenia and febrile neutropenia occurringin 70% and 11% of patients, respectively. However, the results obtainedby these studies stimulated research interest in new drugs for this diseasesetting. Pemetrexed (Alimta), a new multitargeted antifolate, hasachieved promising results in NSCLC treatment, as a single agent or incombination with other drugs. In the second-line setting, a large phaseII study demonstrated good activity of pemetrexed, with an acceptabletoxicity profile. This led to a phase III registration trial that comparedpemetrexed at 500 mg/m2 to the standard docetaxel dose of 75 mg/m2.While results from this trial demonstrated a similar efficacy of the tworegimens in response rate and survival, pemetrexed achieved a bettersafety profile. These results support the use of pemetrexed as a newoption in the second-line treatment of NSCLC.
