Study showed Alimta improved survival in certain types of Non-Small Cell Lung Cancer

The type of non-small cell lung cancer (NSCLC) patients have may now influence their treatment regimen and, in turn, survival outcome according to the results of a major study published online in the Journal of Clinical Oncology.

NSCLC is the most common type of lung cancer and represents 85 to 90 percent of all lung cancers. According to the World Health Organization (WHO) Cancer Report, lung cancer is the world's most common cancer and the leading cause of cancer death for both men and women. More than 1 million people die from lung cancer each year.

NSCLC is defined as a group of histologies i.e. tumour types differentiated by cellular structure. The most common NSCLC histology types are squamous (or epidermoid) carcinoma, adenocarcinoma, and large cell carcinoma. These histologies are often classified together because, to date, approaches to diagnosis, staging, prognosis, and treatment have been similar.

The study, the largest Phase III clinical trial in the first-line NSCLC setting, evaluated ALIMTA® (pemetrexed for injection) plus cisplatin versus GEMZAR® (gemcitabine HCl for injection) plus cisplatin, a standard of treatment in this setting. The trial met its primary endpoint of non-inferiority relative to overall survival.

Additionally, in a pre-planned histological analysis, patients with either adenocarcinoma or large-cell carcinoma had a statistically superior and clinically relevant improvement in overall survival when treated with the pemetrexed regimen in the first-line setting.

In comparison, patients with squamous cell histology were found to have a more favorable overall survival when treated with the gemcitabine regimen.

The overall survival of patients treated with either the pemetrexed regimen or gemcitabine regimen was found to be non-inferior, with a median survival of 10.3 months. However, when researchers reviewed survival rates according to histological analysis, it was found that patients with adenocarcinoma achieved 12.6 months of overall median survival when treated with the pemetrexed regimen compared to 10.9 months for those treated with the gemcitabine regimen. Patients with large cell carcinoma who were treated with the pemetrexed regimen achieved 10.4 months of overall median survival versus 6.7 months for those treated with the gemcitabine regimen. Both findings are statistically significant.

Patients with squamous cell histology were found to have a more favorable rate of survival when treated with the gemcitabine regimen, achieving 10.8 months of median survival, compared to the 9.4 months for those treated with the pemetrexed regimen. This finding was statistically significant.

The Phase III, randomized study compared the overall survival between pemetrexed+cisplatin versus gemcitabine+cisplatin in chemonaive patients (1,725) with stage IIIB or IV NSCLC who also exhibited a performance status of 0-1. Patients on the pemetrexed arm (862) were treated with pemetrexed (500 mg/m2) and cisplatin (75 mg/m2) on day one every three weeks for up to six cycles. Patients on the gemcitabine arm (863) were treated with cisplatin (75 mg/m2) on day one and gemcitabine (1250 mg/m2) on days one and eight every three weeks for up to six cycles.

Hematologic grade 3/4 drug-related toxicities including neutropenia, anemia and thrombocytopenia were significantly lower for patients on the pemetrexed arm. Drug-related grade 3/4 febrile neutropenia and alopecia (all grades) were also significantly less on the pemetrexed arm. Drug-related grade 3/4 nausea was more common in patients treated with pemetrexed. Safety data by histology was generally consistent with the overall safety results.

Overall, patients with adenocarcinoma or large cell carcinoma histologies achieved improvement in overall survival when treated with Alimta (pemetrexed) based regimens.

While non-small cell lung cancer has typically been treated as one disease, this study confirms that histology, or tumour type, can provide a clue as to which treatment regimen works best for a particular tumor type. It suggests that if we can select the therapy for better results, we are closer to improving outcomes for lung cancer.