The first direct comparison of treating non-squamous lung cancer with either pemetrexed or docetaxel in addition to cisplatin has shown that the two combinations achieve similar progression-free survival, although docetaxel was associated with more frequent adverse events.

At the ESMO 2014 Congress in Madrid, Dr Young-Chul Kim from Chonnam National University Medical School, South Korea, reported the results of an open-label phase III trial that included 149 patients with non-squamous non-small cell lung cancer (NSCLC) conducted at 14 centres in South Korea.

“We wanted to conduct this study because pemetrexed plus platinum chemotherapy is the most commonly used regimen for treating patients with non-squamous NSCLC whose cancer does not have mutations that can be targeted by specific inhibitors,” Kim explained.

“However, docetaxel plus platinum is another effective regimen in the first line treatment of lung cancer and there has been no direct comparison of pemetrexed plus cisplatin versus docetaxel plus cisplatin.”

In the study, researchers randomly assigned patients with chemotherapy-naive cancer to 3-weekly cisplatin 70 mg/m2 in addition to either docetaxel 60 mg/m2  or pemetrexed 500mg/m2  for up to 4 cycles.

They recorded a median progression-free survival of 4.7 months in those who received the pemetrexed combination, and 4.6 months among those who received docetaxel.

However, the rate of serious adverse events was higher in the docetaxel group, they found, with 24 serious adverse events recorded among pemetrexed patients, and 42 in the docetaxel arm.

Kim notes that recruitment into the study was halted early when pemetrexed maintenance treatment was approved in Korea and its use became widespread.

“As we stopped recruitment prematurely, we could not prove non-inferiority between the arms. However, the pemetrexed plus cisplatin arm was less toxic than the docetaxel plus cisplatin arm, while there was no significant difference in progression-free survival and response rate,” Kim said.

The researchers are continuing to follow patients in the trial to study whether there is any difference in overall survival between the arms.

Commenting on the study, Dr Solange Peters from the University Hospital of Lausanne, Switzerland, noted: "The various available platinum-based regimen demonstrate quite similar activity in NSCLC.”

"While a dedicated larger trial published by Scagliotti in 2008 was able to show some superiority of platinum in combination with pemetrexed in non-squamous NSCLC, this trial also confirms its better tolerability, reinforcing most current international NSCLC treatment guidelines,” Peters said.

Source: ESMO