Survival without common toxicity criteria grade 3/4 toxicity following second-line treatment with pemetrexed for nonsquamous non-small cell lung cancer in Chinese patients

Background The efficacy of pemetrexed in the second-line treatment of Chinese patients with advanced non-small cell lung cancer (NSCLC) has been shown to be similar to that of docetaxel in a recent study; additionally, pemetrexed was associated with much better safety and toxicity profiles. Here, the survival without common toxicity criteria grade 3/4 toxicity (SWT) data from a post hoc analysis of this recent prospective NSCLC study in Chinese patients is reported. This post hoc analysis differs from the main study; it focuses on the nonsquamous population to align with the current approval for pemetrexed in China. Methods A total of 154 patients with nonsquamous NSCLC received either pemetrexed (500 mg/m² intravenously (IV)) or docetaxel (75 mg/m² IV) on day 1 of 21-day cycles. SWT was analyzed using Kaplan-Meier and univariate Cox methods. Results Patients treated with pemetrexed had a longer median SWT than patients treated with docetaxel (7.4 months versus 1.2 months; unadjusted hazard ratio =0.59, 95% confidence interval (CI): 0.41-0.84; P=0.003). At 12 and 18 months, the SWT event-free probability for pemetrexed patients (18 months: 24.5%, 95%CI 13.9%-36.6%, vs. 12.3%, 95% CI 4.8%-23.6%) was greater than that for docexatel patients (12 months: 37.3%, 95% CI 26.5%- 48.0%, vs. 23.3%, 95% CI 14.4-33.4). The progressionfree survival without common toxicity criteria grade 3/4 toxicity (PFS-WT) was also statistically significantly longer for patients treated with pemetrexed than patients treated with docetaxel (1.9 months vs. 1.1 months, P=0.002). Conclusions Chinese patients with nonsquamous NSCLC disease treated with pemetrexed had improved SWT beyond 6 months than those receiving docetaxel. This analysis supports a benefit-to-risk profile that favors pemetrexed over docetaxel in the second-line treatment of Chinese nonsquamous NSCLC patients.