Fig. 1

Effects of osimertinib and pemetrexed association in PC9T790M xenograft model. a PC9T790M cells were subcutaneously inoculated into BALB/C nude female mice, and after tumors had reached an average size of approximately 150mm³ the animal were treated with vehicle alone (ctrl), osimertinib (3 mg/kg once per day, five times per week) alone (osi), osimertinib intercalated every week with pemetrexed (100 mg/kg once a day, twice per week) (osi → pem), or osimertinib in combination with pemetrexed intercalated with osimertinib alone (osi + pem → osi). Tumor volume was measured twice per week and data are expressed as volume ± SEM (n = 8 tumors per group). *p < 0.05, **p < 0.01, ****p < 0.0001 vs osimertinib; two-way repeated measures analysis of variance followed by Bonferroni’s post-test. b Body weight was measured twice per week and data are expressed as percent change in body weight ± SEM (n = 8 tumors per group). *p < 0.05 vs osimertinib; two-way repeated measures analysis of variance followed by Bonferroni’s post-test. c The indicated treatments were stopped on day 110, and tumor growth was monitored for further 28 days in four animals per group. d Data are expressed as percent change in tumor volume: t corresponds to the tumor volume on day 138 (28 days after drug removal) and t₀ corresponds to the tumor volume on day 110. **p < 0.01; Student’s t test was used for the comparison of means of the two groups