Efficacy of pemetrexed as second-line therapy in advanced NSCLC after either treatment-free interval or maintenance therapy with gemcitabine or erlotinib in IFCT-GFPC 05-02 phase III study.

7574 Background: Continuous exposure of tumor cells to maintenance therapy in advanced NSCLC might lead to resistance to subsequent treatments. IFCT–GFPC 0502 study showed a progression-free survival (PFS) benefit with gemcitabine (G) or erlotinib (E) maintenance compared to observation (O) after cisplatin-G induction chemotherapy. The trial included a pre-defined second-line therapy with pemetrexed (P), allowing post-hoc assessment of its efficacy according to previous maintenance treatment or treatment-free interval. Methods: Stage IIIB/IV NSCLC patients (pts) with a PS of 0-1 were randomized after 4 cycles of cisplatin-G chemotherapy to O or to receive maintenance therapy with G or E until disease progression. P was given as second-line treatment on disease progression in all arms. PFS and OS were assessed from the beginning of P therapy according to randomization arm. Tumor response to P and tolerance were also analyzed. Results: Of the 464 pts randomized to either O (155), G (154) or E (155), 360 pts...