Phase III Study of Afatinib or Cisplatin Plus Pemetrexed in Patients With Metastatic Lung Adenocarcinoma With EGFR Mutations

SUMMARY: GILOTRIF® (Afatinib) is an oral, irreversible blocker of the ErbB family which includes EGFR (ErbB1), HER2 (ErbB2), ErbB3 and ErbB4. The approval of GILOTRIF® was based on a multi-center, international, open-label, randomized, phase III trial, in which 345 patients with Stage IIIB (wet)/IV lung adenocarcinoma, with tumors demonstrating Epidermal Growth Factor Receptor (EGFR) exon 19 deletions or exon 21 (L858R) substitution mutations, as detected by an FDA-approved test, were enrolled in a 2:1 ratio. Patients were randomized to receive GILOTRIF® 40 mg orally once daily (n=230) or ALIMTA® (Pemetrexed)/Cisplatin (n=115) given every 21 days for up to six cycles. Patients were stratified according to EGFR mutation status (exon 19 deletion vs. exon 21 L858R vs. ‘other’) and race (Asian vs. non-Asian). The primary endpoint was Progression Free Survival (PFS). The median PFS in the GILOTRIF® group was 11.1 months and 6.9 months in the chemotherapy group (HR= 0.58, P<0.001). In patients whose tumors demonstrated EGFR mutations, the median PFS was 13.6 months in the GILOTRIF® arm and 6.9 months in the chemotherapy arm (HR= 0.47, P<0.001). Objective response rates were 56% and 23% in the GILOTRIF® and chemotherapy groups respectively (P=0.001). There was no statistically significant difference in overall survival between the two treatment groups. The most frequent adverse reactions in the GILOTRIF® group were skin rash, pruritus, stomatitis, diarrhea and decreased appetite. The authors concluded that GILOTRIF® is better than chemotherapy in the first line treatment of EGFR mutant Non Small Cell Lung Cancer patients. However, it remains to be seen if this agent is superior to TARCEVA® (Erlotinib) and IRESSA® (Gefitinib). Sequist LV, Yang JC, Yamamoto N, et al. J Clin Oncol 2013;31:3327-3334