Phase II trial of erlotinib in chemotherapy-naive women with advanced pulmonary adenocarcinoma

摘要: 8065 Background: This single-arm phase II study explored the role of clinical characteristics (female gender, adenocarcinoma histology, no tobacco within 1 year) in selecting pts for 1st-line therapy w/ erlotinib. Available tissue for EGFR mutation analysis was required to assess its impact on outcomes. Methods: Eligible pts were chemotherapy-naïve women, stage IIIB/ IV, PS 0–2, adenocarcinoma, and w/ available tissue for analysis of EGFR mutation status. Pts received erlotinib 150 mg PO daily until disease progression or unacceptable toxicity. Primary endpoint was response rate (RR). Secondary endpoints included toxicity, time to progression (TTP), overall survival (OS), and impact of EGFR genotype on clinical outcomes. Results: From 11/04 - 12/08, 84 pts were treated. Median age 68 (range 34–88); 59 PS 0, 24 PS 1, 1 PS 2; race: 79 white, 3 Asian, 2 black; 16 pts had BAC or predominant BAC features; smoking status: 35 never, 49 former. Tox: Rash (90%; 21% grade 3) and diarrhea (69%; 7% grade 3) were the most common toxicities. 32 pts developed toxicity grade 3+ felt likely related to erlotinib. 2 deaths may be treatment-related (1 DIC, 1 hepatic failure). There were also 3 pts w/ PE's (1 fatal). Efficacy: Response (n=84): 0 CR, 27 PR (RR 32%), 27 SD, 23 PD. 7 pts not evaluable (5 tox, 1 non-progression death, 1 withdrawn consent). Median TTP was 5.6 months (95% CI 4.1–7.4 mos), and median OS was 22.7 months (95% CI 15.8 - 26.0 mos). At the time of analysis, there were 36 deaths, 16 pts on treatment w/o progression, and 5 pts lost to follow-up. Compared to smokers, never-smokers trended toward improved RR (43% vs 22%, p=.06), w/ improved TTP (HR .59; 95%CI .36-.96) but no improvement in OS (HR 1.15, 95%CI .58–2.27). Genotype had a more obvious impact on outcomes: compared w/ 37 known wild-type EGFR, 33 pts w/ known sensitizing mutations had a higher response rate (70% vs 0), and significantly improved hazard ratios for both TTP (.20, 95%CI .11-.36) and OS (.36, 95% CI .18 - .73). Results will be updated and outcomes for rarer mutations will be reported. Conclusions: Clinical characteristics may help select appropriate pts for first-line erlotinib when EGFR mutation status is unavailable. However, when available, EGFR genotype is superior to clinical phenotype in selecting pts for first-line erlotinib. [Table: see text]