MATERIALS AND METHODS: Two EGFR mutation tests, a tissue-based assay (cobas® v1) and a tissue- and blood-based assay (cobas® v2) were used to analyze matched biopsy and blood samples (897 paired samples) from three Asian studies of first-line erlotinib with similar intent-to-treat populations. ENSURE was a phase III comparison of erlotinib and gemcitabine/platinum, FASTACT-2 was a phase III study of gemcitabine/platinum plus erlotinib or placebo, and ASPIRATION was a single-arm phase II study of erlotinib. Agreement statistics were evaluated, based on sensitivity and specificity between the two assays in subgroups of patients with increasing tumor burden.
RESULTS: Patients with discordant EGFR (tissue+/plasma-) mutation status achieved longer progression-free and overall survival than those with concordant (tissue+/plasma+) mutation status. Tumor burden was significantly greater in patients with concordant versus discordant mutations. Pooled analyses of data from the three studies showed a sensitivity of 72.1% (95% confidence interval [CI] 67.8-76.1) and a specificity of 97.9% (95% CI 96.0-99.0) for blood-based testing; sensitivity was greatest in patients with larger baseline tumors.
CONCLUSIONS: Blood-based EGFR mutation testing demonstrated high specificity and good sensitivity, and offers a convenient and easily accessible diagnostic method to complement tissue-based tests. Patients with a discordant mutation status in plasma and tissue, had improved survival outcomes compared with those with a concordant mutation status, which may be due to their lower tumor burden. These data help to inform the clinical utility of this blood-based assay for the detection of EGFR mutations.
METHODS: In this open-label phase III study (PROFILE 1029), patients were randomized 1:1 to receive orally administered crizotinib 250 mg twice daily continuously (3-week cycles) or intravenously administered chemotherapy (pemetrexed 500 mg/m2, plus cisplatin 75 mg/m2, or carboplatin [at a dose to produce area under the concentration-time curve of 5-6 mg·min/mL]) every 3 weeks for a maximum of six cycles. PFS confirmed by independent radiology review was the primary end point.
RESULTS: Crizotinib significantly prolonged PFS (hazard ratio, 0.402; 95% confidence interval [CI]: 0.286-0.565; p < 0.001). The median PFS was 11.1 months with crizotinib and 6.8 months with chemotherapy. The objective response rate was 87.5% (95% CI: 79.6-93.2%) with crizotinib versus 45.6% (95% CI: 35.8-55.7%) with chemotherapy (p < 0.001). The most common adverse events were increased transaminase levels, diarrhea, and vision disorders with crizotinib and leukopenia, neutropenia, and anemia with chemotherapy. Significantly greater improvements from baseline in patient-reported outcomes were seen in crizotinib-treated versus chemotherapy-treated patients.
CONCLUSIONS: First-line crizotinib significantly improved PFS, objective response rate, and patient-reported outcomes compared with standard platinum-based chemotherapy in East Asian patients with ALK-positive advanced NSCLC, which is similar to the results from PROFILE 1014. The safety profiles of crizotinib and chemotherapy were consistent with those previously published.
METHODS: Eligible Asian patients (enrolled at Asian sites) who were at least 18 years of age (≥20 years in Japan) and had untreated EGFR-mutated advanced NSCLC were randomized 1:1 to receive osimertinib (80 mg, orally once daily) or an SoC EGFR TKI (gefitinib, 250 mg, or erlotinib, 150 mg, orally once daily). The primary end point was investigator-assessed progression-free survival (PFS). The key secondary end points were overall survival, objective response rate, central nervous system efficacy, and safety.
RESULTS: The median PFS was 16.5 versus 11.0 months for the osimertinib and SoC EGFR TKI groups, respectively (hazard ratio = 0.54, 95% confidence interval: 0.41-0.72, p < 0.0001). The overall survival data were immature (24% maturity). The objective response rates were 80% for osimertinib and 75% for an SoC EGFR TKI. The median central nervous system PFS was not calculable for the osimertinib group and was 13.8 months for the SoC EGFR TKI group (hazard ratio = 0.55, 95% confidence interval: 0.25-1.17, p = 0.118). Fewer adverse events of grade 3 or higher (40% versus 48%) and fewer adverse events leading to treatment discontinuation (15% versus 21%) were reported with osimertinib versus with an SoC EGFR TKI, respectively.
CONCLUSION: In this Asian population, first-line osimertinib demonstrated a clinically meaningful improvement in PFS over an SoC EGFR TKI, with a safety profile consistent with that for the overall FLAURA study population.
RESULTS: All of the mutations were found in adenocarcinoma, except one that was in squamous cell carcinoma. The mutation rate was 45.7% (221/484). Complex mutations were also observed, wherein 8 tumours carried 2 mutations and 1 tumour carried 3 mutations.
CONCLUSIONS: Both methods detected EGFR mutations in FFPE samples. HRM assays gave more EGFR positive results compared to Scorpion ARMS.