FLAURA2

一行要約

未治療 EGFR 変異陽性 (ex19del / L858R) NSCLC 1L における Osimertinib + Platinum/Pemetrexed vs Osimertinib monotherapy の phase III。PFS HR 0.62 (25.5 vs 16.7 mo) で有意な PFS 延長を示し、3rd-gen EGFR-TKI に化学療法を上乗せする併用戦略の有効性を前向きに証明。OS データは未成熟。

試験デザイン

• 対象: Stage IIIB-IV NSCLC、EGFR ex19del or L858R、未治療、ECOG PS 0-1、安定脳転移許容、N=557 (1:1)
• 介入群 (n=279) : Osimertinib 80 mg/day + Cisplatin or Carboplatin + Pemetrexed Q3W × 4 cycles → Osimertinib + Pemetrexed maintenance
• 対照群 (n=278) : Osimertinib 80 mg/day monotherapy
• 層別化: 変異タイプ (ex19del vs L858R)、人種 (Asian vs non-Asian)、CNS metastases (あり vs なし)
• 主要評価項目: PFS (investigator 判定)

主要結果

• PFS (primary) : HR 0.62 (95% CI 0.49–0.79, p<0.001)、median 25.5 vs 16.7 mo
• 18-month PFS rate: 65% vs 48%
• ORR: 80% vs 76% (差軽微)
• CNS PFS: 脳転移あり群で HR 0.47 (CNS control の改善が顕著)
• OS: Interim — HR 0.78 (95% CI 0.58–1.06)、未成熟。最終 OS 解析が待たれる
• Grade ≥3 AE: 併用群 64% vs monotherapy 27%。好中球減少 (15%)、貧血 (13%) が増加。QOL への影響は manageable と報告
• Mutation 別: ex19del (HR 0.60)、L858R (HR 0.63) で一貫した benefit

臨床的意義

• TKI+化療併用の新パラダイム: FLAURA (Osimertinib monotherapy) が確立した 1L 標準に対し、化学療法の上乗せ benefit を証明。「best TKI に化療を加えるべきか」という 10 年来の問いに対する回答
• PFS-OS gap の議論: PFS は有意に延長するが OS 未成熟。Toxicity 増加 (Grade ≥3 AE 64% vs 27%) との trade-off で OS benefit が confirmation されるまでは universal adoption に慎重な意見あり
• CNS benefit: 脳転移あり群での PFS HR 0.47 は臨床的に重要。CNS sanctuary site への化療の added value を示唆
• MARIPOSA との比較: Lazertinib + Amivantamab (MARIPOSA) も 1L で PFS HR 0.70 を示しており、1L EGFR+ における「chemo add-on vs bispecific add-on」の indirect comparison が次の論点

Open Questions

• OS final analysis: PFS benefit が OS に translate されるか。Crossover / post-progression therapy の影響
• FLAURA2 vs MARIPOSA indirect comparison: TKI+chemo vs TKI+bispecific Ab の efficacy / toxicity balance
• Patient selection: 全例に化療を上乗せすべきか、脳転移あり / L858R / high tumor burden 例に限定すべきか
• Biomarker for chemo benefit: TP53 co-mutation、ctDNA dynamics 等による chemo add-on benefit 予測

重要論文 Top 10

1. ★★★★★ Janne et al. NEnglJMed 2026 — Primary publication — PFS HR 0.62、TKI+chemo 1L
2. Soria et al. (FLAURA) — Osimertinib monotherapy 1L — 比較基盤
3. ★★★★ Hosomi et al. JClinOncol 2020 (NEJ009) — Gefitinib + chemo vs Gefitinib — 1st-gen での TKI+chemo 先行検証
4. Cho et al. NEnglJMed 2024 (MARIPOSA) — Amivantamab+Lazertinib 1L — 競合レジメン
5. ★★★★★ Ramalingam et al. NEnglJMed 2020 (FLAURA OS) — FLAURA OS — monotherapy の long-term outcome

関連エンティティ・概念

• 薬剤: Osimertinib / Platinum-chemotherapy / Pemetrexed
• 関連試験: FLAURA (Osimertinib mono 1L) / LAURA (Stage III consolidation) / ADAURA (adjuvant) / NEJ002
• 関連遺伝子: EGFR (ex19del, L858R) / TP53
• ドメイン: lung-cancer-treatment

関連論文

Basic-Brain metastasis

• Mavrikios et al. AnnOncol 2026 — Lung cancer brain metastases management at the dawn of personalized medicine are we ready to break the barriers

Basic-Oncogene and genetics

• Bhang et al. NatMed 2015 — Studying clonal dynamics in response to cancer therapy using high-complexity barcoding

Clinical-NSCLC-Driver-Other

• Kropf-Sanchen et al. ClinLungCancer 2026 — A retrospective, multicenter analysis within the national network genomic medicine lung cancer in germany to detect RET

Clinical-NSCLC-EGFR

• Kobayashi et al. CancerSci 2016 — Not all epidermal growth factor receptor mutations in lung cancer are created equal perspectives for individualized
• Nishio et al. CancerSci 2020 — Ramucirumab or placebo plus erlotinib in EGFR-mutated, metastatic non-small-cell lung cancer east asian subset of RELAY
• HARMONi et al. JAMA 2026 — A-Bispecific antibody ivonescimab added to chemotherapy in EGFR-variant non-small cell lung cancer the HARMONi-A
• Li et al. LancetOncol 2026 — Aumolertinib with or without chemotherapy in EGFR-mutated advanced non-small-cell lung cancer (AENEAS2) an open-label,
• Soria et al. NEnglJMed 2018 — Osimertinib in untreated EGFR-mutated advanced non-small-cell lung cancer
• Ramalingam et al. NEnglJMed 2020 — Overall survival with osimertinib in untreated, EGFR-mutated advanced NSCLC
• Cho et al. NEnglJMed 2024 — Amivantamab plus lazertinib in previously untreated EGFR-Mutated advanced NSCLC
• Janne et al. NEnglJMed 2026 — Survival with osimertinib plus chemotherapy in EGFR-mutated advanced nsclc
• Blakely et al. NatGenet 2017 — Evolution and clinical impact of co-occurring genetic alterations in advanced-stage EGFR-mutant lung cancers
• Zhao et al. NatRevClinOncol 2026 — Navigating the landscape of EGFR TKI resistance in EGFR-mutant NSCLC-mechanisms and evolving treatment approaches