A randomized phase III study optimizing adjuvant osimertinib for resected EGFR -mutant stage II–III non-squamous non-small cell lung cancer: OASIS trial (JACTOP-01)
The OASIS trial [Japan Cancer Treatment Optimization group (JACTOP)-01] is a multicenter, randomized, open-label, phase III study optimizing adjuvant osimertinib therapy for patients with completely resected, epidermal growth factor receptor (EGFR)-mutated (exon 19 deletion or L858R) stage II-III non-squamous non-small cell lung cancer. Based on the ADAURA trial, the standard adjuvant dose of osimertinib is 80 mg/day, which often causes significant adverse events and financial toxicity. This trial evaluates the non-inferiority of a reduced dose of 40 mg/day of osimertinib compared to the standard 80 mg/day. A total of 420 patients will be randomized (1:1) to receive either osimertinib 80 or 40 mg/day orally for 3 years. The primary endpoint is disease-free survival. Secondary endpoints include overall survival, central nervous system disease-free survival, safety, and quality of life. If non-inferiority is confirmed, osimertinib 40 mg/day will establish a new optimal adjuvant strategy, improving patient quality of life and reducing medical economic burdens.
Authors
- Toyofumi Fengshi Chen-Yoshikawa (ORCID: https://orcid.org/0000-0003-0494-7077)
- Shinichi Toyooka (ORCID: https://orcid.org/0000-0002-7588-6745)
- Shun-ichi I. WATANABE (ORCID: https://orcid.org/0000-0003-4456-3932)
- Masataka Taguri (ORCID: https://orcid.org/0000-0001-8902-0056)
- Yasushi Goto (ORCID: https://orcid.org/0000-0002-7437-5054)
- Satoshi Shiono (ORCID: https://orcid.org/0000-0003-4087-635X)
- Yujin Kudo (ORCID: https://orcid.org/0000-0003-3187-9970)
- Masaya Yotsukura (ORCID: https://orcid.org/0000-0001-7012-7961)
- Yoshimasa Maniwa (ORCID: https://orcid.org/0000-0001-5315-9718)
- Tomonori Mizutani (ORCID: https://orcid.org/0000-0002-9345-1526)
- Keisuke Asakura (ORCID: https://orcid.org/0000-0002-4491-3456)
- Ken Onodera (ORCID: https://orcid.org/0000-0002-2571-8815)
- Hideo Kunitoh (ORCID: https://orcid.org/0000-0002-6183-7774)
- Norihiko Ikeda (ORCID: https://orcid.org/0000-0002-5141-8808)
- Nodoka Seya
- Yoshinori Okada
- the Japan Cancer Treatment Optimization group (JACTOP)
Institutions
- Yamagata University (JP)
- Tokyo Medical University (JP)
- Okayama University (JP)
- Keio University (JP)
- National Cancer Center (US)
- Tohoku University Hospital (JP)
- Japanese Red Cross Medical Center (JP)
- Keio University Hospital (JP)
- Tokyo Metropolitan Hiroo Hospital (JP)
- Yamagata Research Institute Of Technology (JP)
- National Cancer Center Hospital (JP)
- National Cancer Research Institute (GB)
- Nagoya University (JP)
- Kobe University (JP)
Publication Details
- Journal
- Japanese Journal of Clinical Oncology
- Published
- 2026-10-29
- DOI
- https://doi.org/10.1093/jjco/hyag185
- Primary Topic
- Lung Cancer Treatments and Mutations
- Type
- article
- Field-Weighted Citation Impact
- 0.00