Phase 1/2 study of alectinib in RET-rearranged previously-treated non-small cell lung cancer (ALL-RET)

Shinji Takeuchi, Noriko Yanagitani, Takashi Seto, Yoshihiro Hattori, Kadoaki Ohashi, Masahiro Morise, Shingo Matsumoto, Kiyotaka Yoh, Koichi Goto, Makoto Nishio, Shizuko Takahara, Takahiro Kawakami, Yasuhito Imai, Kenichi Yoshimura, Azusa Tanimoto, Akihiro Nishiyama, Toshinori Murayama, Seiji Yano

Research output: Contribution to journalArticlepeer-review

12 Citations (Scopus)


Background: Rearranged during transfection (RET) rearrangements occur in 1-2% of non-small cell lung cancers (NSCLCs). Alectinib administered at doses of 300 mg and 600 mg twice daily (BID) is approved for ALK-rearranged NSCLC in Japan and other countries, respectively. Since alectinib has activity against RET, we conducted a phase (P) 1/2 study of alectinib to determine its activity in Japanese patients with RET-rearranged NSCLC. Methods: This study was a single-arm, open-label, multi-institutional P1/2 trial. Previously treated patients with RET-rearranged NSCLC, screened by nation-wide network (LC-SCRUM-Japan), were recruited. In P1, alectinib (600 or 450 mg BID) was administered following a 3+3 design and its safety was assessed. During P2, alectinib was administered at the recommended dose (RD) determined in P1. The primary endpoint was the objective response rate (ORR) in RET inhibitor-naïve patients treated with the RD of alectinib. Results: Thirty-four patients were administered alectinib. In cohort 1 (600 mg BID) of P1, we observed 5 dose-limiting toxicities (DLTs), including grade 3 rash and thromboembolic event, in 3 of 6 patients. In cohort 2 (450 mg BID), we observed no DLTs in 3 patients. Pharmacokinetic analysis revealed that AUC0-10 to 600 mg BID was higher than that previously reported in global trials. We determined 450 mg BID as the RD for P2. In 25 RET inhibitor-naïve patients, one achieved an objective response (4%) and 13 achieved disease control at 8 weeks (52%). The median progression-free survival (PFS) was 3.4 months (95% CI, 2.0-5.4), while the median overall survival was 19.0 months (5.4-NE). We observed grade 3 adverse events (AEs) (4%) including pneumonitis in P2. Conclusions: Alectinib exerts limited activity against RET-rearranged NSCLC. Further investigation to elucidate the mechanisms underlying sensitivity and resistance of RET inhibitors is required to improve outcomes for these patients.

Original languageEnglish
Pages (from-to)314-325
Number of pages12
JournalTranslational Lung Cancer Research
Issue number1
Publication statusPublished - Jan 2021


  • Alectinib
  • Clinical trial
  • Lung cancer
  • Precision medicine
  • RET rearrangement
  • Rearranged during transfection (RET)

ASJC Scopus subject areas

  • Oncology


Dive into the research topics of 'Phase 1/2 study of alectinib in RET-rearranged previously-treated non-small cell lung cancer (ALL-RET)'. Together they form a unique fingerprint.

Cite this