The major limitation of this study is that HA 121-28 was tested in patients almost without prior RET-TKI exposure, since the current standard treatment for NSCLC patients with RET fusion is Selpercatinib and Pralsetinib, the antitumor activity of HA121-28 after Selpercatinib or Pralsetinib treatment remains unknown. Here, RET is linked to non-small cell lung carcinoma.