In phase 2 of ARROW, 233 pts with RET fusion+ NSCLC (KIF5B n=164, CCDC6 n=41, Other n=28) received 400mg/day pralsetinib until progression, intolerance or withdrawal….Median duration of response (DOR) and progression-free survival (PFS) were higher with CCDC6 vs KIF5B RET fusions irrespective of prior treatment.