GFB-8438 is a novel, potent, and subtype selective TRP channel subfamily C (TRPC) inhibitor that is equipotent against TRPC4 and TRPC5 with IC50 of 0.18 µM and 0.29 µM, and shows excellent selectivity against TRPC6, other TRP family members , NaV 1.5, as well as limited activity against the hERG channel.