A BB3 receptor antagonist; inhibits [125I]BA1 binding to NCI-H1299 lung cancer cells transfected with human BB3 receptors (IC50 = 4.8 μM); selective for BB3 over GRPR and NMBR (IC50s = 16 and >100 μM, respectively, in a radioligand binding assay); reversibly inhibits BA1-induced increases in cytosolic calcium in NCI-H1299 cells at 16 μM; inhibits BA1-induced phosphorylation of ERK and EGFR and reduces proliferation of NCI-H1299 cells