Although has affinity for AMY1 (CTR/RAMP1) receptor with a Ki value of 0.75 nM, MK 3207 displays marked selectivity for human CGRP receptor versus related human AM1 (CLR/RAMP2) receptor, AM2 (CLR/RAMP3) receptor, AMY3 (CTR/RAMP3) receptor, and CTR with Ki values of 16.5 uM, 0.156 uM, 0.128 uM and 1.9 uM, respectively.