Same price as Aimovig, and they have a once-every-three-months label as well as a once-a-month. But no self-injector.
FWIW, Aimovig has a listed 3% (for high-dose) constipation AE, but seemingly half of the patient reports online mention this as an issue. There is a plausible mechanism - CGRP is released in the gut in response to toxins and serves to increase motility.