An outlook on the trigeminovascular mechanisms of action and side effects concerns of some potential neuropeptidergic antimigraine therapies.

Introduction: In addition to serotonin (5-hydroxytryptamine; 5-HT) and other (neuro)mediators, the role of neuropeptides in migraine pathophysiology is relevant. Indeed, while some molecules interfering with calcitonin gene-related peptide (CGRP) transmission have recently been approved for clinical antimigraine use, other neuropeptides with translational use are in the pipeline. Among others, hypothalamic neuropeptides such as pituitary adenylate cyclase-activating peptide (PACAP), oxytocin (OT), and orexins stand out as potential novel targets to treat this neurovascular disorder. Areas covered: Based on the aforementioned findings, the present review: (i) summarizes the current knowledge on the role of the above neuropeptides in the trigeminovascular system, and migraine pathophysiology; and (ii) discusses some issues related with the mechanisms of action and side effects concerns that could be elicited when targeting the CGRPergic, PACAPergic, oxytocinergic and orexinergic systems. Expert opinion: Specific antimigraine pharmacotherapies have evolved from the enhancement of serotonergic 5-HT1B/1D/1F transmission to the use of compounds interacting with neuropeptidergic systems. Canonically, neuropeptides cause an array of complex intracellular mechanisms that, after modifying neuronal and/or vascular transmission, result in antimigraine action and also potential side effects. Furthermore, due to the chemical nature of some molecules targeting the above neuropeptidergic transmission (e.g., monoclonal antibodies, peptides), there are some limiting pharmacokinetics issues.