Cluster headache (CH) is a primary headache included in the trigeminal autonomic cephalalgias (TACs) according to the International Calssification of Headache Disorder, Third Edition. CH is characterized by a multifaceted and incompletely understood pathophysiology. Recent experimental evidence has increasingly emphasized the role of specific microRNAs (miRNAs) in the pathophysiology of primary headaches, including migraine. In a recent study, we observed an upregulation in the gene expression of two miRNAs, miR-382-5p and miR-34a-5p, in peripheral blood mononuclear cells (PBMCs) of subjects with chronic migraine (CM). These miRNAs are involved in inflammation modulation and the release of γ-aminobutyric acid (GABA). Notably, this upregulation correlated with the migraine phenotype and its severity. Several neuropeptides have been established to play an active role in CH. Studies by the Danish group have demonstrated that intravenous administration of CGRP, PACAP, or VIP can induce CH attacks in at least 50% of participants in the active phase of the disease. However, no data currently exists regarding the potential involvement of miRNAs in CH. Given this context, the primary aim of this study is to investigate the gene expression of specific miRNAs (miR-382-5p, miR-34a-5p, and miR-155) in PBMCs and plasma levels of neuropeptides (CGRP, PACAP, VIP) in subjects with episodic CH in the active phase (eCH-act), episodic CH in the remission phase (eCH-rem), chronic CH (cCH), and healthy control subjects (HCs).