Targeting the 5-HT _1B/1D and 5-HT _1F receptors for acute migraine treatment

Migraine is a common and highly disabling headache disorder associated with a substantial socioeconomic burden. Migraine treatments can be categorized as preventive treatment, aimed at reducing the frequency and severity of migraine attacks, and acute therapy, intended to abort attacks. Traditionally, acute treatment can be classified as specific (ergot derivatives and triptans) or nonspecific (analgesics and nonsteroidal anti-inflammatory drugs). Triptans, a class of 5-HT_1B/1D receptor agonists with some affinity for the 5-HT_1F receptor subtype, have been proven to be efficacious for acute treatment of moderate to severe migraine and have been deemed the gold standard. The availability of triptans in non-oral formulations, such as subcutaneous (SC) and intranasal forms, can be beneficial for patients who suffer from prominent nausea or vomiting, have a suboptimal response to oral agents, and/or seek a more rapid onset of treatment effects. However, triptans are contraindicated in patients with preexisting cardiovascular and/or cerebrovascular diseases due to their 5-HT_1B-mediated vasoconstrictive action. For this reason, studies have focused on the development of ditans, a group of antimigraine drugs targeting 5-HT_1D and 5-HT_1F receptors. Unfortunately, 5-HT_1D receptor agonists have been shown to be ineffective in the acute treatment of migraine. Several ditans targeting the 5-HT_1F receptor have been developed and have shown no vasoconstrictive effect in preclinical studies, but only two of them, lasmiditan and LY334370, have been tested in clinical trials for migraine, and only lasmiditan has reached to Phase III clinical trials. These Phase III trials have demonstrated the efficacy and safety of lasmiditan, a selective 5-HT_1F receptor agonist, in acute migraine treatment. Lasmiditan might offer an alternative migraine therapy without cardiovascular risks. This review will summarize the development of agents targeting the 5-HT_1B/1D and 5-HT_1F receptors and the clinical evidence supporting the use of these agents for acute migraine treatment.

Keywords: 5-HT(1B/1D) receptor; 5-HT(1F) receptor; Acute treatment; Migraine; Serotonin.