Early treatment, when pain is mild, is recommended for acute treatment of migraine attacks. LTN, a novel, selective 5-HT_1F receptor agonist, was superior to placebo in treating moderate-to-severe migraine attacks in two phase3 trials. There were few mild attacks studied in the phase3 program.

This analysis assessed data (intent to treat) from a prospective, randomized, open-label, phase 3 study (GLADIATOR [NCT02565186]) in which patients were randomized 1:1 to LTN 100 mg or 200 mg. Efficacy measures included proportion of attacks with 2h pain freedom (PF), 2h most bothersome symptom (MBS) freedom, and 24h sustained pain freedom (SPF). The proportion of patients with PF, SPF, or MBS freedom among mild, moderate, or severe attacks was compared using Fisher’s exact test.

This analysis includes data from 1,981 patients who treated 17,878 migraine attacks. A total of 273 (1.5%), 11,644 (65.1%), and 5,948 (33.3%) attacks were treated when pain was mild, moderate, and severe, respectively. Average (mean) time from headache onset to treatment administration was 1.3h . There was a relative greater proportion of mild attacks with PF vs. moderate and severe attacks (mild:100mg/200mg: 33.6%[50/149]/54.8%[68/124]; oderate:29.7%[1,759/5,931]/36.2%[2,068/5,713]*; severe:17.9% [538/3,012]*/19.4%[571/2,936]*, *p<0.001). Similarly, a higher proportion of mild attacks with SPF and MBS freedom were observed. Overall, ≥1 treatment-emergent adverse event (TEAE) was reported in 16.8%, 14.3%, and 10.2% of mild, moderate, and severe migraine attacks, respectively. The most frequent TEAE was dizziness, irrespective of headache intensity across the attacks.