Sustained response to atogepant in episodic migraine: post hoc analyses of a 12-week randomized trial and a 52-week long-term safety trial

Background Atogepant is an oral calcitonin gene-related peptide receptor antagonist approved for the preventive treatment of migraine in adults. These analyses evaluated the proportions of clinical trial participants who experienced sustained responses to atogepant over 12 or 52 weeks of treatment.Methods These were post hoc analyses of ADVANCE, a 12-week, double-blind, randomized trial of atogepant 10, 30, and 60 mg once daily vs. placebo for the preventive treatment of episodic migraine, and a separate open-label long-term safety (LTS) trial of atogepant 60 mg once daily over 52 weeks. The 60 mg dose of atogepant was used to detect safety issues. An initial response was defined as >= 50%, >= 75%, or 100% reduction from baseline in MMDs in month 1 for ADVANCE or quarter 1 for the LTS trial. The proportions of participants who continued to experience a response above each response-defining threshold through each subsequent month (for ADVANCE) or each quarter (for LTS) were calculated.Results In ADVANCE, sustained response rates during months 2 and 3 varied with dose and were as follows: 70.8-81.1% following an initial >= 50% response, 47.3-61.9% following an initial >= 75% response, and 34.8-41.7% following an initial 100% response. Of those who experienced an initial >= 75% or 100% response during month 1, more than 79% continued to experience at least a 50% response during both months 2 and 3. During the LTS trial, sustained response rates through quarters 2, 3, and 4 were 84.7% following an initial >= 50% response, 72.6% following an initial >= 75% response, and 37.8% following an initial 100% response. Of those who experienced an initial >= 75% or 100% response during quarter 1, more than 90% continued to experience at least a 50% response through quarters 2, 3, and 4.Conclusion Over 70% of participants who experienced an initial response with atogepant treatment had a sustained response with continued treatment.Trial registration ClinicalTrials.gov: NCT03777059 (submitted: December 13, 2018); NCT03700320 (submitted: September 25, 2018).