Abstract text (incl. figure legends and references)

Objective:To evaluate proportion of participants who sustained initial responses of ≥50%, ≥75%, or 100% reduction in mean monthly migraine days (MMDs) over 12 and 52-weeks of atogepant treatment for episodic migraine.

Methods:Post-hoc analyses of 2 phase 3 trials: ADVANCE (NCT03777059), 12-week placebo-controlled trial of atogepant (10, 30, 60mg); and a separate 52-week open-label, long-term safety (LTS) trial (NCT03700320) of 60mg atogepant. Participants had initial response if they achieved ≥50% reduction from baseline in MMDs in month 1 (4 weeks) for ADVANCE or quarter 1 (3-month average) for the LTS trial. Participants achieving initial response were categorized by response threshold (≥50%, ≥75%, 100%). Proportion of participants sustaining the same initial response or ≥50% through each subsequent month, or quarter, was calculated.

Results:In ADVANCE (Table 1), 70.8–81.1% of participants who achieved a response of ≥50% in MMDs in month 1 sustained their response (ie, a ≥50% response in month 2 and 3) throughout the treatment period. Between 47.3–61.9% of those who were ≥75% responders in month 1 sustained their response, while 79.2–86.9% maintained ≥50% response in month 2 and 3. Of participants achieving initial 100% treatment response, 34.8–41.7% remained migraine-free over 3 months (86.4–95.0% sustained responses of ≥50%, and 66.7–69.6% sustained responses of ≥75%). During the LTS trial (Table 2), 84.7%, 72.6%, and 42.2% of participants who achieved an initial response of ≥50%, ≥75%, or 100% in quarter 1, sustained these responses through quarter 2, 3, and 4. Of those who were initial ≥75% and 100% responders, >90% maintained ≥50% response in each subsequent quarter. Few participants with initial response were non-responders (<25% reduction in MMD) at the end of ADVANCE or LTS trials.

Conclusion:Findings demonstrate the majority of participants who achieved initial atogepant treatment response sustained it with continued treatment over a 52-week period.