P028 | WORSENING OF MIGRAINE AFTER DISCONTINUATION OF ANTI-CGRP MONOCLONAL ANTIBODIES: PATIENTS WITHOUT RECURRENCE FOR AT LEAST 6 MONTHS

M. Katsuki^1|2, M. Romozzi^3|4, S. Ooba⁵, Y. Matsumori⁶, K. Moran², T. Ward², S. Ishii⁷ | ¹Nagaoka University of Technology, Japan; ²Insight Research Ireland Centre for Data Analytics, Ireland; ³Università Cattolica del Sacro Cuore, Italy; ⁴Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Italy; ⁵Ooba Clinic for Neurosurgery & Headache, Japan; ⁶Sendai Headache and Neurology Clinic, Japan; ⁷Daidai Clinic Kudanshita Headache Clinic, Japan

Abstract

Background. Monoclonal antibodies targeting CGRP or its receptor are widely used for migraine prevention. However, the optimal timing of treatment discontinuation and the subsequent clinical course remain unclear. This study evaluated the frequency of worsening after discontinuation and associated factors among responders, defined as patients who achieved a ≥50% reduction in monthly headache days (MHD), and who discontinued treatment after shared decision-making.
Methods. We conducted a retrospective analysis at two specialized-headache clinics. Patients with migraine were included if they had received anti-CGRP monoclonal antibodies for at least 3 months, achieved a ≥50% reduction in MHD, discontinued treatment at the patient’s request and in agreement with the physician, and were followed for at least 6 months after discontinuation. The primary endpoint was the proportion of patients with an increase of at least 2 MHD from the final MHD value within 6 months after discontinuation. We also examined potential associated factors, including age, sex, episodic or chronic migraine, treatment duration ≥6 months, pre-treatment MHD, final MHD <4 days, and failure of at least three previous preventive treatments.
Results. Among 1,900 patients treated with anti-CGRP monoclonal antibodies, 75% (1,423/1,900) achieved a ≥50% reduction in MHD. Of these, 24% (335/1,423) discontinued treatment after clinical improvement; 292 patients had at least 6 months of follow-up. Within 6 months after discontinuation, 52% (152/292) showed an increase of at least 2 MHD from the final value, whereas 48% did not experience worsening. The mean time to worsening was 7 months; some patients remained stable for up to 39 months. Treatment duration ≥6 months and final MHD <4 days were associated with a favorable outcome.
Conclusions. In the Japanese clinical setting, the therapeutic effect may persist for at least 6 months after discontinuation in approximately half of patients with migraine who respond to anti-CGRP monoclonal antibodies.