Could Symptom Severity Predict the Response to Anti-Cgrp Monoclonal Antibodies in Migraine?

Abstract text (incl. figure legends and references)
Introduction- Little is known about predictors of response to monoclonal antibodies against CGRP and its receptor (anti-CGRP/r) in migraine patients. This study aims to find a clinical responsiveness predictor. Methods- Prospective cohort study of migraine patients treated with anti-CGRP galcanezumab or anti-CGRPr erenumab with 6 months of follow-up at a Headache Clinic of a third level hospital. Symptoms severity was assessed using the Migraine Severity Symptom Score (MSSS). MIDAS and HIT-6 were used for disability assessment. The primary endpoint was the responder rate (RR, defined as ≥50% monthly headache days decrease after 6 months). Exploratory stepwise multiple logistic regression analysis was used for independent predictors of response identification. Results- 126 patients were recruited. Diagnosis was chronic migraine in 75.4% (95/126) and high frequency episodic migraine in 24.6% (31/126). Baseline monthly headache days, MIDAS and HIT-6 had a mean (SD) of 20.2 (7.2), 75.0 (63.0) and 65.8 (8.5) respectively. After 6 months, the RR was 61.1% (77/126) and monthly headache days, MIDAS and HIT-6 showed a decrease of 9.4 (10.2), 40.1 (61.3) and 9.1 (13.4) respectively. Responder status was associated with MSSS total score (OR 0.87, standard error 0.06, B= -0.613, p=0.015) and severity of worsening pain intensity with usual activities (OR 0.54, standard error 0.24, B= -0.140, p=0.012). Conclusion- Among the clinical features, worsening with activities severity could be a predictor of response to anti-CGRP/r monoclonal antibodies. These therapies are effective showing frequent but mild AE in real clinical practice.