Effect of single dose Erenumab on cortical responses evoked by cutaneous a-delta fibers: A pilot study in migraine patients

Background: Erenumab is a monoclonal antibody against calcitonin gene-related peptide receptors, which showed efficacy in migraine attack prevention. The aims of the present pilot study were to i) evaluate the effect of single dose of Erenumab 70 mg on laser evoked potentials from trigeminal and brachial stimulation in a cohort of migraine patients; ii) correlate the neurophysiological changes with clinical outcome after 3 months’ treatment. Methods: Laser evoked potentials were recorded by 61 electroencephalogram channels before (T0), 1 h (T1) and 7 days after (T2) Erenumab 70 mg injection, stimulating the left and right forehead and the right hand. Laser evoked potential control 1 h after the injection served as placebo session. Results: Seventeen migraine patients were evaluated. The N1 and N2 component obtained from the right and left trigeminal stimulation diminished in amplitude at T2, compared to T0 and T1 conditions. N2 habituation reduction slightly recovered at T2. Laser evoked potential changes did not correlate with clinical improvement after 3 months of Erenumab treatment. Conclusions: A single dose of Erenumab has a mild inhibitory effect on cortical responses evoked from trigeminal cutaneous a-delta fibers. Though this phenomenon was not predictive of the clinical outcome, it confirms a wide representation of calcitonin gene-related peptide receptors on trigeminal afferents.