BACKGROUND: Calcitonin gene-related peptide (CGRP) (receptor) antibodies 
(erenumab, fremanezumab and galcanezumab) are increasingly used in prophylactic 
treatment of migraine. In the approval studies, severely affected patients with 
migraine and chronic daily headache without any headache free days were 
excluded. Thus, less is known about the effectiveness of CGRP antibody treatment 
in this cohort.
METHODS: Clinical routine data of 32 patients with migraine and daily headache 
were analysed after three months of treatment with a CGRP antibody (16 erenumab, 
7 galcanezumab, 9 fremanezumab), including changes of monthly headache days 
(MHD) monthly migraine days (MMD) and monthly acute medication intake (AMD) as 
well as migraine characteristics. Statistical analysis was performed with the 
Wilcoxon-Test. Migraine characteristics were analysed descriptively.
RESULTS: The number of MHD was significantly reduced (mean reduction (standard 
error), p-value): (-4.2 (1.3), p = 0.009) as well as MMD (-4.3 (1.6), 
p = 0.033). Four patients (13 %) reached a 50 % reduction regarding MHD and 8 
patients (25 %) regarding MMD, migraine duration and intensity improved under 
therapy.
CONCLUSIONS: Despite the low responder rate, CGRP antibodies can be effective at 
least in a few cases of severely affected patients with drug resistant migraine 
and chronic daily headache.
TRIAL REGISTRATION: Retrospective registered.