Monoclonal antibodies against calcitonin gene-related peptide in chronic migraine: an adjusted indirect treatment comparison

Abstract

ObjectiveNew monoclonal antibodies against the calcitonin generelated peptide pathway have recently been developed for the prevention of migraine. The aim of this study is to compare the efficacy of monoclonal antibodies against the calcitonin generelated peptide pathway drugs in chronic migraine through an adjusted indirect treatment comparison, and to establish whether they can be considered equivalent therapeutic alternatives in this pathology. MethodA bibliographic search of randomized clinical trials was performed in PubMed database on December 26, 2019. The inclusion criteria were phase II/III randomized clinical trials of monoclonal antibodies against the calcitonin generelated peptide pathway with similar population, length of follow-up and treatment comparator. The reduction of at least 50% migraine-days/month was selected as efficacy endpoint. Chronic migraine was defined as > 15 headache days/month, of which > 8 were migraine-days (event duration > 4 hours). Randomized clinical trials with different clinical chronic migraine context and definition of disease were excluded. An indirect treatment comparison was developed using Bucher's method. The equivalent therapeutic alternatives positioning guide was used for the evaluation of potentially equivalent alternatives. Delta value (A, maximum difference as clinical criterion of equivalence) was calculated as half of absolute risk reduction obtained in a meta-analysis of randomized clinical trials included in indirect treatment comparison. ResultsThirty randomized clinical trials were found: erenumab (n = 12), fremanezumab (n = 7), galcanezumab (n = 10) and eptinezumab (n = 1). Three studies were selected: one of erenumab, one of fremanezumab and another of eptinezumab. The rest were not included in indirect treatment comparison for non-compliance of inclusion criteria. Results of indirect treatment comparison among different regimens of studied drugs showed no statistically significant differences, and the most part of 95% confidence interval was within calculated delta margins (A = 9.5%). No relevant safety differences among the three drugs were found. ConclusionsIndirect treatment comparison showed no statistically significant differences in reduction of > 50% migraine days/month between erenumab, fremanezumab and eptinezumab. Probable clinical equivalence was found between these drugs in terms of efficacy and safety, therefore they could be considered equivalent therapeutic alternatives in chronic migraine.