OnabotulinumtoxinA Add-On to Monoclonal Anti-CGRP Antibodies in Treatment-Refractory Chronic Migraine

We sought to assess the effectiveness of combining dual therapy with onabotulinumtoxinA (BTX) add-on to anti-calcitonin gene-related peptide (CGRP) monoclonal antibodies (anti-CGRP MAbs) in treatment-refractory patients with chronic migraine (CM). We retrospectively reviewed the medical files of 19 treatment-refractory patients with CM who had failed to two oral migraine preventatives, at least three consecutive BTX cycles (less than 30% response rate), at least three consecutive sessions with either fremanezumab or erenumab (less than 30% response rate), and were eventually switched to dual therapy with BTX add-on to any of the already-given anti-CGRP MAbs. We then assessed from baseline to each monotherapy or dual intervention predefined efficacy follow-up the changes in the following efficacy outcomes: (i) monthly headache days (MHD), (ii) monthly days with moderate/severe peak headache intensity, and (iii) monthly days with intake of any acute headache medication. Response (50% reduction in MHD) rates, safety, and tolerability were also determined. In the majority of cases (n = 14), dual targeting proved effective and was associated with clinically meaningful improvement in all efficacy variables; 50% response rates (also disability and QOL outcomes) coupled with favorable safety/tolerability. Our results advocate in favor of the view that dual therapy is effective and should be considered in difficult-to-treat CM patients who have failed all available monotherapies.

Automated summary

This study aimed to evaluate the effectiveness of combining dual therapy with BTX and anti-CGRP MAbs in treatment-refractory CM patients. Retrospective review of medical files of 19 patients showed that dual therapy was effective and associated with significant clinical improvement in the majority of cases, with favorable safety and tolerability.