Onabotulinumtoxin A for the Treatment of Post-Traumatic Headache: Is It Better than Anti-CGRP Antibodies?

Abstract

Post-traumatic headache (PTH) is a common and debilitating consequence of traumatic brain injury (TBI), often resembling migraine and tension-type headaches. Despite its prevalence, the optimal treatment for PTH remains unclear, with current strategies largely extrapolated from other headache disorders. This review evaluates the use of onabotulinumtoxin A (ONA) and anti-calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs) in the treatment of PTH. A comprehensive literature search was conducted on PubMed, including studies published up to September 2024, focusing on the efficacy, safety, and mechanisms of onabotulinumtoxin A and anti-CGRP mAbs in PTH. Both clinical trials and observational studies were reviewed. ONA, widely recognized for its efficacy in chronic migraine, has shown limited benefits in PTH with only one trial involving abobotulinumtoxin A in a cohort of 40 subjects. A phase 2 trial with fremanezumab, an anti-CGRP monoclonal antibody, failed to demonstrate significant efficacy in PTH, raising questions about the utility of targeting CGRP in this condition. ONA may offer advantages over anti-CGRP mAbs, not only in terms of its broader mechanism of action but also in cost-effectiveness and higher patient adherence. Both ONA and anti-CGRP mAbs are potential options for the management of PTH, but the current evidence is insufficient to establish clear guidelines. The negative results from the fremanezumab trial suggest that CGRP inhibition may not be sufficient for treating PTH, whereas onabotulinumtoxin A's ability to target multiple pain pathways may make it a more promising candidate.