Switching between anti-calcitonin gene-related peptide monoclonal antibodies: A comparison of monthly and quarterly dosing

Background: Anti-calcitonin gene-related peptide monoclonal antibodies (CGRPmAbs) have dramatically changed preventive treatment options for patients with migraine. Although there is emerging real-world evi-dence on the use of CGRPmAbs globally, the change in efficacy and safety after switching between CGRPmAbs owing to patients' frequency of hospital visits preference remains unknown.Methods: We conducted a single-centre, retrospective, real-world study of patients with migraine who first received galcanezumab for 3 or 4 months and then switched to fremanezumab at Keio University Hospital. We investigated changes in monthly migraine days (MMD), responder rate, and adverse effects such as injection site reactions.Results: MMD increased only by 0.7 (95% CI, -4.1-5.5; p = 0.748) after 4 months of treatment with fremane-zumab (6.1, 95% CI, 2.3-9.9) compared to before switching (5.4, 95% CI, 2.2-8.6). Furthermore, switching from galcanezumab to fremanezumab produced only minor adverse events, such as injection site reactions.Conclusions: After switching from galcanezumab to fremanezumab out of the desire to visit the hospital less often, the reduction in MMD compared to baseline was sustained, and no serious adverse effects were observed.