Serum CGRP in migraine patients using erenumab as preventive treatment - The Journal of Headache and Pain
Source : https://thejournalofheadacheandpain.biomedcentral.com/articles/10.1186/s10194-022-01483-z
Aim Serum levels of Calcitonin Gene-Related Peptide (CGRP)-like immunoreactivity (CGRP-LI) in migraine patients before and after starting treatment with erenumab were measured to evaluate the association with clinical treatment response. Methods Blood samples were collected from the cubital fossa before (T0) and 2-4 weeks after (T1) starting treatment with erenumab.
Conclusion: Lower serum CGRP-LI 2–4 weeks after starting treatment with erenumab was associated with a higher reduction in migraine days after three months of treatment. Although the underlying mechanisms remain to be determined, this suggests that changes in CGRP levels, shortly after starting erenumab, are important for its clinical effect.
• Source: The Journal of Headache and Pain
• Conclusion: “Lower serum CGRP-LI [Calcitonin Gene-Related Peptide-like immunoreactivity] 2–4 weeks after starting treatment with erenumab was associated with a higher reduction in migraine days after three months of treatment. Although the underlying mechanisms remain to be determined, this suggests that changes in CGRP levels, shortly after starting erenumab, are important for its clinical effect."
• In the study, Dutch researchers treated 96 patients with erenumab 70 mg, with no other prophylactic therapy. Serum CGRP-LI levels were no different between TO and T1 (i.e., 2-4 weeks after injection) even though there was a decrease in monthly migraine days (MMD). Time was related to a decrease in MMD (P = ).
• Previous studies have demonstrated mixed findings of the impact of erenumab on CGRP-LI, with some data suggesting that it may take up to 6 months for levels to be affected.
• The investigators hypothesized the reason why MMD continued to decrease further after the first month of treatment was due to the long half-life of monoclonal antibodies
• One limitation of the current study is that blood was drawn from the antecubital vein, which could result in lower CGRP-LI levels than if it had been collected from the jugular vein. Another limitation was that blood in some patients could have been drawn on headache vs. interictal days.
• The authors wrote the following: “Data from clinical trials and real life data show that not all migraine patients have a successful migraine reduction in response to treatment with anti-CGRP (receptor) antibodies …. It is of utmost importance to increase the understanding of response to anti-CGRP treatment even further and to uncover reasons for (non-)response …. measuring CGRP in patients receiving an anti-CGRP antibody might provide additional information on the expectations of effects of this treatments.”