Better Benefit-to-Risk Ratio for Anti-CGRP mAbs Than Current Migraine Preventive Medication

The researchers compared anti-CGRP mAbs with other drugs for the prevention of episodic and chronic migraine using a likelihood to help versus harm analysis.

Monoclonal antibodies targeting the calcitonin gene-related peptide pathway (anti-CGRP mAbs) exhibit a more favorable benefit-to-risk ratio than established treatments for preventing episodic and chronic migraine, according to the results of a study published in Cephalalgia.

Although previous research has demonstrated the efficacy of anti-CGRP mAbs in randomized clinical trials in the prevention of episodic and chronic migraine, the benefit-to-risk ratio of this treatment method has not been directly compared with existing therapies.

To assess anti-CGRP mAb treatment relative to established treatments, data from 20 peer-reviewed articles published between 2000 and 2020 were analyzed. The benefit-to-risk ratio of anti-CGRP mAbs was compared with that of topiramate and propranolol in the prevention of episodic migraine (EM) and with that of topiramate and onabotulinumtoxinA in the prevention of chronic migraine (CM).

The number of patients required to be treated for a patient to achieve a 50% or greater reduction in migraine days (NNTB50%) was used as an effect size metric of efficacy. The number of patients required to be treated for a patient to experience an adverse event that resulted in treatment discontinuation (NNTHD-AE) was used as a measure of risk.

All treatments demonstrated a greater likelihood to help than harm (LHH), with the exception of a 200-mg daily dose of topiramate. The NNTB for topiramate and propranolol were similar for both EM and CM.

Though LHH values varied greatly for all migraine treatments, anti-CGRP mAbs had slightly more advantageous NNTB50% values for EM as well as CM. Fremanezumab had the highest benefit-to-risk ratio for EM, and galcanezumab had the highest benefit-to-risk ratio for CM.

In CM trials, the NNTHD-AE of anti-CGRP mAbs varied from 58 to 25,854 compared with 11 for propranolol. In EM trials, the NNTHD-AE of anti-CGRP mAbs varied from 36 to 8527 compared with from 13 to 21 for topiramate and 38 for onabotulinumtoxinA.

Taken together, the results of this study indicated that anti-CGRP mAbs have a slightly favorable benefit-to-risk profile compared with established treatments for the prevention of migraines. The higher NNTHD-AE values for anti-CGRP mAbs compared with established treatments may indicate a greater likelihood for adherence to the treatment, which has been shown to be a common cause for migraine management failure.

Limitations to this study include the heterogeneity across included studies, which prevented the pooling of data for more robust analysis.

Future research using a head-to-head trial design is warranted to support the findings of this study.

Disclosure: Some study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.


Drellia K, Kokoti L, Deligianni CI, Papadopoulos D, Mitsikostas DD. Anti-CGRP monoclonal antibodies for migraine prevention: a systematic review and likelihood to help or harm analysis. Cephalalgia. Published online February 10, 2021. doi:10.1177/0333102421989601