A meta-analysis of 11 RCTs with 4,402 patients confirms that anti-CGRP monoclonal antibodies reduce monthly migraine days by 1.44 days and are 51% more likely to achieve a 50% response rate versus placebo.
51% higher 50% response ratePatients receiving anti-CGRP antibodies were 51% more likely to achieve at least a 50% reduction in monthly migraine days compared to placebo across 11 RCTs
What the researchers found
Across 11 high-quality RCTs (n=4,402), compared to placebo:
- Monthly migraine days reduced by 1.44 days (WMD: -1.44; 95% CI: -1.68 to -1.19)
- Acute migraine-specific medication days reduced by 1.28 days (WMD: -1.28; 95% CI: -1.66 to -0.90)
- 50% responder rate improved by 51% (RR: 1.51; 95% CI: 1.37 to 1.66)
- Adverse events and withdrawal rates due to AEs were not significantly different from placebo
- Subgroup analysis showed similar efficacy and safety for erenumab, fremanezumab, and galcanezumab individually
Why it matters
This meta-analysis provides high-level evidence confirming that blocking the CGRP peptide pathway is an effective migraine prevention strategy. For the millions of people whose migraines don't respond well to conventional preventive drugs, anti-CGRP antibodies represent a targeted, evidence-based alternative with a favorable safety profile.
How the study worked
A systematic review and meta-analysis of 11 randomized controlled trials identified through electronic database searches. Two independent authors extracted data and assessed quality. Mean differences were calculated for continuous outcomes and risk ratios for dichotomous outcomes. Subgroup analyses were performed for each individual anti-CGRP antibody.
What this study cannot tell us
The follow-up periods in most included trials were relatively short (typically 3–6 months), so long-term efficacy and safety data are limited. The studies focused on episodic migraine, so results may not apply to chronic migraine. The pooled reduction of ~1.4 migraine days per month is statistically significant but may seem modest at an individual level, though the 50% responder rate provides a more clinically meaningful measure.
How to read the evidence
This is a systematic review and meta-analysis of 11 randomized controlled trials, representing the highest level of clinical evidence. The included studies were assessed as high quality, and the results are consistent across individual antibodies.
When this study was published
Published in 2020, this meta-analysis captured the early RCT evidence for anti-CGRP antibodies. Since then, additional real-world data and longer-term studies have further supported these findings.
The bigger picture
Anti-CGRP antibodies were the first migraine-specific preventive treatments, marking a paradigm shift from repurposed drugs (beta-blockers, anticonvulsants) to targeted therapies based on migraine biology. This meta-analysis helped establish the evidence base that led to widespread adoption of these treatments and paved the way for newer CGRP pathway targets including small-molecule CGRP receptor antagonists (gepants).
Questions still open
- How do anti-CGRP antibodies compare to conventional migraine preventives like topiramate or propranolol in head-to-head trials?
- Do anti-CGRP antibodies maintain their efficacy over years of continuous use?
- Can combining anti-CGRP antibodies with other preventive treatments provide additional benefit for treatment-resistant patients?
Common questions
How well do anti-CGRP antibodies work for migraines?
Are all three anti-CGRP antibodies equally effective?
Read the original research
Efficacy and safety of calcitonin-gene-related peptide binding monoclonal antibodies for the preventive treatment of episodic migraine - an updated systematic review and meta-analysis.
BMC neurology, 20(1), 57
Citation
Deng, Hong; Li, Gai-Gai; Nie, Hao; Feng, Yang-Yang; Guo, Guang-Yu; Guo, Wen-Liang; Tang, Zhou-Ping. (2020). Efficacy and safety of calcitonin-gene-related peptide binding monoclonal antibodies for the preventive treatment of episodic migraine - an updated systematic review and meta-analysis.. BMC neurology, 20(1), 57. https://doi.org/10.1186/s12883-020-01633-3