reviewed april 2026|next review october 2026|88 physicians psi has verified|116705 published studies
CGRP (Calcitonin Gene-Related Peptide)
CGRP (calcitonin gene-related peptide) is a 37-amino-acid naturally occurring (the body's own) neuropeptide that is the primary mediator of migraine headache, with four FDA-approved CGRP-targeting drugs (erenumab, fremanezumab, galcanezumab, rimegepant) transforming migraine treatment.
Evidence landscape: 116705 published studies
116,705 published items. 10 human studies and 136 animal studies indexed under this slug. The broader CGRP/migraine literature exceeds 25,000 clinical studies.
- 10 Human
- 136 Animal
- 54 Reviews
- 116505 Other research
CGRP itself is not a drug. Four monoclonal antibodies targeting CGRP or its receptor (erenumab/Aimovig, fremanezumab/Ajovy, galcanezumab/Emgality, eptinezumab/Vyepti) and multiple gepants (rimegepant/Nurtec, ubrogepant/Ubrelvy, atogepant/Qulipta) are FDA-approved for migraine.
CGRP is a naturally occurring (the body's own) neuropeptide. The FDA-approved anti-CGRP drugs are available by prescription. The therapeutic value comes from blocking CGRP, not supplementing it.
One of the most successful peptide-to-drug translation stories in medicine. Decades of basic science identifying CGRP as the primary migraine mediator led to an entirely new drug class.
PSI Assessment
The identification of CGRP as the primary mediator of migraine headache led to one of the most successful targeted drug development programs in neurology. Four separate FDA-approved drugs now target the CGRP pathway: erenumab (Aimovig) blocks the CGRP receptor, fremanezumab (Ajovy) and galcanezumab (Emgality) bind CGRP itself, and rimegepant (Nurtec) is a small-molecule CGRP receptor antagonist. The STRIVE, HALO, and EVOLVE trials each enrolled over 800 patients and demonstrated significant migraine day reduction. With over 116,000 published studies, CGRP illustrates how understanding a single neuropeptide can transform an entire disease category.
Four FDA-approved drugs target CGRP for migraine. The STRIVE, HALO, and EVOLVE trials transformed migraine treatment. Over 116,000 published studies.
The mechanism is CGRP-mediated trigeminovascular activation. During a migraine, CGRP is released from trigeminal sensory neurons, causing vasodilation of intracranial blood vessels, neurogenic inflammation, and central sensitization that produces the characteristic throbbing pain, photophobia, and nausea. Blocking CGRP signaling, either by binding the peptide itself or blocking its receptor, prevents this cascade. The CGRP receptor is a heterodimer of CLR (calcitonin receptor-like receptor) and RAMP1 (receptor activity-modifying protein 1).
What the evidence supports
CGRP is established as the primary mediator of migraine headache through extensive human and animal research. Four FDA-approved drugs targeting the CGRP pathway validate the mechanism. The STRIVE (erenumab), HALO (fremanezumab), and EVOLVE (galcanezumab) Phase III trials each demonstrated significant migraine day reduction in large patient populations. Both preventive (monthly antibody) and acute (oral gepant) treatment modalities are FDA-approved.
What is not yet established
Whether CGRP-targeting drugs are effective for all migraine subtypes. Long-term safety of sustained CGRP pathway blockade (CGRP has physiological roles in cardiovascular protection and wound healing). Comparative effectiveness between the four approved agents. Whether CGRP antagonism has therapeutic potential beyond migraine.
Research Evidence
The findings below cover what decades of CGRP research have established and where the remaining scientific questions lie.
Evidence by condition
Evidence dimensions across CGRP's investigated applications. Migraine prevention and acute treatment are FDA-approved. Cluster headache has Phase III data. Cardiovascular regulation is an active research area.
| Condition | Mechanism | Animal evidence | Human evidence | Replication |
|---|---|---|---|---|
| Migraine Prevention | ||||
| Migraine Acute Treatment | ||||
| Cluster Headache | ||||
| Vasodilation Research |
CGRP is established as the primary mediator of migraine headache. Four FDA-approved monoclonal antibodies and multiple small-molecule gepants target this pathway, validating it as one of the strongest therapeutic targets in neuroscience.
The pathway is no longer debated. The remaining question is optimization of treatment, not validation of the target.
The STRIVE (erenumab), HALO (fremanezumab), and EVOLVE (galcanezumab) Phase III trials each enrolled over 800 patients and demonstrated significant migraine day reduction. Both preventive and acute treatment modalities are FDA-approved.
Approximately 50-60% of patients achieve at least 50% reduction in monthly migraine days. The mechanism of non-response in the remaining patients is not fully understood.
CGRP has physiological roles beyond migraine, including cardiovascular protection through potent vasodilation. The long-term effects of chronic CGRP pathway blockade on cardiovascular health are an active area of investigation.
Post-marketing surveillance of anti-CGRP drugs has not identified major cardiovascular safety signals, but long-term data continues to accumulate.
10 Human|136 Animal|54 Reviews
View all 116705 indexed studiesHow CGRP (Calcitonin Gene-Related Peptide) Works
CGRP is a 37-amino-acid naturally occurring (the body's own) neuropeptide widely distributed in the central and peripheral nervous systems, and one of the most potent vasodilators known.
CGRP is released by nerve endings around the brain's blood vessels. When too much CGRP is released, those vessels swell, the surrounding tissue becomes inflamed, and pain signals fire, producing a migraine. Anti-CGRP drugs work by either neutralizing the CGRP molecule itself (antibodies) or blocking the receptor it attaches to (gepants), preventing this cascade.
For a more detailed view of the biology, here is what researchers have observed at the molecular level.
CGRP is a 37-amino acid neuropeptide that signals through a heterodimeric receptor complex of calcitonin receptor-like receptor (CLR) and receptor activity-modifying protein 1 (RAMP1). In migraine, CGRP is released from trigeminal sensory neurons, causing meningeal vasodilation, mast cell degranulation, neurogenic inflammation, and peripheral and central sensitization of pain pathways. It also has potent cardiovascular vasodilatory functions throughout the body.
What is CGRP (Calcitonin Gene-Related Peptide) being studied for?
Researchers are studying CGRP (Calcitonin Gene-Related Peptide) across several health conditions. Each condition below is labeled with the strength of evidence that exists for that specific use, not for CGRP (Calcitonin Gene-Related Peptide) overall. This means a compound can have human studies for one condition but only animal data for another.
Migraine Prevention
·FDA ApprovedFour monoclonal antibodies targeting CGRP or its receptor are FDA-approved for migraine prevention. They reduce monthly migraine days by 50% or more in approximately 50-60% of patients.
Limitations: Not all patients respond. Cost remains a barrier. The mechanism of non-response is not fully understood.
Migraine Acute Treatment
·FDA ApprovedSmall-molecule CGRP receptor antagonists (gepants: rimegepant, ubrogepant, atogepant) are FDA-approved for acute migraine treatment and prevention.
Limitations: Not all migraines respond to gepants. Whether gepants are superior to triptans for specific migraine subtypes is not fully established.
Cluster Headache
·Human TrialsGalcanezumab (Emgality) is FDA-approved for episodic cluster headache prevention, the first and only FDA-approved preventive for this condition.
Limitations: Efficacy for chronic cluster headache has not been demonstrated. The cluster headache population is much smaller than migraine, limiting study sizes.
Vasodilation Research
·Animal StudiesCGRP is one of the most potent vasodilators known. It plays protective roles in cardiovascular function, raising the question of what chronic blockade means for heart and vascular health.
Limitations: Long-term cardiovascular effects of chronic CGRP blockade have not been fully characterized. Post-marketing surveillance is ongoing.
Safety and Regulatory Status
FDA Status: CGRP itself is not a drug. Multiple anti-CGRP drugs are FDA-approved for migraine prevention and treatment (erenumab, fremanezumab, galcanezumab, eptinezumab, rimegepant, ubrogepant, atogepant).
Availability: Naturally occurring (the body's own) neuropeptide. The FDA-approved anti-CGRP drugs are available by prescription.
Class context: Anti-CGRP drugs have generally favorable safety profiles. Most common side effects: constipation and injection site reactions (antibodies), nausea (gepants). The main open question is long-term cardiovascular safety of chronic CGRP blockade.
CGRP itself is a naturally occurring (the body's own) neuropeptide. The safety discussion centers on anti-CGRP drugs that block it. These FDA-approved therapies have generally favorable safety profiles. The most common side effects are constipation and injection site reactions for antibodies, and nausea for gepants. The main open question is long-term cardiovascular safety, since CGRP serves protective vasodilatory functions. Post-marketing surveillance has not identified major safety signals to date.
Questions and Comparisons
Questions the evidence raises for a CGRP (Calcitonin Gene-Related Peptide) discussion.
Comparison and Related Research
CGRP is most often compared with other pain-signaling neuropeptides and migraine treatment approaches.
Related compounds
Frequently Asked Questions
References
Each citation links to the original study on PubMed, the U.S. National Library of Medicine database.
- 1.The STRIVE trial, a landmark Phase 3 study that helped establish CGRP-targeting therapy as a validated migraine prevention strategy. Erenumab, a monoclonal antibody that blocks the CGRP receptor, significantly reduced monthly migraine days compared to placebo in adults with episodic migraine. This trial was central to FDA approval and represented the first monoclonal antibody specifically developed for migraine prevention.Goadsby PJ et al., 2017 in N Engl J Med. View on PubMed
- 2.Phase 3 trial evaluating fremanezumab, a monoclonal antibody that binds CGRP directly (rather than its receptor), for prevention of episodic migraine. Both monthly and quarterly dosing schedules significantly reduced migraine frequency, providing an additional therapeutic option targeting the CGRP pathway with a different molecular approach than receptor blockade.Dodick DW et al., 2018 in JAMA. View on PubMed
- 3.The EVOLVE-1 Phase 3 trial evaluating galcanezumab, another anti-CGRP monoclonal antibody, for episodic migraine prevention. Treatment significantly reduced monthly migraine headache days compared to placebo, with response rates supporting clinically meaningful benefit. The convergence of positive results across multiple anti-CGRP antibodies confirmed that CGRP plays a central role in migraine pathophysiology.Stauffer VL et al., 2018 in JAMA Neurol. View on PubMed
- 4.Comprehensive review of CGRP biology, covering its role as both a vasodilator in normal cardiovascular function and a key mediator in pain signaling and migraine pathophysiology. The review explains how CGRP is released from trigeminal sensory neurons during migraine attacks, activating receptors on meningeal blood vessels and second-order neurons to propagate the pain signal. This foundational biology underpins all current anti-CGRP therapeutic strategies.Russell FA et al., 2014 in Physiol Rev. View on PubMed
Medical Disclaimer
This content is for educational and informational purposes only and does not constitute medical advice. The information presented reflects published research as indexed by PSI and should not be used to make treatment decisions. Always consult a qualified healthcare provider before starting, stopping, or modifying any treatment.