Section 02 · Monograph

Galcanezumab

Reviewed Nov 2026FDA label

EmgalityCGRP mAb · injectable

Indications

Humanized IgG4 monoclonal antibody directed against calcitonin gene-related peptide (CGRP)
Binds CGRP ligand and blocks its binding to the CGRP receptor
CGRP and its receptors are expressed on sensory neurons and are implicated in the pathophysiology of migraine
Not metabolized by cytochrome P450 enzymes; cleared by general protein catabolism like endogenous IgG

Migraine prevention: 240 mg loading dose (two consecutive 120 mg subcutaneous injections) on Day 1, then 120 mg subcutaneously once monthly
Episodic cluster headache: 300 mg (three consecutive 100 mg subcutaneous injections) at onset of the cluster period, then 300 mg monthly until the cluster period ends
Available as single-dose prefilled syringe, single-dose prefilled pen, or single-dose vial
Inject subcutaneously into the abdomen, thigh, back of the upper arm, or buttocks; rotate injection sites
Allow refrigerated product to warm at room temperature for 30 minutes before injecting; do not use external heat sources to warm it

Serious hypersensitivity to galcanezumab-gnlm or any excipient in the formulation

No clinically significant drug-drug interactions anticipated because galcanezumab is not metabolized by CYP450 enzymes
No formal drug interaction studies have been conducted
Concurrent use with other CGRP-pathway-targeted therapies (e.g., other anti-CGRP antibodies, gepants) has not been studied

Injection site reactions — most common adverse reaction (~18% vs 13% placebo)
Hypersensitivity reactions: rash, urticaria, dyspnea, anaphylaxis, angioedema; can occur days after administration and may be prolonged
Constipation, including serious cases requiring hospitalization or surgery
New-onset or worsening hypertension, most commonly within 7 days of dosing
Raynaud's phenomenon (new-onset or worsening), median onset ~71 days after dosing

Observe for hypersensitivity reactions during and in the days following each dose
Monitor blood pressure, particularly during the first week after dosing
Assess bowel function and evaluate for severe or worsening constipation
Screen for Raynaud's phenomenon symptoms (digital color change, pain), especially in patients with a prior history
Periodically reassess ongoing efficacy (e.g., headache diary) to justify continued therapy

A pregnancy exposure registry monitors outcomes in women exposed to EMGALITY during pregnancy (1-833-464-4724)
Animal reproduction studies showed no adverse developmental effects at exposures exceeding clinical doses
No adequate data on developmental risk associated with use in human pregnancy
No data on presence in human milk, effects on the breastfed infant, or effects on milk production