Migraine affects millions of people worldwide, often disrupting daily life with intense pain, nausea, and sensitivity to light and sound.

While acute treatments can relieve symptoms during attacks, many patients benefit from preventive therapies. Fremanezumab (brand name Ajovy) and Galcanezumab (brand name Emgality) are two FDA-approved medications that have revolutionized migraine prevention.

Both drugs belong to a new class of treatments known as CGRP monoclonal antibodies, designed to reduce migraine frequency and severity. Understanding the similarities and differences between Fremanezumab and Galcanezumab can help patients and healthcare providers make informed treatment decisions.

What Are CGRP Inhibitors?

CGRP (calcitonin gene-related peptide) is a protein involved in the transmission of migraine pain and the dilation of blood vessels in the brain. During a migraine attack, CGRP levels increase, which is believed to play a major role in triggering symptoms.

CGRP monoclonal antibodies like Fremanezumab and Galcanezumab work by blocking the CGRP pathway, preventing it from causing inflammation and pain.

Fremanezumab (Ajovy)



  • Manufacturer: Teva Pharmaceuticals




  • FDA Approval: 2018




  • Indications: Preventive treatment of episodic and chronic migraine in adults




  • Dosing Options:



    • 225 mg once monthly




    • 675 mg every 3 months (quarterly injection)






  • Administration: Subcutaneous injection, self-administered




  • Mechanism: Binds directly to CGRP ligand to prevent it from activating receptors



Galcanezumab (Emgality)



  • Manufacturer: Eli Lilly and Company




  • FDA Approval: 2018




  • Indications:



    • Preventive treatment of migraine in adults




    • Treatment of episodic cluster headache






  • Dosing for Migraine:



    • Loading dose: 240 mg (two injections of 120 mg)




    • Maintenance: 120 mg once monthly






  • Administration: Subcutaneous injection, self-administered




  • Mechanism: Binds to CGRP ligand to block its activity



Key Similarities



  • Both drugs are preventive therapies for migraine, not for acute attack relief.




  • They are injectable monoclonal antibodies targeting CGRP.




  • Both are given subcutaneously, typically in the abdomen, thigh, or upper arm.




  • Well-tolerated by most patients with a low risk of serious side effects.




  • Can be self-injected at home using prefilled syringes or autoinjectors.



Main Differences































Feature Fremanezumab (Ajovy) Galcanezumab (Emgality)
Dosing Frequency Monthly or quarterly Monthly only
FDA Cluster Headache Use No Yes (episodic only)
Loading Dose Required No Yes (240 mg first dose)
Manufacturer Teva Pharmaceuticals Eli Lilly and Company

 

Efficacy

Both drugs have shown effectiveness in reducing monthly migraine days (MMDs) in clinical trials. Some patients experience relief as early as 1 month after starting treatment, with continued improvement over time.



  • Fremanezumab is especially convenient for those who prefer less frequent dosing.




  • Galcanezumab is beneficial for patients who also suffer from episodic cluster headaches, as it is approved for both conditions.



Side Effects

The side effects are generally mild and may include:



  • Injection site reactions (pain, redness, itching)




  • Constipation (more common with Galcanezumab)




  • Hypersensitivity or allergic reactions (rare)




  • Fatigue or muscle pain (uncommon)



No significant drug interactions have been noted, and both are considered safe for long-term use under medical supervision.

Who Should Consider These Treatments?

Fremanezumab or Galcanezumab may be suitable for patients who:



  • Experience frequent or debilitating migraines




  • Have failed multiple oral preventive medications (e.g., beta-blockers, anticonvulsants)




  • Prefer a non-daily preventive treatment




  • Need improved migraine control with fewer side effects



They may not be appropriate for those with a history of severe allergic reactions to injectable medications or with certain cardiovascular risks (as CGRP is involved in blood vessel regulation).

Access and Cost Considerations

Both medications are prescription-only and may be covered by insurance if criteria for preventive treatment are met. Manufacturers often offer copay cards, savings programs, and patient assistance for eligible individuals.



  • Teva offers the Ajovy Copay Savings Program




  • Eli Lilly offers Emgality Savings Card and Support Services



Out-of-pocket prices without insurance or discounts can be over $600–$700 per injection, highlighting the importance of using support programs.

Conclusion

Fremanezumab and Galcanezumab represent significant progress in migraine prevention, offering long-term relief with minimal daily effort. While both target the same migraine pathway, the differences in dosing, indications, and administration may influence the choice of therapy.

Discussing these options with your healthcare provider can help determine which medication best aligns with your migraine pattern, lifestyle, and treatment goals.