Once-Monthly Injectable Medications for Migraine Prevention Starting with "A"
Aimovig (erenumab) is the once-monthly injectable medication starting with "A" that is strongly recommended as a first-line preventive treatment for both episodic and chronic migraine in adults. 1
CGRP Monoclonal Antibodies for Migraine Prevention
Aimovig belongs to a class of medications called calcitonin gene-related peptide (CGRP) receptor antagonists. It works by blocking the CGRP receptor, which plays a key role in migraine pathophysiology.
The 2023 VA/DoD clinical practice guidelines provide a "strong for" recommendation for erenumab (Aimovig) for the prevention of both episodic and chronic migraine, based on high-quality evidence 1. This represents an upgrade from previous guidelines, reflecting the growing body of evidence supporting its efficacy.
Key Features of Aimovig (erenumab):
- Administration: Subcutaneous injection once monthly
- Available Dosages: 70mg or 140mg
- Administration Sites: Abdomen, thigh, or upper arm 2
- Efficacy: Reduces monthly migraine days by 1.4-1.9 days compared to placebo 2
- Responder Rate: 43-50% of patients achieve ≥50% reduction in monthly migraine days (compared to 26.6% with placebo) 2
Clinical Evidence for Aimovig
The FDA approval of Aimovig was based on clinical trials showing significant reductions in monthly migraine days. In pivotal studies, patients receiving Aimovig experienced:
- Reduction of 3.2-3.7 monthly migraine days (vs 1.8 days with placebo)
- 43-50% of patients achieved at least 50% reduction in monthly migraine days
- Significant reduction in acute migraine-specific medication use 2
Aimovig has demonstrated efficacy even in difficult-to-treat populations. In the LIBERTY trial, 30% of patients with episodic migraine who had previously failed 2-4 preventive treatments achieved ≥50% reduction in monthly migraine days (compared to 14% with placebo) 3.
Other "A" Medications for Migraine Prevention
While Aimovig is the primary once-monthly injectable medication starting with "A", there is another CGRP monoclonal antibody that starts with "A":
- Ajovy (fremanezumab): Also strongly recommended for migraine prevention, administered monthly or quarterly 1
Practical Considerations
Dosing Strategy:
- Start with 70mg once monthly
- Some patients may benefit from increasing to 140mg once monthly if response is inadequate 2
- Can be scheduled at any time during the month, including on the day of injection 1
Safety Profile:
- Most common adverse effects: injection site reactions and constipation 2
- Potential for development or worsening of hypertension (added to warnings and precautions) 1
- Generally well-tolerated with similar adverse event profile to placebo in clinical trials 3, 4
Contraindications:
- Serious hypersensitivity to erenumab or any excipients 2
Monitoring and Expectations
- Clinical improvement is often seen within the first month of treatment 5
- Maximum benefit typically achieved after the second injection 5
- Efficacy maintained at 12 months in real-world studies 5
- Regular monitoring for constipation and hypertension is recommended 2
Patient Selection Considerations
Aimovig may be particularly beneficial for:
- Patients with both episodic and chronic migraine 1, 6
- Those who have failed previous preventive treatments 3
- Patients with episodic migraine with pain-free periods (better response than those with continuous pain) 5
Aimovig is less effective in patients with continuous headache pain, with only 13% achieving a 50% response rate compared to 58% in those with pain-free periods 5.
In conclusion, Aimovig (erenumab) is the once-monthly injectable medication starting with "A" that has strong evidence supporting its use for migraine prevention, with a favorable efficacy and safety profile even in patients who have failed other preventive treatments.