What is the best course of action for a patient with chronic migraine (CM) on erenumab (aimovig) 70 mg monthly, who has noticed an increase in blood pressure readings, despite initial benefit from the medication?

Management of Hypertension in a Patient on Erenumab for Chronic Migraine

The best recommendation for this patient is to change erenumab to atogepant 60 mg daily due to the known risk of hypertension with erenumab and the need to control both migraine and blood pressure. 1, 2

Assessment of Current Situation

The patient presents with:

• Chronic migraine (20-25 headache days/month)
• Partial response to erenumab (reduction to 17 headache days/month)
• New onset hypertension with BP readings of 160/93 mmHg and 158/89 mmHg
• Previously well-controlled hypertension on lisinopril 40 mg daily
• Failed previous trials of topiramate and metoprolol

Rationale for Changing to Atogepant

Erenumab and Hypertension Risk

• Erenumab has been associated with development or worsening of hypertension in postmarketing studies, leading to revision of prescribing information to include this warning 1
• While clinical trials initially did not show increased hypertension risk, postmarketing data has identified hypertension as an adverse effect 2
• The temporal relationship between erenumab initiation and blood pressure elevation in this previously well-controlled hypertensive patient strongly suggests medication-induced hypertension

Benefits of Atogepant

• Atogepant is an effective alternative CGRP pathway antagonist (gepant) for migraine prevention
• Clinical trials demonstrate statistically significant reductions in monthly migraine days, headache days, and use of abortive medications 1
• Unlike erenumab, atogepant has not been associated with hypertension as a significant adverse effect
• The VA/DoD guidelines suggest atogepant as an effective option for migraine prevention 1

Alternative Options Considered

Increasing Erenumab to 140 mg monthly

• While higher doses may provide additional migraine relief 3, this would likely worsen the hypertension
• Increasing the dose of a medication causing an adverse effect is not recommended when safer alternatives exist

Changing to Rimegepant 75 mg every other day

• Rimegepant has shown less robust evidence for migraine prevention compared to atogepant
• The VA/DoD guidelines note that rimegepant's reduction in monthly migraine days (0.8) was not considered clinically significant 1

Continuing Erenumab with Hypertension Referral

• Not addressing the likely cause of hypertension (erenumab) while adding more antihypertensive medications represents poor clinical practice
• The International Society of Hypertension guidelines recommend identifying and eliminating substance/drug-induced causes of hypertension before intensifying therapy 1

Implementation Plan

1. Discontinue erenumab immediately
2. Start atogepant 60 mg daily
3. Continue lisinopril 40 mg daily for hypertension
4. Monitor blood pressure weekly for the first month after medication change
5. Reassess migraine frequency and blood pressure at 4-6 weeks

Monitoring and Follow-up

• Blood pressure should normalize within 2-4 weeks after discontinuing erenumab
• If hypertension persists after 4 weeks off erenumab, consider:
  • Confirming proper blood pressure measurement technique
  • Evaluating for other secondary causes of hypertension
  • Optimizing antihypertensive therapy per hypertension guidelines 1, 4
• Evaluate migraine response to atogepant at 8-12 weeks
• Document headache frequency in a headache diary

Important Considerations

• When managing patients with both migraine and hypertension, medication selection should prioritize agents that don't exacerbate either condition
• Beta-blockers (other than metoprolol, which failed in this patient) could be considered for both conditions if atogepant is ineffective 1
• For patients with resistant hypertension, consider adding a low-dose spironolactone as a 4th line agent if serum potassium is <4.5 mmol/L and eGFR >45 ml/min/1.73m² 1