Erenumab (Aimovig) Injection: Uses, Dose, MOA, Brands, Side Effects

Erenumab (Aimovig) injection is an FDA-approved medication for the prevention of migraine headaches. It got FDA approval in the US in 2018.

Erenumab belongs to the class of drugs that bind to and alter the interaction between the calcitonin gene-related peptide (CGRP) and its receptors (CGRPR).

Inhibiting the function of CGRPR results in an inhibitory vasodilatory effect on the intracranial blood vessels, the primary pathology that causes migraine headaches.

Other drugs in the same group that blocks the CGRPR and are used to prevent migraine headaches include:

The ‘gepants’ are oral drugs that also block the CGRPR, however, these drugs are used to abort an acute migraine episode. These drugs include:

Erenumab (Aimovig) Uses (Indications) [Ref]:

Aimovig is indicated for the preventive treatment of migraine headaches in individuals who have frequent and severe episodes of migraine headaches.

Preventive treatment is indicated in those individuals who have three or more migraine episodes per month, or less than three episodes but the severity of the headache is intense and does not easily subside with primary ER drugs.

In addition, individuals with a single episode of migraine headache per month that is associated with focal weakness (basilar migraine) or the duration exceeds 24 hours.

Aimovig should not be used to abort an acute episode of migraine headache. It takes about six days for the drug to reach the maximum plasma concentrations after it is administered to the skin. One can not wait for six days!!

Other drugs from the same class, also called the “gepants” can be used to treat acute migraine headaches. These include Nurtec ODT (Rimegepant) and Ubrelvy (Ubrogepant).

Read: Aimovig Vs Ajovy (Erenumab VS Fremanezumab)

Erenumab (Aimovig) Dosing:

Aimovig is administered in a dose of 70 mg once monthly which is considered the usual recommended dose.

However, for some patients who have persistent headaches despite the usually recommended dose, 140 mg may be administered once a month.

What to do if you miss your dose?

In case a dose is missed, administer it immediately. Schedule the next dose from the last dose administered.

For example, you were supposed to administer your dose on the 1st of each month but you forgot your dose. On the 10th of the month, you realize that you have missed your dose.

You should immediately administer your dose on the 10th of the month. Your next dose will be due on the 10th of the next month.

Can you use Erenumab (Aimovig) with concomitant CYP 450 enzyme inducers or inhibitors?

Yes. There is no need to reduce or increase the dose while you are on concomitant CYP450 enzyme inducers or inhibitors.

Can you use Aimovig with Sumatriptan, Zolmitriptan, or other migraine medications?

Yes. In clinical trials, the concomitant use of Sumatriptan and Aimovig did not alter the pharmacokinetics of each other.

In addition, there was no significant change in the blood pressure or any adverse cardiovascular events noted when triptans were given in combination with Aimovig.

Aimovig Drug Interactions:

Aimovig should not be administered with concomitant Belimumab. It may increase the adverse reactions associated with belimumab.

Read: New First-Line Treatments for Migraine Prevention

How to Administer Erenumab (Aimovig)?

Aimovig is available as a single-dose prefilled syringe and single-dose prefilled Sureclick autoinjector containing 70 mg/ml of Erenumab.

It is intended for subcutaneous use only. The patients should be educated about the injection technique so that they can self-administer the dose each month without visiting a healthcare facility.

The injection should be inspected before administering it. It should contain clear liquid without any particulate matter.

Before administering it, it should be kept at room temperature for about thirty minutes to lower its temperature.

The injection site for Aimovig includes:

The anterior aspect of the abdomen 3 – 5 cm away from the navel
The skin of the buttocks and anterior aspects of the thighs
Back of the upper arms (only in overweight and heavy people)

Erenumab (Aimovig) Use in Pregnancy and Breastfeeding:

Aimovig has been labeled as Pregnancy Risk Category B1. The US FDA has not issued any pregnancy risk category to the drug because it has not been studied in human pregnant females.

The manufacturer recommends avoiding it in pregnant females.

Similarly, the drug has not been studied in nursing or lactating mothers. It is therefore recommended to weigh the risks of drug exposure in the infant and the benefits of treating the mother.

Erenumab (Aimovig) Dose in Kidney and Liver Disease:

Aimovig has not been studied in patients with advanced liver or kidney disease. It should not be used in patients with Child Class C Liver disease.

Similarly, in patients with kidney disease, it should be avoided if the CrCl is less than 30 ml/minute.

In those with mild to moderate renal or hepatic dysfunction, no dose adjustment is recommended.

Read: Ubrelvy Vs Nurtec Reviews on Reddit by Real Migraine Patients

Erenumab (Aimovig) Side effects:

Erenumab (Aimovig), like other monoclonal antibodies that target the CGRPR, has a very good safety profile.

In clinical trials, the most commonly observed adverse reactions were related to injection-site reactions and constipation.

Other less commonly observed side effects of Aimovig that the patients experienced were muscle cramps and muscle spasms.

The percentage of the most common side effects are mentioned in the table below:

Side effects	Aimovig 70 mg monthly	Aimovig 140 mg monthly	Placebo
Injection-site-related side effects	6%	5%	3%
Constipation	1%	3%	1%
Muscle cramps and muscle spasms	<1%	2%	<1%

Injection site reactions that were commonly observed include redness, swelling, pain, and itching at the site.

Erenumab (Aimovig) Contraindications and Warnings:

No contraindications have been mentioned in the manufacturer’s labeling.

However, hypersensitivity reactions including immediate and delayed-type hypersensitivity reactions have been observed in patients who are allergic to the drug.

The immediate type of hypersensitivity reactions can occur within hours of administering the drug. The delayed type of hypersensitivity reaction can occur as late as one week after the last dose.

In case of any reactions are observed, the patient should be monitored and supportive treatment should be given.

Read: Anti inflammatory Diet for Migraines Prevention

Erenumab (Aimovig) Monitoring Parameters:

No specific drug monitoring parameters are recommended. The response to treatment should, however, be monitored.

For individuals who have an inadequate response to the treatment after three months, the drug may be switched to either another one from the same group or a second drug may be added to the treatment regimen.

Other drugs that may be used instead of Aimovig include Emgality (Galcanezumab) and Ajovy (Fremanezumab).

Erenumab (Aimovig) Mechanism of action (MOA):

Erenumab-aooe (Aimovig) is a human monoclonal antibody that blocks the binding of CGRP to its receptors. Subsequently, the process by which the CGRPR causes intracranial vasodilation is halted.

Thus, because of the indirect vasoconstrictive effects of Aimovig, it is used for the prevention and chronic management of migraine headaches.

Unlike Sumatriptan and other triptans, it is not associated with angina and hypertension.

Half-life elimination:

The effective half-life of the drug is 28 days.

Absorption:

After subcutaneous administration, the peak plasma concentration reaches in about six days.

Bioavailability:

After subcutaneous administration, it has a bioavailability of 82%.

Metabolism:

Aimovig exhibits elimination in two phases. When administered as a low-dose injection, the drug is cleared from the plasma by saturable binding to its receptors.
However, it is eliminated by non-saturable proteolytic degradation when administered in high doses.