I saw that there is a new medication for migraines Aimovig. How is it different from drugs like Imitrex and Relpax?
While both Aimovig and 'Triptan' medications are used for migraines, they are very different drugs and have different indications. Aimovig is indicated for the prevention of migraine headaches while Triptans are indicated for the treatment of migraine headaches.
In fact, in the clinical trials for Aimovig, participants were to use acute migraine treatments, such as the Triptan medication Imitrex, if needed and there weren't any apparent drug interactions. You can think of Aimovig as maintenance treatment to lessen the frequency of migraines and Triptan medications as treatment for migraines symptoms when they occur.
Prescription Triptan Medications Include:
- Alsuma (sumatriptan)
- Amerge (naratriptan)
- Axert (almotriptan)
- Frova (frovatriptan)
- Imitrex (sumatriptan)
- Maxalt (rizatriptan)
- Onzetra (sumatriptan)
- Relpax (eletriptan)
- Sumavel (sumatriptan)
- Zomig (zolmitriptan)
How Aimovig And 'Triptans' Work
Aimovig (Erenumab-aooe) is a human monoclonal antibody that binds to and antagonizes the calcitonin gene-related peptide (CGRP) receptor.
Calcitonin gene-related peptide is thought to be a major factor in how and why migraines occur. Among its functions, CGRP is involved in:
- Dilation of cerebral blood vessels
- Release of inflammatory mediators
- Transmission of nociceptive (i.e. pain) to the nervous system
All of the above, especially blood vessel dilation, are thought to be the main causes of migraine pain. In addition, multiple studies have found that blood concentrations CGRP are elevated during migraine and cluster headaches attacks.
As mentioned, Aimovig antagonizes CGRP receptor antagonists, which:
- Reduces vasodilation
- Reduces neurogenic inflammation
- Reduces pain transmission
There are a variety of Triptan medications available, many of which come in multiple dosage forms (e.g. tablets, injections). They all have the same mechanism of action however. Triptans work by stimulating various serotonin receptors (e.g. 5-HT1D, 5-HT1B) which inhibit:
- Dural vasodilation and inflammation
- Neurotransmission of pain
Studies also show that triptan medications decrease blood concentrations of CGRP after dosing.
How Aimovig And Triptans Are Dosed
- Aimovig is dosed as a once monthly subcutaneous injection. It is designed for self-administration meaning that you do not need to see your doctor for the injection.
- The recommended dosage of Aimovig is 70 mg once monthly but this can be increased to 140 mg once monthly, which is administered as two consecutive injections of 70 mg each.
- Triptans are available in multiple dosage forms, but the most commonly used remains by mouth dosage forms such as tablets.
- As Triptans are indicated for acute treatment of migraines, the usual dose is one tablet (or injection depending on the dosage form) as soon as possible after the onset of symptoms. Data shows the sooner a dose if taken after the first sign of migraine, the more effective they are.
- Triptans may be re-dosed if pain relief is not seen after 2 hours, and can be continued to be used at intervals of every 2 hours as needed up to the maximum daily dose of the drug (200 mg for Imitrex for example).
How Effective Are Aimovig And Triptans?
The prescribing information for Aimovig details 3 clinical trials, 2 of which were for individuals who experience episodic migraines (defined as 0-14 per months) while 1 involved individuals with chronic migraines (over 15 per month).
For Episodic Migraines:
- Aimovig reduced the average number of migraine days by 3 to 4
- 40-50% of individuals reduced their monthly migraine frequency by at least 50%
- Aimovig reduced the average number of migraine days by 6 to 7
- 40% of individuals reduced their monthly migraine frequency by at least 50%
Be sure to see the prescribing information for complete details on the clinical trial results.
Clinical studies for Triptan medications are available in their respective prescribing information. They all show that they are superior to placebo in treating the symptoms of acute migraine attacks but again, they does not play a role in preventing them.
For Imitrex for example, at a dose of 25mg, over 50% of individuals will achieve response to their symptoms. The response rate increases with dose, up to 100mg. As mentioned in the dosing profile for Triptans, they can be re-dosed every 2 hours (up to the maximum daily dose of the drug) until symptoms are resolved or managed.
Aimovig And Triptan Side Effects
The prescribing information for Aimovig lists the possible side effects of:
- Injection site reaction (e.g. injection site pain, injection site redness, and injection site itching)
- Muscle spasms
As Aimovig was just recently approved by the FDA in May of 2018, there is a lack of data regarding side effects. As the drug becomes commercially available, there is sure to be a more comprehensive list of side effects. From the outset at least, Aimovig appears to be fairly well tolerated.
The most common side effects of Triptans are:
- Burning/prickling sensation in extremities
- Warm/cold sensation
- Chest pain/tightness
- Neck/throat/jaw pain/tightness/pressure
Triptans are also associated with a range of less common, but more serious side effects such as:
- Increase in blood pressure
- Serotonin syndrome (when combined with other medication)
- Increased cardiovascular risk
- The biggest difference between Aimovig and Triptan medications is simply what they are used for.
- Aimovig is a maintenance therapy for the prevention (i.e. prophylaxis) of migraine headaches while Triptans are for the acute treatment of migraine headaches.
- Other differences in administration and side effect profiles exist as well.