Rx CARE

FDA approves another triptan for migraine in adults

Another triptan drug has been approved by the Food & Drug Administration. Ireland-based Elan Corp. received FDA approval for frovatriptan, which will be marketed under the brand name Frova. It is indicated in the acute treatment of migraine attacks with or without aura in adults. Elan is awaiting finalization of a comarketing agreement before launching the drug.

Like other products that fall under the triptan class of drugs, frovatriptan is an agonist at 5-HT₁ receptors, binding specifically at the 5HT_1B and 5HT_1D receptors, and it is more effective than placebo at relieving migraine and other symptoms. Like those of other triptans, frovatriptan's package insert carries a warning about the risk for potentially fatal cardiac events. Because of this, the triptans are contraindicated in patients with ischemic heart disease. Elan's frovatriptan also carries a contraindication for cerebrovascular and peripheral vascular disease.

While results from studies that compare the triptans with one another show that they vary little in potency at receptor sites, onset, side effects, frequency of use, etc., in the final analysis, it is the patient's response and satisfaction to one particular brand of triptan over another that increases a product's market share.

Pharmacokinetic factors among the triptans seem to be a key element as well. Onset of action is a bit slower with frovatriptan, especially when the drug is taken with food. However, frovatriptan has a much longer half-life. At 26 hours, it far exceeds that of the others (see table). Because of this, frovatriptan may alleviate migraine longer than other triptans, and the need to take a second dose (an option with all of the triptans) may occur less often. However, a longer half-life can also be a detriment when adverse reactions or drug interactions are troublesome.

While most triptans are metabolized by monoamine oxidase (MAO) and consequently interact with MAO inhibitors, both frovatriptan and naratriptan are exceptions. Another advantage to frovatriptan is that it is the only triptan that does not require dose adjustment in patients with hepatic or renal insufficiency. The others require at least cautious use in one or both of these disorders.

Considering all this, Chad Shedron, Pharm.D., thinks frovatriptan may be a good second- or third-line agent. "I don't see it being used as a first-line agent," he said. Shedron, who owns Family PharmaCare pharmacy in West Lafayette, Ind., probably won't stock the product initially unless he receives prescriptions for it. The drug's slower onset may be a consideration for some patients. "If you have that kind of pain, you want it gone," he said. However, he feels frovatriptan's long half-life might prove to be an advantage for patients who often experience migraine recurrence within 24 hours. And, patients who are able to recognize migraine onset early may not have a problem with slower time to peak drug levels.

"I think another choice is always an advantage," Shedron said, summing up his reaction to the approval of the new drug. Patients who have not been satisfied with other triptans may find that frovatriptan works for them. Like the selective serotonin reuptake inhibitors, the triptans comprise a class in which patients just have to find the right drug. In this case, it seems the more options available, the better.

Elan expects to have its new product ready for market this quarter.

Jillene Magill-Lewis, R.Ph.

Based in Washington State, the author writes frequently about health-related subjects.

TIPS TO REMEMBER: Frova

• Frova is contraindicated in patients with ischemic heart disease, cerebrovascular syndromes, peripheral vascular disease, or uncontrolled hypertension.

• Frova is not for use in patients with uncontrolled hypertension or who have basilar or hemiplegic migraine.

• Cardiovascular evaluation is strongly recommended for patients with any risk factors for vasospastic coronary artery disease (e.g., obesity, diabetes, hypertension, smoking, hypercholesterolemia, menopause, and so on).

• Frova should not be taken within 24 hours of any ergot-containing drug or another triptan (5-HT agonist).

• Drug interactions may also occur with the SSRIs, oral contraceptives, and propranolol.

• The most common side effects of Frova are dizziness, drowsiness, dry mouth, indigestion, chest pain, and odd sensations (tingling, hot flashes).

A pharmacokinetic comparison of the triptans

 

Jillene Lewis. FDA approves another triptan for migraine in adults. Drug Topics 2002;3:22.