Safety trial with the 5HT1B/1D agonist avitriptan (BMS-180048) in patients with migraine who have experienced pressure, tightness, and/or pain in the chest, neck, and/or throat following sumatriptan

Evaluating the safety and tolerability profile of acute treatments for migraine

Among the medications that have been used as acute treatments for migraine are nonspecific agents, including nonsteroidal anti-inflammatory drugs (NSAIDs), analgesics (either single or combination), and narcotics, as well as migraine-specific medications, including ergot alkaloids and triptans (5-hydroxytryptamine 1B/1D agonists). All of these drugs have side effects that vary in type and severity. Side effects of nonspecific medications, including gastrointestinal (GI) and renal effects with NSAIDs and cognitive effects and the potential for abuse with narcotics and butalbital-containing medications, have been documented over time, as these medications have been used for various indications. Side effects of the migraine-specific medications include GI and vascular symptoms with the ergots; for the triptans, they include chest and neurologic symptoms. Although adverse events are reported fairly frequently in patients receiving triptans, they are usually mild, and few patients discontinue therapy because of them. The most serious adverse events are cardiovascular. Because of potential vasoconstrictor effects--mild and transient increases in blood pressure and mild and transient effects on coronary artery tone--triptans as a class are contraindicated in patients with established or clinically suspected cardiovascular disease, specifically ischemic heart disease and uncontrolled hypertension. Other adverse events, including the potential for drug-drug interactions, are less common. Therefore, consideration should be given to the tolerability and safety of medications before their use as abortive medications for the treatment of migraine headache.

When to Stress Over Triptans: A Markov Analysis of Cardiovascular Risk in Migraine Treatment

BACKGROUND

Migraines affect 10% of the U.S. population and the episodes are frequently associated with significant disability. Triptans, 5HT1 receptor agonists, can be highly effective in treating pain and reducing disability. However, reports of cardiac events associated with triptan ingestion have led to concerns about its use in the face of possible cardiac disease.

OBJECTIVE

Should a patient without known cardiovascular disease (CAD) and moderately severe to severe migraines undergo cardiovascular testing prior to the initiation of triptan therapy?

DESIGN

A Markov model of migraine and cardiac disease using DATA 4.0. Three strategies were compared: (1) use triptans without further evaluation (TREAT); (2) test, then treat if negative (TEST); and (3) avoid triptans (NOTRIPTAN). Triptans were prohibited if a cardiac event occurred.

DATA

Model inputs were derived from the literature and subjected to sensitivity analyses across all possible values.

TIME HORIZON

Markov cycle is 1 week.

OUTCOMES

The primary outcomes of interest were quality-adjusted life expectancy, in years (QALYs) and the impact of various cardiovascular risk levels on the preferred strategy.

RESULTS

For the base case results were TREAT 19.4 QALYs, TEST 19.2, NOTRIPTAN 19.1. When altering CAD probability: TREAT dominated from 0 to 87%, TEST 87% to 97%, and NOTRIPTAN above 97%. Results were robust during sensitivity analyses.

CONCLUSIONS

This analysis suggests that even for individuals with a relatively high risk of CAD it is not beneficial to perform cardiac testing, nor to avoid triptans. The exact level of cardiac risk at which testing should be considered is probably at or above 87%.

Frequent Triptan Use: Observations on Safety Issues

OBJECTIVE

To examine the safety of frequent triptan use over extended periods. For a small group of patients with refractory migraine plus chronic daily headache, triptans are effective.

METHODS

This retrospective study primarily evaluated the cardiac safety of daily triptan use in 118 patients and, in addition, hematologic tests were assessed. Each patient had utilized a triptan for a minimum of 4 days per week for at least 6 months. Patients with rebound headache had been withdrawn from the triptans. Most patients (97 of 118) averaged 1 tablet daily; most would occasionally go for several days without a triptan. Forty patients had taken a triptan for 6 months to 2 years, 37 patients from 2 to 4 years, and 41 for 4 or more years.

RESULTS

Routine hematologic tests were performed periodically on all patients, and no abnormalities were attributable to triptans. Almost all patients had an electrocardiogram, and no abnormal electrocardiograms were felt to be related to triptans. Cardiac echocardiography was performed in 57 patients. The 10 abnormal echocardiograms were not due to triptans. All 20 cardiac stress tests revealed normal findings. Adverse events were minimal; 9 patients described fatigue due to triptans, and 5 had mild chest tightness.

CONCLUSION

This long-term study of 118 patients indicates that frequent triptan use may be relatively safe.

Tolerability of the triptans: clinical implications

The triptans represent a relatively new class of compounds effective in the treatment of migraine. The safety and tolerability of these drugs have been extensively investigated since the first triptan (sumatriptan) became commercially available. A report on a very large population of patients tested during clinical trials and in postmarketing studies, confirms that these drugs are safe and well tolerated when correctly used. Adverse events are frequently reported, but are usually mild and only a few patients discontinue therapy because of them. These adverse events include, in particular, the so-called 'triptan symptoms' (tingling, sensation of warmth, etc.). The exact mechanism of chest symptoms reported by 20% of patients with migraine treated with triptans remains unclear, but are exceptionally related to a cardiac mechanism. CNS adverse events (i.e. somnolence) are also reported, but it is a matter of debate whether they are related to the pharmacological properties (i.e. lipophilicity) of the drug or are symptoms of the disease itself. The potential risk for drug overuse must be taken into account when the triptans are given to patients with a high frequency of migraine attacks. Clinical interaction of triptans with other drugs metabolised in the liver may theoretically influence the incidence of adverse events, but there is little evidence to support this assumption. There is no evidence of a teratogenic risk of triptans in pregnant women taking these drugs.

Integrating the triptans into clinical practice

The triptans (selective serotonin agonists) are becoming the first-line alternatives in the acute pharmacological treatment of migraine, at least for attacks of moderate-to-severe intensity. Although clinical trials demonstrate significant differences in efficacy between triptan tablets, they often appear similar in efficacy when used in clinical practice, particularly after dose adjustments. Most patients with migraine consider drugs that can be administered orally to be the most user-friendly. However, gastrointestinal absorption may be impaired during migraine attacks because gastric motility is inhibited, and there is a risk that nausea during the attack will culminate in vomiting. Furthermore, in addition to their antimigraine properties, triptans may prolong the gastric emptying time. For this reason the absorption of any triptan taken orally during the migraine attack will be erratic and treatment effects inconsistent. Despite these barriers to good efficacy and high reliability, the tablet is the most commonly used triptan formulation.

How does almotriptan compare with other triptans? A review of data from placebo-controlled clinical trials

Almotriptan, the new selective 5-HT1B/1D agonist, has a higher oral bioavailability than any other triptan, with more than two thirds of the administered dose absorbed within the first hour both inside and outside of a migraine attack. Gender or the presence of food in the stomach does not affect its pharmacokinetic profile, and the compound has no clinically relevant interactions with other drugs. Among the available triptans, response rates at 2 hours range from 50% to 80%, with 20% to 50% of patients pain-free. Almotriptan 12.5 mg provides similar efficacy, with significant advantage over placebo at 30 minutes and a reliable consistency (75% in two of three attacks). Headache typically recurs in 25% to 45% of patients with most triptans. The recurrence rate with almotriptan 12.5 mg, 18% to 27%, is among the lowest reported. The tolerability of almotriptan 12.5 mg is close to that of placebo with a low incidence of central nervous system side effects and chest symptoms. In conclusion, almotriptan's consistent pharmacokinetics and good efficacy, in combination with excellent tolerability, make it an attractive choice in the acute treatment of migraine attacks.

The safety of triptans in the treatment of patients with migraine

The introduction of the triptans (5-hydroxytryptophan [5-HT] (1B/1D) agonists) in the past decade has brought migraine-specific pain relief to those suffering from migraine. These drugs activate the serotonin receptors 5-HT(1B) and 5-HT(1D) on cerebral vessels. Concerns about their safety, particularly in patients with vascular risk factors, have been raised because triptans also activate the 5-HT(1B) receptors on coronary arteries. Although triptans are contraindicated in patients with cardiac or cerebrovascular disease, they are safer than many other medications used to treat patients with migraine, including the nonspecific serotonin-agonist ergot preparations.

Safety and efficacy of PNU-142633, a selective 5-HT1D agonist, in patients with acute migraine

In this randomized, double-blind, placebo-controlled, parallel-group study, patients received a single 50-mg oral dose of a 5-HT(1D) agonist, PNU-142633 (n = 34), or matching placebo (n = 35) during an acute migraine attack. No statistically significant treatment effects were observed at 1 and 2 h after dosing, even after stratifying by baseline headache intensity. At 1 and 2 h post-dose, 8.8% and 29.4% of the PNU-142633 group, respectively, and 8.6% and 40.0% of the placebo group, respectively, experienced headache relief; 2.9% and 8.8% of the PNU-142633 group and 0% and 5.7% of the placebo group were free of headache pain. Adverse events associated with PNU-142633 treatment included chest pain (two patients) and QTc prolongation (three patients). Results from this study suggest that anti-migraine efficacy is not mediated solely through the 5-HT(1D) receptor subtype, although this receptor may contribute, at least in part, to the adverse cardiovascular effects observed with 5-HT agonist medications.

Hemodynamic and electrocardiographic effects of almotriptan in healthy volunteers

We studied the possible cardiovascular effects of single oral doses of 12.5, 25, and 50 mg of almotriptan, a new triptan for treatment of migraine, in a randomized, double-blind, four-way crossover, placebo-controlled study in 24 healthy volunteers aged 18 to 35 years. Doses were given at 1-week intervals. Cardiovascular effects were assessed by frequent recording of blood pressure and heart rate, 12-lead electrocardiogram (ECG) (recorded at 25 mm/s paper speed and 1 cm/mV and at 50 mm/s and 2 cm/mV), and continuous ECG monitoring for 12 h after each dose. ECG variables, PR, QRS, QT interval, and QT dispersion, were measured. QT intervals were adjusted for heart rate using Bazett's formula. None of the doses of almotriptan differed significantly from placebo with respect to PR, QRS, or QTc intervals, QTc dispersion, heart rate, or continuous ECG monitoring. Almotriptan 12.5 mg did not differ significantly from placebo with respect to systolic or diastolic blood pressure, but almotriptan 25 and 50 mg raised systolic blood pressure by a mean of 2.78 and 4.17 mm Hg, and diastolic blood pressure by 3.77 and 6.11 mm Hg, respectively, during 0 to 4 h after dosing. Thus none of the doses of almotriptan affected the ECG, and the 12.5-mg dose (the expected therapeutic dose) had no hemodynamic effects. Almotriptan in doses of 25 and 50 mg caused a small, dose-related increase in systolic and diastolic blood pressure, as seen with other triptans.