5.1 Myocardial Ischemia, Myocardial Infarction,  and Prinzmetal’s Angina

FROVA is contraindicated in patients with ischemic or vasospastic CAD. There have been rare reports of serious cardiac adverse reactions, including acute myocardial infarction, occurring within a few hours following administration of FROVA. Some of these reactions occurred in patients without known CAD. FROVA may cause coronary artery vasospasm (Prinzmetal’s angina), even in patients without a history of CAD.

Perform a cardiovascular evaluation in triptan-naïve patients who have multiple cardiovascular risk factors (e.g., increased age, diabetes, hypertension, smoking, obesity, strong family history of CAD) prior to receiving FROVA.  Do not administer FROVA if there is evidence of CAD or coronary artery vasospasm [see Contraindications (4)]. For patients with multiple cardiovascular risk factors who have a negative cardiovascular evaluation, consider administrating the first FROVA dose in a medically-supervised setting and performing an electrocardiogram (ECG) immediately following FROVA administration.  For such patients, consider periodic cardiovascular evaluation in intermittent long-term users of FROVA.

5.2 Arrhythmias

Life-threatening disturbances of cardiac rhythm including ventricular tachycardia and ventricular fibrillation leading to death have been reported within a few hours following the administration of 5-HT1 agonists.  Discontinue FROVA if these disturbances occur.  FROVA is contraindicated in patients with Wolff-Parkinson-White syndrome or arrhythmias associated with other cardiac accessory conduction pathway disorders [see Contraindications (4)].

5.3 Chest, Throat, Neck, and Jaw Pain/Tightness/Pressure

Sensations of pain, tightness, pressure, and heaviness have been reported in the chest, throat, neck, and jaw after treatment with FROVA and are usually non-cardiac in origin.  However, perform a cardiac evaluation if these patients are at high cardiac risk.  The use of FROVA is contraindicated in patients with CAD and those with Prinzmetal’s angina [see Contraindications (4)].

5.4 Cerebrovascular Events

Cerebral hemorrhage, subarachnoid hemorrhage, stroke and other cerebrovascular events have been reported in patients treated with 5-HT1 agonists, and some have resulted in fatalities. In a number of cases, it appears possible that the cerebrovascular events were primary, the agonist having been administered in the incorrect belief that the symptoms experienced were a consequence of migraine, when they were not.

Before treating headaches in patients not previously diagnosed as migraineurs, and in migraineurs who present with symptoms atypical of migraine, other potentially serious neurological conditions need to be excluded. FROVA is contraindicated in patients with a history of stroke or TIA [see Contraindications (4)].

5.5 Other Vasospasm Reactions

FROVA, may cause non-coronary vasospastic reactions, such as peripheral vascular ischemia, gastrointestinal vascular ischemia and infarction (presenting with abdominal pain and bloody diarrhea), splenic infarction, and Raynaud’s syndrome. In patients who experience symptoms or signs suggestive of a vasospastic reaction following the use of any 5-HT1 agonist, rule out a vasospastic reaction before using FROVA [see Contraindications (4)].

Reports of transient and permanent blindness and significant partial vision loss have been reported with the use of 5-HT1 agonists. Since visual disorders may be part of a migraine attack, a causal relationship between these events and the use of 5-HT1 agonists have not been clearly established.

5.6  Medication Overuse Headache

Overuse of acute migraine drugs (e.g., ergotamine, triptans, opioids, or combination of these drugs for 10 or more days per month) may lead to exacerbation of headache (medication overuse headache). Medication overuse headache may present as migraine-like daily headaches or as a marked increase in frequency of migraine attacks. Detoxification of patients, including withdrawal of the overused drugs, and treatment of withdrawal symptoms (which often includes a transient worsening of headache) may be necessary.

5.7 Serotonin Syndrome

Serotonin syndrome may occur with FROVA, particularly during co-administration with selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), and monoamine oxidase (MAO) inhibitors [see Drug Interactions (7.3)]. Serotonin syndrome symptoms may include mental status changes (e.g., agitation, hallucinations, coma), autonomic instability (e.g., tachycardia, labile blood pressure, hyperthermia), neuromuscular aberrations (e.g., hyperreflexia, incoordination), and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). The onset of symptoms usually occurs within minutes to hours of receiving a new or a greater dose of a serotonergic medication. Discontinue FROVA if serotonin syndrome is suspected.

5.8 Increase in Blood Pressure

Significant elevation in blood pressure, including hypertensive crisis with acute impairment of organ systems, has been reported on rare occasions in patients treated with 5-HT1 agonists, including patients without a history of hypertension.  Monitor blood pressure in patients treated with FROVA.  FROVA is contraindicated in patients with uncontrolled hypertension [see Contraindications (4)].

5.9 Anaphylactic/Anaphylactoid Reactions

There have been reports of anaphylaxis, anaphylactoid, and hypersensitivity reactions including angioedema in patients receiving FROVA. Such reactions can be life threatening or fatal.  In general, anaphylactic reactions to drugs are more likely to occur in individuals with a history of sensitivity to multiple allergens.  FROVA is contraindicated in patients with a history of hypersensitivity reaction to FROVA [see Contraindications (4)].

6.1 Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

FROVA was evaluated in four randomized, double-blind, placebo-controlled, short-term trials. These trials involved 2392 patients (1554 on FROVA 2.5 mg and 838 on placebo). In these short-term trials, patients were predominately female (88%) and Caucasian (94%) with a mean age of 42 years (range 18 - 69).The treatment-emergent adverse events that occurred most frequently following administration of FROVA 2.5 mg (i.e., in at least 2% of patients), and at an incidence ≥1% greater than with placebo, were dizziness, paresthesia, headache, dry mouth, fatigue, flushing, hot or cold sensation, dyspepsia, skeletal pain, and chest pain. In a long term, open-label study where 496 patients were allowed to treat multiple migraine attacks with FROVA 2.5 mg for up to 1 year, 5% of patients (n=26) discontinued due to treatment-emergent adverse events.

Table 1 lists treatment-emergent adverse events reported within 48 hours of drug administration that occurred with FROVA 2.5 mg at an incidence of ≥2% and more often than on placebo, in the four placebo-controlled trials. The events cited reflect experience gained under closely monitored conditions of clinical trials in a highly selected patient population. In actual clinical practice or in other clinical trials, these incidence estimates may not apply, as the conditions of use, reporting behavior, and the kinds of patients treated may differ.

Table 1

The incidence of adverse events in clinical trials did not increase when up to 3 doses were used within 24 hours. The incidence of adverse events in placebo-controlled clinical trials was not affected by gender, age or concomitant medications commonly used by migraine patients. There were insufficient data to assess the impact of race on the incidence of adverse events.

Other Events Observed in Association with the Administration of FROVA

The incidence of frequently reported adverse events in four placebo-controlled trials are presented below. Events are further classified within body system categories. Frequent adverse events are those occurring in at least 1/100 patients.

Central and peripheral nervous system: dysesthesia and hypoesthesia.

Gastrointestinal: vomiting, abdominal pain and diarrhea.

Body as a whole: pain.

Psychiatric: insomnia and anxiety.

Respiratory: sinusitis and rhinitis.

Vision disorders: vision abnormal.

Skin and appendages: sweating increased.

Hearing and vestibular disorders: tinnitus.

Heart rate and rhythm: palpitation.

6.2 Postmarketing Experience

The following adverse reactions were identified during post approval use of FROVA. Because these events are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Central and peripheral nervous system:  Seizure.

7.1 Ergot-containing Drugs

Ergot-containing drugs have been reported to cause prolonged vasospastic reactions. Because these effects may be additive, use of ergotamine-containing or ergot-type medications (like dihydroergotamine or methysergide) and FROVA within 24 hours of each other is contraindicated [see Contraindications (4)].

7.2 5-HT1B/1D Agonists

Because their vasospastic effects may be additive, co-administration of FROVA and other 5-HT1 agonists (e.g., triptans) within 24 hours of each other is contraindicated [see Contraindications (4)].

7.3 Selective Serotonin Reuptake Inhibitors / Serotonin Norepinephrine Reuptake Inhibitors and Serotonin Syndrome

Cases of serotonin syndrome have been reported during combined use of triptans and SSRIs, SNRIs, TCAs, and MAO inhibitors [see Warnings and Precautions (5.7)].

8.1 Pregnancy

Pregnancy Category C: There are no adequate and well-controlled trials in pregnant women; therefore, frovatriptan should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

When pregnant rats were administered frovatriptan during the period of organogenesis at oral doses of 100, 500 and 1000 mg/kg/day (equivalent to 130, 650 and 1300 times the maximum recommended human dose [MRHD] of 7.5 mg/day on a mg/m2 basis) there were dose related increases in incidences of fetuses with dilated ureters, unilateral and bilateral pelvic cavitation, hydronephrosis, and hydroureters. A no-effect dose for renal effects was not established. This signifies a syndrome of related effects on a specific organ in the developing embryo in all treated groups, which is consistent with a slight delay in fetal maturation. This delay was also indicated by a treatment related increased incidence of incomplete ossification of the sternebrae, skull and nasal bones in all treated groups. Reduced fetal weights and an increased incidence of embryolethality were observed in treated rats; an increase in embryolethality occurred in both the embryo-fetal developmental study and in the prenatal-postnatal developmental study. No increase in embryolethality was observed at the lowest dose level studied (100 mg/kg/day, equivalent to 130 times the MRHD on a mg/m2 basis). When pregnant rabbits were dosed throughout organogenesis at oral doses up to 80 mg/kg/day (equivalent to 210 times the MRHD on a mg/m2 basis), no effects on fetal development were observed.

8.3 Nursing mothers

It is not known whether frovatriptan is excreted in human milk. Because many drugs are excreted in human milk, and because of the potential for serious adverse reactions in nursing infants from FROVA, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

In rats, oral dosing with frovatriptan resulted in levels of frovatriptan and/or its metabolites in milk up to four times higher than in plasma.

8.4 Pediatric use

The safety and effectiveness in pediatric patients have not been established. Therefore, FROVA is not recommended for use in patients under 18 years of age. There are no additional adverse reactions identified in pediatric patients based on postmarketing experience that were not previously identified in adults.

8.5 Geriatric use

Mean blood concentrations of frovatriptan in elderly patients were 1.5- to 2-times higher than those seen in younger adults [see Clinical Pharmacology (12.3)].   No dosage adjustment is necessary.

8.6 Patients with Hepatic Impairment

 No dosage adjustment is necessary when FROVA is given to patients with mild to moderate hepatic impairment.

There is no clinical or pharmacokinetic experience with FROVA in patients with severe hepatic impairment. Because a greater than two-fold increase in AUC is predicted in patients with severe hepatic impairment, there is a greater potential for adverse events in these patients, and FROVA should therefore be used with caution in that population.

12.1 Mechanism of Action

Frovatriptan binds with high affinity to 5-HT1B/1D receptors. The therapeutic activity of FROVA is thought to be due to the agonist effects at the 5-HT1B/1D receptors on intracranial blood vessels (including the arterio-venous anastomoses) and sensory nerves of the trigeminal system which result in cranial vessel constriction and inhibition of pro-inflammatory neuropeptide release.

12.3 Pharmacokinetics

The pharmacokinetics of frovatriptan are similar in migraine patients and healthy subjects.

Absorption

Mean maximum blood concentrations (Cmax) in patients are achieved approximately 2 - 4 hours after administration of a single oral dose of frovatriptan 2.5 mg. The absolute bioavailability of an oral dose of frovatriptan 2.5 mg in healthy subjects is about 20% in males and 30% in females. Food has no significant effect on the bioavailability of frovatriptan, but delays tmax by one hour.

Distribution

Binding of frovatriptan to serum proteins is low (approximately 15%). Reversible binding to blood cells at equilibrium is approximately 60%, resulting in a blood: plasma ratio of about 2:1 in both males and females. The mean steady state volume of distribution of frovatriptan following intravenous administration of 0.8 mg is 4.2 L/kg in males and 3.0 L/kg in females.

Metabolism

In vitro, cytochrome P450 1A2 appears to be the principal enzyme involved in the metabolism of frovatriptan. Following administration of a single oral dose of radiolabeled frovatriptan 2.5 mg to healthy male and female subjects, 32% of the dose was recovered in urine and 62% in feces. Radiolabeled compounds excreted in urine were unchanged frovatriptan, hydroxylated frovatriptan, N-acetyl desmethyl frovatriptan, hydroxylated N-acetyl desmethyl frovatriptan and desmethyl frovatriptan, together with several other minor metabolites. Desmethyl frovatriptan has lower affinity for 5-HT1B/1D receptors compared to the parent compound. The N-acetyl desmethyl metabolite has no significant affinity for 5-HT receptors. The activity of the other metabolites is unknown.

Elimination

After an intravenous dose, mean clearance of frovatriptan was 220 and 130 mL/min in males and females, respectively. Renal clearance accounted for about 40% (82 mL/min) and 45% (60 mL/min) of total clearance in males and females, respectively. The mean terminal elimination half-life of frovatriptan in both males and females is approximately 26 hours.

Special Populations

Hepatic Impairment

The AUC of frovatriptan in patients with mild (Child-Pugh 5-6) to moderate (Child-Pugh 7-9) hepatic impairment was about twice that of young, healthy subjects, but within the range observed in healthy elderly subjects and was considerably lower than the values attained with higher doses of frovatriptan (up to 40 mg), which were not associated with any serious adverse effects. There is no clinical or pharmacokinetic experience with FROVA in patients with severe hepatic impairment.

Renal Impairment

The pharmacokinetics of frovatriptan following a single oral dose of 2.5 mg was not different in patients with renal impairment (5 males and 6 females, creatinine clearance 16 - 73 mL/min) compared to subjects with normal renal function.

Age

Mean AUC of frovatriptan was 1.5- to 2-fold higher in healthy elderly subjects (age 65 – 77 years) compared to those in healthy younger subjects (age 21 - 37 years). There was no difference in tmax or t1/2 between the two populations.

Sex

There was no difference in the mean terminal elimination half-life of frovatriptan in males and females. Bioavailability was higher, and systemic exposure to frovatriptan was approximately 2-fold greater, in females than males, irrespective of age.

Race

The effect of race on the pharmacokinetics of frovatriptan has not been examined.

Drug Interaction Studies

Frovatriptan is not an inhibitor of human monoamine oxidase (MAO) enzymes or cytochrome P450 (isozymes 1A2, 2C9, 2C19, 2D6, 2E1, 3A4) in vitro at concentrations up to 250 to 500- fold higher than the highest blood concentrations observed in man at a dose of 2.5 mg. No induction of drug metabolizing enzymes was observed following multiple dosing of frovatriptan to rats or on addition to human hepatocytes in vitro. Although no clinical trials have been performed, it is unlikely that frovatriptan will affect the metabolism of co-administered drugs metabolized by these mechanisms.

Oral Contraceptives

Retrospective analysis of pharmacokinetic data from females across trials indicated that the mean Cmax and AUC of frovatriptan are 30% higher in those subjects taking oral contraceptives compared to those not taking oral contraceptives. 

Ergotamine

The AUC and Cmax of frovatriptan (2 x 2.5 mg dose) were reduced by approximately 25% when co-administered with ergotamine tartrate [see Contraindications (4), Drug Interactions (7.1)].

Propranolol

Propranolol increased the AUC of frovatriptan 2.5 mg in males by 60% and in females by 29%. The Cmax of frovatriptan was increased 23% in males and 16% in females in the presence of propranolol. The tmax as well as half-life of frovatriptan, though slightly longer in the females, were not affected by concomitant administration of propranolol.

Moclobemide

The pharmacokinetic profile of frovatriptan was unaffected when a single oral dose of frovatriptan 2.5 mg was administered to healthy female subjects receiving the MAO-A inhibitor, moclobemide, at an oral dose of 150 mg bid for 8 days.

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenesis

The carcinogenic potential of orally administered frovatriptan was evaluated in an 84-week study in mice (4, 13, and 40 mg/kg/day), a 104-week study in rats (8.5, 27 and 85 mg/kg/day), and a 26-week study in p53(+/-) transgenic mice (20, 62.5, 200, and 400 mg/kg/day). Although a maximum tolerated dose was not achieved in the 84-week mouse study and in female rats, plasma exposures at the highest doses studied were higher than that achieved in humans at the maximum recommended human dose (MRHD) of 7.5 mg/day. There were no increases in tumor incidence in the 84-week mouse study at doses producing plasma exposures (AUC) 140 times that in humans at the MRHD. In the rat study, there was a statistically significant increase in the incidence of pituitary adenomas in males only at 85 mg/kg/day, a dose associated with a plasma AUC 250 times that in humans at the MRHD. In the 26-week p53(+/-) transgenic mouse study, the incidence of subcutaneous sarcomas was increased in females at doses of 200 and 400 mg/kg/day.

These sarcomas were associated with subcutaneously implanted animal identification transponders, and are not considered to be relevant to humans. There were no other increases in tumor incidence of any type in any dose group.

Mutagenesis

Frovatriptan was clastogenic in human lymphocyte cultures, in the absence of metabolic activation. In the bacterial reverse mutation assay (Ames test), frovatriptan produced an equivocal response in the absence of metabolic activation. Frovatriptan was negative in an in vitro mouse lymphoma tk assay and an in vivo mouse bone marrow micronucleus test.

Impairment of Fertility

Male and female rats were dosed orally with frovatriptan prior to and during mating and in females up to implantation, at doses of 100, 500, and 1000 mg/kg/day (equivalent to approximately 130, 650, and 1300 times the MRHD on a mg/m2 basis). At all dose levels, there was an increase in the number of females that mated on the first day of pairing compared to control animals. This occurred in conjunction with a prolongation of the estrous cycle. In addition, females had a decreased mean number of corpora lutea, and consequently a lower number of live fetuses per litter, which suggested a partial impairment of ovulation. There were no other fertility-related effects.