Formoterol

12.1 Mechanism of Action Formoterol fumarate is a long-acting, beta 2 -adrenergic receptor agonist (beta 2 -agonist). Inhaled formoterol fumarate acts locally in the lung as a bronchodilator. In vitro studies have shown that formoterol has more than 200-fold greater agonist activity at beta 2 -receptors than at beta 1 -receptors. Although beta 2 -receptors are the predominant adrenergic receptors in bronchial smooth muscle and beta 1 -receptors are the predominant receptors in the heart, there are also beta 2 -receptors in the human heart comprising 10% to 50% of the total beta-adrenergic receptors. The precise function of these receptors has not been established, but they raise the possibility that even highly selective beta 2 -agonists may have cardiac effects. The pharmacologic effects of beta 2 -adrenoceptor agonist drugs, including formoterol, are at least in part attributable to stimulation of intracellular adenyl cyclase, the enzyme that catalyzes the conversion of adenosine triphosphate (ATP) to cyclic-3', 5'-adenosine monophosphate (cyclic AMP). Increased cyclic AMP levels cause relaxation of bronchial smooth muscle and inhibition of release of mediators of immediate hypersensitivity from cells, especially from mast cells. In vitro tests show that formoterol is an inhibitor of the release of mast cell mediators, such as histamine and leukotrienes, from the human lung. Formoterol also inhibits histamine-induced plasma albumin extravasation in anesthetized guinea pigs and inhibits allergen-induced eosinophil influx in dogs with airway hyper-responsiveness. The relevance of these in vitro and animal findings to humans with COPD is unknown.

1 INDICATIONS AND USAGE Formoterol fumarate inhalation solution is a long-acting beta 2 -adrenergic agonist (beta 2 -agonist) indicated for: Long-term, twice daily (morning and evening) administration in the maintenance treatment of bronchoconstriction in patients with chronic obstructive pulmonary disease (COPD), including chronic bronchitis and emphysema. ( 1.1 ) Important limitations of use: Formoterol fumarate inhalation solution is not indicated to treat acute deteriorations of chronic obstructive pulmonary disease. ( 1.2 , 5.2 ) Formoterol fumarate inhalation solution is not indicated to treat asthma. ( 1.2 ) 1.1 Maintenance Treatment of COPD Formoterol fumarate inhalation solution is indicated for the long-term, twice daily (morning and evening) administration in the maintenance treatment of bronchoconstriction in patients with chronic obstructive pulmonary disease (COPD), including chronic bronchitis and emphysema. 1.2 Important Limitations of Use Formoterol fumarate inhalation solution is not indicated to treat acute deteriorations of chronic obstructive pulmonary disease [see WARNINGS AND PRECAUTIONS ( 5.2 )]. Formoterol fumarate inhalation solution is not indicated to treat asthma. The safety and effectiveness of formoterol fumarate inhalation solution in asthma have not been established.

2 DOSAGE AND ADMINISTRATION The recommended dose of formoterol fumarate inhalation solution is one 20 mcg unit-dose vial administered twice daily (morning and evening) by nebulization. A total daily dose greater than 40 mcg is not recommended. Formoterol fumarate inhalation solution should be administered by the orally inhaled route via a standard jet nebulizer connected to an air compressor. The safety and efficacy of formoterol fumarate inhalation solution have been established in clinical trials when administered using the PARI-LC Plus ® nebulizer (with a facemask or mouthpiece) and the PRONEB ® Ultra compressor. The safety and efficacy of formoterol fumarate inhalation solution delivered from non-compressor based nebulizer systems have not been established. Formoterol fumarate inhalation solution should always be stored in the foil pouch, and only removed IMMEDIATELY BEFORE USE. Contents of any partially used container should be discarded. If the recommended maintenance treatment regimen fails to provide the usual response, medical advice should be sought immediately, as this is often a sign of destabilization of COPD. Under these circumstances, the therapeutic regimen should be re-evaluated and additional therapeutic options should be considered. The drug compatibility (physical and chemical), efficacy, and safety of formoterol fumarate inhalation solution when mixed with other drugs in a nebulizer have not been established. For oral inhalation only. One 20 mcg/2 mL vial every 12 hours. ( 2 ) For use with a standard jet nebulizer (with a facemask or mouthpiece) connected to an air compressor. ( 2 )

6 ADVERSE REACTIONS Long-acting beta 2 -adrenergic agonists, such as formoterol fumarate, as monotherapy (without an inhaled corticosteroid) for asthma increase the risk of asthma-related events. Formoterol fumarate is not indicated for the treatment of asthma [see WARNINGS AND PRECAUTIONS ( 5.1 )]. Most common adverse reactions ( > 2% and more common than placebo) are diarrhea, nausea, nasopharyngitis, dry mouth, vomiting, dizziness, and insomnia ( 6.2 ) To report SUSPECTED ADVERSE REACTIONS, contact Micro Labs USA Inc., at 1-855-839-8195 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Beta 2 -Agonist Adverse Reaction Profile Adverse reactions to formoterol fumarate inhalation solution are expected to be similar in nature to other beta 2 -adrenergic receptor agonists including: angina, hypertension or hypotension, tachycardia, arrhythmias, nervousness, headache, tremor, dry mouth, muscle cramps, palpitations, nausea, dizziness, fatigue, malaise, insomnia, hypokalemia, hyperglycemia, and metabolic acidosis. 6.2 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. Adults with COPD The data described below reflect exposure to formoterol fumarate inhalation solution 20 mcg twice daily by oral inhalation in 586 patients, including 232 exposed for 6 months and 155 exposed for at least 1 year. Formoterol fumarate inhalation solution was studied in a 12-week, placebo-and active-controlled trial (123 subjects treated with formoterol fumarate inhalation solution) and a 52-week, active-controlled trial (463 subjects treated with formoterol fumarate inhalation solution). Patients were mostly Caucasians (88%) between 40 to 90 years old (mean, 64 years old) and had COPD, with a mean FEV 1 of 1.33 L. Patients with significant concurrent cardiac and other medical diseases were excluded from the trials. Table 1 shows adverse reactions from the 12-week, double-blind, placebo-controlled trial where the frequency was greater than or equal to 2% in the formoterol fumarate inhalation solution group and where the rate in the formoterol fumarate inhalation solution group exceeded the rate in the placebo group. In this trial, the frequency of patients experiencing cardiovascular adverse events was 4.1% for formoterol fumarate inhalation solution and 4.4% for placebo. There were no frequently occurring specific cardiovascular adverse events for formoterol fumarate inhalation solution (frequency greater than or equal to 1% and greater than placebo). The rate of COPD exacerbations was 4.1% for formoterol fumarate inhalation solution and 7.9% for placebo. TABLE 1 Number of patients with adverse reactions in the 12-week multiple-dose controlled clinical trial Adverse Reaction Formoterol Fumarate Inhalation Solution 20 mcg Placebo n (%) n (%) Total Patients 123 (100) 114 (100) Diarrhea 6 (4.9) 4 (3.5) Nausea 6 (4.9) 3 (2.6) Nasopharyngitis 4 (3.3) 2 (1.8) Dry Mouth 4 (3.3) 2 (1.8) Vomiting 3 (2.4) 2 (1.8) Dizziness 3 (2.4) 1 (0.9) Insomnia 3 (2.4) 0 0 Patients treated with formoterol fumarate inhalation solution 20 mcg twice daily in the 52-week open-label trial did not experience an increase in specific clinically significant adverse events above the number expected based on the medical condition and age of the patients. 6.3 Postmarketing Experience The following adverse reactions have been reported during post-approval use of formoterol fumarate inhalation solution. Because these reactions 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. Anaphylactic reactions, urticaria, angioedema (presenting as face, lip, tongue, eye, pharyngeal, or mouth edema), rash, and bronchospasm

7 DRUG INTERACTIONS Other adrenergic drugs may potentiate effect. Use with caution. ( 5.3 , 7.1 ) Xanthine derivatives, steroids, diuretics, or non-potassium sparing diuretics may potentiate hypokalemia or ECG changes. Use with caution. ( 5.7 , 7.2 , 7.3 ) MAO inhibitors, tricyclic antidepressants and drugs that prolong QTc interval may potentiate effect on the cardiovascular system. Use with extreme caution. ( 7.4 ) Beta-blockers may decrease effectiveness. Use with caution and only when medically necessary. ( 7.5 ) 7.1 Adrenergic Drugs If additional adrenergic drugs are to be administered by any route, they should be used with caution because the sympathetic effects of formoterol may be potentiated [see WARNINGS AND PRECAUTIONS ( 5.3 , 5.5 , 5.6 , 5.7 )]. 7.2 Xanthine Derivatives, Steroids, or Diuretics Concomitant treatment with xanthine derivatives, steroids, or diuretics may potentiate any hypokalemic effect of adrenergic agonists [see WARNINGS AND PRECAUTIONS ( 5.7 )]. 7.3 Non-potassium Sparing Diuretics The ECG changes and/or hypokalemia that may result from the administration of non-potassium sparing diuretics (such as loop or thiazide diuretics) can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is not known, caution is advised in the co-administration of beta-agonists with non-potassium sparing diuretics. 7.4 MAO Inhibitors, Tricyclic Antidepressants, QTc Prolonging Drugs Formoterol, as with other beta 2 -agonists, should be administered with extreme caution to patients being treated with monoamine oxidase inhibitors, tricyclic antidepressants, or drugs known to prolong the QTc interval because the effect of adrenergic agonists on the cardiovascular system may be potentiated by these agents. Drugs that are known to prolong the QTc interval have an increased risk of ventricular arrhythmias. 7.5 Beta-blockers Beta-adrenergic receptor antagonists (beta-blockers) and formoterol may inhibit the effect of each other when administered concurrently. Beta-blockers not only block the therapeutic effects of beta-agonists, but may produce severe bronchospasm in COPD patients. Therefore, patients with COPD should not normally be treated with beta-blockers. However, under certain circumstances, e.g., as prophylaxis after myocardial infarction, there may be no acceptable alternatives to the use of beta-blockers in patients with COPD. In this setting, cardioselective beta-blockers could be considered, although they should be administered with caution.