RELENZA

1 INDICATIONS AND USAGE RELENZA, an influenza virus neuraminidase inhibitor (NAI), is indicated for: Treatment of acute, uncomplicated influenza type A and B infections in patients aged 7 years and older who have been symptomatic for no more than 2 days. ( 1.1 ) Prophylaxis of influenza in patients aged 5 years and older. ( 1.2 ) Important Limitations of Use: Not recommended for treatment or prophylaxis of influenza in: • Individuals with underlying airways disease. ( 5.1 ) Not proven effective for: • Treatment in individuals with underlying airways disease. ( 1.3 ) • Prophylaxis in nursing home residents. ( 1.3 ) Not a substitute for annual influenza vaccination. ( 1.3 ) Consider available information on influenza drug susceptibility patterns and treatment effects when deciding whether to use RELENZA. ( 1.3 ) 1.1 Treatment of Influenza RELENZA (zanamivir) inhalation powder is indicated for treatment of uncomplicated acute illness due to influenza A and B virus in adults and pediatric patients aged 7 years and older who have been symptomatic for no more than 2 days. 1.2 Prophylaxis of Influenza RELENZA is indicated for prophylaxis of influenza in adults and pediatric patients aged 5 years and older. 1.3 Important Limitations of Use • RELENZA is not recommended for treatment or prophylaxis of influenza in individuals with underlying airways disease (such as asthma or chronic obstructive pulmonary disease) due to risk of serious bronchospasm [see Warnings and Precautions ( 5.1 )] . • RELENZA has not been proven effective for treatment of influenza in individuals with underlying airways disease. • RELENZA has not been proven effective for prophylaxis of influenza in the nursing home setting. • RELENZA is not a substitute for early influenza vaccination on an annual basis as recommended by the Centers for Disease Control's Immunization Practices Advisory Committee. • Influenza viruses change over time. Emergence of resistance mutations could decrease drug effectiveness. Other factors (for example, changes in viral virulence) might also diminish clinical benefit of antiviral drugs. Prescribers should consider available information on influenza drug susceptibility patterns and treatment effects when deciding whether to use RELENZA. • There is no evidence for efficacy of zanamivir in any illness caused by agents other than influenza virus A and B. • Patients should be advised that the use of RELENZA for treatment of influenza has not been shown to reduce the risk of transmission of influenza to others.

2 DOSAGE AND ADMINISTRATION Indication Dose Treatment of Influenza ( 2.2 ) 10 mg twice daily for 5 days Prophylaxis: ( 2.3 ) Household Setting 10 mg once daily for 10 days Community Outbreaks 10 mg once daily for 28 days Note: The 10-mg dose is provided by 2 inhalations (one 5-mg blister per inhalation). ( 2.1 ) 2.1 Dosing Considerations • RELENZA is for administration to the respiratory tract by oral inhalation only , using the DISKHALER device provided [see Warnings and Precautions ( 5.6 )] . • The 10-mg dose is provided by 2 inhalations (one 5-mg blister per inhalation). • Patients should be instructed in the use of the delivery system. Instructions should include a demonstration whenever possible. If RELENZA is prescribed for children, it should be used only under adult supervision and instruction, and the supervising adult should first be instructed by a healthcare professional [see Patient Counseling Information ( 17 )] . • Patients scheduled to use an inhaled bronchodilator at the same time as RELENZA should use their bronchodilator before taking RELENZA [see Patient Counseling Information ( 17 )] . 2.2 Treatment of Influenza • The recommended dose of RELENZA for treatment of influenza in adults and pediatric patients aged 7 years and older is 10 mg twice daily (approximately 12 hours apart) for 5 days. • Two doses should be taken on the first day of treatment whenever possible provided there is at least 2 hours between doses. • On subsequent days, doses should be about 12 hours apart (e.g., morning and evening) at approximately the same time each day. • The safety and efficacy of repeated treatment courses have not been studied. 2.3 Prophylaxis of Influenza Household Setting • The recommended dose of RELENZA for prophylaxis of influenza in adults and pediatric patients aged 5 years and older in a household setting is 10 mg once daily for 10 days. • The dose should be administered at approximately the same time each day. • There are no data on the effectiveness of prophylaxis with RELENZA in a household setting when initiated more than 1.5 days after the onset of signs or symptoms in the index case. Community Outbreaks • The recommended dose of RELENZA for prophylaxis of influenza in adults and adolescents in a community setting is 10 mg once daily for 28 days. • The dose should be administered at approximately the same time each day. • There are no data on the effectiveness of prophylaxis with RELENZA in a community outbreak when initiated more than 5 days after the outbreak was identified in the community. • The safety and effectiveness of prophylaxis with RELENZA have not been evaluated for longer than 28 days’ duration.

4 CONTRAINDICATIONS RELENZA is contraindicated in patients with history of allergic reaction to any ingredient of RELENZA, including milk proteins [see Warnings and Precautions ( 5.2 ), Description ( 11 )] . Do not use in patients with history of allergic reaction to any ingredient of RELENZA, including milk proteins. ( 4 )

5 WARNINGS AND PRECAUTIONS • Bronchospasm: Serious, sometimes fatal, cases have occurred. Not recommended in individuals with underlying airways disease. Discontinue RELENZA if bronchospasm or decline in respiratory function develops. ( 5.1 ) • Allergic Reactions: Discontinue RELENZA and initiate appropriate treatment if an allergic reaction occurs or is suspected. ( 5.2 ) • Neuropsychiatric Events: Patients with influenza, particularly pediatric patients, may be at an increased risk of seizures, confusion, or abnormal behavior early in their illness. Monitor for signs of abnormal behavior. ( 5.3 ) • High-Risk Underlying Medical Conditions: Safety and effectiveness have not been demonstrated in these patients. ( 5.4 ) 5.1 Bronchospasm RELENZA is not recommended for treatment or prophylaxis of influenza in individuals with underlying airways disease (such as asthma or chronic obstructive pulmonary disease). Serious cases of bronchospasm, including fatalities, have been reported during treatment with RELENZA in patients with and without underlying airways disease. Many of these cases were reported during postmarketing and causality was difficult to assess. RELENZA should be discontinued in any patient who develops bronchospasm or decline in respiratory function; immediate treatment and hospitalization may be required. Some patients without prior pulmonary disease may also have respiratory abnormalities from acute respiratory infection that could resemble adverse drug reactions or increase patient vulnerability to adverse drug reactions. Bronchospasm was documented following administration of zanamivir in 1 of 13 subjects with mild or moderate asthma (but without acute influenza‑like illness) in a Phase 1 trial. In a Phase 3 trial in subjects with acute influenza‑like illness superimposed on underlying asthma or chronic obstructive pulmonary disease, 10% (24 of 244) of subjects on zanamivir and 9% (22 of 237) on placebo experienced a greater than 20% decline in forced expiratory volume in 1 second (FEV 1 ) following treatment for 5 days. If use of RELENZA is considered for a patient with underlying airways disease, the potential risks and benefits should be carefully weighed. If a decision is made to prescribe RELENZA for such a patient, this should be done only under conditions of careful monitoring of respiratory function, close observation, and appropriate supportive care, including availability of fast‑acting bronchodilators. 5.2 Allergic Reactions Allergic-like reactions, including oropharyngeal edema, serious skin rashes, and anaphylaxis have been reported in postmarketing experience with RELENZA. RELENZA should be stopped and appropriate treatment instituted if an allergic reaction occurs or is suspected. 5.3 Neuropsychiatric Events Influenza can be associated with a variety of neurologic and behavioral symptoms which can include events such as seizures, hallucinations, delirium, and abnormal behavior, in some cases resulting in fatal outcomes. These events may occur in the setting of encephalitis or encephalopathy but can occur without obvious severe disease. There have been postmarketing reports of delirium and abnormal behavior leading to injury in patients with influenza who were receiving neuraminidase inhibitors (NAIs), including RELENZA. Because these events were reported voluntarily during clinical practice, estimates of frequency cannot be made, but they appear to be uncommon based on usage data for RELENZA. These events were reported primarily among pediatric patients and often had an abrupt onset and rapid resolution. The contribution of RELENZA to these events has not been established. Patients with influenza should be closely monitored for signs of abnormal behavior. If neuropsychiatric symptoms occur, the risks and benefits of continuing treatment should be evaluated for each patient. 5.4 Limitations of Populations Studied Safety and efficacy have not been demonstrated in patients with high-risk underlying medical conditions. No information is available regarding treatment of influenza in patients with any medical condition sufficiently severe or unstable to be considered at imminent risk of requiring inpatient management. 5.5 Bacterial Infections Serious bacterial infections may begin with influenza-like symptoms or may coexist with or occur as complications during the course of influenza. RELENZA has not been shown to prevent such complications. 5.6 Importance of Proper Route of Administration RELENZA inhalation powder must not be made into an extemporaneous solution for administration by nebulization or mechanical ventilation. There have been reports of hospitalized patients with influenza who received a solution made with RELENZA inhalation powder administered by nebulization or mechanical ventilation, including a fatal case where it was reported that the lactose in this formulation obstructed the proper functioning of the equipment. RELENZA inhalation powder must only be administered using the device provided [see Dosage and Administration ( 2.1 )] . 5.7 Importance of Proper Use of DISKHALER Effective and safe use of RELENZA requires proper use of the DISKHALER to inhale the drug. Prescribers should carefully evaluate the ability of young children to use the delivery system if use of RELENZA is considered [see Use in Specific Populations ( 8.4 )].

7 DRUG INTERACTIONS The concurrent use of RELENZA with live attenuated influenza vaccine (LAIV) intranasal has not been evaluated. However, because of potential interference between these products, LAIV should not be administered within 2 weeks before or 48 hours after administration of RELENZA, unless medically indicated. The concern about possible interference arises from the potential for antiviral drugs to inhibit replication of live vaccine virus. Trivalent inactivated influenza vaccine can be administered at any time relative to use of RELENZA [see Microbiology ( 12.4 )] . Live attenuated influenza vaccine, intranasal ( 7 ): • Do not administer until 48 hours following cessation of RELENZA. • Do not administer RELENZA until 2 weeks following administration of the live attenuated influenza vaccine, unless medically indicated.

6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the labeling: • Bronchospasm [see Warnings and Precautions ( 5.1 )] . • Safety information in patients with underlying airways disease [see Warnings and Precautions ( 5.1 )]. • Allergic-like reactions [see Warnings and Precautions ( 5.2 )] . The most common adverse events reported in greater than 1.5% of subjects treated with RELENZA and more commonly than in subjects treated with placebo are: • Treatment Trials – sinusitis, dizziness. ( 6.1 ) • Prophylaxis Trials – fever and/or chills, arthralgia, and articular rheumatism. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact GlaxoSmithKline at 1-888-825-5249 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 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 with rates in the clinical trials of another drug and may not reflect the rates observed in practice. The placebo used in clinical trials consisted of inhaled lactose powder, which is also the vehicle for the active drug; therefore, some adverse events occurring at similar frequencies in different treatment groups could be related to lactose vehicle inhalation. Treatment of Influenza Clinical Trials in Adults and Adolescents: Adverse events that occurred with an incidence greater than or equal to 1.5% in treatment trials are listed in Table 1. This table shows adverse events occurring in subjects aged 12 years and older receiving RELENZA 10 mg inhaled twice daily, RELENZA in all inhalation regimens, and placebo inhaled twice daily (where placebo consisted of the same lactose vehicle used in RELENZA). Table 1. Summary of Adverse Events ≥1.5% Incidence during Treatment in Adults and Adolescents a Includes trials where RELENZA was administered intranasally (6.4 mg 2 to 4 times per day in addition to inhaled preparation) and/or inhaled more frequently (q.i.d.) than the currently recommended dose. Adverse Event RELENZA Placebo (Lactose Vehicle) (n = 1,520) 10 mg b.i.d. Inhaled (n = 1,132) All Dosing Regimens a (n = 2,289) Body as a whole Headaches 2% 2% 3% Digestive Diarrhea 3% 3% 4% Nausea 3% 3% 3% Vomiting 1% 1% 2% Respiratory Nasal signs and symptoms 2% 3% 3% Bronchitis 2% 2% 3% Cough 2% 2% 3% Sinusitis 3% 2% 2% Ear, nose, and throat infections 2% 1% 2% Nervous system Dizziness 2% 1% <1% Additional adverse reactions occurring in less than 1.5% of subjects receiving RELENZA included malaise, fatigue, fever, abdominal pain, myalgia, arthralgia, and urticaria. The most frequent laboratory abnormalities in Phase 3 treatment trials included elevations of liver enzymes and creatine phosphokinase (CPK), lymphopenia, and neutropenia. These were reported in similar proportions of zanamivir and lactose vehicle placebo recipients with acute influenza‑like illness. Clinical Trials in Pediatric Subjects: Adverse events that occurred with an incidence greater than or equal to 1.5% in children receiving treatment doses of RELENZA in 2 Phase 3 trials are listed in Table 2 . This table shows adverse events occurring in pediatric subjects aged 5 to 12 years receiving RELENZA 10 mg inhaled twice daily and placebo inhaled twice daily (where placebo consisted of the same lactose vehicle used in RELENZA). Table 2. Summary of Adverse Events ≥1.5% Incidence during Treatment in Pediatric Subjects a a Includes a subset of subjects receiving RELENZA for treatment of influenza in a prophylaxis trial. Adverse Event RELENZA 10 mg b.i.d. Inhaled (n = 291) Placebo (Lactose Vehicle) (n = 318) Respiratory Ear, nose, and throat infections 5% 5% Ear, nose, and throat hemorrhage <1% 2% Asthma <1% 2% Cough <1% 2% Digestive Vomiting 2% 3% Diarrhea 2% 2% Nausea <1% 2% In 1 of the 2 trials described in Table 2 , some additional information is available from children (aged 5 to 12 years) without acute influenza-like illness who received an investigational prophylaxis regimen of RELENZA; 132 children received RELENZA and 145 children received placebo. Among these children, nasal signs and symptoms (zanamivir 20%, placebo 9%), cough (zanamivir 16%, placebo 8%), and throat/tonsil discomfort and pain (zanamivir 11%, placebo 6%) were reported more frequently with RELENZA than placebo. In a subset with chronic pulmonary disease, lower respiratory adverse events (described as asthma, cough, or viral respiratory infections which could include influenza-like symptoms) were reported in 7 of 7 zanamivir recipients and 5 of 12 placebo recipients. Prophylaxis of Influenza Family/Household Prophylaxis Trials: Adverse events that occurred with an incidence of greater than or equal to 1.5% in the 2 prophylaxis trials are listed in Table 3 . This table shows adverse events occurring in subjects aged 5 years and older receiving RELENZA 10 mg inhaled once daily for 10 days. Table 3. Summary of Adverse Events ≥1.5% Incidence during 10-Day Prophylaxis Trials in Adults, Adolescents, and Children a a In prophylaxis trials, symptoms associated with influenza-like illness were captured as adverse events; subjects were enrolled during a winter respiratory season during which time any symptoms that occurred were captured as adverse events. Adverse Event Contact Cases RELENZA (n = 1,068) Placebo (n = 1,059) Lower respiratory Viral respiratory infections 13% 19% Cough 7% 9% Neurologic Headaches 13% 14% Ear, nose, and throat Nasal signs and symptoms 12% 12% Throat and tonsil discomfort and pain 8% 9% Nasal inflammation 1% 2% Musculoskeletal Muscle pain 3% 3% Endocrine and metabolic Feeding problems (decreased or increased appetite and anorexia) 2% 2% Gastrointestinal Nausea and vomiting 1% 2% Non-site specific Malaise and fatigue 5% 5% Temperature regulation disturbances (fever and/or chills) 5% 4% Community Prophylaxis Trials: Adverse events that occurred with an incidence of greater than or equal to 1.5% in 2 prophylaxis trials are listed in Table 4 . This table shows adverse events occurring in subjects aged 5 years and older receiving RELENZA 10 mg inhaled once daily for 28 days. Table 4. Summary of Adverse Events ≥1.5% Incidence during 28-Day Prophylaxis Trials in Adults, Adolescents, and Children a a In prophylaxis trials, symptoms associated with influenza-like illness were captured as adverse events; subjects were enrolled during a winter respiratory season during which time any symptoms that occurred were captured as adverse events. Adverse Event RELENZA (n = 2,231) Placebo (n = 2,239) Neurologic Headaches 24% 26% Ear, nose, and throat Throat and tonsil discomfort and pain 19% 20% Nasal signs and symptoms 12% 13% Ear, nose, and throat infections 2% 2% Lower respiratory Cough 17% 18% Viral respiratory infections 3% 4% Musculoskeletal Muscle pain 8% 8% Musculoskeletal pain 6% 6% Arthralgia and articular rheumatism 2% <1% Endocrine and metabolic Feeding problems (decreased or increased appetite and anorexia) 4% 4% Gastrointestinal Nausea and vomiting 2% 3% Diarrhea 2% 2% Non-site specific Temperature regulation disturbances (fever and/or chills) 9% 10% Malaise and fatigue 8% 8% 6.2 Postmarketing Experience The following adverse reactions have been identified during postapproval use of RELENZA. 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. Allergic Reactions Allergic or allergic-like reaction, including oropharyngeal edema [see Warnings and Precautions ( 5.2 )] . Psychiatric Delirium, including symptoms such as altered level of consciousness, confusion, abnormal behavior, delusions, hallucinations, agitation, anxiety, nightmares [see Warnings and Precautions ( 5.3 )]. Cardiac Arrhythmias, syncope. Neurologic Seizures. Vasovagal-like episodes have been reported shortly following inhalation of zanamivir. Respiratory Bronchospasm, dyspnea [see Warnings and Precautions ( 5.1 )] . Skin Facial edema; rash, including serious cutaneous reactions (e.g., erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis); urticaria [see Warnings and Precautions ( 5.2 )] .

8.1 Pregnancy Risk Summary Available data from published studies suggest that use of RELENZA during pregnancy is not associated with an increased risk of birth defects or adverse maternal or fetal outcomes. However, these studies are limited by their small sample sizes, which preclude a definitive assessment of the risk (see Data). There are risks to the mother and fetus associated with influenza infection in pregnancy (see Clinical Considerations) . In animal reproduction studies, no adverse developmental effects were observed with intravenous or subcutaneous administration of zanamivir at exposures 300 and 150 times, respectively, the systemic exposure at the maximum recommended human inhalation dose (MRHID) of 10 mg twice daily (see Data) . The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk: Pregnant women are at higher risk of severe complications from influenza, which may lead to adverse pregnancy and/or fetal outcomes, including maternal death, stillbirths, birth defects, preterm delivery, low birth weight, and small for gestational age. Data Human Data: A study of population-based registers from Denmark, Norway, Sweden, and France reported outcomes of 5,824 pregnant women who filled a prescription for an NAI compared with outcomes in unexposed pregnant women in the general population. This study included 1,560 women who filled a prescription for zanamivir (including 321 first trimester exposures). Although no specific analyses were conducted for zanamivir, exposure to the NAI class in utero was not associated with major birth defects, preterm birth, low birth weight, small for gestational age, still birth, neonatal morbidity, or neonatal mortality. A few published studies compared outcomes of pregnant women exposed to zanamivir with outcomes in various comparator cohorts. These studies suggested no increased risk of major birth defects, preterm birth, or low birth weight. Sample sizes in these studies ranged from 50 to 180 pregnant women exposed to zanamivir, including 15 to 44 women exposed in the first trimester. Limitations of available studies include the lack of specific analyses for zanamivir, possible exposure and outcome misclassification, and small sample sizes. These limitations preclude a definitive assessment of the risk. Animal Data: Zanamivir was administered intravenously to pregnant rats and rabbits at 1, 9, or 90 mg/kg/day during organogenesis (gestation Day 6 to 15 [rat] and 7 to 19 [rabbit]). No adverse maternal or embryo-fetal effects were observed up to the highest intravenous dose of zanamivir (90 mg/kg/day), resulting in systemic drug exposure (AUC) estimated from both rats and rabbits, 300 times the exposure at the MRHID. In a separate study, zanamivir was administered subcutaneously to pregnant rats at 3, 27, and 240 mg/kg/day in three divided doses during organogenesis (gestation Day 7 to 17). An increased incidence of skeletal and visceral alterations and variants was observed at the high dose (240 mg/kg/day). No adverse maternal or embryo-fetal effects were observed at the middle dose (27 mg/kg/day), resulting in systemic drug exposure (AUC) 150 times the exposure at the MRHID. In prenatal and postnatal development studies in rats, zanamivir was administered intravenously at 1, 9, or 90 mg/kg/day during organogenesis (gestation Day 0 to 19) or from late gestation through delivery and lactation (gestation Day 16 to post-partum/lactation Day 21). No significant effects were observed in the offspring at systemic drug exposures (AUC) estimated to be 300 times the exposure at the MRHID. Zanamivir distributed across the placenta in pregnant rats and rabbits, with less than 0.04% of the administered maternal dose being recovered from the fetus on gestation Day 12.