TOBRAMYCIN: 11,597 Adverse Event Reports & Safety Profile

TOBI Podhaler consists of a dry powder formulation of tobramycin for oral inhalation only with the Podhaler device. The inhalation powder is filled into clear, colorless hypromellose capsules. Each clear, colorless hypromellose capsule contains a spray dried powder of 28 mg of tobramycin active ingredient with 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), calcium chloride, and sulfuric acid (for pH adjustment). The active component of TOBI Podhaler is tobramycin. Tobramycin is an aminoglycoside antibiotic. Its chemical name is O -3-amino-3-deoxy-α-D-glucopyranosyl-(1→4)- O -[2,6-diamino-2,3,6-trideoxy-α-D-ribo-hexopyranosyl-(1→6)]-2-deoxy-L-streptamine; its structural formula is: Tobramycin has a molecular weight of 467.52, and its empirical formula is C 18 H 37 N 5 O 9 . Tobramycin is a white to almost white powder; visually free from any foreign contaminants. Tobramycin is freely soluble in water, very slightly soluble in ethanol, and practically insoluble in chloroform and ether.

The

Podhaler device is a plastic device used to inhale the dry powder contained in the TOBI Podhaler capsule. Under standardized in vitro testing at a fixed flow rate of 60 L/min and volume of 2 L for 2 seconds, the Podhaler device has a target delivered dose of 102 mg of tobramycin from the mouthpiece (4 capsules per dose). Peak inspiratory flow rate and inhaled volumes were explored in 96 cystic fibrosis patients aged 6 years and older. Older patients with significant disease progression and associated decreases in forced expiratory volume (FEV 1 ) and younger patients with inhaled volumes <1 L were able to generate inspiratory flow rates and volumes required to receive their medication when following the instructions for use. However, no pediatric patients aged 6 to 10 years with FEV 1 less than 40% predicted were evaluated. Tobramycin structural formula

AND USAGE Tobramycin for Injection, is an aminoglycoside antibacterial indicated for the treatment of serious bacterial infections caused by susceptible isolates of the designated bacteria in the diseases listed below ( 1.1 ): Septicemia in the pediatric patient and adults caused by P. aeruginosa , E. coli , and Klebsiella species (spp). Lower respiratory tract infections caused by P. aeruginosa, Klebsiella spp, Enterobacter spp, Serratia spp, E. coli, and S. aureus Serious central nervous system infections (meningitis) caused by susceptible organisms. Intra-abdominal infections, including peritonitis, caused by E. coli, Klebsiella spp., and Enterobacter spp. Skin, bone, and skin structure infections caused by P. aeruginosa, Proteus spp, E. coli, Klebsiella spp., Enterobacter spp., and S. aureus. Complicated urinary tract infections caused by P. aeruginosa , Proteus spp., (indole-positive and indole-negative), E. coli , Klebsiella spp., Enterobacter spp., Serratia spp., S. aureus , Providencia spp., and Citrobacter spp. To reduce the development of drug-resistant bacteria and maintain the effectiveness of Tobramycin for Injection and other antibacterial drugs, Tobramycin for Injection should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria ( 1.2 ).

1.1 Septicemia Tobramycin for Injection is indicated for the treatment of septicemia caused by susceptible isolates of P. aeruginosa, E. coli, and Klebsiella spp., in adult and pediatric patients.

1.2 Lower Respiratory Tract Infections Tobramycin for Injection is indicated for the treatment of lower respiratory tract infections caused by susceptible isolates of P. aeruginosa, Klebsiella spp., Enterobacter spp., Serratia spp., E. coli, and S. aureus in adult and pediatric patients.

1.3 Central Nervous System Infections (Meningitis) Tobramycin for Injection is indicated for the treatment of bacterial meningitis caused by susceptible bacteria in adult and pediatric patients.

1.4 Intra-abdominal Infections Tobramycin for Injection is indicated for the treatment of intra-abdominal infections, including peritonitis, caused by susceptible isolates of E. coli, Klebsiella spp., and Enterobacter spp. in adult and pediatric patients.

1.5 Skin and Skin Structure Infections Tobramycin for Injection is indicated for the treatment of skin and skin structure infections caused by susceptible isolates of P. aeruginosa, Proteus spp., E. coli, Klebsiella spp., Enterobacter spp., and S. aureus in adult and pediatric patients.

1.6 Bone Infections Tobramycin for Injection is indicated for the treatment of bone infections caused by susceptible isolates of P. aeruginosa, Proteus spp., E. coli, Klebsiella spp., Enterobacter spp., and S. aureus in adult and pediatric patients

1.7 Complicated and Recurrent Urinary Tract Infections Tobramycin for Injection is indicated for the treatment of complicated urinary tract infections caused by susceptible isolates of P. aeruginosa, Proteus spp., (indole-positive and indole-negative), E. coli, Klebsiella spp., Enterobacter spp., Serratia spp., S. aureus, Providencia spp., and Citrobacter spp. in adult and pediatric patients

1.8 Usage To reduce the development of drug-resistant bacteria and maintain the effectiveness of Tobramycin for Injection and other antibacterial drugs, Tobramycin for Injection should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

DOSAGE AND ADMINISTRATION: Tobramycin may be given intramuscularly or intravenously. Recommended dosages are the same for both routes. The patient’s pretreatment body weight should be obtained for calculation of correct dosage. It is desirable to measure both peak and trough serum concentrations (see WARNINGS box and PRECAUTIONS ). Administration for Patients with Normal Renal Function Adults with Serious Infections: 3 mg/kg/day in 3 equal doses every 8 hours (see Table 3).

Adults With

Life-Threatening Infections: Up to 5 mg/kg/day may be administered in 3 or 4 equal doses (see Table 3). The dosage should be reduced to 3 mg/kg/day as soon as clinically indicated. To prevent increased toxicity due to excessive blood levels, dosage should not exceed 5 mg/kg/day unless serum levels are monitored (see WARNINGS box and PRECAUTIONS ).

Table

3 DOSAGE SCHEDULE GUIDE FOR ADULTS WITH NORMAL RENAL FUNCTION (Dosage at 8-Hour Intervals)

For Patient Weighing Usual

Dose for Serious Infections Maximum Dose for Life-Threatening Infections (Reduce as soon as possible) 1 mg/kg q8h 1.66 mg/kg q8h kg lb (Total, 3 mg/kg/day) (Total, 5 mg/kg/day) mg/dose mL/dose* mg/dose mL/dose* q8h q8h 120 264 120 mg 3 mL 200 mg 5 mL 115 253 115 mg 2.9 mL 191 mg 4.75 mL 110 242 110 mg 2.75 mL 183 mg 4.5 mL 105 231 105 mg 2.6 mL 175 mg 4.4 mL 100 220 100 mg 2.5 mL 166 mg 4.2 mL 95 209 95 mg 2.4 mL 158 mg 4 mL 90 198 90 mg 2.25 mL 150 mg 3.75 mL 85 187 85 mg 2.1 mL 141 mg 3.5 mL 80 176 80 mg 2 mL 133 mg 3.3 mL 75 165 75 mg 1.9 mL 125 mg 3.1 mL 70 154 70 mg 1.75 mL 116 mg 2.9 mL 65 143 65 mg 1.6 mL 108 mg 2.7 mL 60 132 60 mg 1.5 mL 100 mg 2.5 mL 55 121 55 mg 1.4 mL 91 mg 2.25 mL 50 110 50 mg 1.25 mL 83 mg 2.1 mL 45 99 45 mg 1.1 mL 75 mg 1.9 mL 40 88 40 mg 1 mL 66 mg 1.6 mL *Applicable to all product forms except Tobramycin Injection Pediatric, 10 mg/mL (see HOW SUPPLIED ).

Pediatric

Patients (greater than 1 week of age): 6 to 7.5 mg/kg/day in 3 or 4 equally divided doses (2 to 2.5 mg/kg every 8 hours or 1.5 to 1.89 mg/kg every 6 hours). Premature or Full-Term Neonates 1 Week of Age or Less: Up to 4 mg/kg/day may be administered in 2 equal doses every 12 hours. It is desirable to limit treatment to a short term. The usual duration of treatment is 7 to 10 days. A longer course of therapy may be necessary in difficult and complicated infections. In such cases, monitoring of renal, auditory, and vestibular functions is advised, because neurotoxicity is more likely to occur when treatment is extended longer than 10 days. Dosage in Patients with Cystic Fibrosis In patients with cystic fibrosis, altered pharmacokinetics may result in reduced serum concentrations of aminoglycosides. Measurement of tobramycin serum concentration during treatment is especially important as a basis for determining appropriate dose. In patients with severe cystic fibrosis, an initial dosing regimen of 10 mg/kg/day in 4 equally divided doses is recommended. This dosing regimen is suggested only as a guide. The serum levels of tobramycin should be measured directly during treatment due to wide interpatient variability. Administration for Patients with Impaired Renal Function Whenever possible, serum tobramycin concentrations should be monitored during therapy. Following a loading dose of 1 mg/kg, subsequent dosage in these patients must be adjusted, either with reduced doses administered at 8-hour intervals or with normal doses given at prolonged intervals. Both of these methods are suggested as guides to be used when serum levels of tobramycin cannot be measured directly. They are based on either the creatinine clearance level or the serum creatinine level of the patient because these values correlate with the half-life of tobramycin. The dosage schedule derived from either method should be used in conjunction with careful clinical and laboratory observations of the patient and should be modified as necessary. Neither method should be used when dialysis is being performed. Reduced dosage at 8-hour intervals : When the creatinine clearance rate is 70 mL or less per minute or when the serum creatinine value is known, the amount of the reduced dose can be determined by multiplying the normal dose from Table 3 by the percent of normal dose from the accompanying nomogram. * Scales have been adjusted to facilitate dosage calculations. An alternate rough guide for determining reduced dosage at 8-hour intervals (for patients whose steady-state serum creatinine values are known) is to divide the normally recommended dose by the patient’s serum creatinine. Normal dosage at prolonged intervals : If the creatinine clearance rate is not available and the patient’s condition is stable, a dosage frequency in hours for the dosage given in Table 3 can be determined by multiplying the patient’s serum creatinine by 6. nomogram Dosage in Obese Patients The appropriate dose may be calculated by using the patient’s estimated lean body weight plus 40% of the excess as the basic weight on which to figure mg/kg.

Intramuscular Administration

Tobramycin may be administered by withdrawing the appropriate dose directly from a vial.

Intravenous Administration

For intravenous administration, the usual volume of diluent (0.9% Sodium Chloride Injection or 5% Dextrose Injection) is 50 to 100 mL for adult doses. For pediatric patients, the volume of diluent should be proportionately less than that for adults. The diluted solution usually should be infused over a period of 20 to 60 minutes. Infusion periods of less than 20 minutes are not recommended because peak serum levels may exceed 12 mcg/mL (see WARNINGS box). Tobramycin injection should not be physically premixed with other drugs but should be administered separately according to the recommended dose and route. Prior to administration, parenteral drug products should be inspected visually for particulate matter and discoloration whenever solution and container permit.

Administration for Patients with Normal Renal Function Adults with Serious Infections: 3 mg/kg/day in 3 equal doses every 8 hours (see Table 3).

Adults With

Life-Threatening Infections: Up to 5 mg/kg/day may be administered in 3 or 4 equal doses (see Table 3). The dosage should be reduced to 3 mg/kg/day as soon as clinically indicated. To prevent increased toxicity due to excessive blood levels, dosage should not exceed 5 mg/kg/day unless serum levels are monitored (see WARNINGS box and PRECAUTIONS ).

Table

3 DOSAGE SCHEDULE GUIDE FOR ADULTS WITH NORMAL RENAL FUNCTION (Dosage at 8-Hour Intervals)

For Patient Weighing Usual

Dose for Serious Infections Maximum Dose for Life-Threatening Infections (Reduce as soon as possible) 1 mg/kg q8h 1.66 mg/kg q8h kg lb (Total, 3 mg/kg/day) (Total, 5 mg/kg/day) mg/dose mL/dose* mg/dose mL/dose* q8h q8h 120 264 120 mg 3 mL 200 mg 5 mL 115 253 115 mg 2.9 mL 191 mg 4.75 mL 110 242 110 mg 2.75 mL 183 mg 4.5 mL 105 231 105 mg 2.6 mL 175 mg 4.4 mL 100 220 100 mg 2.5 mL 166 mg 4.2 mL 95 209 95 mg 2.4 mL 158 mg 4 mL 90 198 90 mg 2.25 mL 150 mg 3.75 mL 85 187 85 mg 2.1 mL 141 mg 3.5 mL 80 176 80 mg 2 mL 133 mg 3.3 mL 75 165 75 mg 1.9 mL 125 mg 3.1 mL 70 154 70 mg 1.75 mL 116 mg 2.9 mL 65 143 65 mg 1.6 mL 108 mg 2.7 mL 60 132 60 mg 1.5 mL 100 mg 2.5 mL 55 121 55 mg 1.4 mL 91 mg 2.25 mL 50 110 50 mg 1.25 mL 83 mg 2.1 mL 45 99 45 mg 1.1 mL 75 mg 1.9 mL 40 88 40 mg 1 mL 66 mg 1.6 mL *Applicable to all product forms except Tobramycin Injection Pediatric, 10 mg/mL (see HOW SUPPLIED ).

Pediatric

Patients (greater than 1 week of age): 6 to 7.5 mg/kg/day in 3 or 4 equally divided doses (2 to 2.5 mg/kg every 8 hours or 1.5 to 1.89 mg/kg every 6 hours). Premature or Full-Term Neonates 1 Week of Age or Less: Up to 4 mg/kg/day may be administered in 2 equal doses every 12 hours. It is desirable to limit treatment to a short term. The usual duration of treatment is 7 to 10 days. A longer course of therapy may be necessary in difficult and complicated infections. In such cases, monitoring of renal, auditory, and vestibular functions is advised, because neurotoxicity is more likely to occur when treatment is extended longer than 10 days.

Dosage in Patients with Cystic Fibrosis In patients with cystic fibrosis, altered pharmacokinetics may result in reduced serum concentrations of aminoglycosides. Measurement of tobramycin serum concentration during treatment is especially important as a basis for determining appropriate dose. In patients with severe cystic fibrosis, an initial dosing regimen of 10 mg/kg/day in 4 equally divided doses is recommended. This dosing regimen is suggested only as a guide. The serum levels of tobramycin should be measured directly during treatment due to wide interpatient variability.

Administration for Patients with Impaired Renal Function Whenever possible, serum tobramycin concentrations should be monitored during therapy. Following a loading dose of 1 mg/kg, subsequent dosage in these patients must be adjusted, either with reduced doses administered at 8-hour intervals or with normal doses given at prolonged intervals. Both of these methods are suggested as guides to be used when serum levels of tobramycin cannot be measured directly. They are based on either the creatinine clearance level or the serum creatinine level of the patient because these values correlate with the half-life of tobramycin. The dosage schedule derived from either method should be used in conjunction with careful clinical and laboratory observations of the patient and should be modified as necessary. Neither method should be used when dialysis is being performed. Reduced dosage at 8-hour intervals : When the creatinine clearance rate is 70 mL or less per minute or when the serum creatinine value is known, the amount of the reduced dose can be determined by multiplying the normal dose from Table 3 by the percent of normal dose from the accompanying nomogram. * Scales have been adjusted to facilitate dosage calculations. An alternate rough guide for determining reduced dosage at 8-hour intervals (for patients whose steady-state serum creatinine values are known) is to divide the normally recommended dose by the patient’s serum creatinine. Normal dosage at prolonged intervals : If the creatinine clearance rate is not available and the patient’s condition is stable, a dosage frequency in hours for the dosage given in Table 3 can be determined by multiplying the patient’s serum creatinine by 6. nomogram

Dosage in Obese Patients The appropriate dose may be calculated by using the patient’s estimated lean body weight plus 40% of the excess as the basic weight on which to figure mg/kg.

Intramuscular Administration

Tobramycin may be administered by withdrawing the appropriate dose directly from a vial.

Intravenous Administration

For intravenous administration, the usual volume of diluent (0.9% Sodium Chloride Injection or 5% Dextrose Injection) is 50 to 100 mL for adult doses. For pediatric patients, the volume of diluent should be proportionately less than that for adults. The diluted solution usually should be infused over a period of 20 to 60 minutes. Infusion periods of less than 20 minutes are not recommended because peak serum levels may exceed 12 mcg/mL (see WARNINGS box). Tobramycin injection should not be physically premixed with other drugs but should be administered separately according to the recommended dose and route. Prior to administration, parenteral drug products should be inspected visually for particulate matter and discoloration whenever solution and container permit.

CONTRAINDICATIONS: A hypersensitivity to any aminoglycoside is a contraindication to the use of tobramycin. A history of hypersensitivity or serious toxic reactions to aminoglycosides may also contraindicate the use of any other aminoglycoside because of the known cross-sensitivity of patients to drugs in this class.

REACTIONS The most common adverse reactions (≥10 % of TOBI Podhaler and TOBI patients in primary safety population) are cough, lung disorder, productive cough, dyspnea, pyrexia, oropharyngeal pain, dysphonia, hemoptysis, and headache ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Mylan at 1-877-446-3679 (1-877-4-INFO-RX) 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 to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Tobi

Podhaler has been evaluated for safety in 425 cystic fibrosis patients exposed to at least one dose of TOBI Podhaler, including 273 patients who were exposed across three cycles (6 months) of treatment. Each cycle consisted of 28 days on-treatment (with 112 mg administered twice-daily) and 28 days off-treatment. Patients with serum creatinine ≥2 mg/dL and blood urea nitrogen (BUN) ≥40 mg/dL were excluded from clinical studies. There were 218 males and 207 females in this population, and reflecting the cystic fibrosis population in the U.S., the vast majority of patients were Caucasian. There were 221 patients ≥20 years old, 121 patients ≥13 to <20 years old, and 83 patients ≥6 to <13 years old. There were 239 patients with screening FEV 1 % predicted ≥50%, 156 patients with screening FEV 1 % predicted <50%, and 30 patients with missing FEV 1 % predicted. The primary safety population reflects patients from Study 1, an open-label study comparing TOBI Podhaler with TOBI (tobramycin inhalation solution, USP) over three cycles of 4 weeks on treatment followed by 4 weeks off treatment. Randomization, in a planned 3:2 ratio, resulted in 308 patients treated with TOBI Podhaler and 209 patients treated with TOBI. For both the TOBI Podhaler and TOBI groups, mean exposure to medication for each cycle was 28 to 29 days. The mean age for both arms was between 25 and 26 years old. The mean baseline FEV 1 % predicted for both arms was 53%.

Table

1 displays adverse drug reactions reported by at least 2% of TOBI Podhaler patients in Study 1, inclusive of all cycles (on and off treatment). Adverse drug reactions are listed according to MedDRA system organ class and sorted within system organ class group in descending order of frequency.

Table

1: Adverse Reactions Reported in Study 1 (Occurring in ≥2% of TOBI Podhaler Patients)

Primary System Organ Class Preferred

Term TOBI Podhaler N=308 % TOBI N=209 % Respiratory, thoracic, and mediastinal disorders Cough 48.4

31.1 Lung disorder This includes adverse events of pulmonary or cystic fibrosis exacerbations 33.8

30.1 Productive cough 18.2

19.6 Dyspnea 15.6

12.4 Oropharyngeal pain 14.0

10.5 Dysphonia 13.6

3.8 Hemoptysis 13.0

12.4 Nasal congestion 8.1

7.2 Rales 7.1

6.2 Wheezing 6.8

6.2 Chest discomfort 6.5

2.9 Throat irritation 4.5

1.9 Gastrointestinal disorders Nausea 7.5

9.6 Vomiting 6.2

5.7 Diarrhea 4.2

1.9 Dysgeusia 3.9

0.5 Infections and infestations Upper respiratory tract infection 6.8

8.6 Investigations Pulmonary function test decreased 6.8

8.1 Forced expiratory volume decreased 3.9

1.0 Blood glucose increased 2.9

0.5 Vascular disorders Epistaxis 2.6

1.9 Nervous system disorders Headache 11.4

12.0 General disorders and administration site conditions Pyrexia 15.6

12.4 Musculoskeletal and connective tissue disorders Musculoskeletal chest pain 4.5

4.8 Skin and subcutaneous tissue disorders Rash 2.3

2.4 Adverse drug reactions that occurred in &lt;2% of patients treated with TOBI Podhaler in Study 1 were: bronchospasm (TOBI Podhaler 1.6%, TOBI 0.5%); deafness including deafness unilateral (reported as mild to moderate hearing loss or increased hearing loss) (TOBI Podhaler 1.0%, TOBI 0.5%); and tinnitus (TOBI Podhaler 1.9%, TOBI 2.4%). Discontinuations in Study 1 were higher in the TOBI Podhaler arm compared to TOBI (27% TOBI Podhaler versus 18% TOBI). This was driven primarily by discontinuations due to adverse events (14% TOBI Podhaler versus 8% TOBI). Higher rates of discontinuation were seen in subjects ≥20 years old and those with baseline FEV 1 % predicted &lt;50%. Respiratory related hospitalizations occurred in 24% of the patients in the TOBI Podhaler arm and 22% of the patients in the TOBI arm. There was an increased new usage of antipseudomonal medication in the TOBI Podhaler arm (65% TOBI Podhaler versus 55% TOBI). This included oral antibiotics in 55% of TOBI Podhaler patients and 40% of TOBI patients and intravenous antibiotics in 35% of TOBI Podhaler patients and 33% of TOBI patients. Median time to first antipseudomonal usage was 89 days in the TOBI Podhaler arm and 112 days in the TOBI arm. The supportive safety population reflects patients from two studies: Study 2, a double-blind, placebo-controlled design for the first treatment cycle, followed by all patients receiving TOBI Podhaler (replaced placebo) for two additional cycles, and Study 3, a double-blind, placebo-controlled trial for one treatment cycle only. Placebo in these studies was inhaled powder without the active ingredient, tobramycin. The patient population for these studies was much younger than in Study 1 (mean age 13 years old). Adverse drug reactions reported more frequently by TOBI Podhaler patients in the placebo-controlled cycle (Cycle 1) of Study 2, which included 46 TOBI Podhaler and 49 placebo patients, were: Respiratory, thoracic, and mediastinal disorders Pharyngolaryngeal pain (TOBI Podhaler 10.9%, placebo 0%); dysphonia (TOBI Podhaler 4.3%, placebo 0%) Gastrointestinal disorders Dysgeusia (TOBI Podhaler 6.5%, placebo 2.0%) Adverse drug reactions reported more frequently by TOBI Podhaler patients in Study 3, which included 30 TOBI Podhaler and 32 placebo patients, were: Respiratory, thoracic, and mediastinal disorders Cough (TOBI Podhaler 10%, placebo 0%) Ear and labyrinth disorders Hypoacusis (TOBI Podhaler 10%, placebo 6.3%)

Audiometric Assessment In Study

1, audiology testing was performed in a subset of approximately 25% of TOBI Podhaler (n=78) and TOBI (n=45) patients. Using the criteria for either ear of ≥10 dB loss at two consecutive frequencies, ≥20 dB loss at any frequency, or loss of response at three consecutive frequencies where responses were previously obtained, five TOBI Podhaler patients and three TOBI patients were judged to have ototoxicity, a ratio similar to the planned 3:2 randomization for this study. Audiology testing was also performed in a subset of patients in both Study 2 (n=13 from the TOBI Podhaler group and n=9 from the placebo group) and Study 3 (n=14 from the TOBI Podhaler group and n=11 from the placebo group).

In Study

2, no patients reported hearing complaints but two TOBI Podhaler patients met the criteria for ototoxicity.

In Study

3, three TOBI Podhaler and two placebo patients had reports of ‘hypoacusis.’ One TOBI Podhaler and two placebo patients met the criteria for ototoxicity. In some patients, ototoxicity was transient or may have been related to a conductive defect.

Cough

Cough is a common symptom in cystic fibrosis, reported in 42% of the patients in Study 1 at baseline. Cough was the most frequently reported adverse event in Study 1 and was more common in the TOBI Podhaler arm (48% TOBI Podhaler versus 31 % TOBI). There was a higher rate of cough adverse event reporting during the first week of active treatment with TOBI Podhaler (i.e., the first week of Cycle 1). The time to first cough event in the TOBI Podhaler and TOBI groups were similar thereafter. In some patients, cough resulted in discontinuation of TOBI Podhaler treatment. Sixteen patients (5%) receiving treatment with TOBI Podhaler discontinued study treatment due to cough events compared with 2 (1%) in the TOBI treatment group. Children and adolescents coughed more than adults when treated with TOBI Podhaler, yet the adults were more likely to discontinue: of the 16 patients on TOBI Podhaler in Study 1 who discontinued treatment due to cough events, 14 were ≥20 years of age, one patient was between the ages of 13 and <20, and one was between the ages of 6 and <13. The rates of bronchospasm (as measured by ≥20% decrease in FEV 1 % predicted post-dose) were approximately 5% in both treatment groups, and none of these patients experienced concomitant cough.

In Study

2, cough was the most commonly reported adverse event during the first cycle of treatment (the double blind period of treatment) and occurred more frequently in placebo-treated patients (26.5%) than patients treated with TOBI Podhaler (13%). Similar percentages of patients in both treatment groups reported cough as a baseline symptom.

In Study

3, cough events were reported by three patients in the TOBI Podhaler group (10%) and none in the placebo group (0%).

6.2 Postmarketing Experience The following adverse reactions have been identified during postapproval use of TOBI Podhaler. 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. Respiratory, thoracic, and mediastinal disorders Aphonia, Sputum discolored General disorders and administration site conditions Malaise

AND PRECAUTIONS Bronchospasm: Can occur with inhalation of tobramycin inhalation solution. Treat as medically appropriate, if it occurs. ( 5.1 ) Ototoxicity: Tinnitus and hearing loss have been reported in patients receiving tobramycin inhalation solution. If noted, manage as medically appropriate, including potentially discontinuing tobramycin inhalation solution. ( 5.2 ) Nephrotoxicity: Has been associated with aminoglycosides as a class. If nephrotoxicity develops, manage the patient as medically appropriate, including potentially discontinuing tobramycin inhalation solution. ( 5.3 )

Neuromuscular

Disorders: Aminoglycosides may aggravate muscle weakness because of a potential curare‐like effect on neuromuscular function. If neuromuscular blockade occurs, it may be reversed by the administration of calcium salts but mechanical assistance may be necessary. ( 5.4 ) Embryo-fetal Toxicity: Aminoglycosides can cause fetal harm ( 5.5 , 8.1 )

5.1 Bronchospasm Bronchospasm can occur with inhalation of tobramycin inhalation solution. In clinical studies with tobramycin inhalation solution, changes in FEV 1 measured after the inhaled dose were similar in tobramycin inhalation solution and placebo groups. Bronchospasm that occurs during the use of tobramycin inhalation solution should be treated as medically appropriate.

5.2 Ototoxicity with use of Tobramycin inhalation solution Ototoxicity, manifested as both auditory and vestibular toxicity, has been reported with parenteral aminoglycosides. Transient tinnitus occurred in eight tobramycin inhalation solution treated patients versus no placebo patients in the clinical studies. Tinnitus may be a sentinel symptom of ototoxicity, and therefore the onset of this symptom warrants further clinical investigation. Ototoxicity, as measured by complaints of hearing loss or by audiometric evaluations, did not occur with tobramycin inhalation solution therapy during clinical studies, however in postmarketing experience, patients receiving tobramycin inhalation solution have reported hearing loss. Vestibular toxicity may be manifested by vertigo, ataxia or dizziness. Patients with known or suspected auditory or vestibular dysfunction should be closely monitored when taking tobramycin inhalation solution. Monitoring might include obtaining audiometric evaluations and serum tobramycin levels. If ototoxicity is noted, the patient should be managed as medically appropriate, including potentially discontinuing tobramycin inhalation solution. Risk of Ototoxicity Due to Mitochondrial DNA Variants Cases of ototoxicity with aminoglycosides have been observed in patients with certain variants in the mitochondrially encoded 12S rRNA gene (MT-RNR1), particularly the m.1555A&gt;G variant. Ototoxicity occurred in some patients even when their aminoglycoside serum levels were within the recommended range. Mitochondrial DNA variants are present in less than 1% of the general US population, and the proportion of the variant carriers who may develop ototoxicity as well as the severity of ototoxicity is unknown. In case of known maternal history of ototoxicity due to aminoglycoside use or a known mitochondrial DNA variant in the patient, consider alternative treatments other than aminoglycosides unless the increased risk of permanent hearing loss is outweighed by the severity of infection and lack of safe and effective alternative therapies.

5.3 Nephrotoxicity Nephrotoxicity was not seen during clinical studies with tobramycin inhalation solution but has been associated with aminoglycosides as a class. Patients with known or suspected renal dysfunction or taking concomitant nephrotoxic drugs along with tobramycin inhalation solution should have serum concentrations of tobramycin and laboratory measurements of renal function obtained at the discretion of the treating physician. If nephrotoxicity develops, the patient should be managed as medically appropriate, including potentially discontinuing tobramycin inhalation solution.

5.4 Neuromuscular Disorders Aminoglycosides, including tobramycin, may aggravate muscle weakness because of a potential curare-like effect on neuromuscular function. Neuromuscular blockade, respiratory failure, and prolonged respiratory paralysis may occur more commonly in patients with underlying neuromuscular disorders, such as myasthenia gravis or Parkinson’s disease. Prolonged respiratory paralysis may also occur in patients receiving concomitant neuromuscular blocking agents. If neuromuscular blockade occurs, it may be reversed by the administration of calcium salts but mechanical assistance may be necessary.

5.5 Embryo-fetal Toxicity Aminoglycosides can cause fetal harm when administered to a pregnant woman. Aminoglycosides cross the placenta, and streptomycin has been associated with several reports of total, irreversible, bilateral congenital deafness in pediatric patients exposed in utero. However, systemic absorption of tobramycin following inhaled administration is expected to be minimal <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 ) ]</span>. Patients who use tobramycin inhalation solution during pregnancy, or become pregnant while taking tobramycin inhalation solution should be apprised of the potential hazard to the fetus <span class="opacity-50 text-xs">[see Use in Specific Populations ( 8.1 ) ]</span>.

5.6 Concomitant Use of Systemic Aminoglycosides Patients receiving concomitant tobramycin inhalation solution and parenteral aminoglycoside therapy should be monitored as clinically appropriate for toxicities associated with aminoglycosides as a class. Serum tobramycin levels should be monitored.

5.1 Bronchospasm Bronchospasm can occur with inhalation of tobramycin inhalation solution. In clinical studies with tobramycin inhalation solution, changes in FEV 1 measured after the inhaled dose were similar in tobramycin inhalation solution and placebo groups. Bronchospasm that occurs during the use of tobramycin inhalation solution should be treated as medically appropriate.

5.2 Ototoxicity with use of Tobramycin inhalation solution Ototoxicity, manifested as both auditory and vestibular toxicity, has been reported with parenteral aminoglycosides. Transient tinnitus occurred in eight tobramycin inhalation solution treated patients versus no placebo patients in the clinical studies. Tinnitus may be a sentinel symptom of ototoxicity, and therefore the onset of this symptom warrants further clinical investigation. Ototoxicity, as measured by complaints of hearing loss or by audiometric evaluations, did not occur with tobramycin inhalation solution therapy during clinical studies, however in postmarketing experience, patients receiving tobramycin inhalation solution have reported hearing loss. Vestibular toxicity may be manifested by vertigo, ataxia or dizziness. Patients with known or suspected auditory or vestibular dysfunction should be closely monitored when taking tobramycin inhalation solution. Monitoring might include obtaining audiometric evaluations and serum tobramycin levels. If ototoxicity is noted, the patient should be managed as medically appropriate, including potentially discontinuing tobramycin inhalation solution. Risk of Ototoxicity Due to Mitochondrial DNA Variants Cases of ototoxicity with aminoglycosides have been observed in patients with certain variants in the mitochondrially encoded 12S rRNA gene (MT-RNR1), particularly the m.1555A&gt;G variant. Ototoxicity occurred in some patients even when their aminoglycoside serum levels were within the recommended range. Mitochondrial DNA variants are present in less than 1% of the general US population, and the proportion of the variant carriers who may develop ototoxicity as well as the severity of ototoxicity is unknown. In case of known maternal history of ototoxicity due to aminoglycoside use or a known mitochondrial DNA variant in the patient, consider alternative treatments other than aminoglycosides unless the increased risk of permanent hearing loss is outweighed by the severity of infection and lack of safe and effective alternative therapies.

5.3 Nephrotoxicity Nephrotoxicity was not seen during clinical studies with tobramycin inhalation solution but has been associated with aminoglycosides as a class. Patients with known or suspected renal dysfunction or taking concomitant nephrotoxic drugs along with tobramycin inhalation solution should have serum concentrations of tobramycin and laboratory measurements of renal function obtained at the discretion of the treating physician. If nephrotoxicity develops, the patient should be managed as medically appropriate, including potentially discontinuing tobramycin inhalation solution.

5.4 Neuromuscular Disorders Aminoglycosides, including tobramycin, may aggravate muscle weakness because of a potential curare-like effect on neuromuscular function. Neuromuscular blockade, respiratory failure, and prolonged respiratory paralysis may occur more commonly in patients with underlying neuromuscular disorders, such as myasthenia gravis or Parkinson’s disease. Prolonged respiratory paralysis may also occur in patients receiving concomitant neuromuscular blocking agents. If neuromuscular blockade occurs, it may be reversed by the administration of calcium salts but mechanical assistance may be necessary.

5.5 Embryo-fetal Toxicity Aminoglycosides can cause fetal harm when administered to a pregnant woman. Aminoglycosides cross the placenta, and streptomycin has been associated with several reports of total, irreversible, bilateral congenital deafness in pediatric patients exposed in utero. However, systemic absorption of tobramycin following inhaled administration is expected to be minimal <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 ) ]</span>. Patients who use tobramycin inhalation solution during pregnancy, or become pregnant while taking tobramycin inhalation solution should be apprised of the potential hazard to the fetus <span class="opacity-50 text-xs">[see Use in Specific Populations ( 8.1 ) ]</span>.

5.6 Concomitant Use of Systemic Aminoglycosides Patients receiving concomitant tobramycin inhalation solution and parenteral aminoglycoside therapy should be monitored as clinically appropriate for toxicities associated with aminoglycosides as a class. Serum tobramycin levels should be monitored.

PRECAUTIONS: General Prescribing tobramycin injection in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria. Serum and urine specimens for examination should be collected during therapy, as recommended in the WARNINGS box. Serum calcium, magnesium, and sodium should be monitored. Peak and trough serum levels should be measured periodically during therapy. Prolonged concentrations above 12 mcg/mL should be avoided. Rising trough levels (above 2 mcg/mL) may indicate tissue accumulation. Such accumulation, advanced age, and cumulative dosage may contribute to ototoxicity and nephrotoxicity. It is particularly important to monitor serum levels closely in patients with known renal impairment. A useful guideline would be to perform serum level assays after 2 or 3 doses, so that the dosage could be adjusted if necessary, and at 3- to 4-day intervals during therapy. In the event of changing renal function, more frequent serum levels should be obtained and the dosage or dosage interval adjusted according to the guidelines provided in DOSAGE AND ADMINISTRATION . In order to measure the peak level, a serum sample should be drawn about 30 minutes following intravenous infusion or 1 hour after an intramuscular injection. Trough levels are measured by obtaining serum samples at 8 hours or just prior to the next dose of tobramycin. These suggested time intervals are intended only as guidelines and may vary according to institutional practices. It is important, however, that there be consistency within the individual patient program unless computerized pharmacokinetic dosing programs are available in the institution. These serum-level assays may be especially useful for monitoring the treatment of severely ill patients with changing renal function or of those infected with less susceptible organisms or those receiving maximum dosage. Neuromuscular blockade and respiratory paralysis have been reported in cats receiving very high doses of tobramycin (40 mg/kg). The possibility of prolonged or secondary apnea should be considered if tobramycin is administered to anesthetized patients who are also receiving neuromuscular blocking agents, such as succinylcholine, tubocurarine, or decamethonium, or to patients receiving massive transfusions of citrated blood. If neuromuscular blockade occurs, it may be reversed by the administration of calcium salts. Cross-allergenicity among aminoglycosides has been demonstrated. In patients with extensive burns or cystic fibrosis, altered pharmacokinetics may result in reduced serum concentrations of aminoglycosides. In such patients treated with tobramycin measurement of serum concentration is especially important as a basis for determination of appropriate dosage. Elderly patients may have reduced renal function that may not be evident in the results of routine screening tests, such as BUN or serum creatinine. A creatinine clearance determination may be more useful. Monitoring of renal function during treatment with aminoglycosides is particularly important in such patients. An increased incidence of nephrotoxicity has been reported following concomitant administration of aminoglycoside antibiotics and cephalosporins. Aminoglycosides should be used with caution in patients with muscular disorders, such as myasthenia gravis or parkinsonism, since these drugs may aggravate muscle weakness because of their potential curare-like effect on neuromuscular function. Aminoglycosides may be absorbed in significant quantities from body surfaces after local irrigation or application and may cause neurotoxicity and nephrotoxicity. Aminoglycosides have not been approved for intraocular and/or subconjunctival use. Physicians are advised that macular necrosis has been reported following administration of aminoglycosides, including tobramycin, by these routes. See WARNINGS box regarding concurrent use of potent diuretics and concurrent and sequential use of other neurotoxic or nephrotoxic drugs. The inactivation of tobramycin and other aminoglycosides by ß-lactam-type antibiotics (penicillins or cephalosporins) has been demonstrated in vitro and in patients with severe renal impairment. Such inactivation has not been found in patients with normal renal function who have been given the drugs by separate routes of administration. Therapy with tobramycin may result in overgrowth of nonsusceptible organisms. If overgrowth of nonsusceptible organisms occurs, appropriate therapy should be initiated. Information for Patients Patients should be counseled that antibacterial drugs including tobramycin injection should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When tobramycin injection is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by tobramycin injection or other antibacterial drugs in the future. Diarrhea is a common problem caused by antibiotics which usually ends when the antibiotic is discontinued. Sometimes after starting treatment with antibiotics, patients can develop watery and bloody stools (with or without stomach cramps and fever) even as late as two or more months after having taken the last dose of the antibiotic. If this occurs, patients should contact their physician as soon as possible.

Pregnancy

Category D Aminoglycosides can cause fetal harm when administered to a pregnant woman. Aminoglycoside antibiotics cross the placenta, and there have been several reports of total irreversible bilateral congenital deafness in children whose mothers received streptomycin during pregnancy. Serious side effects to mother, fetus, or newborn have not been reported in the treatment of pregnant women with other aminoglycosides. If tobramycin is used during pregnancy or if the patient becomes pregnant while taking tobramycin, she should be apprised of the potential hazard to the fetus.

Pediatric Use

See INDICATIONS AND USAGE and DOSAGE AND ADMINISTRATION .

Geriatric Use

Elderly patients may be at a higher risk of developing nephrotoxicity and ototoxicity while receiving tobramycin (see WARNINGS , PRECAUTIONS , and OVERDOSAGE ). Other factors that may contribute to nephrotoxicity and ototoxicity are rising trough levels, excessive peak concentrations, dehydration, concomitant use of other neurotoxic or nephrotoxic drugs, and cumulative dose. Peak and trough serum levels should be measured periodically during therapy to assure adequate levels and to avoid potentially toxic levels (see WARNINGS and PRECAUTIONS ). Tobramycin is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Dose reduction is required for patients with impaired renal function (see DOSAGE AND ADMINISTRATION ). Elderly patients may have reduced renal function that may not be evident in the results of routine screening tests, such as BUN or serum creatinine. A creatinine clearance determination may be more useful. Monitoring of renal function during treatment with aminoglycosides is particularly important in the elderly (see PRECAUTIONS ). Each mL of tobramycin (10 mg/mL or 40 mg/mL) contains 0.78 mg (0.034 mEq) of sodium.

General

Prescribing tobramycin injection in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria. Serum and urine specimens for examination should be collected during therapy, as recommended in the WARNINGS box. Serum calcium, magnesium, and sodium should be monitored. Peak and trough serum levels should be measured periodically during therapy. Prolonged concentrations above 12 mcg/mL should be avoided. Rising trough levels (above 2 mcg/mL) may indicate tissue accumulation. Such accumulation, advanced age, and cumulative dosage may contribute to ototoxicity and nephrotoxicity. It is particularly important to monitor serum levels closely in patients with known renal impairment. A useful guideline would be to perform serum level assays after 2 or 3 doses, so that the dosage could be adjusted if necessary, and at 3- to 4-day intervals during therapy. In the event of changing renal function, more frequent serum levels should be obtained and the dosage or dosage interval adjusted according to the guidelines provided in DOSAGE AND ADMINISTRATION . In order to measure the peak level, a serum sample should be drawn about 30 minutes following intravenous infusion or 1 hour after an intramuscular injection. Trough levels are measured by obtaining serum samples at 8 hours or just prior to the next dose of tobramycin. These suggested time intervals are intended only as guidelines and may vary according to institutional practices. It is important, however, that there be consistency within the individual patient program unless computerized pharmacokinetic dosing programs are available in the institution. These serum-level assays may be especially useful for monitoring the treatment of severely ill patients with changing renal function or of those infected with less susceptible organisms or those receiving maximum dosage. Neuromuscular blockade and respiratory paralysis have been reported in cats receiving very high doses of tobramycin (40 mg/kg). The possibility of prolonged or secondary apnea should be considered if tobramycin is administered to anesthetized patients who are also receiving neuromuscular blocking agents, such as succinylcholine, tubocurarine, or decamethonium, or to patients receiving massive transfusions of citrated blood. If neuromuscular blockade occurs, it may be reversed by the administration of calcium salts. Cross-allergenicity among aminoglycosides has been demonstrated. In patients with extensive burns or cystic fibrosis, altered pharmacokinetics may result in reduced serum concentrations of aminoglycosides. In such patients treated with tobramycin measurement of serum concentration is especially important as a basis for determination of appropriate dosage. Elderly patients may have reduced renal function that may not be evident in the results of routine screening tests, such as BUN or serum creatinine. A creatinine clearance determination may be more useful. Monitoring of renal function during treatment with aminoglycosides is particularly important in such patients. An increased incidence of nephrotoxicity has been reported following concomitant administration of aminoglycoside antibiotics and cephalosporins. Aminoglycosides should be used with caution in patients with muscular disorders, such as myasthenia gravis or parkinsonism, since these drugs may aggravate muscle weakness because of their potential curare-like effect on neuromuscular function. Aminoglycosides may be absorbed in significant quantities from body surfaces after local irrigation or application and may cause neurotoxicity and nephrotoxicity. Aminoglycosides have not been approved for intraocular and/or subconjunctival use. Physicians are advised that macular necrosis has been reported following administration of aminoglycosides, including tobramycin, by these routes. See WARNINGS box regarding concurrent use of potent diuretics and concurrent and sequential use of other neurotoxic or nephrotoxic drugs. The inactivation of tobramycin and other aminoglycosides by ß-lactam-type antibiotics (penicillins or cephalosporins) has been demonstrated in vitro and in patients with severe renal impairment. Such inactivation has not been found in patients with normal renal function who have been given the drugs by separate routes of administration. Therapy with tobramycin may result in overgrowth of nonsusceptible organisms. If overgrowth of nonsusceptible organisms occurs, appropriate therapy should be initiated.

Information for Patients Patients should be counseled that antibacterial drugs including tobramycin injection should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When tobramycin injection is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by tobramycin injection or other antibacterial drugs in the future. Diarrhea is a common problem caused by antibiotics which usually ends when the antibiotic is discontinued. Sometimes after starting treatment with antibiotics, patients can develop watery and bloody stools (with or without stomach cramps and fever) even as late as two or more months after having taken the last dose of the antibiotic. If this occurs, patients should contact their physician as soon as possible.

Pregnancy

Category D Aminoglycosides can cause fetal harm when administered to a pregnant woman. Aminoglycoside antibiotics cross the placenta, and there have been several reports of total irreversible bilateral congenital deafness in children whose mothers received streptomycin during pregnancy. Serious side effects to mother, fetus, or newborn have not been reported in the treatment of pregnant women with other aminoglycosides. If tobramycin is used during pregnancy or if the patient becomes pregnant while taking tobramycin, she should be apprised of the potential hazard to the fetus.

Pediatric Use

See INDICATIONS AND USAGE and DOSAGE AND ADMINISTRATION .

Geriatric Use

Elderly patients may be at a higher risk of developing nephrotoxicity and ototoxicity while receiving tobramycin (see WARNINGS , PRECAUTIONS , and OVERDOSAGE ). Other factors that may contribute to nephrotoxicity and ototoxicity are rising trough levels, excessive peak concentrations, dehydration, concomitant use of other neurotoxic or nephrotoxic drugs, and cumulative dose. Peak and trough serum levels should be measured periodically during therapy to assure adequate levels and to avoid potentially toxic levels (see WARNINGS and PRECAUTIONS ). Tobramycin is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Dose reduction is required for patients with impaired renal function (see DOSAGE AND ADMINISTRATION ). Elderly patients may have reduced renal function that may not be evident in the results of routine screening tests, such as BUN or serum creatinine. A creatinine clearance determination may be more useful. Monitoring of renal function during treatment with aminoglycosides is particularly important in the elderly (see PRECAUTIONS ). Each mL of tobramycin (10 mg/mL or 40 mg/mL) contains 0.78 mg (0.034 mEq) of sodium.

INTERACTIONS Concurrent and/or sequential use of tobramycin inhalation solution with other drugs with neurotoxic, nephrotoxic, or ototoxic potential should be avoided ( 7.1 ). Concomitant administration with ethacrynic acid, furosemide, urea, or intravenous mannitol is not recommended due to possible enhancement of aminoglycoside toxicity ( 7.2 ).

7.1 Drugs with Neurotoxic, Nephrotoxic or Ototoxic Potential Concurrent and/or sequential use of tobramycin inhalation solution with other drugs with neurotoxic, nephrotoxic, or ototoxic potential should be avoided.

7.2 Diuretics Some diuretics can enhance aminoglycoside toxicity by altering aminoglycoside concentrations in serum and tissue. Tobramycin inhalation solution should not be administered concomitantly with ethacrynic acid, furosemide, urea, or intravenous mannitol. The interaction between inhaled mannitol and tobramycin inhalation solution has not been evaluated.

7.1 Drugs with Neurotoxic, Nephrotoxic or Ototoxic Potential Concurrent and/or sequential use of tobramycin inhalation solution with other drugs with neurotoxic, nephrotoxic, or ototoxic potential should be avoided.

7.2 Diuretics Some diuretics can enhance aminoglycoside toxicity by altering aminoglycoside concentrations in serum and tissue. Tobramycin inhalation solution should not be administered concomitantly with ethacrynic acid, furosemide, urea, or intravenous mannitol. The interaction between inhaled mannitol and tobramycin inhalation solution has not been evaluated.