Zosyn in Galaxy Containers

1 INDICATIONS AND USAGE ZOSYN is a combination of piperacillin, a penicillin-class antibacterial and tazobactam, a beta-lactamase inhibitor, indicated for the treatment of: • Intra-abdominal infections in adult and pediatric patients 2 months of age and older ( 1.1 ) • Nosocomial pneumonia in adult and pediatric patients 2 months of age and older ( 1.2 ) • Skin and skin structure infections in adults ( 1.3 ) • Female pelvic infections in adults ( 1.4 ) • Community-acquired pneumonia in adults ( 1.5 ) To reduce the development of drug-resistant bacteria and maintain the effectiveness of ZOSYN and other antibacterial drugs, ZOSYN should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria. ( 1.6 ) 1.1 Intra-abdominal Infections ZOSYN is indicated in adults and pediatric patients (2 months of age and older) for the treatment of appendicitis (complicated by rupture or abscess) and peritonitis caused by beta-lactamase producing isolates of Escherichia coli or the following members of the Bacteroides fragilis group: B. fragilis , B. ovatus , B. thetaiotaomicron , or B. vulgatus . 1.2 Nosocomial Pneumonia ZOSYN is indicated in adults and pediatric patients (2 months of age and older) for the treatment of nosocomial pneumonia (moderate to severe) caused by beta-lactamase producing isolates of Staphylococcus aureus and by piperacillin and tazobactam-susceptible Acinetobacter baumannii , Haemophilus influenzae , Klebsiella pneumoniae , and Pseudomonas aeruginosa (Nosocomial pneumonia caused by P. aeruginosa should be treated in combination with an aminoglycoside) [see Dosage and Administration (2) ] . 1.3 Skin and Skin Structure Infections ZOSYN is indicated in adults for the treatment of uncomplicated and complicated skin and skin structure infections, including cellulitis, cutaneous abscesses and ischemic/diabetic foot infections caused by beta-lactamase producing isolates of Staphylococcus aureus . 1.4 Female Pelvic Infections ZOSYN is indicated in adults for the treatment of postpartum endometritis or pelvic inflammatory disease caused by beta-lactamase producing isolates of Escherichia coli . 1.5 Community-acquired Pneumonia ZOSYN is indicated in adults for the treatment of community-acquired pneumonia (moderate severity only) caused by beta-lactamase producing isolates of Haemophilus influenzae . 1.6 Usage To reduce the development of drug-resistant bacteria and maintain the effectiveness of ZOSYN and other antibacterial drugs, ZOSYN should be used only to treat or prevent infections that are proven or strongly suspected to be caused by 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.

2 DOSAGE AND ADMINISTRATION • If a dose of ZOSYN is required that does not equal 2.25 g, 3.375 g, or 4.5 g, ZOSYN injection in GALAXY Containers is not recommended for use and an alternative formulation of ZOSYN should be considered. ( 2.1 ) • Adult Patients With Indications Other Than Nosocomial Pneumonia; The usual daily dosage of ZOSYN for adults is 3.375 g every six hours totaling 13.5 g (12.0 g piperacillin and 1.5 g tazobactam). ( 2.2 ) • Adult Patients with Nosocomial Pneumonia: Initial presumptive treatment of patients with nosocomial pneumonia should start with ZOSYN at a dosage of 4.5 g every six hours plus an aminoglycoside, totaling 18.0 g (16.0 g piperacillin and 2.0 g tazobactam). ( 2.3 ) • Adult Patients with Renal Impairment : Dosage in patients with renal impairment (creatinine clearance ≤40 mL/min) and dialysis patients should be reduced, based on the degree of renal impairment. ( 2.4 ) • Pediatric Patients by Indication and Age: See Table below ( 2.5 ) Recommended Dosage of ZOSYN for Pediatric Patients 2 months of Age and Older, Weighing up to 40 Kg and With Normal Renal Function Age Appendicitis and /or Peritonitis Nosocomial Pneumonia 2 months to 9 months 90 mg/kg (80 mg piperacillin and 10 mg tazobactam) every 8 ( eight ) hours 90 mg/kg (80 mg piperacillin and 10 mg tazobactam) every 6 ( six ) hours Older than 9 months 112.5 mg/kg (100 mg piperacillin and 12.5 mg tazobactam) every 8 ( eight) hours 112.5 mg/kg (100 mg piperacillin and 12.5 mg tazobactam) every 6 ( six) hours • Administer ZOSYN by intravenous infusion over 30 minutes to both adult and pediatric patients ( 2.2 , 2.3 , 2.4 , 2.5 ). • ZOSYN and aminoglycosides should be reconstituted, diluted, and administered separately. Co-administration via Y-site can be done under certain conditions. ( 2.7 ) See the full prescribing information for the preparation and administration instructions for ZOSYN Injection in GALAXY Containers. 2.1 Important Administration Instructions If a dose of ZOSYN is required that does not equal 2.25 g, 3.375 g, or 4.5 g, ZOSYN injection in GALAXY Containers is not recommended for use and an alternative formulation of ZOSYN should be considered. 2.2 Dosage in Adult Patients With Indications Other Than Nosocomial Pneumonia The usual total daily dosage of ZOSYN for adult patients with indications other than nosocomial pneumonia is 3.375 g every six hours [totaling 13.5 g (12.0 g piperacillin and 1.5 g tazobactam)], to be administered by intravenous infusion over 30 minutes. The usual duration of ZOSYN treatment is from 7 to 10 days. 2.3 Dosage in Adult Patients With Nosocomial Pneumonia Initial presumptive treatment of adult patients with nosocomial pneumonia should start with ZOSYN at a dosage of 4.5 g every six hours plus an aminoglycoside, [totaling 18.0 g (16.0 g piperacillin and 2.0 g tazobactam)], administered by intravenous infusion over 30 minutes. The recommended duration of ZOSYN treatment for nosocomial pneumonia is 7 to 14 days. Treatment with the aminoglycoside should be continued in patients from whom P. aeruginosa is isolated. 2.4 Dosage in Adult Patients With Renal Impairment In adult patients with renal impairment (creatinine clearance ≤ 40 mL/min) and dialysis patients (hemodialysis and CAPD), the intravenous dose of ZOSYN should be reduced based on the degree of renal impairment. The recommended daily dosage of ZOSYN for patients with renal impairment administered by intravenous infusion over 30 minutes is described in Table 1. Table 1: Recommended Dosage of ZOSYN in Patients with Normal Renal Function and Renal Impairment (As total grams piperacillin and tazobactam) Administer ZOSYN by intravenous infusion over 30 minutes. Creatinine clearance, mL/min All Indications (except nosocomial pneumonia) Nosocomial Pneumonia Greater than 40 mL/min 3.375 every 6 hours 4.5 every 6 hours 20 to 40 mL/min Creatinine clearance for patients not receiving hemodialysis 2.25 every 6 hours 3.375 every 6 hours Less than 20 mL/min 2.25 every 8 hours 2.25 every 6 hours Hemodialysis 0.75 g (0.67 g piperacillin and 0.08 g tazobactam) should be administered following each hemodialysis session on hemodialysis days 2.25 every 12 hours 2.25 every 8 hours CAPD 2.25 every 12 hours 2.25 every 8 hours For patients on hemodialysis, the maximum dose is 2.25 g every twelve hours for all indications other than nosocomial pneumonia and 2.25 g every eight hours for nosocomial pneumonia. Since hemodialysis removes 30% to 40% of the administered dose, an additional dose of 0.75 g ZOSYN (0.67 g piperacillin and 0.08 g tazobactam) should be administered following each dialysis period on hemodialysis days. No additional dosage of ZOSYN is necessary for CAPD patients. 2.5 Dosage in Pediatric Patients With Appendicitis/Peritonitis or Nosocomial Pneumonia The recommended dosage for pediatric patients with appendicitis and/or peritonitis or nosocomial pneumonia aged 2 months of age and older, weighing up to 40 kg, and with normal renal function, is described in Table 2 [see Use in Specific Populations (8.4) and Clinical Pharmacology (12.3) ] . Table 2: Recommended Dosage of ZOSYN in Pediatric Patients 2 Months of Age and Older, Weighing Up to 40 kg, and With Normal Renal Function Administer ZOSYN by intravenous infusion over 30 minutes If a dose of ZOSYN is required that does not equal 2.25 g, 3.375 g, or 4.5 g, ZOSYN injection in GALAXY Containers is not recommended for use and an alternative formulation of ZOSYN should be considered [see Use in Specific Populations (8.4) ] . Age Appendicitis and/or Peritonitis Nosocomial Pneumonia 2 months to 9 months 90 mg/kg (80 mg piperacillin and 10 mg tazobactam) every 8 ( eight ) hours 90 mg/kg (80 mg piperacillin and 10 mg tazobactam) every 6 ( six ) hours Older than 9 months of age 112.5 mg/kg (100 mg piperacillin and 12.5 mg tazobactam) every 8 ( eight ) hours 112.5 mg/kg (100 mg piperacillin and 12.5 mg tazobactam) every 6 ( six ) hours Pediatric patients weighing over 40 kg and with normal renal function should receive the adult dose [see Dosage and Administration (2.2 , 2.3) ] . Dosage of ZOSYN in pediatric patients with renal impairment has not been determined. 2.6 Directions for Use of ZOSYN Injection Important Administration Instructions for ZOSYN Injection in GALAXY Containers Administer ZOSYN Injection in GALAXY Containers using sterile equipment, after thawing to room temperature. ZOSYN containing EDTA is compatible for co-administration via a Y-site intravenous tube with Lactated Ringer's injection, USP. Do NOT add supplementary medication. Unused portions of ZOSYN Injection should be discarded. Do NOT use plastic containers in series connections. Such use could result in air embolism due to residual air being drawn from the primary container before administration of the fluid from the secondary container is complete. Handle frozen product containers with care. Product containers may be fragile in the frozen state. Thawing of Plastic Container Thaw frozen container at room temperature 20°C to 25°C [68°F to 77°F] or under refrigeration (2°C to 8°C [36°F to 46°F]). Do not force thaw by immersion in water baths or by microwave irradiation. Check for minute leaks by squeezing container firmly. If leaks are detected, discard solution as sterility may be impaired. The container should be visually inspected. Components of the solution may precipitate in the frozen state and will dissolve upon reaching room temperature with little or no agitation. Potency is not affected. Agitate after solution has reached room temperature. If after visual inspection, the solution remains cloudy or if an insoluble precipitate is noted or if any seals or outlet ports are not intact, the container should be discarded. Administration Instructions for ZOSYN Injection in GALAXY Containers to Adult Patients Administer by infusion over a period of at least 30 minutes. During the infusion it is desirable to discontinue the primary infusion solution. Administration Instruction for ZOSYN Injection in GALAXY Containers to Pediatric Patients Weighing up to 40 kg If a dose of ZOSYN is required that does not equal 2.25 g, 3.375 g, or 4.5 g, ZOSYN injection in GALAXY Containers is not recommended for use and an alternative formulation of ZOSYN should be considered. Storage of ZOSYN Injection Store in a freezer capable of maintaining a temperature of -20°C (-4°F). For GALAXY Containers, the thawed solution is stable for 14 days under refrigeration (2°C to 8°C [36°F to 46°F]) or 24 hours at room temperature 20°C to 25°C [68°F to 77°F]. Do not refreeze thawed ZOSYN Injection. 2.7 Compatibility With Aminoglycosides Due to the in vitro inactivation of aminoglycosides by piperacillin, ZOSYN and aminoglycosides are recommended for separate administration. ZOSYN and aminoglycosides should be reconstituted, diluted, and administered separately when concomitant therapy with aminoglycosides is indicated [see Drug Interactions (7.1) ] . In circumstances where co-administration via Y-site is necessary, ZOSYN formulations containing EDTA are compatible for simultaneous co-administration via Y-site infusion only with the following aminoglycosides under the following conditions: Table 3: Compatibility with Aminoglycosides Aminoglycoside ZOSYN Dose (grams) Aminoglycoside Concentration Range The concentration ranges in Table 3 are based on administration of the aminoglycoside in divided doses (10–15 mg/kg/day in two daily doses for amikacin and 3–5 mg/kg/day in three daily doses for gentamicin). Administration of amikacin or gentamicin in a single daily dose or in doses exceeding those stated above via Y-site with ZOSYN containing EDTA has not been evaluated. See package insert for each aminoglycoside for complete Dosage and Administration instructions. (mg/mL) Acceptable Diluents Amikacin 2.25 3.375 4.5 1.75 – 7.5 0.9% sodium chloride or 5% dextrose Gentamicin 2.25 3.375 ZOSYN 3.375 g per 50 mL GALAXY Containers are NOT compatible with gentamicin for co-administration via a Y-site due to the higher concentrations of piperacillin and tazobactam. 4.5 0.7 – 3.32 0.9% sodium chloride or 5% dextrose Only the concentration and diluents for amikacin or gentamicin with the dosages of ZOSYN listed above have been established as compatible for co-administration via Y-site infusion. Simultaneous co-administration via Y-site infusion in any manner other than listed above may result in inactivation of the aminoglycoside by ZOSYN. ZOSYN is not compatible with tobramycin for simultaneous co-administration via Y-site infusion. Compatibility of ZOSYN with other aminoglycosides has not been established. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

4 CONTRAINDICATIONS ZOSYN is contraindicated in patients with a history of allergic reactions to any of the penicillins, cephalosporins, or beta-lactamase inhibitors. Patients with a history of allergic reactions to any of the penicillins, cephalosporins, or beta-lactamase inhibitors. ( 4 )

5 WARNINGS AND PRECAUTIONS • Serious hypersensitivity reactions (anaphylactic/anaphylactoid) reactions have been reported in patients receiving ZOSYN. Discontinue ZOSYN if a reaction occurs. ( 5.1 ) • ZOSYN may cause severe cutaneous adverse reactions, such as Stevens-Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms, and acute generalized exanthematous pustulosis. Discontinue ZOSYN for progressive rashes. ( 5.2 ) • Hemophagocytic lymphohistiocytosis (HLH) has been reported with the use of ZOSYN. If HLH is suspected, discontinue ZOSYN immediately. ( 5.3 ) • Hematological effects (including bleeding, leukopenia and neutropenia) have occurred. Monitor hematologic tests during prolonged therapy. ( 5.4 ) • As with other penicillins, ZOSYN may cause neuromuscular excitability or seizures. Patients receiving higher doses, especially in the presence of renal impairment may be at greater risk. Closely monitor patients with renal impairment or seizure disorders for signs and symptoms of neuromuscular excitability or seizures. ( 5.5 ) • Nephrotoxicity in critically ill patients has been observed; the use of ZOSYN was found to be an independent risk factor for renal failure and was associated with delayed recovery of renal function as compared to other beta-lactam antibacterial drugs in a randomized, multicenter, controlled trial in critically ill patients. Based on this study, alternative treatment options should be considered in the critically ill population. If alternative treatment options are inadequate or unavailable, monitor renal function during treatment with ZOSYN. ( 5.6 ) • Clostridioides difficile- associated diarrhea: evaluate patients if diarrhea occurs. ( 5.8 ) 5.1 Hypersensitivity Adverse Reactions Serious and occasionally fatal hypersensitivity (anaphylactic/anaphylactoid) reactions (including shock) have been reported in patients receiving therapy with ZOSYN. These reactions are more likely to occur in individuals with a history of penicillin, cephalosporin, or carbapenem hypersensitivity or a history of sensitivity to multiple allergens. Before initiating therapy with ZOSYN, careful inquiry should be made concerning previous hypersensitivity reactions. If an allergic reaction occurs, ZOSYN should be discontinued and appropriate therapy instituted. 5.2 Severe Cutaneous Adverse Reactions ZOSYN may cause severe cutaneous adverse reactions, such as Stevens-Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms, and acute generalized exanthematous pustulosis. If patients develop a skin rash they should be monitored closely and ZOSYN discontinued if lesions progress. 5.3 Hemophagocytic Lymphohistiocytosis Cases of hemophagocytic lymphohistiocytosis (HLH) have been reported in pediatric and adult patients treated with ZOSYN. Signs and symptoms of HLH may include fever, rash, lymphadenopathy, hepatosplenomegaly and cytopenia. If HLH is suspected, discontinue ZOSYN immediately and institute appropriate management. 5.4 Hematologic Adverse Reactions Bleeding manifestations have occurred in some patients receiving beta-lactam drugs, including piperacillin. These reactions have sometimes been associated with abnormalities of coagulation tests such as clotting time, platelet aggregation and prothrombin time, and are more likely to occur in patients with renal failure. If bleeding manifestations occur, ZOSYN should be discontinued and appropriate therapy instituted. The leukopenia/neutropenia associated with ZOSYN administration appears to be reversible and most frequently associated with prolonged administration. Periodic assessment of hematopoietic function should be performed, especially with prolonged therapy, i.e., ≥ 21 days [see Adverse Reactions (6.1) ] . 5.5 Central Nervous System Adverse Reactions As with other penicillins, ZOSYN may cause neuromuscular excitability or seizures. Patients receiving higher doses, especially patients with renal impairment may be at greater risk for central nervous system adverse reactions. Closely monitor patients with renal impairment or seizure disorders for signs and symptoms of neuromuscular excitability or seizures [see Adverse Reactions (6.2) ] . 5.6 Nephrotoxicity in Critically Ill Patients The use of ZOSYN was found to be an independent risk factor for renal failure and was associated with delayed recovery of renal function as compared to other beta-lactam antibacterial drugs in a randomized, multicenter, controlled trial in critically ill patients [see Adverse Reactions (6.1) ] . Based on this study, alternative treatment options should be considered in the critically ill population. If alternative treatment options are inadequate or unavailable, monitor renal function during treatment with ZOSYN [see Dosage and Administration (2.4) ] . Combined use of piperacillin and tazobactam and vancomycin may be associated with an increased incidence of acute kidney injury [see Drug Interactions (7.3) ] . 5.7 Electrolyte Effects ZOSYN contains a total of 2.84 mEq (65 mg) of Na + (sodium) per gram of piperacillin in the combination product. This should be considered when treating patients requiring restricted salt intake. Periodic electrolyte determinations should be performed in patients with low potassium reserves, and the possibility of hypokalemia should be kept in mind with patients who have potentially low potassium reserves and who are receiving cytotoxic therapy or diuretics. 5.8 Clostridioides difficile- Associated Diarrhea Clostridioides difficile -associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including ZOSYN, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile . C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibacterial drug use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibacterial drug use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibacterial treatment of C. difficile , and surgical evaluation should be instituted as clinically indicated. 5.9 Development of Drug-Resistant Bacteria Prescribing ZOSYN 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 development of drug-resistant bacteria.

7 DRUG INTERACTIONS • ZOSYN administration can significantly reduce tobramycin concentrations in hemodialysis patients. Monitor tobramycin concentrations in these patients. ( 7.1 ) • Probenecid prolongs the half-lives of piperacillin and tazobactam and should not be co-administered with ZOSYN unless the benefit outweighs the risk. ( 7.2 ) • Co-administration of ZOSYN with vancomycin may increase the incidence of acute kidney injury. Monitor kidney function in patients receiving ZOSYN and vancomycin. ( 7.3 ) • Monitor coagulation parameters in patients receiving ZOSYN and heparin or oral anticoagulants. ( 7.4 ) • ZOSYN may prolong the neuromuscular blockade of vecuronium and other non-depolarizing neuromuscular blockers. Monitor for adverse reactions related to neuromuscular blockade. ( 7.5 ) 7.1 Aminoglycosides Piperacillin may inactivate aminoglycosides by converting them to microbiologically inert amides. In vivo inactivation : When aminoglycosides are administered in conjunction with piperacillin to patients with end-stage renal disease requiring hemodialysis, the concentrations of the aminoglycosides (especially tobramycin) may be significantly reduced and should be monitored. Sequential administration of ZOSYN and tobramycin to patients with either normal renal function or mild to moderate renal impairment has been shown to modestly decrease serum concentrations of tobramycin but no dosage adjustment is considered necessary. In vitro inactivation : Due to the in vitro inactivation of aminoglycosides by piperacillin, ZOSYN and aminoglycosides are recommended for separate administration. ZOSYN and aminoglycosides should be reconstituted, diluted, and administered separately when concomitant therapy with aminoglycosides is indicated. ZOSYN, which contains EDTA, is compatible with amikacin and gentamicin for simultaneous Y-site infusion in certain diluents and at specific concentrations. ZOSYN is not compatible with tobramycin for simultaneous Y-site infusion [see Dosage and Administration (2.7) ] . 7.2 Probenecid Probenecid administered concomitantly with ZOSYN prolongs the half-life of piperacillin by 21% and that of tazobactam by 71% because probenecid inhibits tubular renal secretion of both piperacillin and tazobactam. Probenecid should not be co-administered with ZOSYN unless the benefit outweighs the risk. 7.3 Vancomycin Studies have detected an increased incidence of acute kidney injury in patients concomitantly administered piperacillin and tazobactam and vancomycin as compared to vancomycin alone [see Warnings and Precautions (5.6) ] . Monitor kidney function in patients concomitantly administered with piperacillin and tazobactam and vancomycin. No pharmacokinetic interactions have been noted between piperacillin and tazobactam and vancomycin. 7.4 Anticoagulants Coagulation parameters should be tested more frequently and monitored regularly during simultaneous administration of high doses of heparin, oral anticoagulants, or other drugs that may affect the blood coagulation system or the thrombocyte function [see Warnings and Precautions (5.4) ] . 7.5 Vecuronium Piperacillin when used concomitantly with vecuronium has been implicated in the prolongation of the neuromuscular blockade of vecuronium. ZOSYN could produce the same phenomenon if given along with vecuronium. Due to their similar mechanism of action, it is expected that the neuromuscular blockade produced by any of the non-depolarizing neuromuscular blockers could be prolonged in the presence of piperacillin. Monitor for adverse reactions related to neuromuscular blockade (see package insert for vecuronium bromide). 7.6 Methotrexate Limited data suggests that co-administration of methotrexate and piperacillin may reduce the clearance of methotrexate due to competition for renal secretion. The impact of tazobactam on the elimination of methotrexate has not been evaluated. If concurrent therapy is necessary, serum concentrations of methotrexate as well as the signs and symptoms of methotrexate toxicity should be frequently monitored. 7.7 Effects on Laboratory Tests There have been reports of positive test results using the Bio-Rad Laboratories Platelia Aspergillus EIA test in patients receiving piperacillin and tazobactam injection who were subsequently found to be free of Aspergillus infection. Cross-reactions with non-Aspergillus polysaccharides and polyfuranoses with the Bio-Rad Laboratories Platelia Aspergillus EIA test have been reported. Therefore, positive test results in patients receiving piperacillin and tazobactam should be interpreted cautiously and confirmed by other diagnostic methods. As with other penicillins, the administration of ZOSYN may result in a false-positive reaction for glucose in the urine using a copper-reduction method (CLINITEST ® ). It is recommended that glucose tests based on enzymatic glucose oxidase reactions be used.

6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: • Hypersensitivity Adverse Reactions [see Warnings and Precautions (5.1) ] • Severe Cutaneous Adverse Reactions [see Warnings and Precautions (5.2) ] • Hemophagocytic Lymphohistiocytosis [see Warnings and Precautions (5.3) ] • Hematologic Adverse Reactions [see Warnings and Precautions (5.4) ] • Central Nervous System Adverse Reactions [see Warnings and Precautions (5.5) ] • Nephrotoxicity in Critically Ill Patients [see Warnings and Precautions (5.6) ] • Clostridioides difficile- Associated Diarrhea [see Warnings and Precautions (5.8) ] The most common adverse reactions (incidence >5%) are diarrhea, constipation, nausea, headache, and insomnia. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc. at 1-800-438-1985 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. Clinical Trials in Adult Patients During the initial clinical investigations, 2621 patients worldwide were treated with ZOSYN in phase 3 trials. In the key North American monotherapy clinical trials (n=830 patients), 90% of the adverse events reported were mild to moderate in severity and transient in nature. However, in 3.2% of the patients treated worldwide, ZOSYN was discontinued because of adverse events primarily involving the skin (1.3%), including rash and pruritus; the gastrointestinal system (0.9%), including diarrhea, nausea, and vomiting; and allergic reactions (0.5%). Table 4: Adverse Reactions from ZOSYN Monotherapy Clinical Trials System Organ Class Adverse Reaction Gastrointestinal disorders Diarrhea (11.3%) Constipation (7.7%) Nausea (6.9%) Vomiting (3.3%) Dyspepsia (3.3%) Abdominal pain (1.3%) General disorders and administration site conditions Fever (2.4%) Injection site reaction (≤1%) Rigors (≤1%) Immune system disorders Anaphylaxis (≤1%) Infections and infestations Candidiasis (1.6%) Pseudomembranous colitis (≤1%) Metabolism and nutrition disorders Hypoglycemia (≤1%) Musculoskeletal and connective tissue disorders Myalgia (≤1%) Arthralgia (≤1%) Nervous system disorders Headache (7.7%) Psychiatric disorders Insomnia (6.6%) Skin and subcutaneous tissue disorders Rash (4.2%, including maculopapular, bullous, and urticarial) Pruritus (3.1%) Purpura (≤1%) Vascular disorders Phlebitis (1.3%) Thrombophlebitis (≤1%) Hypotension (≤1%) Flushing (≤1%) Respiratory, thoracic and mediastinal disorders Epistaxis (≤1%) Nosocomial Pneumonia Trials Two trials of nosocomial lower respiratory tract infections were conducted. In one study, 222 patients were treated with ZOSYN in a dosing regimen of 4.5 g every 6 hours in combination with an aminoglycoside and 215 patients were treated with imipenem/cilastatin (500 mg/500 mg every 6 hours) in combination with an aminoglycoside. In this trial, treatment-emergent adverse events were reported by 402 patients, 204 (91.9%) in the piperacillin and tazobactam group and 198 (92.1%) in the imipenem/cilastatin group. Twenty-five (11.0%) patients in the piperacillin and tazobactam group and 14 (6.5%) in the imipenem/cilastatin group (p > 0.05) discontinued treatment due to an adverse event. The second trial used a dosing regimen of 3.375 g given every 4 hours with an aminoglycoside. Table 5: Adverse Reactions from ZOSYN Plus Aminoglycoside Clinical Trials For adverse drug reactions that appeared in both studies the higher frequency is presented. System Organ Class Adverse Reaction Blood and lymphatic system disorders Thrombocythemia (1.4%) Anemia (≤1%) Thrombocytopenia (≤1%) Eosinophilia (≤1%) Gastrointestinal disorders Diarrhea (20%) Constipation (8.4%) Nausea (5.8%) Vomiting (2.7%) Dyspepsia (1.9%) Abdominal pain (1.8%) Stomatitis (≤1%) General disorders and administration site conditions Fever (3.2%) Injection site reaction (≤1%) Infections and infestations Oral candidiasis (3.9%) Candidiasis (1.8%) Investigations BUN increased (1.8%) Blood creatinine increased (1.8%) Liver function test abnormal (1.4%) Alkaline phosphatase increased (≤1%) Aspartate aminotransferase increased (≤1%) Alanine aminotransferase increased (≤1%) Metabolism and nutrition disorders Hypoglycemia (≤1%) Hypokalemia (≤1%) Nervous system disorders Headache (4.5%) Psychiatric disorders Insomnia (4.5%) Renal and urinary disorders Renal failure (≤1%) Skin and subcutaneous tissue disorders Rash (3.9%) Pruritus (3.2%) Vascular disorders Thrombophlebitis (1.3%) Hypotension (1.3%) Other Trials: Nephrotoxicity In a randomized, multicenter, controlled trial in 1200 adult critically ill patients, piperacillin and tazobactam was found to be a risk factor for renal failure (odds ratio 1.7, 95% CI 1.18 to 2.43), and associated with delayed recovery of renal function as compared to other beta-lactam antibacterial drugs 1 [see Warnings and Precautions (5.6) ] . Adverse Laboratory Changes (Seen During Clinical Trials) Of the trials reported, including that of nosocomial lower respiratory tract infections in which a higher dose of ZOSYN was used in combination with an aminoglycoside, changes in laboratory parameters include: Hematologic —decreases in hemoglobin and hematocrit, thrombocytopenia, increases in platelet count, eosinophilia, leukopenia, neutropenia. These patients were withdrawn from therapy; some had accompanying systemic symptoms (e.g., fever, rigors, chills) Coagulation —positive direct Coombs' test, prolonged prothrombin time, prolonged partial thromboplastin time Hepatic —transient elevations of AST (SGOT), ALT (SGPT), alkaline phosphatase, bilirubin Renal —increases in serum creatinine, blood urea nitrogen Additional laboratory events include abnormalities in electrolytes (i.e., increases and decreases in sodium, potassium, and calcium), hyperglycemia, decreases in total protein or albumin, blood glucose decreased, gamma-glutamyltransferase increased, hypokalemia, and bleeding time prolonged. Clinical Trials in Pediatric Patients Clinical studies of ZOSYN in pediatric patients suggest a similar safety profile to that seen in adults. In a prospective, randomized, comparative, open-label clinical trial of pediatric patients, 2 to 12 years of age, with intra-abdominal infections (including appendicitis and/or peritonitis), 273 patients were treated with ZOSYN 112.5 mg/kg given IV every 8 hours and 269 patients were treated with cefotaxime (50 mg/kg) plus metronidazole (7.5 mg/kg) every 8 hours. In this trial, treatment-emergent adverse events were reported by 146 patients, 73 (26.7%) in the ZOSYN group and 73 (27.1%) in the cefotaxime/metronidazole group. Six patients (2.2%) in the ZOSYN group and 5 patients (1.9%) in the cefotaxime/metronidazole group discontinued due to an adverse event. In a retrospective, cohort study, 140 pediatric patients 2 months to less than 18 years of age with nosocomial pneumonia were treated with ZOSYN and 267 patients were treated with comparators (which included ticarcillin-clavulanate, carbapenems, ceftazidime, cefepime, or ciprofloxacin). The rates of serious adverse reactions were generally similar between the ZOSYN and comparator groups, including patients aged 2 months to 9 months treated with ZOSYN 90 mg/kg IV every 6 hours and patients older than 9 months and less than 18 years of age treated with ZOSYN 112.5 mg/kg IV every 6 hours. 6.2 Postmarketing Experience In addition to the adverse drug reactions identified in clinical trials in Table 4 and Table 5, the following adverse reactions have been identified during post-approval use of ZOSYN. 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. Hepatobiliary —hepatitis, jaundice Hematologic —hemolytic anemia, agranulocytosis, pancytopenia Immune —hypersensitivity reactions, anaphylactic/anaphylactoid reactions (including shock), hemophagocytic lymphohistiocytosis (HLH) Renal —interstitial nephritis Nervous system disorders —seizures Psychiatric disorders— delirium Respiratory —eosinophilic pneumonia Skin and Appendages —erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms, (DRESS), acute generalized exanthematous pustulosis (AGEP), dermatitis exfoliative Postmarketing experience with ZOSYN in pediatric patients suggests a similar safety profile to that seen in adults. 6.3 Additional Experience with Piperacillin The following adverse reaction has also been reported for piperacillin for injection: Skeletal —prolonged neuromuscular blockade [see Drug Interactions (7.5) ].

8.1 Pregnancy Risk Summary Piperacillin and tazobactam cross the placenta in humans. However, there are insufficient data with piperacillin and/or tazobactam in pregnant women to inform a drug-associated risk for major birth defects and miscarriage. No fetal structural abnormalities were observed in rats or mice when piperacillin and tazobactam was administered intravenously during organogenesis at doses 1 to 2 times and 2 to 3 times the human dose of piperacillin and tazobactam, respectively, based on body-surface area (mg/m 2 ). However, fetotoxicity in the presence of maternal toxicity was observed in developmental toxicity and peri/postnatal studies conducted in rats (intraperitoneal administration prior to mating and throughout gestation or from gestation day 17 through lactation day 21) at doses less than the maximum recommended human daily dose based on body-surface area (mg/m 2 ) (see Data ) . The background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2–4% and 15–20%, respectively. Data Animal Data In embryo-fetal development studies in mice and rats, pregnant animals received intravenous doses of piperacillin and tazobactam up to 3000/750 mg/kg/day during the period of organogenesis. There was no evidence of teratogenicity up to the highest dose evaluated, which is 1 to 2 times and 2 to 3 times the human dose of piperacillin and tazobactam, in mice and rats respectively, based on body-surface area (mg/m 2 ). Fetal body weights were reduced in rats at maternally toxic doses at or above 500/62.5 mg/kg/day, minimally representing 0.4 times the human dose of both piperacillin and tazobactam based on body-surface area (mg/m 2 ). A fertility and general reproduction study in rats using intraperitoneal administration of tazobactam or the combination piperacillin and tazobactam prior to mating and through the end of gestation, reported a decrease in litter size in the presence of maternal toxicity at 640 mg/kg/day tazobactam (4 times the human dose of tazobactam based on body-surface area), and decreased litter size and an increase in fetuses with ossification delays and variations of ribs, concurrent with maternal toxicity at ≥640/160 mg/kg/day piperacillin and tazobactam (0.5 times and 1 times the human dose of piperacillin and tazobactam, respectively, based on body-surface area). Peri/postnatal development in rats was impaired with reduced pup weights, increased stillbirths, and increased pup mortality concurrent with maternal toxicity after intraperitoneal administration of tazobactam alone at doses ≥320 mg/kg/day (2 times the human dose based on body surface area) or of the combination piperacillin and tazobactam at doses ≥640/160 mg/kg/day (0.5 times and 1 times the human dose of piperacillin and tazobactam, respectively, based on body-surface area) from gestation day 17 through lactation day 21.