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 piperacillin and tazobactam for injection 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, piperacillin and tazobactam for injection 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 Piperacillin and Tazobactam for Injection Monotherapy Clinical TrialsSystem 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%) |
Pseudomembranous colitis (≤1%) |
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%) |
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 piperacillin and tazobactam for injection 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/tazobactam group and 198 (92.1%) in the imipenem/cilastatin group. Twenty-five (11%) patients in the piperacillin/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 Piperacillin and Tazobactam Injection plus Aminoglycoside Clinical TrialsSystem 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/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 (5.5)].
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 piperacillin and tazobactam for injection 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 piperacillin and tazobactam 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 piperacillin and tazobactam 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 piperacillin and tazobactam group and 73 (27.1%) in the cefotaxime/metronidazole group. Six patients (2.2%) in the piperacillin and tazobactam 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 piperacillin and tazobactam 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 piperacillin and tazobactam and comparator groups, including patients aged 2 months to 9 months treated with piperacillin and tazobactam 90 mg/kg IV every 6 hours and patients older than 9 months and less than 18 years of age treated with piperacillin and tazobactam 112.5 mg/kg IV every 6 hours.