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 Experience in Adult Patients
Three clinical trials, Trial 1, Trial 2, and Trial 3, underly the EMBLAVEO clinical development program. Trial 1 was a randomized, comparative trial conducted in patients with cIAI and hospital-acquired bacterial pneumonia/ventilator-associated bacterial pneumonia (HABP/VABP) (not an approved indication for EMBLAVEO), while Trials 2 and 3 were smaller, noncomparative trials conducted in patients with cIAI as well as other serious infections caused by gram negative pathogens expressing metallo-beta-lactamases. The safety data from Trial 1 are summarized below.
In Trial 1, EMBLAVEO was evaluated in a comparative clinical trial in patients with cIAI or HABP/VABP; note that EMBLAVEO is not approved for the treatment of HABP/VABP. Trial 1 evaluated 275 patients treated with EMBLAVEO and 137 patients treated with comparator (meropenem +/- colistin); 203 EMBLAVEO-treated patients had a diagnosis of cIAI while 72 EMBLAVEO-treated patients had a diagnosis of HABP/VABP (not an approved indication for EMBLAVEO).
Patients received treatment with EMBLAVEO 2 grams (aztreonam 1.5 grams and avibactam 0.5 grams) or comparator for 5 to 14 days. Patients randomized to EMBLAVEO received a loading dose of aztreonam and avibactam administered by intravenous infusion over 30 minutes immediately followed by an extended loading dose infused over 3 hours, followed by maintenance doses infused over 3 hours every 6 hours based on the participant’s creatinine clearance. Patients with cIAI randomized to EMBLAVEO also received metronidazole 500 mg administered by intravenous infusion over 60 minutes every 8 hours.
The median age of patients in Trial 1 treated with EMBLAVEO was 58 years, ranging between 18 and 87 years old. Patients treated with EMBLAVEO were predominantly male (66%) and White (59%). Approximately 40% (22% of cIAI and 89% of HABP/VABP; not an approved indication) of patients treated with EMBLAVEO had an APACHE II score greater than 10 at baseline.
Death occurred in 6.9% (19/275) of patients who received EMBLAVEO and in 8% (11/137) of patients who received comparator. In patients with cIAI, death occurred in 3.0% (6/203) of patients treated with EMBLAVEO and 2.9% (3/103) in patients treated with comparator. Overall, 3.6% (10/275) of the patients who received EMBLAVEO discontinued treatment due to an adverse reaction, compared with 3.6% (5/137) of patients treated with comparator.
Common adverse reactions occurring in greater than 5% of patients are noted in the table below.
Table 5: Adverse Reactions Occurring in > 5% of Patients in the EMBLAVEO Treatment Arm in Trial 1| Adverse Reactions | EMBLAVEO ± Metronidazole (N=275) n (%) | Meropenem ± Colistin (N=137) n (%) |
| Hepatic adverse reactions* | 40 (14.5) | 16 (11.7) |
| Anemia** | 22 (8.0) | 7 (5.1) |
| Diarrhea | 16 (5.8) | 5 (3.6) |
| Hypokalemia | 16 (5.8) | 4 (2.9) |
| Pyrexia*** | 16 (5.8) | 7 (5.1) |
*Includes AR terms alanine aminotransferase increased, aspartate aminotransferase increased, hepatic function abnormal, hypertransaminasemia, transaminases increased, hepatic enzyme increased, liver injury **Includes anemia, hemoglobin decreased ***Includes pyrexia, hyperpyrexia, hyperthermia, body temperature increased |
Hepatic Adverse Reactions
In Trial 1, 40/275 patients (15%) in the EMBLAVEO arm had hepatic adverse reactions compared to 16/137 (12%) in the comparator arm receiving meropenem with or without colistin. In Trial 1, 10 (3.8%) patients in the EMBLAVEO arm compared to 4 (3.1%) patients in the comparator arm had an ALT elevation greater than or equal to 5 x ULN. No Hy’s Law cases in the EMBLAVEO or comparator arm were seen in Trials 1, 2, and 3. EMBLAVEO was discontinued due to hepatic enzyme elevations in 4 patients in Trials 1, 2, and 3. The transaminase elevations resolved when EMBLAVEO was discontinued.
The following adverse reactions were reported in EMBLAVEO-treated patients at a rate of less than 5% in Trial 1:
- Vascular disorders: Phlebitis, flushing, hypotension
- Skin and subcutaneous tissue disorders: Rash (includes rash and rash macular), dermatitis (includes dermatitis allergic, dermatitis), erythema
- Gastrointestinal Disorders: Vomiting, nausea, abdominal pain (includes abdominal pain, abdominal pain upper, abdominal pain lower), constipation
- Nervous System Disorders: Mental status change (includes mental status changes, delirium, confusional state, and disorientation), dizziness, headache, sleep disorder (includes sleep disorder, insomnia), ageusia, asthenia
- Infectious Diseases: Clostridioides difficile infection (includes Clostridioides difficile infection and Clostridioides difficile colitis)
- Hematologic: Coagulopathy, leukocytosis (includes white blood cell count increased and leukocytosis), thrombocytopenia (includes thrombocytopenia, platelet count decreased); thrombocytosis (includes thrombocytosis, platelet count increased), eosinophilia
- Hypersensitivity: Bronchospasm
Additionally, adverse reactions that have been reported with aztreonam alone that were not reported in EMBLAVEO-treated patients in Trial 1 are listed below:
Hypersensitivity: Anaphylaxis, angioedema
Hematologic: Pancytopenia, neutropenia
Dermatologic: Purpura, erythema multiforme, exfoliative dermatitis, urticaria, petechiae, pruritus, diaphoresis
Cardiovascular: Transient ECG changes (ventricular bigeminy and PVC)
Respiratory: Wheezing, dyspnea, chest pain
Hepatobiliary: Hepatitis, jaundice
Nervous System: Seizure, encephalopathy, vertigo, paresthesia
Musculoskeletal: Muscular aches
Special Senses: Tinnitus, diplopia, numb tongue, sneezing, nasal congestion, halitosis
Other: Vaginal candidiasis, vaginitis, breast tenderness
Body as a Whole: Malaise
Adverse Laboratory Changes reported with aztreonam alone that were not reported in EMBLAVEO-treated patients in Trial 1 are listed below:
Hematologic: Positive Coombs’ test
Renal: Increases in serum creatinine
Trial 2 was a noncomparative study of EMBLAVEO in 34 subjects with cIAI. Trial 3 was a comparative study of EMBLAVEO versus best available therapy in patients with serious infections due to multi-drug resistant gram-negative bacteria producing metallo-beta-lactamases (not an approved indication for EMBLAVEO); 12 patients were treated in the EMBLAVEO arm and 2 patients were treated in the comparator arm. The safety findings for the EMBLAVEO treatment arm in Trials 2 and 3 were similar to those of Trial 1.