Ceftazidime-Avibactam Dosage for Drug-Resistant Gram-Negative Infections
The recommended dosage of ceftazidime-avibactam for treating infections caused by drug-resistant Gram-negative bacteria is 2.5 grams (2 grams ceftazidime plus 0.5 grams avibactam) administered intravenously every 8 hours, infused over 2-3 hours. 1
Standard Dosing Regimen
- Ceftazidime-avibactam 2.5 g IV q8h (2 grams ceftazidime plus 0.5 grams avibactam)
- Administration: Infuse over 2-3 hours
- Standard treatment duration: Varies by infection site (typically 5-14 days)
Indication-Specific Recommendations
Carbapenem-Resistant Enterobacterales (CRE) Bloodstream Infections
- Ceftazidime-avibactam 2.5 g IV q8h infused over 3 hours 1
- Duration: 7-14 days (based on clinical response)
Complicated Urinary Tract Infections (cUTI) due to CRE
- Ceftazidime-avibactam 2.5 g IV q8h 1
- Duration: 5-7 days
Complicated Intra-abdominal Infections (cIAI) due to CRE
- Ceftazidime-avibactam 2.5 g IV q8h in combination with metronidazole 1
- Duration: 5-7 days
Dosage Adjustments
Renal Impairment
Dose adjustment is required for patients with impaired renal function. The standard dosage of 2.5 g IV q8h is appropriate for patients with creatinine clearance (CrCl) >50 mL/min 2. For patients with lower CrCl, dosage should be reduced accordingly.
Clinical Evidence
The efficacy of ceftazidime-avibactam at the 2.5 g dose has been demonstrated in multiple clinical trials:
In the REPRISE trial, ceftazidime-avibactam 2.5 g IV q8h showed clinical cure rates of 91% in patients with ceftazidime-resistant infections, comparable to best available therapy (which was primarily carbapenem-based) 3
Clinical trials have shown high microbiological cure rates (77.4%) for ceftazidime-avibactam in complicated UTIs 4
For infections caused by ceftazidime-non-susceptible pathogens, ceftazidime-avibactam achieved clinical cure rates of 75.5% 4
Important Considerations
Ceftazidime-avibactam has activity against many β-lactamase-producing Gram-negative pathogens, including extended-spectrum β-lactamases (ESBLs), AmpC β-lactamases, and Klebsiella pneumoniae carbapenemase (KPC) 5
Avibactam does not inhibit class B metallo-β-lactamase enzymes (MBLs) such as NDM, VIM, or IMP 1
Development of resistance to ceftazidime-avibactam has been reported, particularly with prior ceftazidime-avibactam exposure 1
For KPC-3 producing organisms, some experts recommend combination therapy with a carbapenem or colistin due to potential resistance development 1
Storage and Administration
- Store at 25°C (77°F); excursions permitted between 15°C and 30°C (59°F and 86°F)
- Protect from light and store in carton until use
- After reconstitution, administer within specified stability timeframe
The 2.5 gram dosage of ceftazidime-avibactam administered every 8 hours has been established through pharmacokinetic/pharmacodynamic modeling to achieve adequate drug concentrations against resistant pathogens with MICs ≤8 mg/L 2.