Ceftazidime-Avibactam Dosage Guidelines
The standard dosage of ceftazidime-avibactam is 2.5 grams (2 grams ceftazidime and 0.5 grams avibactam) administered intravenously every 8 hours as a 2-hour infusion for patients with normal renal function. 1, 2
Standard Dosing
- For complicated urinary tract infections (cUTI) including pyelonephritis: 2.5 g IV q8h as a 2-hour infusion 1
- For complicated intra-abdominal infections (cIAI): 2.5 g IV q8h as a 2-hour infusion, must be used with metronidazole 500 mg IV q6h 1
- For bloodstream infections due to carbapenem-resistant Enterobacterales (CRE): 2.5 g IV q8h infused over 3 hours 1
Dosage Adjustment for Renal Impairment
| Creatinine Clearance (CrCl) | Recommended Dose |
|---|---|
| >50 mL/min | 2.5 g (2 g ceftazidime + 0.5 g avibactam) IV q8h |
| 31-50 mL/min | 1.25 g (1 g ceftazidime + 0.25 g avibactam) IV q8h |
| 16-30 mL/min | 0.94 g (0.75 g ceftazidime + 0.19 g avibactam) IV q12h |
| 6-15 mL/min | 0.94 g (0.75 g ceftazidime + 0.19 g avibactam) IV q24h |
| ≤5 mL/min | 0.94 g (0.75 g ceftazidime + 0.19 g avibactam) IV q48h |
Drug Formulation
Ceftazidime-avibactam is supplied as a white to yellow sterile powder in a single-dose vial containing:
- Ceftazidime 2 grams (equivalent to 2.635 grams of ceftazidime pentahydrate/sodium carbonate powder)
- Avibactam 0.5 grams (equivalent to 0.551 grams of avibactam sodium) 2
Clinical Considerations
- The dosing regimen was developed based on population pharmacokinetic models and probability of target attainment simulations 3
- For CRE infections, ceftazidime-avibactam has shown efficacy with the standard dosing regimen 4
- The fixed-dose combination ratio of 4:1 (ceftazidime:avibactam) was selected based on complementary pharmacokinetic profiles, with both drugs having a half-life of approximately 2 hours 5
- Clinical trials have demonstrated non-inferiority of ceftazidime-avibactam to carbapenems in treating complicated infections, including those caused by ceftazidime-resistant organisms 6
Important Considerations
- Emergence of resistance to ceftazidime-avibactam has been reported in carbapenemase-producing K. pneumoniae, particularly with prior ceftazidime-avibactam exposure 4
- For infections due to KPC-3 producers, some experts suggest considering combination therapy with a carbapenem or colistin, though evidence is limited 4
- Renal function should be monitored during therapy as both components are primarily eliminated through renal clearance 1, 5
The dosing recommendations are based on established guidelines and FDA-approved labeling, with strong evidence supporting the standard 2.5 g q8h dosing regimen for patients with normal renal function.