Is there an oral equivalent to ceftazidime (Ceftazidime)/avibactam?

No Oral Equivalent to Ceftazidime/Avibactam Currently Exists

There is no oral equivalent to ceftazidime/avibactam currently available. Ceftazidime/avibactam is only available as an intravenous formulation and must be administered via a 2-hour intravenous infusion every 8 hours 1, 2.

Understanding Ceftazidime/Avibactam

Ceftazidime/avibactam is a combination antibiotic consisting of:

• Ceftazidime: A third-generation cephalosporin
• Avibactam: A novel β-lactamase inhibitor that extends ceftazidime's spectrum of activity

This combination has been developed specifically to address multidrug-resistant (MDR) gram-negative infections, particularly those caused by:

• Extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae
• Klebsiella pneumoniae carbapenemase (KPC)-producing organisms
• Certain carbapenem-resistant Enterobacteriaceae (CRE)
• Some resistant Pseudomonas aeruginosa strains 1

Why No Oral Equivalent Exists

The lack of an oral equivalent can be attributed to several factors:

1. Pharmacokinetic challenges: The molecular structure and properties of both ceftazidime and avibactam result in poor oral bioavailability

2. Spectrum of activity: Ceftazidime/avibactam is primarily used for serious, multidrug-resistant infections that typically require intravenous therapy

3. Clinical context: The infections targeted by ceftazidime/avibactam (complicated intra-abdominal infections, complicated urinary tract infections, hospital-acquired pneumonia) generally require initial intravenous therapy 1, 2

Current Approved Indications

Ceftazidime/avibactam is FDA-approved for:

• Complicated intra-abdominal infections (in combination with metronidazole)
• Complicated urinary tract infections, including pyelonephritis
• Hospital-acquired and ventilator-associated pneumonia 2, 3

Alternative Approaches

For patients requiring treatment for resistant gram-negative infections who need oral therapy:

1. Step-down therapy: Initial IV ceftazidime/avibactam followed by an appropriate oral agent based on susceptibility testing

2. Alternative oral options: While not direct equivalents, the following may be considered based on susceptibility testing:

   • Fluoroquinolones (with caution due to resistance concerns) 1
   • Trimethoprim-sulfamethoxazole (if susceptible)
   • Oral fosfomycin (for urinary tract infections only)

Clinical Implications

The lack of an oral equivalent to ceftazidime/avibactam presents challenges in:

1. Transitioning from inpatient to outpatient care: Patients may require:

   • Prolonged hospitalization for IV therapy completion
   • Outpatient parenteral antimicrobial therapy (OPAT)
   • Step-down to a potentially less effective oral agent

2. Resource utilization: Increased healthcare costs and resource utilization due to the need for IV administration

Future Directions

Research is ongoing to develop novel oral agents with activity against resistant gram-negative pathogens. However, at present, there is no oral equivalent to ceftazidime/avibactam, and patients requiring this specific antimicrobial coverage must receive it intravenously 1, 2.