A new drug has been FDA-approved for treating complicated urinary tract infections (UTIs).
What’s special about it? It works in a similar way as others do: combines an antibiotic (cephalosporin) and a beta-lactamase inhibitor (tazobactam).
Side note for the curious ones: the first one (antibiotic) is actually fighting the bacteria, while the second one (beta-lactamase inhibitor) is used to destroy the enzymes the bacteria themselves produce to resist the antibiotics. It is fascinating, if you think about it: Star wars in your bladder. But this is nothing new. Most antibiotics that are used to treat UTI are equipped with a beta-lactamase inhibitor. Zerbaxa (the brand name for the new drug) has performed about 10% better during the trials than Levofloxacin (brand name in US: Levaquin), which has been used to treat complicated UTIs since 2003 and both drugs perform relatively the same in terms of side effects (see the table).
The most common adverse reactions from Zerbaxa are nausea, diarrhea, headaches and fever.
Important Safety Information (from Zerbaxa official website):
- Hypersensitivity: Zerbaxa is contraindicated in patients with known serious hypersensitivity to ceftolozane/tazobactam, piperacillin/tazobactam, or other members of the beta-lactam class. Serious and occasionally fatal hypersensitivity (anaphylactic) reactions have been reported in patients receiving beta-lactam antibacterials. Before initiating therapy with Zerbaxa, make careful inquiry about previous hypersensitivity reactions to cephalosporins, penicillins or other beta-lactams. If an anaphylactic reaction to Zerbaxa occurs, discontinue use and institute appropriate therapy.
- Patients with renal impairment: Decreased efficacy has been observed in patients with baseline CrCl of 30 to ≤50 mL/min. Monitor CrCl at least daily in patients with changing renal function and adjust the dose of Zerbaxa accordingly.
- Clostridium difficile–associated diarrhea (CDAD): ranging from mild diarrhea to fatal colitis, has been reported with nearly all systemic antibacterial agents, including Zerbaxa. Careful medical history is necessary because CDAD has been reported to occur more than two months after the administration of antibacterial agents. If CDAD is confirmed, antibacterial use not directed against C. difficile should be discontinued, if possible.
- Development of drug-resistant bacteria: Prescribing Zerbaxa in the absence of a proven or strongly suspected bacterial infection is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.
Zerbaxa is the first antibiotic approved under the Generating Antibiotic Incentives Now (GAIN) Act to treat Gram-negative bacteria. It will be available as 1g/0.5g single-use vials in 10-count cartons.