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Active Substance: ceftolozane sulfate / tazobactam sodium
Common Name: ceftolozane / tazobactam
ATC Code: J01
Marketing Authorisation Holder: Merck Sharp & Dohme Limited
Active Substance: ceftolozane sulfate / tazobactam sodium
Status: Authorised
Authorisation Date: 2015-09-18
Therapeutic Area: Bacterial Infections
Pharmacotherapeutic Group: Antibacterials for systemic use

Therapeutic Indication

Zerbaxa is indicated for the treatment of the following infections in adults:

  • Complicated intra-abdominal infections;
  • Acute pyelonephritis;
  • Complicated urinary tract infections. 

Consideration should be given to official guidance on the appropriate use of antibacterial agents.

What is Zerbaxa and what is it used for?

Zerbaxa is an antibiotic used to treat adults with complicated (difficult to treat) bacterial infections affecting:

  • tissues and organs within the belly (intra-abdominal infections);
  • the kidneys (pyelonephritis);
  • the urinary tract (structures that carry urine, such as the bladder).

It contains the active substances ceftolozane and tazobactam.

How is Zerbaxa used?

Zerbaxa is available as a powder for preparing a solution for infusion (drip) into a vein and can only be obtained with a prescription. A dose containing 1 g of ceftolozane and 0.5 g of tazobactam is given by infusion over 1 hour every eight hours for 4 to 14 days, depending on the infection being treated and how it responds to the medicine. Prescribers should take into account official guidance on the use of antibiotics. Doses may need to be reduced in patients with reduced kidney function.

How does Zerbaxa work?

The ceftolozane in Zerbaxa is a type of antibiotic called a cephalosporin, which belongs to the wider group called ‘beta-lactams’. It works by interfering with the production of certain molecules that bacteria need to build their protective cell walls. This causes weakness in the bacterial cell walls which then become prone to collapse, ultimately leading to the death of the bacteria.

Zerbaxa also contains tazobactam, a substance which blocks the action of certain enzymes called beta-lactamases. These enzymes enable bacteria to break down beta-lactam antibiotics like ceftolozane, making them resistant to the antibiotic’s action. By blocking the action of these enzymes, tazobactam allows ceftolozane to act against bacteria that would otherwise be resistant.

What benefits of Zerbaxa have been shown in studies?

Zerbaxa has been shown to be at least as effective as other antibiotics in curing infections in two main studies.

One study involved 1,083 patients who mostly had kidney infection or in some cases a complicated urinary-tract infection. Zerbaxa successfully treated the infection in about 85% of the cases where it was given (288 of 340), compared with 75% (266 of 353) of those given another antibiotic called levofloxacin.

The second study involved 993 patients with complicated intra-abdominal infections. Zerbaxa was compared with another antibiotic, meropenem. Both medicines produced a cure in about 94% of patients (353 out of 375 given Zerbaxa and 375 out of 399 given meropenem).

What are the risks associated with Zerbaxa?

The most common side effects with Zerbaxa (which may affect up to 1 in 10 people) are nausea (feeling sick), headache, constipation, diarrhoea and fever, which are generally mild or moderate. For the full list of all side effects reported with Zerbaxa, see the package leaflet.

Zerbaxa must not be used in people who are hypersensitive (allergic) to Zerbaxa or any of its ingredients, or in those who are hypersensitive to other cephalosporin antibiotics or have ever had a severe allergic reaction to another beta-lactam antibiotic.

Why is Zerbaxa approved?

The Agency’s Committee for Medicinal Products for Human Use (CHMP) decided that Zerbaxa’s benefits are greater than its risks and recommended that it be approved for use in the EU. The CHMP considered that Zerbaxa had been shown to be effective at curing infections in the patients studied, but acknowledged that only a limited number of patients with complicated urinary tract infections had been included. The Committee also noted that tazobactam is known not to be active against some classes of beta-lactamase that can cause problems of resistance. Regarding safety, side effects were considered to be typical and expected for an antibiotic of this kind.

What measures are being taken to ensure the safe and effective use of Zerbaxa?

A risk management plan has been developed to ensure that Zerbaxa is used as safely as possible. Based on this plan, safety information has been included in the summary of product characteristics and the package leaflet for Zerbaxa, including the appropriate precautions to be followed by healthcare professionals and patients.

Further information can be found in the summary of the risk management plan.

Other information about Zerbaxa

The European Commission granted a marketing authorisation valid throughout the European Union for Zerbaxa on 18 September 2015.

For more information about treatment with Zerbaxa, read the package leaflet (also part of the EPAR) or contact your doctor or pharmacist.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.