The US Food and Drug Administration (FDA) has approved a new intravenous combination antibacterial product, Avycaz, for the treatment of complicated infections. It contains a third generation cephalosporin beta-lactam antibacterial ceftazidime and a new beta-lactamase inhibitor, avibactam.
The United States will be the first market for Avycaz, with an expected launch date in the second quarter of 2015. An application to the European Medicines Agency is expected to be made in the first quarter of 2015, says a spokesperson for AstraZeneca. It is jointly developing the product with Actavis, which has the distribution rights in North America.
The product is approved for the treatment of two conditions in adults (aged 18 years and over): complicated intra-abdominal infections, in combination with metronidazole, and complicated urinary tract infections, including pyelonephritis, in patients with limited or no alternative treatment options.
The product’s label stresses that to reduce the development of drug-resistant bacteria, Avycaz should only be used to treat infections that are proven or strongly suspected to be caused by susceptible bacteria.
The FDA fast-tracked Avycaz’s approval by designating it a qualified infectious disease product, which is given to antibacterial products that treat serious or life-threatening infections.
The most common cause of resistance to beta-lactam antibiotics, like ceftazidime, is due to the hydrolytic inactivation of the beta-lactam ring by bacterial beta-lactamases. More than 1,400 beta-lactamases have been identified, according to the FDA. Avibactam is a non-beta-lactam beta lactamase inhibitor with little antibacterial activity. Existing beta-lactamase inhibitors include clavulanic acid and tazobactam.
“The recent approval of ceftazidime-avibactam by the FDA adds another agent with activity against multidrug-resistant Gram-negative organisms to the potential armamentarium,” says Paul Wade, consultant pharmacist for infectious diseases at Guy’s & St. Thomas’ NHS Foundation Trust.
“Along with ceftolozane-tazobactam, approved by the FDA in 2014, this widens the range of agents with activity against extended-spectrum beta-lactamase (ESBL)-producing Gram-negative organisms.
“This comes at a time when concerns about rising carbapenem [a class of beta-lactam antibiotics] resistance and usage are at the forefront of national and international antimicrobial stewardship strategies and proposed quality measures in parts of the UK include reductions in carbapenem use in secondary care.”
Wade hopes these agents become available in the EU and UK soon so that “their carbapenem-sparing potential might be fully explored in practice”.
As well as protecting ceftazidime from ESBLs, Actavis says that the addition of avibactam to ceftazidime protects its breakdown by Klebsiella pneumoniae carpenemase and AmcP beta-lactamase producing pathogens.
The recommended dose of the product is 2.5g (2g ceftazidime and 0.5g avibactam) given every eight hours by intravenous infusion over two hours for 5 to 14 days. The most common side effects include vomiting, nausea, constipation and anxiety. The FDA says decreased efficacy, seizures and other neurological events were seen in patients with poor renal function.