New injectable antibiotic welcomed with open arms

That's why the recent approval of Doribax (doripenem for injection, Johnson & Johnson), a broad-spectrum antibiotic, for the treatment of complicated intra-abdominal and complicated urinary tract infections is being met with open arms. Doripenem is a member of the carbapenem family of antibiotics. It exhibits bactericidal activity by inhibiting bacterial cell wall biosynthesis and has activity against gram-positive and gram-negative pathogens. It has shown effectiveness against Escherichia coli, Bacteroides fragilis, viridans group streptococci, Proteus species, Klebsiella pneumoniae, and Pseudomonas aeruginosa. It has also shown activity against anaerobic pathogens, with effectiveness similar to that of imipenem and meropenem.

"This is a significant new drug for hospitalized patients with serious bacterial infections," said Janet Woodcock, M.D., the Food & Drug Administration's chief medical officer and acting director of the Center for Drug Evaluation & Research. This is due to the growing problem of bacterial resistance. P. aeruginosa, the leading pathogen in nosocomial pneumonia, in particular, has increasing multidrug resistance.

Rosner is referring to data from the 47th Annual Interscience Conference on Antimicrobial Agents & Chemotherapy (ICAAC). The data showed that overall clinical cure rates were 68.3% for doripenem and 64.8% for imipenem. For those patients with P. aeruginosa infection, doripenem demonstrated a 65% clinical cure rate compared with a 36% clinical cure rate seen with imipenem.

Originally launched by Shionogi & Co. of Japan under the brand name Finibax in 2005, Doribax will be marketed by Ortho-McNeil. Doribax was granted fast-track status by the FDA in 2004 for the treatment of hospital-acquired pneumonia (HAP), including ventilator-associated pneumonia (VAP). In its approval, the FDA stated that doripenem has antimicrobial activity against gram-negative organisms resistant to other agents approved for the treatment of nosocomial pneumonia.

Note these precautions

The FDA demonstrated its concern for bacterial resistance in the product insert. Attached is a precaution to the indications that doripenem "should be used only to treat infections that are proven or strongly suspected to be caused by susceptible bacteria." In addition, patients taking the antiepileptic medication valproic acid should have their levels checked while on doripenem. It has been shown that doripenem may reduce serum valproic acid to subtherapeutic levels.

Common adverse reactions observed in the clinical trials of doripenem were headache, nausea, diarrhea, rash, and phlebitis. Recommended dosing is 500 mg every eight hours by intravenous infusion administered over one hour for patients 18 years of age and older. Doripenem will be available in 500-mg vials of sterile doripenem powder.

TIPS TO REMEMBER Doribax

THE AUTHOR is a writer based in Brooklyn, N.Y.