386. Doripenem 1 g infused for 4 hours (h) in the Treatment of Nosocomial Pneumonia/Ventilator Associated Pneumonia (NP/VAP) due to Acinetobacter baumannii (A. baumannii)
Session: Poster Session: Hospital-acquired and Transplant Infections
Friday, October 30, 2009: 12:00 AM
Room: Poster Hall A
Background: A baumanii is an “ESKAPE” pathogen, labeled as such due to a lack of potentially effective antibacterials1. Doripenem has activity against A. baumannii with a breakpoint of 1µg/mL based on a 500 mg dose infused for 1h. PK/PD target attainment studies suggest that doripenem 1g infused for 4 h may be effective against higher MIC pathogens, up to 8 or 16 µg/ml.
Methods: A prospective, noncomparative study of doripenem 1g infused for 4h was conducted to evaluate its efficacy in NP/VAP subjects with risk factors for infection with gram negative pathogens. Culture and susceptibility testing were conducted for all baseline pathogens. Subjects were evaluated for overall clinical and microbiological success and success by pathogen at the test of cure visit, 10-14 days posttherapy.
Results: In the microbiological evaluable (ME) population 14 subjects had A. baumannii isolated at study entry and MIC data were available for all 14 isolates. Microbiologic outcome by MIC is shown in the table. No A. baumannii isolates developed resistance to doripenem.
Table: Eradication of A baumannii by doripenem study entry MIC
A. baumanniiMicrobiologic Response
MIC (µg/mL)Subjects (N)Eradicated
n (%)
Persisted
n (%)
≤0.03000
0.06000
0.1211 (100)0
0.25000
0.5011 (100)0
1.011 (100)0
2.011 (100)0
4.0000
8.011 (100)0
1622 (100)0
3221 (50.0)1 (50.0)
>3253 (60.0)2 (40.0)
Total1411 (78.6)3 (21.0)

Conclusion: There was 100% eradication of A. baumannii with MICs up to 16 µg/mL with doripenem 1g infused over 4h.
1Boucher HW et al. Clin Infect Dis. 2009;48:1-12.
Mary Ambruzs, RN, BSN1, Susan Nicholson, MD2, Janet Peterson, PhD1, Jim Xiang, PhD1, Behin Yektashenas, PharmD1 and  S. C. Nicholson,
Ortho-McNeil Janssen Scientific Affairs, LLC Role(s): Employee, Received: Salary.
J. Peterson,
Ortho-McNeil Janssen Scientific Affairs, LLC Role(s): Employee, Received: Salary.
M. Ambruzs,
Ortho-McNeil Janssen Scientific Affairs, LLC Role(s): Employee, Received: Salary.
B. Yektashenas,
Ortho-McNeil Janssen Scientific Affairs, LLC Role(s): Employee, Received: Salary.
J. Xiang,
Ortho-McNeil Janssen Scientific Affairs, LLC Role(s): Employee, Received: Salary., (1)Ortho McNeil Janssen Scientific Affairs, LLC, Raritan, NJ, (2)Ortho-McNeil Janssen Scientific Affairs