Randomized-controlled Trial (RCT) on Combination Antibiotic for Infections Caused by Gram-negative Bacteria

Summary

Background and rationale: Antimicrobial resistance is a global public health threat. An increasing number of Gram-negative bacteria isolates worldwide are resistant to virtually all antibiotics including carbapenems. Although polymyxins are the current gold standard antibiotic for treatment of severe extensively drug-resistant Gram-negative bacteria (XDR-GNB - defined in Appendix I) infections, resistance development on therapy and treatment failures are common. Combination antibiotics therapy have better in vitro efficacy, but have not been formally tested in a prospective trial. We will conduct a Phase IIB, prospective, open-label, randomized-controlled trial in 4 major Singaporean hospitals, with balanced treatment assignments achieved by permuted block randomization, stratified by hospital. There will be 75 subjects per arm, with the subjects in the comparator arm receiving standard-dose polymyxin B while the intervention arm will receive a second antibiotic, doripenem, with polymyxin B against the bacterial isolate in question. Subjects with ventilator-associated pneumonia (VAP) will additionally receive nebulized colistin. The primary outcome is 30-day mortality while secondary outcomes include microbiological clearance, time to defervescence, and toxicity of therapy, presence of secondary infections due to new multi-drug resistant bacteria and length of ICU stay. Plasma drug levels will be measured by liquid chromatography-mass spectrometry. Hypothesis: The underlying primary hypothesis is that combination antibiotic therapy (IV polymyxin B + IV doripenem) is superior to mono-antibiotics therapy (IV polymyxin B) in reducing 30-day mortality from XDR-GNB infections.

Timeline

Start

2015-01

Primary completion

2015-10

Completion

2015-12

Publications

• Background Boucher HW. Challenges in anti-infective development in the era of bad bugs, no drugs: a regulatory perspective using the example of bloodstream infection as an indication. Clin Infect Dis. 2010 Jan 1;50 Suppl 1:S4-9. doi: 10.1086/647937.
• Background Magiorakos AP, Srinivasan A, Carey RB, Carmeli Y, Falagas ME, Giske CG, Harbarth S, Hindler JF, Kahlmeter G, Olsson-Liljequist B, Paterson DL, Rice LB, Stelling J, Struelens MJ, Vatopoulos A, Weber JT, Monnet DL. Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard definitions for acquired resistance. Clin Microbiol Infect. 2012 Mar;18(3):268-81. doi: 10.1111/j.1469-0691.2011.03570.x. Epub 2011 Jul 27.
• Background Hsu LY, Tan TY, Jureen R, Koh TH, Krishnan P, Tzer-Pin Lin R, Wen-Sin Tee N, Tambyah PA. Antimicrobial drug resistance in Singapore hospitals. Emerg Infect Dis. 2007 Dec;13(12):1944-7. doi: 10.3201/eid1312.070299.
• Background Koh TH, Khoo CT, Tan TT, Arshad MA, Ang LP, Lau LJ, Hsu LY, Ooi EE. Multilocus sequence types of carbapenem-resistant Pseudomonas aeruginosa in Singapore carrying metallo-beta-lactamase genes, including the novel bla(IMP-26) gene. J Clin Microbiol. 2010 Jul;48(7):2563-4. doi: 10.1128/JCM.01905-09. Epub 2010 May 12.
• Background Koh TH, Khoo CT, Wijaya L, Leong HN, Lo YL, Lim LC, Koh TY. Global spread of New Delhi metallo-beta-lactamase 1. Lancet Infect Dis. 2010 Dec;10(12):828. doi: 10.1016/S1473-3099(10)70274-7. No abstract available.

Drugs

Indications