Efficacy of IV/oral moxifloxacin in the treatment of complicated skin and skin-structure infections: results of the RELIEF study

Abstract number: P1785

Gyssens I.C., Dryden M., Kujath P., Nathwani D., Schaper N., Arvis P., Reimnitz P., Alder J., Hampel B.

Objectives: Selection of the optimal antimicrobial for treatment of complicated skin and skin structure infections (cSSSIs) can be difficult. A number of IV antimicrobials have been investigated for the management of cSSSIs. Amongst them, moxifloxacin (MXF) has been shown to have efficacy similar to standard therapies. The RELIEF study was conducted to provide additional data in well-characterised patients with confirmed cSSSIs.

Methods: RELIEF was a prospective, randomised, double-dummy, double-blind, multinational, multicentre study enrolling patients with a diagnosis of major abscess, diabetic foot infection, wound infection or infected ischaemic ulcer. Patients were stratified according to infection severity, requirement for surgery, and cSSSI diagnosis, and randomised to IV/PO MXF 400 mg qd or piperacillin/tazobactam 4.0/0.5 g tds followed by PO amoxicillin-clavulanic acid (PIP/TAZ-AMC) 875/125 mg bd, for 7–21 days. The primary efficacy variable was clinical response 14–28 days after completion of therapy. Non-inferiority of MXF was demonstrated if the lower limit of the 95% confidence interval (CI) was above -10%.

Results: Of 813 patients randomised (MXF=432, PIP/TAZ-AMC=381), 803 were valid for ITT/safety analyses (MXF=426, PIP/TAZ-AMC=377). In the PP population (MXF=363, PIP/TAZ-AMC=307), diagnoses were: abscess (n = 320, 47.8%), diabetic foot infection (n = 207, 30.9%), wound infection (n = 110, 16.4%), and infected ulcer (n = 33, 4.9%). The most frequent individual pathogens in the microbiologically valid (MBV) population were: methicillin-susceptible Staphylococcus aureus (n = 308), Escherichia coli (n = 113), Enterococcus faecalis (n = 110), Streptococcus pyogenes (n = 60) and Bacteroides fragilis (n = 44). For the primary efficacy variable (clinical response at TOC), MXF was non-inferior to PIP/TAZ-AMC (Table). Good bacteriological efficacy was also seen (Table).

In the ITT/safety population, incidences of treatment-emergent adverse events, and treatment-emergent drug-related adverse events were similar in the MXF and PIP/TAZ-AMC groups (23% vs 19%, P = 0.14, and 9% vs 7%, P = 0.60, respectively).

Conclusion: In this large multicentre study, IV/PO MXF was clinically non-inferior to IV PIP/TAZ-AMC in the treatment of patients with cSSSIs. Both treatments were well tolerated. Safety profiles of study regimens were similar. These data confirm the efficacy of IV/PO MXF for the treatment of cSSSIs.

Table: Clinical and bacteriological response in the different patient populations of the RELIEF study

PopulationsMXFPIP/TAZ-AMC95% CI
 n/N (%)n/N (%) 
Clinical response   
  Per-protocol322/363 (88.7)275/307 (89.6)-5.2, 4.0
  MBV235/270 (87.0)215/243 (88.5)-7.4, 3.5
  ITT353/426 (82.9)305/377 (80.9)-3.1, 7.0
  ITT with organisms256/313 (81.8)234/290 (80.7)-5.2, 6.6
Bacteriological response   
  MBV224/270 (83.0)210/243 (86.4)-10.2, 1.7
  ITT with organisms244/313 (78.0)227/290 (78.3)-7.5, 5.0

Session Details

Date: 16/05/2009
Time: 00:00-00:00
Session name: 19th European Congress of Clinical Microbiology and Infectious Diseases
Location: Helsinki, Finland, 16 - 19 May 2009
Presentation type:
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