Efficacy and Safety of Tedizolid and Linezolid for the Treatment of Acute Bacterial Skin and Skin Structure Infections in Injection Drug Users: Analysis of Two Clinical Trials.

INTRODUCTION

Injection drug users (IDUs) often develop acute bacterial skin and skin structure infections (ABSSSI) and use emergency departments as their primary source for medical care.

METHODS

A post hoc subgroup analysis of two randomized trials examined the efficacy and safety of tedizolid in the treatment of ABSSSI in IDUs. IDUs (n = 389) were identified from two pooled phase 3 trials (NCT01170221, NCT01421511) in patients with ABSSSI (n = 1333). Patients were randomly assigned to tedizolid phosphate (200 mg once daily, 6 days) or linezolid (600 mg twice daily, 10 days). Primary endpoint was ≥ 20% reduction in lesion area from baseline at 48 -72 h. Secondary endpoints included investigator-assessed clinical and microbiological response at the post-therapy evaluation (PTE).

RESULTS

Wound infection was more common in IDUs (52.2%), while cellulitis/erysipelas was more common in non-IDUs (55.9%). Most infections were due to Staphylococcus aureus (IDUs, 75.2%; non-IDUs, 85.6%), while oral pathogens were more prevalent in IDUs. Early clinical success rates for tedizolid and linezolid were 82.5% and 79.6% in IDUs and 81.3% and 79.3% for non-IDUs, respectively; responses at PTE were similar. Microbiological response per pathogen was similar between treatment groups. Rates of treatment-emergent adverse events (AEs) in IDUs were comparable between tedizolid (46.2%) and linezolid (47.8%) arms, while lower incidence of gastrointestinal AEs was observed with tedizolid (20.3%) than with linezolid (25.1%).

CONCLUSION

Efficacy and safety of tedizolid and linezolid in the treatment of ABSSSI was similar in IDUs and non-IDUs, supporting the use of oxazolidinones in treating ABSSSIs in IDUs.

FUNDING

Merck & Co., Inc., Kenilworth, NJ, USA.