SOLO I : Single-dose oritavancin in the treatment of acute bacterial skin infections.
- SOLO I : Single-dose oritavancin in the treatment of acute bacterial skin infections.
P : adults with acute bacterial skin and skin-structure infections
E : a single intravenous dose of 1200 mg of oritavancin. n=475
C : intravenous vancomycin twice daily for 7 to 10 days. n=479
The mean (±SD) total daily vancomycin dose in the safety population was 2.3±0.94 g, and the mean duration of vancomycin therapy was 8.1±2.43 days. The mean vancomycin level in patients with a measurable trough level (before administration of the fourth dose) was 15.4 μg per milliliter, and the median level 11.1 μg per milliliter.
primary end point, 82.3% versus 78.9% (95% confidence interval [CI] for the difference, -1.6 to 8.4 percentage points)
The primary composite end point was defined as cessation of spreading or reduction in lesion size, absence of fever, and no need for administration of a rescue antibiotic 48 to 72 hours after administration of oritavancin
The overall frequency of adverse events was also similar, although nausea was more common among those treated with oritavancin.
T : randomized, double-blind trial, noninferiority
There are several limitations of the SOLO I study.
Whereas the extended half-life of oritavancin provides the physician with a single infusion option for treatment, it also raises concern about extended illness, should a serious reaction to this antibiotic occur. The evidence to date suggests that oritavancin has a safety profile that is similar to the profile for vancomycin, and the 60-day follow-up assessment in our study, involving nearly 500 patients treated with oritavancin, did not identify any such prolonged adverse events; however, experience with this treatment is limited. Similarly, the inability to “step down” to a beta-lactam antibiotic once the possibility of MRSA infection has been ruled out has the potential to result in increased microbial resistance. Further evaluation of this possibility will be important. Whether patients treated with a single infusion can be discharged and followed on an outpatient basis remains to be determined. Several questions must be answered; for example, is there a risk that outpatient follow-up will delay the diagnosis of serious, deep infections such as necrotizing fasciitis and bacteremia? Serious infections such as bacteremia, which were once considered manageable only in a hospital setting, have since shown the potential to be effectively managed on an outpatient basis once the patient's condition has stabilized. Also, studies are needed to determine whether treatment with oritavancin is effective for other infections, such as bacteremia, osteomyelitis, and prosthetic-joint infections.