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Co et al
difference between the oritavancin and vancomycin groups.4,5
The overall frequency of adverse events was also similar
between treatment groups. The confirmation of noninferiority of oritavancin to vancomycin by these studies suggests
that single-dose oritavancin provides an alternative to multidose antibiotic therapy for treatment of ABSSTIs.
Based on this data and potential for cost savings, oritavancin was added to the formulary of our large community
hospital in June 2015 as an option to reduce admissions due
to ABSSTIs. The objective of this analysis was to evaluate
the use of oritavancin within our hospital since its addition to
formulary, and to determine the financial impact of oritavancin use to the institution.

Methods
In this study approved by our hospital Institutional Review
Board, a retrospective chart review was used to obtain data
for all patients who had received oritavancin through our
health system from June 2015 to October 2016. Data were
collected from the hospital electronic medical records
(EMRs), as well as from clinical notes documented in our
pharmacy surveillance software. A drug utilization report
was generated from the EMR and used to identify all patients
who had received oritavancin during the specified time
period. Based on this report, 67 patients were identified and
included in the study. The following data points were collected for each patient: age, gender, prior antibiotic use, indication for oritavancin, prescriber, and admission dates.
The primary outcome of the study was to determine the
appropriateness of oritavancin use by indication, using institution-specific restricted antimicrobial criteria for use for
oritavancin. Based on these criteria for use and FDAapproved indication, oritavancin use was considered appropriate if used in the treatment of patients with ABSSTIs,
including cellulitis, cutaneous abscess, and wound infections. Use in patients for the treatment of non-FDA-approved
indications, such as osteomyelitis and bacteremia, was considered inappropriate for the purpose of this study.
Secondary outcomes included the number of readmissions in patients treated with oritavancin and the financial
impact of oritavancin use to our institution. A readmission
was documented for any patient who returned to our health
system within 14 days of oritavancin administration.
Readmission data were only collected for patients who presented back with complaints of the same infectious process.
Potential financial benefit was calculated by comparing
the cost of hospitalization for inpatient treatment of an
ABSSTI with the cost of a dose of oritavancin. The cost of
inpatient treatment was calculated by multiplying the duration of hospitalization (in days) by the cost-per-day of a hospital bed. Potential financial benefit was assessed using 340B
pricing for drug acquisition cost and a national average for
cost-per-day for treatment of ABSSTIs. An institution-specific length of stay (6.62 days) was calculated using

Table 1. Indications for Oritavancin Use.
Indication
Cellulitis
Abscess
Cardiac device infectionb
Diabetic foot infection
Miscellaneous SSTIc
Septic arthritis
Osteomyelitis
Bacteremia

No. of patients (%)a
37 (49.3)
8 (10.6)
7 (9.3)
3 (4.0)
4 (6.6)
5 (7.5)
8 (10.6)
3 (4.0)

Note. SSTI = skin and soft tissue infection.
a
Patients with 2 indications were included in both categories.
b
Redness and swelling around the surgical site of a recently implanted
cardiac device.
c
Includes knee infection, leg wound (unspecified), folliculitis, ulcer
(unspecified).

admissions with diagnosis codes for skin and soft tissue
infections over the last year.

Results
A total of 67 patients were identified and included in this
study. Of these patients, 41 (61%) were male and 26 (39%)
were female. Patient age ranged from 19 to 90 years old, with
a mean age of 52.3 years old for this population. The majority of patients (90%) received oritavancin as outpatients
through our outpatient infusion center and in the ED; a
smaller portion of the patients (10%) were given the drug in
the inpatient setting, just prior to discharge. A total of 41
patients (61%) had previous antibiotic use prior to receiving
oritavancin therapy; this includes both intravenous and oral
medications, and only those intended to treat the infection
for which oritavancin was eventually prescribed.
A list of the indications for which oritavancin was prescribed in this population is reported in Table 1. In this population, 51 (76%) patients received oritavancin for an
indication which was considered appropriate. In contrast, 16
(24%) received oritavancin for an inappropriate indication.
The most common appropriate indication for which oritavancin was used was cellulitis (49.3%), whereas the most
common inappropriate indication was osteomyelitis (10.6%).
Prescribing patterns by department are as follows: 6 (9%)
of orders prescribed by hospitalists, 17 (25%) prescribed by
ED physicians, 8 (12%) prescribed by cardiologists, and 36
(54%) prescribed by infectious disease physicians. Infection
disease physicians include both our hospital-employed infectious disease group and a private infectious disease group
who see patients at our institution. Prescribing patterns of
inappropriate use, described by department, are shown in
Figure 1.
There were no patients who had to be readmitted to our
facilities within 14 days of oritavancin therapy. A total of 8
patients (12%) presented back to the ED with complaints of

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