Oritavancin
A single-infusion antibiotic for serious skin infections
Oritavancin is a lipoglycopeptide antibiotic that attacks Gram-positive bacteria in several ways at once and stays in the body for weeks. One 1,200 mg infusion treats an acute skin infection, but it interferes with blood-clotting tests for up to two days.
What is it?
Oritavancin binds the cell-wall precursor that vancomycin targets, binds a second site in the peptidoglycan bridge, and disrupts the bacterial membrane. That multiple attack gives rapid killing, and a terminal half-life of about 245 hours means a single dose covers the whole course.
In SOLO I, 954 patients received a single oritavancin dose or 7 to 10 days of vancomycin: the primary endpoint was met by 82.3% against 78.9%, within the noninferiority margin, with similar results for MRSA. SOLO II repeated the result in 1,005 patients (80.1% against 82.9%). Pooled safety across 976 oritavancin and 983 vancomycin patients was similar.
The label's first warning is unusual: oritavancin interferes with laboratory clotting tests, falsely prolonging them for up to 48 hours, and it may increase bleeding risk with warfarin. It is not for osteomyelitis, where more cases occurred in the oritavancin arm of the trials.
The two oritavancin products are not prepared the same way. Orbactiv is given as 1,200 mg over three hours; the label states that Kimyrsa differs in dose strength, infusion duration and preparation, including which diluents are compatible, and that each product's own instructions must be followed. Confusing them is a dispensing hazard rather than a theoretical one.
At a Glance
Every value in this table is printed from the Grey Peptides dataset, the same record the compound explorer and comparison tool read, so the three can never disagree.
Educational information, not medical advice. The doses on this page come from approved labels, published studies and, where no study exists, amounts reported by users. None is a recommendation for you. An unapproved compound has no established safe or effective human dose, and products sold for “research use only” are not made or tested for people. Talk to a doctor before acting on anything on this site, including before you start, stop or change any medicine or dose. Full medical disclaimer.
Half-Life: How Much Remains
The dataset records a half-life of terminal half-life about 245 hours for Oritavancin. After each half-life, half of what was in the circulation is gone, so about 3% remains after five. Real clearance varies with the person, the dose, the route and kidney or liver function; this is arithmetic on a published figure, not a dosing tool.
Published Research
The studies behind oritavancin, from their PubMed abstracts.
SOLO I: one dose against 7 to 10 days of vancomycin
In 954 patients, all three efficacy endpoints met the 10-point noninferiority margin: the primary endpoint 82.3% against 78.9%, investigator-assessed cure 79.6% against 80.0%, and lesion reduction 86.9% against 82.9%, with similar results by pathogen including MRSA.
SOLO II
In 1,005 patients, the primary composite endpoint was 80.1% on oritavancin and 82.9% on vancomycin, investigator-assessed cure 82.7% against 80.5% and lesion reduction 85.9% against 85.3%, all within the noninferiority margin, with similar adverse-event rates.
Pooled safety from both trials
Across 976 oritavancin-treated and 983 vancomycin-treated patients, the incidences of adverse events, serious adverse events and discontinuations were compared, supporting the single-dose regimen's tolerability.
Side Effects & Contraindications
Reported Side Effects
From the studies above.
Contraindications & Cautions
Warnings from the Orbactiv label (DailyMed, effective September 15, 2026).
Legal Status
Oritavancin is an approved prescription drug in the US.
Frequently Asked Questions
?How many doses of oritavancin are needed?
One. A single 1,200 mg intravenous infusion treats an acute bacterial skin and skin structure infection, because the drug's terminal half-life is about 245 hours.
?Why does oritavancin affect blood tests?
It binds to reagents used in laboratory clotting tests, falsely prolonging results for up to 48 hours. Its label warns about this first, and about bleeding risk with warfarin.
?What is the difference between Orbactiv and Kimyrsa?
They are two oritavancin products that differ in dose strength, infusion duration and preparation instructions. The label says to follow each product's own instructions.
?Is oritavancin used for bone infection?
No. The Orbactiv label warns that more cases of osteomyelitis were reported in the oritavancin arm of its trials, and that patients with suspected or confirmed osteomyelitis should be treated according to standard of care.
References
- [fda] US FDA, Drugs@FDA (openFDA): KIMYRSA, NDA 214155 (March 12, 2021), a second oritavancin product. Read October 3, 2026.
- [fda-pi] FDA. Orbactiv (oritavancin) US prescribing information (DailyMed set ff09a726-9f9b-4e30-b509-396781293220, effective September 15, 2026). Read October 3, 2026.
- [clinical-trial] Corey GR, et al. "Single-dose oritavancin in the treatment of acute bacterial skin infections." N Engl J Med, 2014;370(23):2180-90. PMID: 24897083.
- [clinical-trial] Corey GR, et al. "Single-dose oritavancin versus 7-10 days of vancomycin in the treatment of gram-positive acute bacterial skin and skin structure infections: the SOLO II noninferiority study." Clin Infect Dis, 2015;60(2):254-62. PMID: 25294250.
- [pubmed] Corey GR, et al. "Single Intravenous Dose of Oritavancin for Treatment of Acute Skin and Skin Structure Infections Caused by Gram-Positive Bacteria: Summary of Safety Analysis from the Phase 3 SOLO Studies." Antimicrob Agents Chemother, 2018;62(4). PMID: 29358292.
Sources & Citations
Studies were read from their PubMed records; regulatory sources are listed below, read October 3, 2026.
Medical Disclaimer: This content is for educational and informational purposes only. It is not medical advice, and nothing here is an instruction to obtain or use any compound. Consult a licensed healthcare provider before making health decisions.