Dalbavancin
A lipoglycopeptide with a two-week half-life, meaning a single intravenous dose can treat an entire skin infection and send the patient home without a line.
Also known as lipoglycopeptide, dalba, Dalvance, Xydalba, BI-397, VER-001
Approved drug — Licensed by a major regulator for human use, with phase-3 trial data behind it.
FDA-approved in 2014 on the DISCOVER 1 and DISCOVER 2 randomised non-inferiority trials against vancomycin/linezolid in acute bacterial skin infection, with a later trial establishing the single 1500 mg dose. The 2025 DOTS randomised trial in JAMA found two doses of dalbavancin non-inferior to 4-8 weeks of standard IV therapy for complicated S. aureus bacteraemia, with fewer treatment discontinuations — good evidence for a use that remains off-label.
How it works
Dalbavancin is a semisynthetic derivative of the teicoplanin-family natural product A40926. It retains the classic glycopeptide mechanism — hydrogen bonding to the D-alanyl-D-alanine terminus of lipid II to block transglycosylation and transpeptidation — but adds a lipophilic side chain that tethers the molecule to the cell membrane, concentrating it at its target and giving MICs several-fold lower than vancomycin against staphylococci and streptococci. The same lipophilicity produces roughly 93% plasma protein binding and an extraordinarily long terminal half-life of about two weeks, which is the entire clinical point of the drug. It is inactive against vanA-type vancomycin-resistant enterococci but retains activity against vanB strains.
Targets: Lipid II D-Ala-D-Ala terminus, Bacterial cell membrane, Peptidoglycan transglycosylase
Dosing
| Protocol | Dose | Frequency | Route |
|---|---|---|---|
| Single-dose regimen for acute bacterial skin infectionInfused over 30 minutes. | 1500 mg | once, as a single dose | intravenous |
| Two-dose regimenEach dose infused over 30 minutes, one week apart. | 1000 mg | day 1, then 500 mg on day 8 | intravenous |
| Off-label deep-seated infection regimenTwo doses one week apart. | 1500 mg | on day 1 and day 8 | intravenous |
- · 1500 mg once. This is the regimen that made dalbavancin popular — one infusion in the emergency department or infusion centre replaces a 10-14 day course and often avoids admission entirely.
- · The original approved regimen: 1000 mg on day 1 followed by 500 mg on day 8. Equivalent in outcome to the single 1500 mg dose.
- · 1500 mg on days 1 and 8 is the regimen used in the DOTS randomised trial for complicated S. aureus bacteraemia and is increasingly used off-label for osteomyelitis and endocarditis in people who cannot keep a central line, including those with injection drug use.
Titration
Dose is reduced to 1125 mg (single-dose regimen) in patients with CrCl below 30 mL/min who are not on regular haemodialysis. No adjustment is needed for dialysis patients.
Cycling
One or two doses is a complete course. Because drug persists for weeks, there is no meaningful way to 'stop' therapy early if a problem arises — that is the trade-off for the convenience.
Pharmacology
- Half-life
- Terminal half-life of roughly 346 hours, about 14 days — one of the longest of any antibacterial drug.
- Onset
- Therapeutic concentrations are reached during the infusion itself; visible improvement in cellulitis is expected within 48 to 72 hours.
- Routes
- intravenous
- Molecule
- Semi-synthetic lipoglycopeptide, glycosylated heptapeptide core with a lipophilic side chain
- Sequence length
- 7 amino acids
- Molecular weight
- 1816.7 Da
Handling
- Diluent
- Sterile water for injection, then diluted in 5% dextrose
- Typical mix
- 25 or 25 mL
- Vial sizes
- 500 mg
- Lyophilised
- Room temperature, 20-25°C.
- Reconstituted
- Reconstituted and diluted solution stored at 2-25°C and used within 48 hours; do not freeze.
Mixing
Each 500 mg vial takes 25 mL of sterile water. Do not shake — swirl and invert until dissolved, which can take several minutes. The final infusion must be diluted in 5% dextrose, not saline; sodium chloride causes precipitation.
Side effects
- commonNausea— The most frequently reported adverse effect, in roughly 5% of patients.
- commonHeadache
- commonDiarrhoea
- uncommonInfusion reaction— Flushing, urticaria and back pain if infused too rapidly — the same histamine-release picture as vancomycin. Slowing or stopping the infusion resolves it.
- uncommonALT elevation— Usually transient and asymptomatic.
Do not use if
- Known hypersensitivity to dalbavancin; cross-reactivity with other glycopeptides is possible.
- Not appropriate as empirical monotherapy where gram-negative or anaerobic coverage is needed — the spectrum is strictly gram-positive.
- Poor choice when a rapidly reversible agent is preferred, such as in undiagnosed fever, because the drug cannot be withdrawn once given.
Combining it
- redundantvancomycin — Same target and overlapping spectrum; there is no rationale for both.
- redundantoritavancin — Direct competitors in the same single-dose lipoglycopeptide niche. Dalbavancin does not interfere with coagulation assays, which is a practical advantage over oritavancin.
What to monitor
- · Liver enzymes if therapy is repeated or the patient has existing hepatic disease.
- · Renal function at baseline to determine whether the reduced dose applies.
- · Clinical response at 48-72 hours — since there is no daily contact, an explicit follow-up plan matters more than usual.
Legal status
Prescription-only injectable, approved in the US (2014) and EU (2015) for acute bacterial skin and skin-structure infections. Use outside that indication is off-label.
References
- Boucher et al. 2014, DISCOVER 1 and 2 trials of dalbavancin for skin infection (trial)
- Turner et al. 2025, DOTS randomised trial of dalbavancin for S. aureus bacteraemia, JAMA (trial)
- Dalvance (dalbavancin) US prescribing information (label)
Mechanism in depth
A lipoglycopeptide: the vancomycin D-Ala-D-Ala binding mechanism plus a lipophilic side chain that anchors it in the membrane and binds albumin. The anchoring raises potency; the albumin binding produces a terminal half-life of roughly two weeks, which is the entire clinical point - a single dose covers a course.
What usually goes wrong
The long half-life cuts both ways. It removes adherence as a variable, which is why it is used in people who will not complete an outpatient course - but if an adverse reaction occurs there is no way to withdraw the drug, and it is still present weeks later. It also has no useful Gram-negative activity, so it is not a monotherapy for an undiagnosed cellulitis with systemic features.
Bloodwork worth running
| Marker | When | Why it matters |
|---|---|---|
| Liver enzymes | Baseline; repeat only if clinically indicated given the single-dose schedule. | Transaminase elevation is the most commonly reported laboratory abnormality. |
Pharmacokinetics
- Protein binding
- 93%
- Crosses blood-brain barrier
- no
- Accumulates
- Yes — doses stack before steady state
- Elimination
- Mixed
Receptor targets
- D-Ala-D-Ala peptidoglycan terminus — Higher than vancomycin due to membrane anchoring
Blocks cell wall cross-linking
What to expect, and when
Therapeutic concentrations immediately after infusion, sustained for one to two weeks from a single dose.
Genuinely uncertain
- Its role in bacteraemia and osteomyelitis is expanding on observational data rather than randomised evidence.