Dalbavancin Baxter

What Is Dalbavancin Baxter and What Is It Used For?

Dalbavancin belongs to the lipoglycopeptide class of antibiotics, which are structurally related to vancomycin but have been chemically modified to improve their antibacterial activity and pharmacokinetic properties. It was first approved by the United States Food and Drug Administration (FDA) in 2014 under the brand name Dalvance, and subsequently by the European Medicines Agency (EMA) under the brand name Xydalba. Dalbavancin Baxter is a generic formulation manufactured by Baxter that contains the same active substance.

The primary indication for dalbavancin is the treatment of acute bacterial skin and skin structure infections (ABSSSI) in adults and children aged 3 months and older. ABSSSI encompasses a range of serious skin infections including cellulitis or erysipelas with a minimum lesion surface area of approximately 75 cm², wound infections, and major cutaneous abscesses. These infections are predominantly caused by Gram-positive bacteria, particularly Staphylococcus aureus (including methicillin-resistant strains, MRSA), Streptococcus pyogenes, Streptococcus agalactiae, and the Streptococcus anginosus group.

The mechanism of action of dalbavancin involves binding to the terminal D-alanyl-D-alanine residues of the stem pentapeptide in nascent peptidoglycan, thereby preventing the transglycosylation and transpeptidation steps essential for bacterial cell wall synthesis. What distinguishes dalbavancin from older glycopeptides such as vancomycin is the presence of a lipophilic side chain that anchors the molecule to the bacterial cell membrane. This structural modification enhances binding affinity, increases bactericidal potency, and extends the drug's half-life to approximately 346 hours (14.4 days), which is the longest among currently approved antibiotics.

In pivotal clinical trials (DISCOVER 1 and DISCOVER 2), dalbavancin demonstrated non-inferiority to vancomycin followed by oral linezolid for the treatment of ABSSSI, with comparable clinical cure rates of approximately 97% in the clinically evaluable population. The convenience of its dosing schedule represents a significant advantage, as patients can receive a single 30-minute infusion and then be discharged, rather than requiring 7-14 days of daily intravenous antibiotic therapy in a hospital setting. This approach has been shown to reduce healthcare costs and improve patient satisfaction.

It is important to note that dalbavancin has no meaningful activity against Gram-negative bacteria. Therefore, in patients with polymicrobial infections that include Gram-negative organisms, dalbavancin must be combined with an appropriate Gram-negative-active agent. The drug should also not be used for non-bacterial infections, and its use should be guided by culture and susceptibility results whenever possible to promote antimicrobial stewardship.

What Should You Know Before Taking Dalbavancin Baxter?

Contraindications

Dalbavancin Baxter is contraindicated in patients with a known hypersensitivity to dalbavancin or to any of the excipients in the formulation. Patients who have experienced serious allergic reactions to other glycopeptide antibiotics, such as vancomycin or teicoplanin, should be closely monitored if dalbavancin is considered, as cross-reactivity may occur. Although cross-sensitivity between glycopeptides is not universally observed, healthcare providers should exercise caution and have resuscitation equipment available during the first administration.

There are no absolute contraindications related to age for adults, and the drug has been approved for pediatric use in children aged 3 months and older based on pharmacokinetic and safety studies. However, dalbavancin has not been adequately studied in neonates and infants younger than 3 months, and use in this population is not recommended.

Warnings and Precautions

Clostridioides difficile-associated diarrhea (CDAD): As with nearly all antibiotics, dalbavancin can alter the normal intestinal flora and lead to overgrowth of Clostridioides difficile, resulting in diarrhea that may range from mild to life-threatening pseudomembranous colitis. Patients who develop diarrhea during or after treatment should be evaluated for CDAD, and appropriate management should be initiated promptly. Mild cases may respond to discontinuation of the offending antibiotic, while more severe presentations require treatment with oral vancomycin or fidaxomicin.

Hepatic effects: Elevations in alanine aminotransferase (ALT) greater than three times the upper limit of normal have been observed in clinical trials. Liver function should be monitored in patients who develop signs or symptoms of hepatotoxicity, such as jaundice, dark urine, or right upper quadrant abdominal pain. In patients with pre-existing hepatic impairment, no dosage adjustment is required for mild to moderate impairment (Child-Pugh Class A or B), but caution is advised in severe impairment (Child-Pugh Class C) due to lack of clinical data.

Renal impairment: For patients with chronic renal impairment and an estimated creatinine clearance less than 30 mL/min who are not receiving regular hemodialysis, the recommended dose of dalbavancin should be reduced to 1125 mg as a single dose or 750 mg followed by 375 mg one week later. No dosage adjustment is needed for patients on regular hemodialysis, as dalbavancin is not significantly removed by dialysis.

Infusion-related reactions: Dalbavancin should be administered by intravenous infusion over a minimum of 30 minutes. Rapid infusion may result in upper body flushing, urticaria, pruritus, and rash (sometimes referred to as "Red Man Syndrome" or "Red Person Syndrome"), similar to reactions observed with vancomycin. Slowing or temporarily stopping the infusion typically resolves these symptoms.

Antimicrobial resistance: As with all antibiotics, use of dalbavancin may promote the development of resistant organisms. The drug should be prescribed only when infection is proven or strongly suspected to be caused by susceptible bacteria. Unnecessary use contributes to antimicrobial resistance, a major global public health threat identified by the World Health Organization.

Pregnancy and Breastfeeding

There are limited clinical data on the use of dalbavancin during pregnancy. Animal reproductive toxicology studies conducted in rats and rabbits at doses up to 3.5 times the human equivalent dose did not reveal evidence of direct harm to the fetus or impaired fertility. However, animal studies are not always predictive of human response, and dalbavancin should only be used during pregnancy if the potential benefit outweighs the potential risk to the fetus.

It is not known whether dalbavancin is excreted in human breast milk. In animal studies, dalbavancin was detected in the milk of lactating rats. Given the potential for adverse effects on the breastfed infant, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother. Healthcare providers should weigh the severity of the infection and the availability of alternative treatments when counseling breastfeeding patients.

How Does Dalbavancin Baxter Interact with Other Drugs?

In vitro studies have shown that dalbavancin is not metabolized by cytochrome P450 (CYP) enzymes and does not significantly inhibit or induce CYP1A2, CYP2C9, CYP2C19, CYP2D6, or CYP3A4. Consequently, the potential for pharmacokinetic drug-drug interactions is low. However, several clinically relevant considerations should be taken into account when administering dalbavancin alongside other medications.

Dalbavancin is approximately 93% protein-bound, primarily to albumin. Highly protein-bound co-administered drugs could theoretically compete for binding sites, although clinically significant displacement interactions have not been demonstrated in pharmacokinetic studies. Nonetheless, awareness of this potential is important in patients taking multiple highly protein-bound medications.

Major Interactions

Minor Interactions

What Is the Correct Dosage of Dalbavancin Baxter?

Dalbavancin Baxter is supplied as a powder for concentrate for solution for infusion. It must be reconstituted and then further diluted in 5% dextrose solution before administration as an intravenous infusion over 30 minutes. The drug should never be administered as an intravenous bolus injection. Healthcare professionals must ensure the correct preparation technique to maintain sterility and drug stability.

Adults

Children (3 Months to <18 Years)

Dosing in pediatric patients is based on body weight and age. The EMA-approved pediatric dosing is as follows:

Elderly Patients

No dosage adjustment is required for elderly patients based on age alone. However, elderly patients are more likely to have decreased renal function, and creatinine clearance should be assessed prior to dosing. If estimated creatinine clearance is less than 30 mL/min and the patient is not receiving regular hemodialysis, the dose should be reduced as described in the renal impairment section below.

Renal Impairment Dosage Adjustment

Missed Dose

If a patient on the two-dose regimen misses the second dose on Day 8, the 500 mg dose should be administered as soon as possible. Clinical data suggest that the second dose can be given up to several days after the scheduled Day 8 without significantly compromising efficacy, due to the drug's very long half-life. However, patients should contact their healthcare provider for guidance on the optimal timing. The single-dose regimen eliminates concerns about missed doses entirely.

Overdose

There is no specific antidote for dalbavancin overdose. In the event of an overdose, treatment should be supportive, with monitoring of vital signs, renal function, and hepatic function. Due to its high protein binding (approximately 93%), dalbavancin is not significantly removed by hemodialysis. In clinical studies, single doses of up to 1500 mg were well tolerated, and the safety margin of dalbavancin is considered to be relatively wide compared with other glycopeptide antibiotics.

What Are the Side Effects of Dalbavancin Baxter?

The safety profile of dalbavancin has been established in multiple phase II and phase III clinical trials involving over 3,000 patients. Overall, dalbavancin is well tolerated, with the majority of adverse reactions being mild to moderate in severity and self-limiting. The incidence of treatment discontinuation due to adverse events was comparable to that observed with vancomycin/linezolid comparator regimens in pivotal trials.

The following side effects are categorized by frequency according to the convention used by the European Medicines Agency (EMA) and the Council for International Organizations of Medical Sciences (CIOMS): Very common (≥1/10), Common (≥1/100 to <1/10), Uncommon (≥1/1,000 to <1/100), Rare (<1/1,000).

In post-marketing surveillance, additional rare adverse events have been reported, though causality has not always been established. Patients should report any unexpected symptoms to their healthcare provider. The long half-life of dalbavancin means that adverse effects, if they occur, may persist for a longer duration compared with shorter-acting antibiotics. This is an important consideration for clinical management.

It is also worth noting that the incidence of Clostridioides difficile-associated diarrhea was not significantly higher with dalbavancin compared with vancomycin/linezolid in clinical trials, which is reassuring given the concern about antibiotic-associated colitis. Nevertheless, patients should be counseled to report any diarrhea occurring during treatment or in the weeks following completion of therapy.

How Should You Store Dalbavancin Baxter?

Dalbavancin Baxter is supplied as a lyophilized (freeze-dried) powder in single-use glass vials containing 500 mg of dalbavancin. Proper storage is essential to maintain the drug's stability and efficacy. The following storage guidelines should be followed:

• Unopened vials: Store at or below 25°C (77°F). Do not freeze. Keep the vial in the outer carton to protect from light.
• After reconstitution: The reconstituted solution in the vial should be used promptly or may be stored refrigerated at 2-8°C (36-46°F) for up to 48 hours. Do not freeze the reconstituted solution.
• After dilution: Once diluted in 5% dextrose infusion solution, the diluted solution may be stored at room temperature (up to 25°C) for up to 48 hours, or refrigerated at 2-8°C for up to 48 hours. The combined storage time in the vial and in the infusion bag should not exceed 48 hours at room temperature or 48 hours refrigerated.
• Do not use if the reconstituted solution appears discolored, cloudy, or contains particulate matter.
• Disposal: Single-use vials only. Any unused solution should be discarded in accordance with local regulations for pharmaceutical waste. Do not save unused portions for later use.

As with all injectable medications, dalbavancin should be prepared under aseptic conditions by trained healthcare professionals. Patients do not self-administer this medication at home under typical circumstances; it is administered in hospital or outpatient infusion center settings. If you have any concerns about the storage or preparation of your medication, consult your pharmacist or healthcare provider.

Keep all medicines out of the sight and reach of children. Do not use dalbavancin after the expiry date stated on the vial and carton. The expiry date refers to the last day of that month.

What Does Dalbavancin Baxter Contain?

Understanding the composition of your medication is important, particularly for patients with known allergies or intolerances to specific ingredients. Dalbavancin Baxter contains the following:

Active substance: Each vial contains 500 mg of dalbavancin (as dalbavancin hydrochloride). Dalbavancin is a semisynthetic lipoglycopeptide antibiotic derived from the natural product A-40926, which is produced by fermentation of the actinomycete Nonomuraea sp. The chemical modification involves the addition of a lipophilic side chain, which is responsible for the drug's extended half-life and enhanced antibacterial potency.

Excipients (inactive ingredients):

• Mannitol (E421): Used as a bulking agent in the lyophilized formulation to provide a stable cake structure and aid reconstitution. Mannitol is generally well tolerated and is not expected to cause adverse effects at the quantities present in this product.
• Lactose monohydrate: Used as a stabilizer. Patients with rare hereditary problems of galactose intolerance, total lactase deficiency, or glucose-galactose malabsorption should be informed that this product contains lactose, although the amount present (approximately 175 mg per vial) is unlikely to cause symptoms in most lactose-intolerant individuals.
• Hydrochloric acid: Used for pH adjustment during manufacture.
• Sodium hydroxide: Used for pH adjustment during manufacture.

After reconstitution with sterile water for injections, dalbavancin produces a clear to slightly opalescent, colorless to pale yellow solution. Before use, the reconstituted solution must be further diluted with 5% dextrose (glucose) solution to the required concentration for intravenous infusion. Dalbavancin should not be diluted with sodium chloride (normal saline) solutions, as this may cause precipitation. The reconstituted solution has a pH of approximately 3.5 to 4.5.

This medicine contains less than 1 mmol sodium (23 mg) per dose, meaning it is essentially sodium-free. This may be relevant for patients on a sodium-restricted diet.