Delafloxacin

Fluoroquinolones, including delafloxacin are associated with disabling and potentially long-lasting or irreversible side effects. See Fluoroquinolone antibiotics - severe adverse effects

When using fluoroquinolones:

• DO NOT prescribe for:
  • non-severe or self-limiting infections.
  • mild to moderate infections (unless other antibiotics that are commonly recommended for these infections are considered inappropriate).
• DO read the Antimicrobial Guideline section: Fluoroquinolone antibiotics - severe adverse effects
• DO ensure penicillin allergies are properly clarified and consider de-labelling in appropriate patients to avoid the use of fluoroquinolones. See guidelines: Penicillin allergy assessment and overview and Penicillin allergy challenge and delabelling
• DO ensure all patients are given the MHRA fluoroquinolone patient leaflet (this is usually given to patients with their discharge and outpatient medications).

Intravenous: 300mg bd
Oral: 450mg bd

There is no direct evidence to support use of oral delafloxacin for the initial 3 days of a treatment course. Upon initiation of delafloxacin, intravenous therapy should be used and a switch to oral treatment can be considered after approximately 3 days. 

No dose adjustment required.

Renal impairment

Oral:

• No adjustment necessary.
• Caution in severe renal impairment - monitor renal function.
• Not recommended in end stage renal disease

Intravenous:

*In patients with moderate to severe renal impairment or patients with ESRD on dialysis: Accumulation of the IV vehicle sulfobutylbetadex sodium occurs therefore serum creatinine levels should be closely monitored and if creatinine increases the use of IV delafloxacin should be discussed with Micro/ID.

Hepatic impairment

No dose adjustment necessary. 

Contraception: Woman of childbearing age MUST use effective contraception during treatment with delafloxacin

Pregnancy: AVOID. Manufacturer states that use is contraindicated. No or limited human data. Animal data has demonstrated toxicity.

Breastfeeding: AVOID. Manufacturer states that use is contraindicated. Animal data has demonstrated excretion of delafloxacin and its metabolites into breast milk.

NSAIDs: CAUTION. Taking NSAIDs at the same time as delafloxacin may induce convulsions in patients with or without a history of convulsions.

Vitamin K antagonists: anticoagulant effect enhanced-monitor INR closely and within 3-5 days of starting delafloxacin

The medications listed below reduce oral delafloxacin absorption. The oral delafloxacin SPC states takes oral delafloxacin 2 hours before or 6 hours after these medications. Consult the BNF and SPC for detailed guidance on administration:

• magnesium and aluminium antacids,
• sucralfate,
• oral zinc or iron preparations,
• oral didanosine preparations.

This is not a complete list. Please see the BNF, Summary of Product Characteristics or speak to a pharmacist.

• Delafloxacin may induce convulsions in patients with or without a history of convulsions; taking NSAIDs at the same time may also induce them.
• Delafloxacin is not recommended in patients with a known history of myasthenia gravis. Fluoroquinolones, including delafloxacin, have neuromuscular blocking activity and may exacerbate muscle weakness in patients with myasthenia gravis. 
• Use with caution in patients with G6PD deficiency or with family history of G6PD deficiency.
• 300mg IV delafloxacin contains 175 mg sodium, equivalent to 8.8% of the WHO recommended maximum daily intake of 2 g sodium for an adult.
• Cases of bullous skin reactions like Stevens-Johnson syndrome or toxic epidermal necrolysis have been reported with fluoroquinolones. Treatment should be immediately reviewed if skin and/or mucosal reactions occur.

• A. Menarini Farmaceutica Internazionale SRL. Quofenix 300 mg powder for concentrate for solution for infusion summary of product characteristics: Electronic Medicines Compendium [Internet]. Date of last revision: 22/11/23 [cited 20/1/24]. Available from: https://www.medicines.org.uk/emc/product/11481/smpc
• A. Menarini Farmaceutica Internazionale SRL. Quofenix 450 mg tablets summary of product characteristics: Electronic Medicines Compendium [Internet]. Date of last revision: 22/11/23 [cited 20/1/24]. Available from: https://www.medicines.org.uk/emc/product/11482/smpc
• National Institute for Health and Care Excellence (NICE). Antimicrobial prescribing: delafloxacin for acute bacterial skin and skin structure infections (ES32) [Internet]. 2021 [cited 2023 Dec 4]. Available from: https://www.nice.org.uk/advice/es32
• Joint Formulary Committee. British National Formulary (BNF). [cited 20/1/24]. Available from: https://www.medicinescomplete.com
• The Renal Drug Database. Delafloxacin [Internet]. Date of last revision: 31/10/23 2023 [cited  20/1/24]. Available from: https://renaldrugdatabase.com/monographs/delafloxacin
• Melinta Therapeutics, LLC. BAXDELA- delafloxacin meglumine highlights of prescribing information: Food and Drug Administration [Internet]. 2021 [cited 2023 Dec 4]. Available from: https://nctr-crs.fda.gov/fdalabel/ui/spl-summaries/criteria/404161
• Briggs GG, Freeman RK, Tower CV, Forinash AB. Drugs in pregnancy and lactation. 14 November 2023 [Internet]. 2023 [cited 2023 Dec 4]. Available from: https://www.medicinescomplete.com/  
• European Medicines Agency. Quofenix European public assessment report [Internet]. 2022 [cited 2023 Dec 4]. Available from: https://www.ema.europa.eu/en/medicines/human/EPAR/quofenix
• MHRA. Drug Safety update (January 2024) Fluoroquinolone antibiotics: must now only be prescribed when other commonly recommended antibiotics are inappropriate. Accessed HERE
• MHRA. Drug Safety update (September 2023) Fluoroquinolone antibiotics: suicidal thoughts and behaviour. Accessed HERE
• MHRA. Drug Safety update (August 2023) Fluoroquinolone antibiotics: reminder of the risk of disabling and potentially long-lasting or irreversible side effects. Accessed HERE
• MHRA. Drug Safety update (December 2020) Systemic and inhaled fluoroquinolones: small risk of heart valve regurgitation; consider other therapeutic options first in patients at risk. Accessed HERE 
• MHRA. Drug Safety update (March 2019) Fluoroquinolone antibiotics: new restrictions and precautions for use due to very rare reports of disabling and potentially long-lasting or irreversible side effects. Accessed HERE
• MHRA. Drug Safety update (November 2018) Systemic and inhaled fluoroquinolones: small increased risk of aortic aneurysm and dissection; advice for prescribing in high-risk patients. Accessed HERE