Finafloxacin: New fluoroquinolone for acute otitis externa


New Drug: Finafloxin

Finafloxacin (Xtoro—Alcon Laboratories) 0.3% otic suspension has been FDA approved for the treatment of acute otitis externa caused by susceptible strains of Pseudomonas aeruginosa and Staphylococcus aureus. Commonly referred to as swimmer’s ear, acute otitis externa is an infection of the outer ear canal typically caused by bacteria in the ear canal. The most common pathogens causing this infection are P. aeruginosa (20%−60%) and S. aureus (10%−70%), often occurring as a polymicrobial infection. 


The approval of finafloxacin adds to the number of antimicrobial drugs indicated for this condition. “The availability of multiple treatment options allows physicians and patients to find the treatment to meet their needs,” said Edward Cox, MD, MPH, Director of the Office of Antimicrobial Products in FDA’s Center for Drug Evaluation and Research, in an FDA news release. 


Practice guidelines 


In February 2014, the American Academy of Otolaryngology−Head and Neck Surgery Foundation published practice guidelines for the management of acute otitis externa. The primary purpose of this guideline was to promote appropriate use of oral and topical antimicrobials and highlight the need for adequate pain relief in patients 2 years of age and older. The guidelines include eight key action statements that emphasize proper diagnosis, treatment, patient education, and follow-up. 


Analgesic treatments are recommended for pain control and should be tailored to the severity of pain reported by patients. Topical antimicrobials are recommended as the drugs of choice for initial therapy of diffuse, uncomplicated acute otitis externa (e.g., acetic acid, acetic acid/hydrocortisone, ciprofloxacin/hydrocortisone, ciprofloxacin/dexamethasone, neomycin/polymyxin B/hydrocortisone, ofloxacin), and systemic antimicrobials should not be used as initial therapy unless there is extension outside the ear canal or the presence of specific host factors that would indicate systemic therapy is needed. The guidelines also include a detailed table on instructions that should be given to patients on how to properly administer prescribed ear drops. Reassessment of patients who fail to respond to initial therapy is also advised within 48 to 72 hours. 


Clinical data 


Data from two randomized, multicenter trials involving 1,234 patients aged 6 months to 85 years with acute otitis externa, including 560 patients who were pathogen positive for P. aeruginosa and/or S. aureus, showed that use of finafloxacin was superior to placebo for both clinical and microbiological outcomes, as well as time to cessation of ear pain. 


In the pathogen-positive group, clinical cure on day 11 was 71% in the finafloxacin group compared with 37% in the placebo group, and the median time to cessation of ear pain in this group was 3.5 days for active treatment versus 6.8 days for placebo. Microbiological success, defined as eradication of all baseline organisms, on day 11 was achieved by 67% of patients in the finafloxacin group compared with 13% of those in the placebo group. 


Similar results for clinical outcomes and cessation of ear pain were seen in the intention to treat population (n = 1,234) for finafloxacin compared with placebo (71% vs. 50% clinical cures; 3.5 d vs. 5.3 d for cessation of ear pain, respectively). Of the 618 patients who were treated with active drug in these two studies, the most commonly reported adverse events, occurring in 1% of patients, were ear pruritus and nausea.


Patient counseling


Counsel patients on proper dosage and administration and potential adverse events. Advise patients to shake the bottle well before use and warm the suspension by holding the bottle in their hand for 1 to 2 minutes before dosing to avoid dizziness, which may occur from administration of a cold suspension. Instruct patients to lie with the affected ear upward, instill the drops, and maintain the position for 60 seconds to aid in the penetration of the drops into the ear canal. Inform patients that itching of the ear and nausea were the most common adverse effects reported with use of the suspension and that rash may occur in those allergic to the drug or this class of drugs (i.e., quinolones).


Finafloxacin (Xtoro)


Manufacturer: Alcon Laboratories 


Drug class: Fluoroquinolone antimicrobial

Indication: Treatment of acute otitis externa caused by susceptible strains of Pseudomonas aeruginosa and Staphylococcus aureus in patients 1 year and older

Dosage: Four drops into the affected ear(s) twice daily for 7 days 


  • For patients who require an otowick, the initial dose can be doubled to eight drops, followed by four drops into the affected ear(s) twice daily for 7 days. Instruct patients on proper administration as noted in the patient counseling section.

  • Allergic reactions to finafloxacin may occur in patients with a history of hypersensitivity to this agent or other quinolones; discontinue treatment and use an alternative therapy.

Of note: Prolonged use may result in overgrowth of nonsusceptible organisms, including yeast and fungi. Use should be stopped if this occurs, and an alternative therapy should be initiated.


Reference


Otolaryngol Head Neck Surg. 2014;150(1 Suppl):S1−S24.