The recommended dose of Quinsair is 240mg by inhalation twice daily in alternating cycles of 28 days on treatment followed by 28 days off treatment. This can be continued for as long as the patient is obtaining clinical benefit.
The inhalation ampoules are supplied with a Zirela Nebuliser Handset. Quinsair should be inhaled over 5 minutes using the Zirela handset and a Zirela Aerosol Head connected to an eBase Controller or an eFlow rapid Control Unit.
If acute bronchospasm occurs after inhaling Quinsair, use of a short-acting inhaled bronchodilator between 15 minutes and 4 hours prior to subsequent doses may be of benefit.
The safety and efficacy of levofloxacin inhalation solution were compared with those of tobramycin inhalation solution in a phase III, open label, randomised trial involving 282 patients with stable CF and chronic P. aeruginosa infection. The primary endpoint was Day 28 FEV1 % predicted relative change.
Levofloxacin was found to be non-inferior to tobramycin with a least squares mean between-group difference in FEV1 of 1.86% (95% CI -0.66 to 4.39%).
The time to first exacerbation was not significantly different between the two treatment groups. Patients receiving levofloxacin had a median time to first exacerbation of 131 days, compared with 90.5 days in the tobramycin group (HR 0.78; 95% CI 0.57 to 1.07, p=0.15).
The proportion of patients hospitalised for a respiratory exacerbation over the 168-day study period was significantly lower in the levofloxacin group than in the tobramycin group (17.5% vs 28.0%, p=0.04).
Another study assessed the efficacy and safety of inhaled levofloxacin in heavily treated CF patients with P. aeruginosa infection. A total of 151 patients were randomised to receive levofloxacin 120mg daily (n=38), 240mg daily (n=37), 240mg twice daily (n=39) or placebo (n=37) for 28 days.
Adjusted mean sputum P. aeruginosa density decreased from baseline to day 28 for patients receiving levofloxacin, but increased for placebo-treated patients. At day 28, the greatest treatment effect was observed in the levofloxacin 240mg twice-daily group (p=0.001). A greater proportion of patients in the levofloxacin treatment groups experienced a greater than 10% increase in adjusted FEV1 on day 28 compared with the placebo group (59%, 54% and 72% for levofloxacin 120mg daily, 240mg daily and 240mg twice daily, respectively, vs 27% for placebo).
Levofloxacin was well tolerated in trials with the most commonly reported adverse effects being cough (54%), dysgeusia (30%) and fatigue/asthenia (25%).