Zanamivir for the treatment of clinically diagnosed influenza in clinical practice - Results of the valuable-insights-from-patients study

Background: The efficacy and tolerability of the neuraminidase inhibitor zanamivir in the treatment of influenza have been established in an extensive programme of controlled clinical trials. Objective: To extend these data by assessing patients' perceptions of zanamivir in clinical practice during the 1999 to 2000 influenza season in the USA. Design: Telephone survey of patients or clinicians with clinically diagnosed influenza who were treated with zanamivir. Patients: 26 170 patients enrolled in the study, of whom 14 328 (13 432 patients and 896 clinicians) responded to the questionnaire. Methods: Patients completed by telephone interactive voice-response a 10-item questionnaire within 5 days of finishing a 5-day course of zanamivir 10mg twice daily. Clinicians with clinically diagnosed influenza could also participate as respondents. Results: Symptoms improved within 2 days of initiation of zanamivir in 71% and 72% of patients and clinicians, respectively, and within 24 hours in 33% of patients and 31% of clinicians. Fever and body/muscle aches, rated as among the most bothersome symptoms, were the first symptoms to improve. 40% of patients and 48% of clinicians reported resumption of normal activities within 2 days of starting zanamivir; 67% of patients and 78% of clinicians resumed normal activities within 3 days. The zanamivir delivery device, Diskhaler(R), was considered somewhat or very easy to use by 91% and 87% of patients and clinicians, respectively, and the instructions somewhat or very easy to understand by 87% of patients and 83% of clinicians. The majority of patients (87%) and clinicians (93%) were somewhat or very satisfied with zanamivir, and 94% of patients and 96% of clinicians indicated that they would recommend zanamivir to a friend. Conclusions: These clinical practice data demonstrate that zanamivir is rapidly effective and quickly returns patients to normal activities. Nine of 10 patients were satisfied with zanamivir and would recommend it to a friend with influenza.