Randomized Controlled Parallel-Design Clinical Study of the Efficacy and Safety of Intranasal Interferon gamma in Treatment of Influenza-Like Infections

Abstract

Background: Influenza is a highly variable infection that can cause fatal complications. Universal approaches, such as general stimulation of the immune system to activate its natural antiviral capacities, seem to be a rational measure. Methods: A total of 410 patients with influenza-like infections (ILI) were randomly assigned to one of three treatment groups and one control group. Interferon gamma (IFN-γ) was administered by intranasal introduction of 1 to 3 drops into each nostril 5 times per day daily for 5 days. The first dose of investigational medicine was given within 48h of the onset of the influenza-like symptoms. One drop of the solution contains 1,000 IU of active substance. All patients received basic complex therapy without any antiviral or immunomodulating agents. The patients were followed up for 7 days. Treatment efficacy was evaluated by the mean duration of symptoms (MDS), the period of viral antigen detection (VAD) measured after 1-2 and 4-5 days of treatment, and the incidence of complications. We used conventional indicators to evaluate the safety of IFN-γ in the treatment of ILI. Results: The administration of 2 or 3 drops of IFN-γ in each nasal passage led to better outcomes manifested in the considerable (P<0.05) reduction of all acute respiratory symptoms, and therefore to a more rapid recovery. In these treatment groups, statistically significant decreases for MDS values, VAD period, and incidence of complications were registered. Intranasal IFN-γ in complex therapy of ILI was considered to be well tolerated and safe