Evaluation of the efficacy and safety of riamilovir for preventing acute respiratory viral infections in young adults in organized collectives

Objective. To evaluate the efficacy and safety of the direct-acting antiviral drug riamilovir under different dosing regimens for the prevention of acute respiratory viral infections in young adults living in an organized collective setting.

Materials and methods. A prospective comparative study was conducted involving 450 male participants aged 18– 22 years. Volunteers were divided into three groups: riamilovir 500 mg/day (n=150), riamilovir 250 mg/day (n=150), and a control group without prophylaxis (n=150). The drug was administered orally for 15 days, and follow-up lasted 30 days. The incidence of acute respiratory infections, temporal distribution of cases, duration and severity of key symptoms, PCR test results, and the frequency of adverse events were assessed.

Results. During the observation period, the incidence of ARVI was 13.3% in the 500 mg group, 18.0% in the 250 mg group, and 28.7% in the control group (χ²=11.58; p=0.003). A statistically significant reduction in acute respiratory viral infections incidence was observed in the 500 mg group compared to the control (p=0.0017). Participants receiving riamilovir showed higher median cycle threshold (Ct) values (31.08 and 31.90 versus 25.68 in the control group), which may indicate lower viral loads. The drug significantly reduced the duration of fever (p=0.0079) and general infectious intoxication syndrome (p=0.047), as well as the severity of cough and intoxication (p<0.01). No adverse events were reported.

Conclusion. Riamilovir demonstrated prophylactic efficacy against acute respiratory viral infections by reducing the incidence and severity of clinical manifestations, with a favorable safety profile. The drug may be considered as a means of nonspecific pharmacological prevention of respiratory viral infections in organized collectives.

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