Scientists have tested an experimental nasal spray that may protect against influenza even before the virus enters the body.
Unlike traditional vaccines, whose effectiveness heavily depends on how accurately the circulating strains are predicted, the new approach aims to block the virus right in the nose — at its main "entry point." The results of the first human trials have been published in the journal Science Translational Medicine (STM).
The development is based on the monoclonal antibody CR9114, which can recognize and neutralize almost all known variants of influenza virus A and B. The antibody is sprayed into the nasal cavity, creating local protection of the mucosa. A preliminary clinical study involved 143 healthy volunteers aged 18 to 55. Participants received the drug either once or twice a day for two weeks.
The trials showed that the spray is well tolerated and does not cause serious side effects. With twice-daily use, the antibody remained in the nose long enough and remained biologically active, effectively neutralizing the virus in laboratory tests. Moreover, the concentration of the protective substance in the mucosa was found to be thousands of times higher than when antibodies were administered through the bloodstream, even at lower doses.
The authors emphasize that this is still an early stage of research. Ahead lies the verification of how effectively the drug protects against actual infection and whether it can reduce the transmission of the virus between people.
