N-acetylneuraminic acid compositions and methods of use

A method for inhibiting or treating an upper respiratory tract viral infection of a human subject suffering from or at risk of such an infection, said method comprising:

• intranasally administering via a pump spray device an aqueous spray formulation consisting of N-acetylneuraminic acid (NANA) as the active agent in a dosage of from 0.1 to 5.0 mg of NANA and physiologically acceptable carriers or excipients selected from the group consisting of water, saline, vitamins, minerals, colorants, propellants, anti-oxidants, preservatives, fillers, emulsifiers, suspending agents, dispersing agents, wetting agents, iso-osmotic agents and thixotropic agents, to each nostril of the subject suffering from or at risk of said upper respiratory tract viral infection under conditions such that said upper respiratory tract infection is inhibited or treated;
• wherein the pH of the aqueous formulation is from 2.8 to 3.2 and wherein said upper respiratory tract infection is selected from the group consisting of common colds and rhinovirus infection.