EV25 is a medication being tested in this clinical trial. It is given as a spray into the nose, which is known as intranasal administration. The main goal of this study is to see if EV25 is safe and well-tolerated when given to healthy people. The trial also aims to understand how the body processes EV25 after it is administered. In the second part of the study, researchers are looking at how EV25 affects people who have been exposed to a specific type of flu virus, called influenza H3N2. They want to see if EV25 can help reduce the amount of virus in the body compared to those who do not receive the medication. This study is important to determine if EV25 could be a potential treatment for flu infections in the future.

Influenza – Influenza, commonly known as the flu, is a viral infection that primarily affects the respiratory system, including the nose, throat, and lungs. It is caused by influenza viruses, which are classified into types A, B, and C, with type A being the most common and often responsible for seasonal outbreaks. The disease typically begins suddenly with symptoms such as fever, chills, muscle aches, cough, congestion, runny nose, headaches, and fatigue. As the infection progresses, symptoms can become more severe, leading to complications such as pneumonia, especially in vulnerable populations like the elderly and those with weakened immune systems. Influenza is highly contagious and spreads through respiratory droplets when an infected person coughs, sneezes, or talks. The course of the illness usually lasts about one to two weeks, with most people recovering without requiring medical intervention.