IVX-A12 is a vaccine designed to protect against two viruses: the Respiratory Syncytial Virus (RSV) and the Human Metapneumovirus (hMPV). These viruses can cause lung infections, especially in older adults. The vaccine works by using particles that look like the viruses to help the body recognize and fight them off if exposed in the future. This study is testing how well the vaccine works, how safe it is, and how the body responds to it in people aged 60 and older.

Respiratory Syncytial Virus Infection – Respiratory Syncytial Virus (RSV) infection is a common respiratory virus that affects the lungs and breathing passages. It typically begins with symptoms similar to a mild cold, such as a runny nose, cough, and fever. As the infection progresses, it can lead to more severe respiratory issues, especially in older adults and those with weakened immune systems. The virus can cause inflammation of the small airways in the lungs, leading to wheezing and difficulty breathing. In some cases, it can progress to bronchiolitis or pneumonia, which are more serious conditions. The infection is highly contagious and spreads through respiratory droplets.

Human Metapneumovirus Infection – Human Metapneumovirus (hMPV) infection is a respiratory virus that causes symptoms similar to those of the common cold. It often starts with a runny nose, cough, and sore throat. As the infection develops, it can lead to more severe respiratory problems, particularly in older adults and individuals with compromised immune systems. The virus can cause inflammation in the airways, resulting in wheezing and difficulty breathing. In some cases, it can lead to bronchiolitis or pneumonia, which are more severe respiratory conditions. The virus is spread through close contact with an infected person or contaminated surfaces.