Home Diseases Respiratory Syncytial Virus (RSV)

RSV is a common infection of the lungs and breathing passages

There are no specific RSV antiviral treatments licensed for widespread use in the treatment of seasonal RSV infection.

Epidemiology of severe RSV infection

RSV occurs during cold seasons

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Respiratory Syncytial Virus

Pulmonary Aspergillosis

Young Children

In young children under the age of 2 years, RSV is the most common cause of bronchiolitis and pneumonia. Indeed, it’s estimated that up to 90% of childhood bronchiolitis is caused by RSV. More than half of all children will be infected by their first birthday, and by two years of age essentially all children have experienced RSV infection. Patients with underlying conditions can develop serious complications.

Baby 0K+

Each year, more than 120,000 infants in the US are hospitalized for RSV


In the elderly, RSV is a significant cause of morbidity. Epidemiological evidence indicates the impact of RSV in older adults may be similar to non-pandemic influenza.

Elderly people 0K

RSV accounts for up to 14,000 deaths in people over 65 years in the US every year


In immunocompromised patients (patients undergoing bone marrow transplant, graft vs host disease and solid-organ transplant – especially lung transplant), RSV results in significant morbidity and mortality. Transplant patients with RSV infection often have delayed engraftment or graft failure, and the infection can progress to respiratory failure and/or bronchiolitis obliterans.


RSV is the leading cause of severe infections in severely immunocompromised patients, with mortality rates as high as 80%

There are currently no specific antiviral treatments for RSV

There are no specific RSV antiviral treatments licensed for widespread use in the treatment of seasonal RSV infection. Many factors contribute to the difficulty in treating the disease; most importantly the high levels of RSV replication in the bronchial epithelium, which is hard to reach with systemic (oral) therapies.

The barrier to the systemic treatment of RSV can be overcome by delivery of potent antiviral treatments directly to the site of action in the lung. Low-dose administration (typically 100ug–2mg) with minimal systemic exposure is associated with improved safety and tolerability. This is critical for treatment success in infants with RSV bronchiolitis where safety is paramount. Another important consideration is the selection of target class to avoid the emergence of antiviral resistance.