HRV belongs to a diverse family of plus-strand RNA viruses referred to as picornaviridiae, which also include the human enteroviruses and hepatoviruses (human hepatitis A), as well as certain animal viruses. There are currently three human rhinovirus (HRV) species: A, B and C, which together with the closely related enterovirus species, form the genus enterovirus. These viruses are responsible for human diseases ranging from mild respiratory tract infections (the common cold) to paralytic poliomyelitis. While more than 200 different viruses are known to cause symptoms of the common cold, it is estimated that HRV causes 30%-50% of all cases.
HRV infection is also associated with more serious conditions, including acute otitis media, sinusitis and lower respiratory tract diseases such as pneumonia, bronchitis and bronchiolitis and exacerbation of chronic respiratory illnesses. Individuals with chronic lung diseases, such as asthma and chronic obstructive pulmonary disease (“COPD”), are especially vulnerable to HRV infections, which may cause acute exacerbations of asthma, emphysema or chronic bronchitis in these more susceptible individuals and require hospitalization. Epidemiological studies have also demonstrated that a significant number of pulmonary exacerbations of cystic fibrosis (“CF”) are preceded by HRV infections. HRV is believed to be a primary cause of asthma exacerbations.
There is currently no effective treatment for infections caused by HRV. We believe successfully developing a treatment for these infections can address an important and unmet medical need.