Recent advances in biologic therapy of asthma and the role in therapy of chronic rhinosinusitis

Great strides have been made in the last five years in understanding the pathology of chronic rhinosinusitis (CRS). CRS is now accepted to be the end-stage manifestation of inflammation resultant from various pathogenetic mechanisms. This has resulted in increasing recognition of distinct CRS endotypes. Such endotypes encompass a cluster of patients with similar pathogenic mechanisms that may have common therapeutic targets and responsiveness to interventions. The elucidation of mechanisms leading to the development of chronic upper (sino-nasal) airway inflammation has to some extent paralleled investigations of aberrant pathways operant in asthma. In this review, we focus on recent developments in understanding the innate immune pathways as well as adaptive (late) immune responses in CRS and asthma and their implication as potentially modifiable targets in CRS. Specific biologic therapy (that is, monoclonal antibodies targeting cytokines, cytokine receptors, or specific key molecules targeting inflammation) is an exciting proposition for the future of medical management of CRS. As of the writing of this article, the agents described are not approved for use in CRS; many have partial approval for use in asthma or are considered experimental.