PT - JOURNAL ARTICLE AU - Wenrui Guo AU - Linsey M Porter AU - Thomas WM Crozier AU - Matthew Coates AU - Akhilesh Jha AU - Mikel McKie AU - James A Nathan AU - Paul J Lehner AU - Edward JD Greenwood AU - Frank McCaughan TI - Topical TMPRSS2 inhibition prevents SARS-CoV-2 infection in differentiated human airway cultures AID - 10.26508/lsa.202101116 DP - 2022 Apr 01 TA - Life Science Alliance PG - e202101116 VI - 5 IP - 4 4099 - https://www.life-science-alliance.org/content/5/4/e202101116.short 4100 - https://www.life-science-alliance.org/content/5/4/e202101116.full SO - Life Sci. Alliance2022 Apr 01; 5 AB - Background: There are limited effective prophylactic/early treatments for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Viral entry requires spike protein binding to the angiotensin-converting enzyme-2 receptor and cleavage by transmembrane serine protease 2 (TMPRSS2), a cell surface serine protease. Targeting of TMPRSS2 by either androgen blockade or direct inhibition is in clinical trials in early SARS-CoV-2 infection. Methods: We used differentiated primary human airway epithelial cells at the air–liquid interface to test the impact of targeting TMPRSS2 on the prevention of SARS-CoV-2 infection. Results: We first modelled the systemic delivery of compounds. Enzalutamide, an oral androgen receptor antagonist, had no impact on SARS-CoV-2 infection. By contrast, camostat mesylate, an orally available serine protease inhibitor, blocked SARS-CoV-2 entry. However, oral camostat is rapidly metabolised in the circulation, with poor airway bioavailability. We therefore modelled local airway administration by applying camostat to the apical surface of differentiated airway cultures. We demonstrated that a brief exposure to topical camostat effectively restricts SARS-CoV-2 infection. Conclusion: These experiments demonstrate a potential therapeutic role for topical camostat for pre- or post-exposure prophylaxis of SARS-CoV-2, which can now be evaluated in a clinical trial.