Personalized small molecule therapy for severe asthma and cystic fibrosis.

Respiratory infection with COVID-19 (the SARS-CoV-2 virus) has become pandemic. It has significant mortalityand high morbidity, particularly among older patients. Death typically results from severe respiratory infectionleading to ARDS. To bind to cell membranes, SARS-CoV-2 requires S protein cleavage either by thetransmembrane serine protease, serine 2 (TMPRSS2), or by the cathepsin B and L (CatB/L) endosomalcomplex. TMPRSS2 can be inhibited by camostat methylate (CM), but CM is an irritant and may not be ideal forairway administration in patients with evolving ARDS. Of note, CatB/L is inhibited by endosomal alkalinizationusing ammonium chloride. As part of P01 project HL128192, we are studying the beneficial effects of airwayalkalinization in patients with asthma and cystic fibrosis. We have a drug, alkaline glycine buffer (AGB), that isbeing produced for inhalation in our P01 project. This drug has an active IND and has excellent safety data. Wetherefore tested to determine whether AGB would cause intracellular alkalinization in cultured primary humanairway epithelial cells obtained from our P01 subjects. It did; and the drug was well-tolerated by the cells in vitro(as it is in vivo). The next step is to determine whether AGB inhibits viral replication (plaque formation as afunction of multiplicity of infection [MOI]) and viral entry (PCR) in our primary human airway epithelial cultures.To do this, we are partnering with our Indiana University BSL3 virology lab (Dr.'s Gilk and Robinson) whoanticipate delivery of SARS-CoV-2 next week. Their lab has completed preparation, particularly in anticipationof this project. If in fact AGB inhibits viral replication, we would propose to discuss with the FDA the possibilitythat we could expand our IND, allowing a trial in patients at risk for respiratory distress associated with knownCOVID-2 respiratory disease. Ultimately, outcomes of this trial would be proposed to include: mortality (primary);as well as ICU length of stay and oxygen saturation index area under the curve (secondary). In the studyproposed here, we plan to accomplish three Aims. First we will test the hypothesis that SARS-CoV-2 S-proteincleavage is inhibited by human primary airway epithelial cell alkalinization using AGB. Second, we will test thehypothesis that AGB exposure prevents SARS-CoV-2 replication and cell entry in primary human airwayepithelial cells in vitro. Third, we will perform dose-response and time course experiments to determine whetherthe inhibition of SARS-CoV-2 replication and cell entry using AGB could be a realistic therapy.