SARS-CoV-2 induces acute neurological signs while Calcitonin Gene-Related Peptide (CGRP) signaling blockade reduces interleukin 6 (IL-6) release and weight loss in mouse models (preprint)

COVID-19 can result in neurological symptoms such as fever, headache, dizziness, and nausea. We evaluated whether the Calcitonin Gene-Related Peptide (CGRP) receptor antagonist, olcegepant, used in migraine treatment could mitigate acute neuroinflammatory and neurological responses to SARS-COV-2 infection. We infected wildtype C57BL/6J and 129/SvEv mice, and a 129 CGRP-null mouse line with a mouse-adapted SARS-CoV-2 virus, and evaluated the effect of CGRP receptor antagonism on the outcome of that infection. We determined that CGRP receptor antagonism provided protection from permanent weight loss in older (>12 m) C57BL/6J and 129 SvEv mice. We also observed acute fever and motion-induced dizziness in all older mice, regardless of treatment. However, in both wildtype mouse lines, CGRP antagonism reduced acute interleukin 6 (IL-6) levels by half, with virtually no IL-6 release in mice lacking CGRP. These findings suggest that blockage of CGRP signaling protects against acute IL-6 release and subsequent inflammatory events after SARS-CoV-2 infection.

A novel highly potent inhibitor of TMPRSS2-like proteases blocks SARS-CoV-2 variants of concern and is broadly protective against infection and mortality in mice (preprint)

The COVID-19 pandemic caused by the SARS-CoV-2 virus remains a global public health crisis. Although widespread vaccination campaigns are underway, their efficacy is reduced against emerging variants of concern (VOCs). Development of host-directed therapeutics and prophylactics could limit such resistance and offer urgently needed protection against VOCs. Attractive pharmacological targets to impede viral entry include type-II transmembrane serine proteases (TTSPs), such as TMPRSS2, whose essential role in the virus lifecycle is responsible for the cleavage and priming of the viral spike protein. Here, we identify and characterize a small-molecule compound, N-0385, as the most potent inhibitor of TMPRSS2 reported to date. N-0385 exhibited low nanomolar potency and a selectivity index of > 1 million at inhibiting SARS-CoV-2 infection in human lung cells and in donor-derived colonoids. Importantly, N-0385 acted as a broad-spectrum coronavirus inhibitor of two SARS-CoV-2 VOCs, B.1.1.7 and B.1.351. Strikingly, single daily intranasal administration of N-0385 early in infection significantly improved weight loss and clinical outcomes, and yielded 100% survival in the severe K18-human ACE2 transgenic mouse model of SARS-CoV-2 disease. This demonstrates that TTSP-mediated proteolytic maturation of spike is critical for SARS-CoV-2 infection in vivo and suggests that N-0385 provides a novel effective early treatment option against COVID-19 and emerging SARS-CoV-2 VOCs.