Abstract 711: Repurposing 2nd generation androgen receptor antagonist Proxalutamide to treat COVID-19

Abstract To date, as of 17 November 2020, there have been 55 million confirmed cases of COVID-19, including 1,4 million deaths globally, as reported to WHO. It is, therefore, very critical to discovery and development of the available treatment options for COVID-19. We here discuss the repurposing 2nd generation androgen receptor antagonist Proxalutaminde to treat COVID19. We analyzed the gender disparity of disease severity and progression in 1339 patients with COVID-19 and investigated the mechanism of gender disparity in male vs female patients with COVID 19. As androgen-androgen receptor pathway may contribute to the difference in severity and disease progression in male and female patients with COVID-19, we used cell lines derived from lung, prostate cancer and normal lung epithelial cells to determine the effect of androgen and androgen receptor antagonist Proxalutamide on the expression of two key proteins for SARS-CoV-2 to infect and enter the host cells. Angiotensin converting enzyme 2 (ACE2), a host transmembrane protein provides the binding sites for SARS-CoV-2 on the host cell surface, transmembrane protease serine 2 (TMPRSS2), a cellular serine protease, prims the S protein of SARS-Cov-2 to facilitate the viral entry into the host cells. As cytokine store plays a major role in the disease progression of COVID-19, we examined the effect of GT0918 on inducible nitric oxide synthase (iNOS) and Tumor necrosis factor-alpha (TNF-α), the macrophage polarization/activation markers, in mouse macrophage cells. In this study, we demonstrated higher rates of disease progression and mortality of male COVID-19 patients than female patients. Furthermore, we revealed that androgen-AR activation induced the expression of ACE2 and TMPRSS2 under the androgen-dependent condition in cells derived from prostate and lung cancer, which was inhibited by the blockage of AR signaling with Proxalutamide. Importantly, Proxalutamide also inhibited the expression of iNOS and TNF-α, the biomarkers for macrophage polarization/activation. These results support the role of androgen-AR signaling in the disease progression and mortality in male patients with COVID-19. We are currently conducting clinical study in COVID-19 patients with Proxalutamide in Brazil (NCT04446429). Citation Format: Liandong Ma, Youzhi Tong, Qiang Guo, Yifeng Zhou, Qianxiang Zhou, Honghua Yan. Repurposing 2nd generation androgen receptor antagonist Proxalutamide to treat COVID-19 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 711.