Efficacy of Proxalutamide (GT0918) in Hospitalized COVID-19 Patients

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infectivity is mediated by the androgen-promoted protease, transmembrane protease, serine 2 (TMPRSS2). Previously, we have shown that treatment with proxalutamide, a non-steroidal androgen receptor antagonist, accelerates viral clearance and clinical remission in outpatients with coronavirus disease 2019 (COVID-19) compared to placebo. The effects in hospitalized COVID-19 patients were unknown. Methods: Men and women hospitalized but not requiring mechanical ventilation were randomized (1:1 ratio) to receive 300 mg of proxalutamide per day or placebo for 14 days. The study was conducted at eight sites in the state of Amazonas, Brazil. The primary outcome measure was the clinical status (8-point ordinal scale) at 14-days post-randomization. The primary efficacy endpoint was the 14-day recovery ratio (alive hospital discharge [scores 1, 2]). Findings: A total of 645 patients were randomized (317 received proxalutamide, 328 placebo) and underwent intention-to-treat analysis. The 14-day median ordinal scale score in the proxalutamide group was 1 (interquartile range [IQR]=1–2) versus 7 (IQR=2–8) for placebo, P<0.001. The 14-day recovery rate was 81.4% for proxalutamide and 35.7% for placebo (recovery ratio, 2.28; 95% CI 1.95–2.66 [P<0.001]). The 28-day all-cause mortality rate was 11.0% for proxalutamide versus 49.4% for placebo (hazard ratio, 0.16; 95% CI 0.11–0.24). The median post-randomization time to recovery was 5 days (IQR=3–8) for proxalutamide versus 10 days (IQR=6–15) for placebo.Interpretation: Hospitalized COVID-19 patients not requiring mechanical ventilation receiving proxalutamide had a 128% higher recovery rate than those treated with placebo. Clinical Trial Registration Details: ClinicalTrials.gov number, NCT04728802Funding Information: Kintor Pharmaceuticals, Ltd.Declaration of Interests: Kintor Pharmaceuticals, Ltd. manufactures and plans to market proxalutamide, and has an investigational new drug (IND) application under United States Food and Drugs Administration to conduct a Phase 3 study for proxalutamide for COVID19. Applied Biology, Inc. has patents pending regarding antiandrogen therapy for COVID19. Dr. Goren, Dr. McCoy, and Dr. Li are employees of Applied Biology, Inc. Dr. Cadegiani has served as a clinical director for Applied Biology, Inc. Dr. Wambier has served as an advisor to Applied Biology, Inc. The other authors have no conflict of interest to declare.Ethics Approval Statement: The study was approved by an ethics committee and registered in clinicaltrials.gov (NCT04728802), and also approved by Brazilian National Ethics Committee, approval number 4.513.425; CAAE 41909121.0.0000.5553; Comitê de Ética em Pesquisa (CEP) of the Comitê Nacional de Ética em Pesquisa (CONEP) of the Ministry of Health (MS). (CEP/CONEP/MS).