A Randomized, Double-Blind, Placebo-Controlled Phase 2/3 Study to Determine the Safety and Effectiveness of Azeliragon in the Treatment of Patients Hospitalized for Coronavirus Disease 2019 (COVID-19) or Pneumonia

Inclusion Criteria: * Patients with at least two of the following signs or symptoms: cough, chest pain, shortness of breath, hypoxia (oxygen saturation \<90%) * Clinical diagnosis of pneumonia or COVID-19 during the first 48 hours of hospitalization. * Patients admitted to the hospital within the previous 48 hours (from time of admission to initial treatment dose.) * Provide informed consent to participate in the study (by participant or legally-acceptable representative). Exclusion Criteria: * Patients for whom intubation within 24 hours of admission is considered likely. * Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) \>3x upper limit of normal (ULN), OR total serum bilirubin \>2x ULN. * Patients who were receiving dialysis as a regular treatment at the time of admission. (Participants are not excluded for historic need for dialysis.) * Chronic liver disease with Child-Pugh class B of (7 to 9) or higher. * Patients with an electrocardiogram (ECG) corrected QT interval (QTc) \> 500 ms. * Patients requiring treatment with strong inhibitors of CYP2C8 * Females of childbearing potential who are pregnant, breastfeeding, and/or not using a highly-effective method of contraception (consistent with local regulations regarding the methods of contraception for those participating in clinical studies, including willingness to use 2 acceptable forms of contraception from screening until after the end of drug treatment. Acceptable forms include tubal ligation, male latex condom with or without spermicide, partner's vasectomy, diaphragm with spermicide, intrauterine device, cervical cap/sponge with spermicide, contraceptive sponge, female condom, hormonal contraceptive including oral, transdermal, vaginal ring, subcutaneous injection, or implanted rod.) * Allergy to azeliragon or formulation excipients in the azeliragon or placebo capsule. * Concurrent participation in another device or drug trial for treatment purposes. Trials with devices intended for diagnostic purposes only are allowable.. * Any other condition, including abnormal laboratory values that, in the judgment of the investigator, could put the participant at increased risk, or would interfere with the conduct or planned analysis of the study.