Key Inclusion Criteria:  Participant is admitted to hospital and has a positive severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) test by standard reverse transcription-polymerase chain reaction (RT-PCR) assay or equivalent test Participant has the presence of any symptom(s) suggestive of moderate or severe systemic illness with COVID-19  Key Exclusion Criteria:  Participant, in opinion of the investigator, is not likely to survive >=48 hours beyond Day 1 Participant has a diagnosis of asymptomatic COVID-19, mild COVID-19, or critical COVID-19 on Day 1 Participant has a documented medical history of infection with hepatitis A, B, C, or with human immunodeficiency virus (with a detectable viral load and CD4 count <500 cells per micro liter), or a documented active infection with tuberculosis. The Participant has clinically significant electrocardiogram (ECG) abnormalities at screening  Other protocol defined inclusion/exclusion criteria may apply