This study is an adaptive, randomized, double-blind, placebo-controlled trial to evaluate the safety and efficacy of novel therapeutic agents in hospitalized adult patients adults diagnosed with COVID-19. The study is a multicenter trial that will be conducted in up to 50 approximately 100 sites globally. The study will be a series of 2-arm comparisons between compare different investigational therapeutic agents and to a placebo control arm. There will be interim monitoring to introduce new arms and allow early stopping for futility, efficacy, or safety. If one therapy proves to be efficacious, then this treatment will then may become the control arm for comparison(s) with new experimental treatment(s). Any such change would be accompanied by an updated sample size. Because of the possibility that background standards of supportive care may evolve/improve over time as more is learned about successful management of COVID-19, comparisons of safety and efficacy will be based on data from concurrently randomized participants subjects. An independent data Data and safety monitoring board Safety Monitoring Board (DSMB) will actively monitor interim data to make recommendations about early study closure or changes to study arms . Randomization will be stratified by: 1) site and 2) severity of illness at enrollment, severe disease (requiring mechanical ventilation or oxygen, a SpO2 </= 94% or tachypnea (respiratory rate >/= 24 breaths/min)) or mild-moderate disease (SpO2 > 94% and respiratory rate < 24 breaths/min without supplemental oxygen)). Subjects will be assessed daily while hospitalized. Discharged patients will be asked to attend study visits at Days 15, and 29. All subjects will undergo a series of efficacy, safety, and laboratory assessments. The primary objective of the study is to evaluate the clinical efficacy of different investigational therapeutics relative to the control arm in patients hospitalized with COVID-19. The secondary objectives of the study are to 1) evaluate the clinical efficacy of different investigational therapeutics as compared to the control arm as assessed by clinical severity, hospitalization, and mortality, and 2) evaluate the safety of the intervention through 28 days of follow-up as compared to the control arm .

The initial sample size is projected to be 572 subjects to achieve 400 subjects with a "recovered" status (per the primary objective). The primary analysis will be based on those subjects enrolled in order to 400 recoveries. An additional analysis of the moderate severity subgroup (those with baseline status of "Hospitalized, requiring supplemental oxygen" or "Hospitalized, not requiring supplemental oxygen - requiring ongoing medical care") is also of public health importance. Hence, enrollment will be permitted until the date of April 20, 2020 to ensure 400 recoveries and provide additional data about this important subgroup. With recent enrollment rates, the total sample size may be 600 to over 800.

Subjects will be assessed daily while hospitalized. If the subjects are discharged from the hospital, they will have a study visit at Days 15, 22, and 29 as an outpatient. For discharged subjects, it is preferred that the Day 15 and 29 visits are in person to obtain safety laboratory tests and OP swab and blood (serum only) samples for secondary research as well as clinical outcome data. However, infection control or other restrictions may limit the ability of the subject to return to the clinic. In this case, Day 15 and 29 visits may be conducted by phone, and only clinical data will be obtained. The Day 22 visit does not have laboratory tests or collection of samples and may also be conducted by phone.

All subjects will undergo a series of efficacy, safety, and laboratory assessments. Safety laboratory tests and blood (serum and plasma) research samples and oropharyngeal (OP) swabs will be obtained on Days 1 (prior to infusion) and Days 3, 5, 8, and 11 (while hospitalized). OP swabs and blood (serum only) plus safety laboratory tests will be collected on Day 15 and 29 (if the subject attends an in-person visit or are still hospitalized).

The primary outcome is time to recovery by Day 29. A key secondary outcome evaluates treatment-related improvements in the 8-point ordinal scale at Day 15. As little is known about the clinical course of COVID-19, a pilot study will be used for a blinded sample size reassessment.

Grade 3 AEs are defined as events that interrupt usual activities of daily living, or significantly affects clinical status, or may require intensive therapeutic intervention. Severe events are usually incapacitating.

Grade 4 AEs are defined as events that are potentially life threatening.

Inclusion Criteria:

1. Admitted to a hospital with symptoms suggestive of COVID-19 infection.
2. Subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures.
3. Understands Subject (or legally authorized representative) understands and agrees to comply with planned study procedures.
4. Agrees to the collection of oropharyngeal (OP) swabs and venous blood per protocol.
5. Male or non-pregnant female adult >/= > / = 18 years of age at time of enrollment.
6. Has laboratory-confirmed SARS-CoV-2 infection as determined by polymerase chain reaction (PCR) or other commercial or public health assay in any specimen, as documented by either or the following:
   • PCR positive in sample collected < 72 hours prior to randomization; OR
   • PCR positive in sample collected >/= 72 hours prior to randomization, documented inability to obtain a repeat sample (e.g. due to lack of testing supplies, limited testing capacity, results taking >24 hours, etc.) AND progressive disease suggestive of ongoing SARS-CoV-2 infection.
7. Has laboratory-confirmed novel coronavirus (SARS-CoV-2) infection as determined by polymerase chain reaction (PCR), or other commercial or public health assay in any specimen < 72 hours prior to randomization.
8. Illness of any duration, and at least one of the following:
   • Radiographic infiltrates by imaging (chest x-ray, CT scan, etc.), OR
   • Clinical assessment (evidence of rales/crackles on exam) AND SpO2 </= 94% on room air, OR SpO2 < / = 94% on room air, OR
   • Requiring mechanical ventilation and/or supplemental oxygen . , OR
   • Requiring mechanical ventilation.
9. Women of childbearing potential must agree to either abstinence or use at least one primary form of contraception for not including hormonal contraception from the duration time of the study (acceptable methods will be determined by the site). screening through Day 29.
10. Agrees to not participate in another clinical trial for the treatment of COVID-19 or SARS-CoV-2 through Day 29.

Exclusion Criteria:

1. Alanine transaminase/aspartate transaminase Transaminase (ALT / ) or Aspartate Transaminase (AST) > 5 times the upper limit of normal.
2. Stage 4 severe chronic kidney disease or requiring dialysis (i.e. estimated glomerular filtration rate (eGFR) < 30) Estimated glomerular filtration rate (eGFR) < 30 ml/min (including patients receiving hemodialysis or hemofiltration).
3. Pregnancy or breast feeding.
4. Anticipated discharge from the hospital or transfer to another hospital which is not a study site within 72 hours.
5. Allergy to any study medication.