Study halted prematurely and will not resume; participants are no longer being examined or receiving intervention.

This is a phase 1b, randomized, blinded, placebo-controlled study in adult subjects with COVID-19. This clinical trial is designed to assess the safety and immunostimulatory activity of N-803.

Inclusion Criteria

1. Age ≥ 18 years old.

2. Able to understand and provide a signed informed consent that fulfills the relevant Institutional Review Board (IRB) or Independent Ethics Committee (IEC) guidelines.

3. Has laboratory-confirmed positive novel coronavirus (SARS-CoV-2) test, as determined by polymerase chain reaction (PCR), or other commercial or public health assay in any specimen < 72 hours prior to enrollment, or meets the criteria to guide the evaluation and testing of patients under investigation (PUI) for COVID-19 (https://emergency.cdc.gov/han/2020/HAN00428.asp).

4. Has a confirmed NEW score of 0-5.

5. Has at least one of the following high-risk factors associated with a higher risk of COVID-19 progression:

   1. Age ≥ 60 years.
   2. Hypertension currently managed by at least 1 antihypertensive medication.
   3. Type 1 or 2 diabetes.
   4. Chronic obstructive pulmonary disease (COPD) diagnosed per medical history.

6. Adequate respiratory and heart function, evidenced by the following laboratory results:

   1. Respiratory rate (RR) < 20 breaths per minute (bpm).
   2. Heart rate (HR) < 90 beats per minute (bpm).
   3. Arterial oxygen saturation (SaO2) > 93% on room air.

7. Agrees to the collection of nasopharyngeal (NP) swabs and venous blood per protocol.

8. Ability to participate in required study visits and participate in adequate follow-up, as required by this protocol.

9. Agreement to practice effective contraception for female subjects of child-bearing potential and non-sterile males. Female subjects of child-bearing potential must agree to use effective contraception while on study and for at least 1 month after the last dose of N-803. Non-sterile male subjects must agree to use a condom while on study and for up to 1 month after the last dose of N-803. Effective contraception includes surgical sterilization (eg, vasectomy, tubal ligation), two forms of barrier methods (eg, condom, diaphragm) used with spermicide, intrauterine devices (IUDs), oral contraceptives, and abstinence.

Exclusion Criteria:

1. Shortness of breath or hypoxia defined by a ratio of partial pressure of arterial oxygen to the percentage of inspired oxygen (PaO2/FiO2) ≤ 300 mmHg or signs of serious lower airway disease.
2. Signs or symptoms of acute respiratory distress syndrome (ARDS), systemic inflammatory response syndrome (SIRS)/shock, or cardiac failure; or need for supplemental oxygen.
3. Inflammatory markers (C-reactive protein [CRP], lactate dehydrogenase [LDH], d-dimer, ferritin, and IL-6) > 1.5 × upper limit of normal (ULN).
4. Assessed by the Investigator to be unable or unwilling to comply with the requirements of the protocol.
5. Pregnant and nursing women. A negative serum or urine pregnancy test during screening prior to the first dose must be documented before N-803 is administered to a female subject of child-bearing potential.

No subjects were enrolled in the Placebo arm.

The planned follow up time was 29 days post dose, but the one participant enrolled was lost to follow up 3 days post dose.

The subject was on study for 3 days and lost to follow up. No adverse events were reported within those 3 days. No other subjects were enrolled.

The study is terminated early due to low enrollment. Effect of the study drug on efficacy was not analyzed.