The IN2COVID Study is a 2-staged phase I/II double-blind, randomized, placebo-controlled trial to evaluate the efficacy and safety of AP-003 (Interferon α2b) when administered via inhalation twice daily for 10 days. Participants will have a final visit at Day 11.

A lead-in phase 1 substudy will be performed with at least 18 healthy adult male subjects to assess safety and tolerability of inhaled AP-003 compared to placebo for 10 days. Two cohorts of 9 subjects will be randomly assigned to receive two doses of inhaled AP-003 or placebo with an allocation ratio of 2:1. The first cohort will assess a dose of 2.5 MIU of inhaled AP-003. If no adverse events are observed, the second cohort will be conducted using a dose of 5 MIU of inhaled AP-003. Maximum tolerated dose will be determined in this phase 1 substudy.

After the completion of phase 1, the study will continue with a phase 2 treatment RCT in patients with COVID-19. In this phase, 150 adults with mild or moderate COVID-19 demonstrated by SARS-CoV-2 positive polymerase chain reaction (PCR) ≤ 5 days at enrollment will be randomized 1:1 (75 in each arm) to receive nebulized AP-003 or identical placebo twice daily during 10 days.

Phase 1 stage:

Inclusion criteria:

1. Male subjects aged 18-50 years;
2. In good state of health, determined by medical history, physical exam, and normal laboratory tests at screening;
3. Are able to provide informed consent for participation;
4. Are able and willing to comply with the study schedule and procedures.

Exclusion Criteria

1. Active SARS-CoV-2 infection demonstrated by positive polymerase chain reaction (PCR) at enrollment;
2. Requiring CPAP for sleep apnea;
3. Pre-existing pulmonary disease;
4. Have any serious acute concomitant illness that, in the opinion of the investigator, would interfere with evaluation of safety of AP-003, or put the participant at risk of harm from study participation;
5. Are currently receiving an investigational agent, have participated in another study of an investigational agent within 30 days of enrollment, or were previously enrolled in the current study;
6. Are legally incompetent and unable to understand the study's purpose, significance, and consequences, and to make decisions accordingly;
7. Have known hypersensitivity to interferon alpha or any component of the study drug or placebo control.

Phase 2 stage:

Inclusion criteria:

1. Active SARS-CoV-2 infection demonstrated by positive polymerase chain reaction (PCR) ≤ 5 days at enrollment;
2. Symptomatic of mild or moderate COVID-19 for ≤ 5 days at enrollment. Symptoms can include fever, cough, sore throat, malaise, headache, muscle pain, gastrointestinal symptoms, chest pain, with or without shortness of breath on exertion/dyspnea;
3. Age ≥ 18 years;
4. Are able to provide informed consent for participation;
5. Are able and willing to comply with the study schedule and procedures.

Exclusion Criteria

1. Patients requiring CPAP for sleep apnea.
2. Patients with pre-existing pulmonary disease requiring chronic O2 supplementation.
3. Patients with known infection with Influenza A or B;
4. In the opinion of the Investigator, should undergo ventilatory (CPAP, mechanical ventilation, etc.) or circulatory support within 24 hours of study enrollment;
5. Have any serious acute concomitant illness that, in the opinion of the Investigator, would interfere with evaluation of safety or efficacy, or put the participant at risk of harm from study participation;
6. Are currently receiving an investigational agent, have participated in another study of an investigational agent within 30 days of enrollment, or were previously enrolled in the current study;
7. Are legally incompetent and unable to understand the study's purpose, significance, and consequences, and to make decisions accordingly;
8. Women who are pregnant or breast-feeding, or planning to conceive in the next 30 days;
9. Have known hypersensitivity to interferon alpha or any component of the study drug or placebo control.

Available upon reasonable request.

Data will become available 1 year after study completion during 5 years upon reasonable request.

Available upon reasonable request.