Study Design This is a phase 1, randomized, Vehicle-controlled, double-blinded study to assess the safety of Caregen Intranasal CG-SpikeDown in healthy subjects.

All randomized subjects will receive an active drug or Vehicle. Subjects randomized to the DP(Drug product) active treatment will receive CG- SpikeDown intranasally once daily for one or seven days at either a low (25 mg) or planned (50 mg) dose.

Subject recruitment will be conducted via study advertisement on social media, and subjects will be adequately compensated. The subjects will arrive each day at the clinic to receive the treatment and will be hospitalized for safety monitoring for the first 24 hours post-DP or vehicle administration.

This is a phase 1, Randomized, Double-blinded, Vehicle-controlled, Single and Multi-Dose, Dose Escalation Study, which will assess the safety of the Caregen CG-SpikeDown drug self-administered intranasally, for healthy subjects.

The study will include 16 healthy subjects and will be conducted in a clinic under complete supervision of the clinical team. The study will start with evaluation of the lowest dose, that will be increased gradually as long as no safety issues arise.

At the first stage of the study, three (3) subjects will be randomized in a 1:2 ratio to receive vehicle treatment or the active drug, respectively. Each of the 3 subjects will receive a single 25 mg dose of the assigned treatment. These subjects will be referred as Cohort 1. If no safety issues arise, the study will proceed simultaneously to the second and third stages, as depicted in Figure 1 Study Flow Chart.

At the second stage of the study, additional three (3) subjects will be enrolled and randomized in a 1:2 ratio to receive vehicle treatment or the active drug, respectively. Each of the 3 subjects will receive a single 50 mg dose of the assigned treatment. These subjects will be referred as Cohort 2. If no safety issues arise, the study will proceed to the 4th stage.

At the third stage of the study, additional three (5) subjects will be enrolled. The first 2 subjects (out of the 5 subjects) will receive an open label DP treatment-a daily 25 mg dose for 7 days. The open-label subjects will undergo PK assessments as described in the SOA. The next 3 subjects will be randomized in a 1:2 ratio to receive vehicle treatment or the active drug, respectively. Each of the 3 subjects will receive a daily 25 mg dose of the assigned treatment for 7 days. These subjects will be referred as Cohort 3.

At the fourth stage of the study, additional three (5) subjects will be enrolled. The first 2 subjects (out of the 5 subjects) will receive an open label DP treatment-a daily 50 mg dose for 7 days. The open-label subjects will undergo PK assessments as described in the SOA. The next 3 subjects will be randomized in a 1:2 ratio to receive vehicle treatment or the active drug, respectively. Each of the 3 subjects will receive a daily 50 mg dose of the assigned treatment for 7 days. These subjects will be referred as Cohort 4.

The main objective of this study is to assess the toxicity and the pharmacokinetic (PK) parameters of the Drug Product (DP). Subjects will be recruited to the study via study advertisement on social media and the subjects will be adequately compensated. The DP will be self-administered intranasally once daily for 1 day or seven days, depending on the study cohort. PK parameters will be evaluated for 4 subjects participating in the 7 daily DP doses study cohorts. Blood samples for this purpose will be collected at several time points (as described in SOA) during Day 1 and Day 7 of treatment. Toxicity will be evaluated during the entire study period.

Patients receiving a single dose will arrive for a follow-up visit 72 hours following DP administration (24 hours following hospital discharge), again 7 days (+-2 days) following DP administration, and again 14 days (+-2 days) following DP administration. Subjects receiving a daily dose for 7 days will be followed up 14 days (+-2 days) following initial DP administration (7 days (+-2 days) following final DP administration).

Safety review by the DSMB will occur following treatment of the last subject in each study arm.

Stage I Inclusion Criteria

1. Age ≥ 18 years in healthy condition
2. Able and willing to sign ICF

Stage I Exclusion Criteria

1. Known hypersensitivity to any of the DP ingredients.
2. Pregnant or lactating woman.
3. Participation in another clinical study within 4 weeks from screening
4. Patient has a positive test for HBV, HCV or HIV
5. Subjects diagnosed with allergic rhinitis and/or deviated septum and/or sinusitis.
6. Any medical condition that in the investigator's opinion will jeopardize the patient's ability to follow the protocol.

Stage II Inclusion Criteria

1. Age ≥ 18 years
2. Laboratory confirmed SARS-CoV2 Infection by nasopharyngeal RT-PCR.
3. COVID-19 symptoms within 3 days of symptoms onset
4. Patients diagnosed with COVID-19 that are not hospitalized (classified on the NIAID 8-point ordinal scale as 1 or 2).

Stage II Exclusion Criteria

1. Patients who may require hospitalization during the study
2. Immunocompromised COVID-19 patients.
3. Known hypersensitivity to any of the DP ingredients.
4. Patient has a positive test for HBV, HCV or HIV
5. Pregnant or lactating woman.
6. Participation in another clinical study within 4 weeks from screening
7. Subjects diagnosed with allergic rhinitis and/or deviated septum and/or sinusitis.
8. Any medical condition that in the investigator's opinion will jeopardize the patient's ability to follow the protocol.

The study will begin with recruitment for the single 25 mg dose arm /vehicle arm, and once all subjects have been treated and attended their first follow-up visit with no significant safety issues, recruitment of participants for the single 50 mg dose arm/vehicle arm and the multiple 25 mg dose arm/vehicle arm. Once subjects from the multi 25 mg dose Cohort have attended their follow-up visit with no significant safety issues, recruitment for the final multiple 50 mg dose arm/vehicle arm may commence.