Treatment of mild COVID-19 is basically performed at an outpatient clinic, then when the symptom and clinical findings exacerbate to a moderate level, patients are admitted. There is no standard treatment for mild cases. This study will investigate whether ivermectin administration suppresses the replication of SARS-CoV-2 in mild to moderate COVID-19 by investigating the negative rate of SARS-CoV-2 PCR by a randomized controlled trial. Subjects are assigned to two groups, the placebo group, and the ivermectin group. The target number of each treatment arm is 120, a total of 240 cases. A single oral administration of 200 ㎍/kg of ivermectin or an ivermectin-free placebo will be administered on an empty stomach. Time to negativization of SARS-CoV-2 PCR as the primary endpoint with additional efficacy and safety of the process will be investigated.

Inclusion Criteria:

1. A person who has been diagnosed with COVID-19 (including asymptomatic) by the COVID-19 PCR test (SARS-CoV-2 nucleic acid detection) within 3 days before the qualification test.
2. A person with oxygen saturation (SpO2) in the room air of 95% or more.
3. A person who are 20 years or older at the time of obtaining consent.
4. A person who weigh 40 kg or more at the time of qualification test.
5. A person who understands the content of this clinical trial and can obtain written consent to participate in the clinical trial.

Exclusion Criteria:

1. A woman who is in lactation period or who may be pregnant, or those who do not agree to prevent pregnancy by medically appropriate means for up to 7 days after study drug administration.

   Medically appropriate contraception means that using a combination of two or more of the following: not having sexual intercourse, taking surgical sterilization such as vasectomy or intrauterine device, taking oral contraceptive, using condom.

2. A person who has severe liver damage (AST or ALT at the time of qualification test is more than 3 times the upper limit of institutional standard and total bilirubin is more than twice the upper limit of institutional standard value), renal disorder (eGFR of eligibility test value 30 mL/min/1.73m2 or less).

3. A person with hypersensitivity to ivermectin.

4. A person with a history of severe drug allergies such as Stevens-Johnson syndrome, toxic epidermal necrolysis.

5. A person who has received the prohibited medication within the past month (within the past 6 months for biologics), or those who need to use the prohibited medication during the clinical trial period.

6. Those who are scheduled to receive SARS-CoV-2 vaccination from the date of consent to the end of the follow-up period.

7. A person who are currently participating in other clinical trials or who have participated in other clinical trials within 30 days before obtaining consent.

8. In addition, a person who is determined to be unsuitable as a subject of this clinical trial by the principal investigator."