Inclusion Criteria:  RT-PCR or antigen test confirmed COVID-19 cases Aged 50 years and above,with at least one co-morbidities* Within the first 7 days of illness (from symptom onset) Mild to moderate clinical severity  Exclusion Criteria:  Asymptomatic stage 1 patients Patients with SpO2 less than 95% at rest. (unless it is an expected baseline SpO2 due to preexisting disease, eg. COAD or pulmonary fibrosis) Patients who need oxygen supplements Patients with concomitant bacterial, fungal, parasitic or other viral infections prior to enrollment. Patients with severe hepatic impairment (>Grade 3: ALT >10 times of upper normal limit) Malabsorptionsyndromeorotherclinicallysignificantgastrointestinaldisease that may affect absorption of the study drug (non-correctable vomiting, diarrhea, ulcerative colitis, and others). Pregnant or nursing women. Female patients of reproductive age who cannot consent to contraceptive use of oral contraceptives, mechanical contraceptives such as intrauterine devices or barrier devices (pessaries, condoms), or a combination of these devices from the start of ivermectin administration to 7 days after the end of ivermectin administration. Male patient who has female partner of reproductive age and he cannot agree to use contraception from the start of ivermectin treatment till 7 days after treatment. Patients receiving chemotherapy Patients who received interferon or drugs with reported antiviral activity against COVID-19 (favipiravir, hydroxychloroquine sulfate, chloroquine phosphate, lopinavir-ritonavir combination, remdesivir) in the past 7 days before enrollment. Patients in whom this episode of infection is a recurrence or reinfection of COVID- 19. Patients who have previously received ivermectin. Patient receiving warfarin or any medications known to interact with ivermectin. Acute medical or surgical emergency (eg. DKA/MI/stroke). Other patients judged ineligible by the principal investigator or sub-investigator.