Study aim: The effect of supplementation with vitamins A, D, E, C, B on disease severity and mortality in patients with COVID-19 Design: A randomized, double-blind, placebo-controlled clinical trial Settings and conduct: Only patients are unaware of the placement in the intervention or control group. Location: The intensive care unit is located at Imam Khomeini Hospital. Participants/Inclusion and exclusion criteria: Inclusion criteria : 1- Between 20 and 60 years old 2. Both men and women 3. The definitive or clinical diagnosis of COVID-19 4. Satisfaction with the study collaboration 5.BMI: 18.5-30 6. COVID-19 treatment protocol is almost identical in both groups 7- Patients not participating in other trials 8- No liver and kidney disorders Non-Entry Criteria: - Patients with rare and specific viral diseases such as HIV - Patients undergoing chemotherapy over the past month - Any other condition that the specialist diagnoses is very specific. Intervention groups: Patients were divided into intervention and control groups. Intervention group supplemented with vitamin D at 25,000 international units of vitamin A daily, 600,000 international units of vitamin D once daily, 300 units of vitamin E twice daily, 500 mg Vitamin C is taken 4 times a day and finally B vitamins are taken as a daily solute ampoule. The control group received no supplement or placebo. Main outcome variables: Variables: 1- Weight, height and BMI of patients 2. Severity of pulmonary involvement according to CT scan 3. Respiratory support (Insive or Non-Invasive) 4% oxygen saturation 5- Serum levels of WBC, CRP, IL6, TNF-α, IFN-G, ESR 6. The patient's body temperature 7. The presence or absence of involvement of other organs 8- Duration of hospitalization 9. Mortality