Study aim: Main objective: to determine and comparison effect of Spirulina (Arthrospira Platensis) supplement on COVID-19 disease's outcomes (consisted of laboratory measures ; ventilator free days;) LOS ICU (length of stay in ICU); LOS Hospital (length of hospital stay) and mortality rate; clinical manifestations; severity and nutritional status) in patients admitted to intensive care units of hospitals during 4 weeks between intervention and control groups. Design: Randomized control trial, with control group, randomization using Random Number Table, phase 2 on patients with COVID-19 Settings and conduct: The study will be carried out among COVID-19 patients admitted in ICU hospitals. Spirulina supplement will be taken to patients during 28 days and the outcomes will be followed. Participants/Inclusion and exclusion criteria: Patients with positive PCR admitted in ICU will be included. Patients under 18 years of age; pregnant and lactating women and consumers of vitamins C and E, omega-3 and antioxidant supplements in the last 3 months; patients with severe renal failure; liver failure of the last stage (cirrhosis); uncontrolled hypertension; patients who do not have a functioning gastrointestinal tract and have not been prescribed oral or intravenous nutrition and also with drug / food allergies will be excluded in this study. Intervention groups: Intervention group are COVID-19 patients with routine drugs and 5gr/day Spirulina powder. Control group without placebo and take normal therapeutic drugs. Main outcome variables: IL6; ESR; CRP; O2SAT