Chloroquine phosphate (Aralen phosphate) is an antimalarial and anti-inflammatory agent widely used for malaria and rheumatoid arthritis. Chloroquine phosphate acts as an inhibitor of autophagy and toll-like receptors, effectively suppressing SARS-CoV-2 (COVID-19) infection (EC50 = 1.13 µM). Chloroquine phosphate can be utilized in research on autophagy, lysosomal function, and tumor diseases.