Under the influence of complex antiviral treatment, a significant decrease in TMPRSS2 and IL-6 was found in patients with moderate COVID-19, with decreases of 16.38% (p = 0.014) and 40.62% (p < 0.001); in patients with severe COVID-19, the decreases were 11.30% (p = 0.049) and 48.24% (p < 0.001), respectively. Here, TMPRSS2 is linked to COVID-19.