It has been noted in two extensive observational studies from Italy and France that biologic therapy may prove effective in protecting against severe COVID 19. It is reported that the biologics have a protective action against severe, poor-outcome COVID-19; however, they do not prevent the infection. In a case-control study including 1, 193 adult psoriasis patients on biologics or apremilast, for a duration of February 21 to April 9, 2020, it was seen that 22 of the 1,193 participants experience confirmed COVID-19 during the study period. Out of these, 17 were quarantined at home owing to their mild symptoms, five were hospitalized, but none of the patients was placed in intensive care or died.

It is suggested that the biologics enhance the risk of infection with the SARS-CoV-2 virus in psoriasis patients while protecting them against ICU admission and mortality. However, the mechanism of action of biologics in COVID 19 is not yet known.