If it appears that efficacy of LPV/RTV were significantly associated with this SNP of ABCB1 in COVID-19 patients, then this genetic approach may be applied to other SNPs of ABCB1 as well as genetic polymorphisms of CYP450 gene of CYP3A4/5 affecting safety or efficacy of LPV/RTV in patients with COVID-19. The gene discussed is CYP3A4; the disease is COVID-19.