The multivariate analysis showed that the independent variables associated with a satisfactory response in respect of improvement in lung function after 12 months of treatment with omalizumab were the absence of COPD (OR = 12.16; 95% CI = 2.45–79.49), the FCGR2B rs3219018-C allele (OR = 8.6; 95% CI = 1.12–117.15), the GATA2 rs4857855-T allele (OR = 15.98; 95% CI = 1.52–519.57), and the FCGR2A rs1801274-G allele for the genotypic model (OR = 13.75; 95% CI = 2.14–142.68; AG vs. AA, and OR = 7.46; 95% CI = 0.94–89.12; GG vs. AA, respectively) (Table 3). The gene discussed is FCGR2A; the disease is chronic obstructive pulmonary disease.