A multivariate analysis including skin rash as a variable confirmed that the administration of minocycline for 30 days or longer correlated with good PFS and overall survival (OS) with first-line EGFR-TKIs (HR 0.44 [95% CI 0.27–0.73], p = 0.0014 and HR 0.50 [95% CI 0.27–0.92], p = 0.027, respectively). The gene discussed is EGFR; the disease is exanthem.