In a particular correspondence, a metadata analysis of the efficacy of CP treatment based on 9 clinical studies (mostly case series) suggested that CP reduced viral loads (risk ratio 0.13, 95% CI 0.09-0.18; P<.001; n=75) and C-reactive protein levels (ratio of mean [ROM] 0.11, 95% CI 0.01-0.86; P<.05; n=42), and improved the clinical status of patients with COVID-19 (ROM 0.53, 95% CI 0.36-0.79; P<.01; n=149) when compared to baseline (date of CP transfusion) [147]. The gene discussed is CP; the disease is COVID-19.