Comparing Bacillus Calmette-Guérin (BCG) strains in convalescent COVID-19 patients.

We previously published results of the BATTLE trial, showing that patients recently infected with SARS-CoV-2 can benefit from receiving Bacillus Calmette-Guérin (BCG) with minimal adverse effects. The study incorporated two strains of this vaccine. In this study, patient outcomes were compared based on the strain of BCG because different strains have been shown to have different immunogenicity. BATTLE was a double-blind controlled trial of COVID-19 convalescent patients; symptom progression, injection-site lesion characteristics and adverse effects were compared between recipients of placebo, Russian BCG strain or Brazilian BCG strains. There was no statistically significant difference between the two BCG strains in terms of symptom progression, lesion-size or type. The two strains have similar clinical outcomes in COVID-19 convalescent patients.