Enhanced power bacillus Calmette-Guérin—possibly too much of a good thing

Intravesical bacillus Calmette-Guérin (BCG) immunotherapy is the standard adjuvant treatment in patients with intermediate- and high-risk non-muscle invasive bladder cancer (NMIBC) after transurethral resection of the bladder tumour (TURB). It was widely proven, that this therapy reduces the risk of tumour recurrence and, what is more important, the risk of cancer progression. However, despite decades of BCG usage, precise mechanism, optimal schedule, dosage and various other details remain unknown. Furthermore, some patients do not respond well to the therapy, while others develop side effects. Finally, we have to face the BCG shortage because of production and logistics issues (1). All these factors motivate and promote the search for BCG alternatives or classic BCG ameliorations.