We thank Dr. Herr for his thoughtful comments and for highlighting the historical and clinical relevance of immune priming to enhance intravesical BCG efficacy in non–muscle-invasive bladder cancer (NMIBC). We fully agree that early observations linking purified protein derivative (PPD) reactivity and better outcomes after bacillus Calmette-Guérin (BCG) therapy provided the first clinical evidence that pre-existing mycobacterial immunity can modulate therapeutic responses [1–6].
We thank Dr. Herr for his thoughtful comments and for highlighting the historical and clinical relevance of immune priming to enhance intravesical BCG efficacy in non–muscle-invasive bladder cancer (NMIBC). We fully agree that early observations linking purified protein derivative (PPD) reactivity and better outcomes after bacillus Calmette-Guérin (BCG) therapy provided the first clinical evidence that pre-existing mycobacterial immunity can modulate therapeutic responses [1–6].