A 35-year-old male presented with gross haematuria with similar episodes occurring in the past 6 months. No H/O of fever, pain, or burning on urination weight loss or increased sense of urgency to void. There was no history of exposure to toxins either at work or during recreational activities. The patient underwent fibreoptic cystoscopy. A mass was noted in the fundus of the bladder, biopsy of which is shown in Figure. What is the drug of choice of the likely cause?