Which of the following is the most effective intravesical therapy for superficial bladder cancer

Bacillus Calmette-Guerin (BCG) is the main intravesical immunotherapy for treating superficial bladder cancer.BCG is put directly into the bladder through a catheter. The body's immune system cells are attracted to the bladder and activated by BCG, which in turn affects the bladder cancer cells. Treatment is usually staed a few weeks after a TURBT(trans urethral resection of bladder tumour) and is given once a week for 6 weeks at a dose of 120mg in 150ml of normal saline .Reference : page 1036 SRB's manual of surgery 5th edition