Some doctors feel that the time point for evaluation of BCG effectiveness should be at 3 months for papillary tumours and 6 months for CIS (except when disease progression was observed at 3 months); this implies 6 initial and 2 rounds of 3 x BCG maintenance for CIS. Other doctors may recommend alternate protocols or other intravescial agents or combination of agents. Wide variation of treatment plans have been described on this site.
Dr. Lamm's studies indicate that when BCG has failed to treat CIS, after the above, that restarting BCG may be effective in an additional 14% of CIS cases, assuming tumors remain non invasive. Other agents may also be effective following BCG Failure. There are a number of choices for doctor and patient to consider, based on the specifics of the case.
There is no "stronger" dose of BCG . It is possible to apply too much BCG. It is common to reduce the BCG dose on additional treatments if the side effects are too great. There are procedures that use heat or electric force in the bladder, in combination with medical agents, to increase the absorption of the agent.
Talk to your doctor, ask about both conservative and aggressive treatment plans he can recommend for YOUR situation. If you like, ask for a referral to a bladder cancer specialist to help you decide how you would like to proceed.
Best
Jack