The usual recommended BCG regimen is the 6 week induction period and then three once-a-week doses about every three months for what seemed to me to be forever!!
(I think, in my case, it was two years.)
Dr. Lamm, in Phoenix, AZ, is the expert on this and this is his summery of the protocol
www.bcgoncology.com/treatment/bcgInst.html
Research has shown that the maintenance treatments improve the effectiveness of the BCG significantly.
Sara Anne