Therapeutic Options in High-Risk Nonmuscle Invasive Bladder Cancer During the Shortage of Bacillus Calmette-Guérin

Abstract

Bladder cancer is the second most common malignant tumor of the urinary tract and is the seventh most common cancer among men worldwide and 17th among women. Seventy to eighty percent of bladder cancers are nonmuscle invasive bladder cancer (NMIBC) at the first diagnosis, and about 20%-25% of patients progress to invasive bladder cancer. According to the EORTC (European Organisation for Research and Treatment of Cancer) risk classification study, patients with high-risk NMIBC (T1, high grade/G3, carcinoma in situ) have a 5-year recur risk of up to 80% and a 50% chance of advance. Treatment options for high-risk NMIBC recommend Bacillus Calmette-Guérin (BCG) intrabladder infusion therapy after transurethral resection of bladder tumor, and intrathecal bladder chemotherapy such as mitomycin C or epirubicin, or early radical bladder resection may also be considered in recurrent high-risk patients. Among them, BCG intrathecal bladder infusion therapy has been demonstrated to reduce progression to mycoinvasive disease and has been used as a primary treatment for high risk NMIBC patients. BCG intrathecal infusion therapy reported that less than 10%-20% of patients in the responding group developed myoinvasive disease, while 66% of the patients in the poor response group developed myoinvasive disease. However, because BCG is made from Mycobacterium bovis, mass production is difficult due to a number of factors, such as the strength, quality, purity, and potency of BCG vaccines that pharmaceutical companies need to control. Most of all, BCG vaccines are prone to bacterial contamination due to long incubation periods and expensive specialized equipment. These factors eventually led to the closure of the Sanofi Institute for BCG vaccines in 2012, which continues the difficulties Merck has faced due to the lack of BCG supplies. Because BCG is a generic drug, the 2003 Medicare Modernization Act limited costs by up to 6% above the Medicare average selling price. Therefore, in 2016, Sanofi did not find any party to continue BCG's manufacturing technology and acquire the company, as a result, it announced that it will stop production in the United States, Canada, the United Kingdom, and France. In this article, we will discuss how to treat high-risk NMIBC patients under these BCG deficiencies, along with some of the treatment options that can be implemented in cases of drug shortage.