The shortage of bacillus Calmette-Guerin (BCG) reduced the likelihood that patients with non-muscle invasive bladder cancer would receive a full course of induction therapy, according to research published in Urology.
Researchers found that the use of mitomycin C and other agents increased in response to the BCG shortage in the United States. However, patients with bladder cancer were still less likely to complete a full course of induction after the shortage began.
For this study, researchers analyzed 7971 Medicare beneficiaries who were diagnosed with non-muscle invasive bladder cancer during 2010-2017. All patients were at least 66 years of age, had been on Medicare for at least 12 months, and had received intravesical therapy within 1 year of their diagnosis.
A total of 2648 patients were treated before the BCG shortage began in July 2012, and 5323 patients were treated during the BCG shortage, which continued through the end of the study period (December 2018) and is still ongoing.
The proportion of patients receiving BCG induction decreased from 38.9% before the shortage began to 33.0% after — a 5.9% decrease (P <.001). The proportion of patients receiving BCG induction peaked in 2010 at 41.2% and hit its lowest point in 2015 at 30.5%.
There was state-level variation in the use of BCG. The greatest reductions in BCG use during the shortage period were seen in Virginia (29.3%), North Carolina (29.4%), and Washington (35.5%). The greatest increases in BCG use were seen in Georgia (14.3%) and Wisconsin (25.1%).
The proportion of patients who completed a full induction course of BCG decreased from 31.0% before the shortage began to 27.6% after (P =.002). The proportion of patients who received a full induction course with any intravesical agent decreased from 41.2% to 37.9% (P =.005).
The use of mitomycin C increased 3.0% during the shortage period (P =.005), and the use of other intravesical agents increased 2.5% (P =.018). There was no significant difference in gemcitabine use before and after the shortage began (P =.547).
The researchers noted that the BCG shortage has had downstream effects on the cost of treating bladder cancer in the US. When the BCG shortage was most severe, in 2014 and 2015, there was an increase in demand for mitomycin C, thiotepa, and valrubicin, which caused the average wholesale prices for these drugs to increase by 99% to 146%.
The researchers also pointed out that some of these agents have been associated with higher rates of tumor recurrence and disease progression compared with BCG. However, the combination of intravesical gemcitabine and docetaxel “is gaining favor” as a treatment option due to retrospective study results. Researchers are currently comparing the combination to BCG in the phase 3 BRIDGE trial (ClinicalTrials.gov Identifier: NCT05538663).
Chun B, He M, Jones C, et al. Variation in statewide intravesical treatment rates for non-muscle invasive bladder cancer during the BCG drug shortage. Urology. Published online March 25, 2023. doi:10.1016/j.urology.2023.02.044