San Francisco, California (UroToday.com) For patients with high risk or recurrent non-muscle invasive bladder cancer, BCG is the most commonly used intravesical agent. Many other therapies exist but BCG is considered the preferred agent by many due to a lack of studies showing a consistently superior agent. Unfortunately, there has been a national BCG shortage over the past year (and has occurred in years past such as 2014-2016) and BCG is not consistently available at many institutions.
The AUA and SUO have made a series of specific recommendations regarding the optimal use of BCG (do not use in low risk disease, consider intravesical chemotherapy for first line intermediate risk disease, etc), but the BCG shortage demonstrates an unmet need for patients with high risk or recurrent non-muscle invasive bladder cancer.
One strategy to conserve BCG given the shortage and reduce toxicity would be to reduce the frequency of BCG instillations in NMIBC. NIMBUS was a multicenter prospective randomized trial to compare the efficacy and safety of two adjuvant treatment schedules: 1) Induction cycle BCG-full dose; weeks 1 through 6 plus maintenance cycles at months 3, 6 and 12 (weeks 1,2,3); total 15 full doses. 2) Induction cycle BCG-full dose (reduced frequency); weeks 1,2,6 plus maintenance cycles at months 3,6 and 12 (wks. 1,3); total 9 full doses.
Summary
Data on 345 patients are presented today. The primary endpoint was time to first recurrence. Baseline characteristics are shown below.
46% of patients were Ta and 54% were T1. The majority of patients no had concomitant CIS (73%).
There was a recruitment delay due to the BCG shortage and this led to a redefinition of the statistical assumptions.
The consort diagram is shown below.
In terms of outcomes, recurrence was detected in 27% of patients with reduced frequency BCG compared with 12% in the standard frequency schedule. 0.6% of patients in the reduced frequency schedule had progression to T2 or greater compared with 3.4% in the reduced frequency. As expected, the percentage of AEs was lower in reduced frequency compared with standard frequency.
This trial was stopped early due to safety analysis showing that the reduced frequency of BCG was inferior to the standard frequency, with a clear difference in time to recurrence and number of recurrences.
Conclusions
Reduced frequency of BCG is inferior to standard BCG installation schedule and leads to decreased time to recurrence and an increased number of recurrences. In an era where BCG shortage is common, we must continue to innovate and develop novel therapies to add to the armamentarium of treatment for NMIBC.
Presented by: Marc-Oliver Grimm, MD, Professor and Chairman, Department of Urology, Jena University Hospital, Jena, Germany
Written by: Jason Zhu, MD. Medical Oncologist, Division of Genitourinary Cancers, Levine Cancer Institute Twitter: @TheRealJasonZhu at the 2020 Genitourinary Cancers Symposium, ASCO GU #GU20, February 13-15, 2020, San Francisco, California