Bacillus Calmette-Guérin Retains Clinically Relevant Viability for up to 72 Hours After Reconstitution: Potential Implications for Clinical Practice in Times of Shortage.

There have been repeated supply shortages of bacillus Calmette-Guérin (BCG), the gold-standard immunotherapy for patients with high-grade non-muscle-invasive bladder cancer (NMIBC). Organizations have issued guidance on coping with this shortage, including administering split-dose BCG such that one vial may treat up to three patients. However, logistical implementation of this strategy in a real-world setting is hampered by the recommendation to use BCG within 2 h of reconstitution. We assessed BCG viability in terms of colony-forming units (CFUs) and demonstrated that viability remained constant for at least 8 h after reconstitution (decline at 8 h of 9.1% for lot 1 [p =  0.3] and 4.8% for lot 2 [p =  0.2]). While the viability at 24 h was lower, it did not drop to a level below that of reducing the BCG dose to one-third (67% for lot 1 and 60% for lot 2) and remained close to 50% for at least 72 h. An in vitro model using co-culture of BCG and leukocytes with a BCG-sensitive cell line (RT4-V6) demonstrated no decrease in the cytotoxic potential of BCG at 72 h. In times of shortage, BCG vials may be split and administered for up to at least 8 h (or even 72 h) after reconstitution, allowing more patients to benefit from BCG while placing less strain on the logistics of clinical practice. PATIENT SUMMARY: The current supply of and increased demand for bacillus Calmette-Guérin (BCG), used in the treatment of bladder cancer, have led to repeated BCG shortages. One way to address this is to provide a reduced BCG dose to allow more patients to be treated. In this study we found that BCG viability remains clinically relevant up to 72 h after reconstitution, thus allowing for more patients to be treated from a single vial.

European urology oncology. 2020 May 28 [Epub ahead of print]

Nathan Brooks, Supriya Nagaraju, Justin Matulay, Xiang-Yang Han, Ashish M Kamat

Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA., Department of pathology and laboratory medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.