Stability of reconstituted freeze-dried Bacille Calmette-Guérin used for intravesical immunotherapy for bladder cancer.

The product monographs for the commercially available products of Bacille Calmette-Guerin (BCG) state they must be used immediately following reconstitution. We hypothesized that the viability of the reconstituted preparations of BCG would not be altered for a period of up to 4 hours thus allowing a longer time interval between full preparation and its intravesical administration. Vials of freeze-dried ImmuCysttrade mark (Connaught Laboratories) and TICEtrade mark BCG (Organon-Teknika) were fully reconstituted in approximately 50 ml of saline and aliquots of the fully reconstituted product were serially diluted and inoculated onto freshly prepared Lowenstein-Jensen slants and colony counts were conducted at 0, 2, and 4 hours. The colony counts of the freeze-dried preparations of BCG varied between 0.1 and 0.3 x 108 and between 0.6 and 1.1 x 108 per reconstituted volume at 4 hours for the Connaught and TICE strains, respectively. There was no decrease in the colony counts between 0 and 4 hours for either product. There were no significant differences in the viability of the fully reconstituted freeze-dried preparation of BCG for up to 4 hours after complete reconstitution. These findings would suggest some latitude may be provided for institutions where the product is fully reconstituted prior to its actual administration.