The comparison of efficacy between the connaught and tice strains of bacillus calmette-guérin in patients with non-muscle-invasive bladder cancer in Taiwan

Purpose: The purpose of the study is to compare the efficacy of Bacillus Calmette-Guérin (BCG) strains, Connaught (ImmuCyst®), and TICE (OncoTICE®) in patients with nonmuscle invasive bladder cancer (nMIBC). Materials and Methods: Patients with nMIBC who underwent transurethral resection between March 1997 and December 2017 were enrolled. TICE was used due to the Connaught strain shortage since 2012; hence, direct comparison of the two strains could not be performed. An intravesical instillation (IVI) regimen of mitomycin-C, doxorubicin, and cisplatin (MDP) was used as the reference for comparison. The MDP group was separated into two cohorts (MDP-1 and MDP-2) that matched the same time period of Connaught and TICE treatment. Patients who did not complete the IVI course before disease recurrence or progression or were not followed up for at least 24 months were excluded. Results: A total of 730 patients were included in the analysis. There were 67 (9.2%), 38 (5.2%), and 625 (85.6%) patients who received the Connaught, TICE, and MDP treatment, respectively. During a median follow-up duration of 59 months, the recurrence rates of the Connaught, MDP-1, TICE, and MDP-2 groups were 10.5%, 22.8%, 28.9%, and 23.0%, respectively. Both BCG groups had higher tumor grades and more instances of carcinoma in situ than their corresponding MDP cohorts. The Connaught and TICE strains had similar effects in preventing tumor recurrence (Connaught vs. MDP, P = 0.876; TICE vs. MDP, P = 0.556). In the multivariable Cox proportional hazard model that included all patients, the Connaught and TICE groups had a similar risk (hazard ratio = 0.784 and 0.850) of recurrence compared to the MDP protocol. Although progression events were more frequently noticed in the Connaught group, the small number of events limited the analysis. Conclusion: The BCG strains, Connaught and TICE, had similar efficacy in reducing bladder tumor recurrence in nMIBC patients. Both strains resulted in similar bladder recurrence-free survival rates to chemotherapeutic agents.