Purpose: We determined whether prophylaxis with ofloxacin could decrease the toxicity of bacillus Calmette-Guerin for transitional cell carcinoma of the bladder. We also investigated the impact of ofloxacin on bacillus Calmette-Guerin antitumor efficacy.
Materials and methods: In this randomized, double-blind, multicenter study 115 patients with primary or recurrent superficial bladder cancer (Ta/T1, CIS, G1-G3) and no prior bacillus Calmette-Guerin treatment were randomized to induction treatment with intravesical bacillus Calmette-Guerin (6 plus 3 instillations) plus 200 mg ofloxacin in group 1 or plus placebo in group 2. Adverse events were assessed using a detailed grid of classification for bacillus Calmette-Guerin related adverse events. Mean patient age +/- SD was 65.6 +/- 10.4 years in the 57 group 1 patients and 65.7 +/- 8.7 years in the 58 in group 2. Median followup was 369 and 374 days in groups 1 and 2, respectively.
Results: Ofloxacin significantly decreased by 18.5% the incidence of class II or higher moderate and severe adverse events between instillations 4 and 6. The percent of class III adverse events was significantly decreased by ofloxacin between instillations 1 and 9. Although ofloxacin decreased adverse events involving the lower urinary tract, it did not prevent class I adverse events. Compliance with full bacillus Calmette-Guerin treatment was also improved. Of patients in group 1, 80.7% received 9 instillations compared with 65.5% in group 2 (p = 0.092). At 12 months recurrence and progression rates in group 1 and 2 were 12.7% and 17.2%, and 5.5% and 1.7%, respectively.
Conclusions: Prophylactic ofloxacin decreased the incidence of moderate to severe adverse events associated with bacillus Calmette-Guerin intravesical therapy, particularly class III events, which are primarily associated with patient dropout. Compliance with induction and maintenance therapy may be improved by adjuvant ofloxacin therapy. However, long-term comparative studies with other preventive strategies must be done to confirm these initial findings with compliance and recurrence-free survival as the primary end points.