Phase 2 trial of intravesical cabazitaxel, gemcitabine, and cisplatin (CGC) for the treatment of non-muscle invasive BCG unresponsive urothelial carcinoma of the bladder.

TPS4616 Background: For patients with non-muscle invasive bladder cancer (NMIBC) unresponsive to Bacille Calmette-Guerin (BCG), multi-agent intravesical trials have been limited. The goal of this Phase 2 study is to investigate the efficacy of intravesical chemotherapy consisting of sequential cabazitaxel, gemcitabine, and cisplatin (CGC) in the salvage setting. Phase 1 results reporting on 18 subjects demonstrated adverse events limited to local Grade 1 and 2 toxicities. Partial funding support for the trial was provided by a pharmaceutical company. Methods: This is a Phase 2 trial (NCT02202772) presently enrolling patients with BCG unresponsive NMIBC as defined by the FDA who refuse or are ineligible for radical cystectomy. All patients undergo pre-treatment transurethral resection of bladder tumor (TURBT) and a 6-week regimen of intravesical cisplatin (100mg), gemcitabine (2gm), and cabazitaxel (5mg). Each drug is instilled weekly except for cisplatin, which is given every other week. Complete response is defined as having no evidence of cancer on post-induction biopsy and negative urine cytology at 3 months. Complete responders proceed with monthly and bimonthly maintenance therapy without cisplatin in the first and second years, respectively, for a total of 24 months. Results: To date thirty-one patients have been enrolled (with target accrual of 33), of whom seven are female. One patient withdrew consent before first evaluation cystoscopy. Mean age thus far is 72 years. All patients have previously received at least two prior induction cycles of BCG, and meet FDA criteria for BCG unresponsive disease. All patients have biopsy proven high grade disease at enrollment; 8 (27%) have high grade T1 disease; and 20 (67%) patients have CIS. Conclusions: Salvage options for BCG unresponsive NMIBC are limited. The CGC protocol has been demonstrated to be safe in a previous Phase 1 study, and accrual for this Phase 2 is near completion. Clinical trial information: NCT02202772 .