Split-dose cisplatin plus gemcitabine use and associated clinical outcomes in the first-line (1L) treatment of locally advanced or metastatic urothelial cancer (la/mUC): Results of a retrospective observational study in Germany (CONVINCE)

Platinum-based chemotherapy (PBC) followed by avelumab 1L maintenance in patients without progressive disease is standard 1L treatment for la/mUC. In patients ineligible for cisplatin at the standard dose schedule (C; 1 day per cycle), carboplatin (Cb) or a split-dose schedule of C (35 mg/m2 on days 1 + 8) are alternative options. The effectiveness of these regimens compared with standard-dose C has not been extensively examined, especially in a real-world (rw) setting. In this study, we compared clinical outcomes to PBC in patients with la/mUC who received 1L gemcitabine (G) with split-dose C (CG-S) vs standard-dose CG or CbG regimens. The CONVINCE study was initiated in Dec 2021 and enrolled 188 patients who received 1L PBC in 2019-2020 at 27 oncology or urology institutions (8 hospitals/19 office-based practices) across Germany. Objective response rates (ORRs) and rw progression-free survival (rwPFS) and overall survival (rwOS) were compared in the following subgroups: CG-S vs CG and CG-S vs CbG. Of 124 patients who received 1L PBC with G, 27 (21.8%) received CG-S, 75 (60.5%) CG, and 22 (17.7%) CbG. Median follow-up was 16.5 months. A Cox regression analysis including several characteristics (age, sex, Eastern Cooperative Oncology Group performance status [ECOG PS], comorbidities) showed no significant differences in rwPFS between CG-S vs CG and CG-S vs CbG subgroups. This rw study provides valuable insights into the use of 1L CG-S in routine clinical practice in Germany, where C administered in split-dose schedule showed comparable outcomes to standard-dose C or Cb. The analysis suggests that CG-S can be a viable alternative for administering 1L PBC in patients with la/mUC for whom standard-dose C may be unsuitable, without compromising treatment effectiveness.Table: 2388PParameterCG-S (n=27)CG (n=75)CbG (n=22)p value CG-S vs CGp value CG-S vs CbGMale, %70.473.377.2–Age, median (range), years66 (50-81)69 (52-81)73 (59-84)ECOG PS at diagnosis 0/1/2 (%)59/37/455/40/546/50/41L PBC cycles, median, n546rwPFS rates (Kaplan-Meier), %6 mo8577860.250.679 mo63575512 mo37393218 mo152314rwPFS, median, mo10.510.59.10.350.24rwOS rates (Kaplan-Meier), %6 mo1001001000.060.159 mo961009112 mo85858618 mo376945rwOS, median, mo14.418.816.70.060.14Best response (physician assessment)Evaluable, n (%)25 (92)69 (92)22 (100)–Complete response, %8.011.618.2Partial response, %56.037.740.9ORR, %64.049.359.10.840.65 Open table in a new tab