(UroToday.com) The 2022 American Urological Association (AUA) Annual Meeting included a session on non-invasive bladder cancer and a presentation by Dr. Michael O’Donnell discussing sequential endoluminal cabazitaxel and gemcitabine with pembrolizumab for docetaxel-unresponsive non-muscle invasive urothelial carcinoma of the upper and lower urinary tracts. Sequential intravesical gemcitabine and docetaxel have shown over 50% 2-year high-grade recurrence free survival in patients with BCG-unresponsive non-muscle invasive bladder cancer. Subsequent recurrences may be due to overexpression of p-glycoprotein drug efflux pumps induced by prolonged docetaxel exposure. Cabazitaxel has reduced efflux pump affinity and retains efficacy following docetaxel resistance in prostate cancer. Dr. O’Donnell and colleagues reported outcomes of patients treated with sequential endoluminal gemcitabine/cabazitaxel and intravenous pembrolizumab for patients with high-risk docetaxel-unresponsive NMIBC who refused or were poor candidates for cystectomy.
This is a retrospective analysis of 13 patients (18 treated units; 14 lower tracts, 4 upper tracts) who were treated with endoluminal gemcitabine/cabazitaxel and intravenous pembrolizumab from September 2020 to July 2021 with at least 3-month evaluation. Patients received 6 weekly endoluminal 50 cc instillations of sequential 1g gemcitabine (90 minutes) and 5mg docetaxel (90 minutes) with concomitant intravenous pembrolizumab (200/400mg q3/6weeks respectively). Maintenance treatment was administered every 2-4 weeks until disease progression or unacceptable toxicities. The primary outcome was complete response at 3 month evaluation, defined as no disease on cystoscopy, bladder/upper tract wash cytology, or for-cause biopsies.
The median follow-up for this analysis was 15 months. Prior treatments included BCG in 92%, gemcitabine + docetaxel in 100%, and additional docetaxel containing regimens in 79% of patients. Considering treated units, 83% presented with positive cytology or biopsy proven CIS, 6% with high grade Ta and 11% with high grade T1 disease. At first evaluation, 86% patients and 89% treated units had complete response. In those with at least 6 months of post-treatment evaluation, 7/10 (70%) patients and 9/12 (75%) treated units remained disease-free. The median RFS among responders was 15 months, and the cystectomy free survival rate was 62%. Overall there was a 92% CSS and OS rate (one patient was lost to follow-up) and 5 patients underwent, or will undergo radical cystectomy (pT0, pTisN0, pT2N1, pTisN2, cystectomy after neoadjuvant chemotherapy pending). With regards to dose modifications, one patient did not start pembrolizumab secondary to fatigue, five required dose modification/holiday of gemcitabine/cabazitaxel due to cystitis, and 2 patients stopped pembrolizumab due to hepatitis/arthralgias.
Dr. O’Donnell concluded his presentation discussing sequential endoluminal cabazitaxel and gemcitabine with pembrolizumab for docetaxel-unresponsive non-muscle invasive urothelial carcinoma of the upper and lower urinary tracts with the following take-home points:
- This regimen showed promising early efficacy in heavily pretreated patients with high-risk NMIBC
- The ∼54% of patients requiring dosing adjustments may reflect determination of optimal dosing
- Prospective evaluation of this regimen is underway
Presented by: Michael A. O'Donnell, MD, University of Iowa, Iowa City, IA
Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, @zklaassen_md on Twitter during the 2022 American Urological Association (AUA) Annual Meeting, New Orleans, LA, Fri, May 13 – Mon, May 16, 2022.