Neoadjuvant chemotherapy plus tislelizumab followed by radiotherapy demonstrated perfect efficacy and tolerable toxicities, according to results from a phase 2 study.

Feng Wen, West China Hospital at Sichuan University, Chengdu, China, presented the results on Friday, February 17, 2023, at the 2023 ASCO Genitourinary Cancers Symposium in San Francisco, CA.

This open-label study included 28 patients with muscle-invasive bladder cancer who received 3 to 4 cycles of neoadjuvant chemotherapy plus tislelizumab followed by radiotherapy for those patients without progressive disease. The primary end point of the study was complete response rate, with secondary end points including progression-free survival (PFS), bladder-intact disease-free survival (DFS), overall survival (OS), and toxicity.

At a median follow-up duration of 14.2 months, 23 received radiotherapy and 16 completed efficacy evaluation. The complete response rate was 100%, with 14 patients at T0 following radiotherapy and 2 patients at Tis. The 2 patients at Tis achieved T0 following Bacillus Calmette-Guérin therapy. There was 1 patient with distant metastasis and no deaths. The 1-year PFS rate, 1-year bladder-intact DFS, and 1-year OS were all 100%.

The incidence of grade 3 and 4 hematological system adverse events were 23.3% and 2.3%, respectively. There were 3 incidents of grade 1 immunotherapy-related abnormality of thyroidal function, 3 of grade 2 myositis, 3 of frequency with urgency, nocturnia, and dysuria, and 1 incidence of reduced bladder capacity.

Dr Wen and coauthors concluded that this treatment regimen “may be an optimal strategy for high-risk/locally advanced [muscle-invasive bladder cancer] patients with bladder-preserving willingness.”

Source:

Wen F, Lin T, Zhang P, Tan P, Zheng X, and Shen Y. A phase 2, open-label study of neoadjuvant chemotherapy plus tislelizumab followed by radiotherapy-based, bladder-preserving treatment for high risk/locally advanced muscle invasive urothelial bladder cancer (HOPE-02). Presented at 2023 ASCO Genitourinary Cancers Symposium; February 17-19; San Francisco, CA. Abstract 516