Neoadjuvant gemcitabine-cisplatin plus tislelizumab in persons with resectable muscle-invasive bladder cancer: a multicenter, single-arm, phase 2 trial

Abstract

Programmed death 1 blockade (tislelizumab) has been approved for metastatic urothelial carcinoma but not as part of neoadjuvant therapy for muscle-invasive bladder cancer (MIBC). In this multicenter single-arm trial (ChiCTR2000037670), 65 participants with cT2-4aN0M0 MIBC received neoadjuvant gemcitabine-cisplatin plus tislelizumab; 57 of them underwent radical cystectomy (RC). The primary endpoint of pathologic complete response (pCR) rate was 50.9% (29/57, 95% confidence interval (CI) 37.3-64.4%) and the pathologic downstaging (secondary endpoint) rate was 75.4% (43/57, 95% CI 62.2-85.9%) in participants undergoing RC. Genomic and transcriptomic analyses revealed three MIBC molecular subtypes (S): S1 (immune-desert) with activated cell-cycle pathway, S2 (immune-excluded) with activated transforming growth factor-β pathway and S3 (immune-inflamed) with upregulated interferon-α and interferon-γ response. Post hoc analysis showed pCR rates of 16% (3/19, S1), 77% (10/13, S2) and 80% (12/15, S3) (P = 0.006). In conclusion, neoadjuvant gemcitabine-cisplatin plus tislelizumab for MIBC was compatible with an enhanced pCR rate.