KEY TAKEAWAYS
- The PURE-01 study (NCT02736266) was a Phase 2 clinical trial that evaluated the efficacy of neoadjuvant pembrolizumab before radical cystectomy in muscle-invasive urothelial bladder carcinoma patients.
- The intention-to-treat population showed 74.4% event-free survival with a median follow-up of three years and 83.8% overall survival.
- PD-L1 expression was the strongest predictor of response post-RC, with significantly better EFS observed in the high tertile.
- The claudin-low and basal/squamous subtypes exhibited the lowest event rates.
- The results of the PURE-01 trial further corroborate the sustained efficacy of preoperative pembrolizumab treatment.
Neoadjuvant immune-checkpoint inhibitor (ICI) therapy before radical cystectomy (RC) in patients with muscle-invasive urothelial bladder cancer was first implemented in the PURE-01 study (NCT02736266) (MIBC). Researchers report the survival rates after a median of three years of follow-up.
A total of 155 patients have been included in the “intention to treat” (ITT) population analysis. Time to radiographic progression precluding RC, the commencement of neoadjuvant chemotherapy, recurrence after RC, or death was considered event-free survival (EFS) once treatment with pembrolizumab was begun. Recurrence-free survival (RFS) after RC and overall survival (OS) were additional measures of success. EFS was analyzed using multivariate Cox regression. Kaplan-Meier analysis evaluated EFS outcomes based on baseline PD-L1 combined positive score (CPS) and molecular subtypes.
A 36-month event-free survival (EFS) was 74.4% [95% CI, 67.8-81.7], and OS was 83.8% [95% CI, 77.8-90.2) in the ITT population after a median (interquartile range, IQR) follow-up of 39 (30-47) months. A total of 143 (92.3%) patients were treated with RC. Patients who had ypT0N0, ypT1/a/isN0, ypT2-4N0, and ypTanyN1-3 responses had a 36-month RFS of 96.3% (95% CI, 91.6-100), 74.9% (95% CI, 60.2-93), and 58.3% (95% CI, 36.2-94.1), respectively, among the group of patients who did not receive further treatment (N = 125). Lower tertile PD-L1 EFS was 59.7%, middle tertile PD-L1 EFS was 76.7%, and high tertile PD-L1 EFS was 89.8% (P = 0.0013). The basal/squamous and claudin-low subtypes showed the fewest occurrences overall.
PURE-01 results, with a median follow-up of 3 years, further show the long-term effectiveness of neoadjuvant pembrolizumab before RC. The expression of PD-L1 was found to be the most significant indicator of long-term survival after RC.
Clinical Trial: https://clinicaltrials.gov/ct2/show/NCT02736266
Basile G, Bandini M, Gibb EA, Ross J, Raggi D, Marandino L, Padua T, Crupi E, Colombo R, Colecchia M, Lucianò R, Nocera L, Moschini M, Briganti A, Montorsi F, Necchi A. Neoadjuvant Pembrolizumab and Radical Cystectomy in Patients with Muscle-Invasive Urothelial Bladder Cancer: 3-Year Median Follow-Up Update of PURE-01 Trial. Clin Cancer Res. 2022 Dec 1;28(23):5107-5114. doi: 10.1158/1078-0432.CCR-22-2158. PMID: 36190522.
