The implementation of sacituzumab govitecan monotherapy heightened response rate among platinum-ineligible patients with metastatic urothelial cancer (mUC) that progressed post-prior checkpoint inhibitor therapy, according to results from a cohort of a phase 2 study. 

Daniel P. Petrylak, Yale School of Medicine, New Haven, CT, presented results on Friday, February 17, 2023, at the 2023 ASCO Genitourinary Cancers Symposium in San Francisco, CA. 

“[Sacituzumab govitecan] received accelerated FDA approval in April 2021 for [patients] with [metastatic urothelial carcinoma] who progression after [platinum] and [checkpoint inhibitor] therapies based on the positive results of the pivotal TROPHY-U-01 Cohort 1 study,” Dr. Petrylak and co-authors wrote. The current report shares the primary analysis of TROPHY-U-01 Cohort 2.

There were 38 platinum-ineligible patients with metastatic urothelial carcinoma enrolled in cohort 2 of this study. Patients had a median of 2 prior therapies, with 50% having received prior neo/adjuvant platinum chemotherapy, 18% prior enfortumab vedotin, and 3% prior erdafitinib.  

Patients were administered 10 mg/kg sacituzumab govitecan on days 1 and 8 of continuous 21- day cycles. The primary end point was objective response rate (ORR), with secondary end points including duration of response (DOR), progression-free survival (PFS), and overall survival (OS). 

At the data cutoff date of July 26, 2022, the median follow-up was 9.3 months (ranging from 0.5 months to 30.6 months). The ORR was 32% (32% partial response); median DOR was 5.6 months (n = 12); and median PFS was 5.6 months. The median OS was 13.5 months. 

Grade ≥3 treatment-related adverse events were observed in 68% of patients, the most prevalent being neutropenia (34%), anemia (21%), leukopenia (18%), fatigue (18%), and diarrhea (16%). The incidence of discontinuation due to treatment-related adverse events was 18%.

Results of this study show sacituzumab govitecan monotherapy demonstrated a high response rate and an appropriate safety profile within this patient population. As end points were met, Dr. Petrylak et al concluded, “These data support further evaluation of [sacituzumab govitecanin] patients with [metastatic urothelial carcinoma] post [checkpoint inhibitor] therapy.”

Source: 

Petrylak D, Tagawa S, Jain R, et al. Primary analysis of TROPHY-U-01 cohort 2, a phase 2 study of sacituzumab govitecan (SG) in platinum (PT)-ineligible patients (pts) with metastatic urothelial cancer (mUC) that progressed after prior checkpoint inhibitor (CPI) therapy. Presented at 2023 ASCO Genitourinary Cancers Symposium; February 17-19; San Francisco, CA. Abstract 520.