Thomas Powles

IMPORTANCE: The data reported herein were accepted for assessment by the US Food and Drug Administration for Biologics License Application under priority review to establish the clinical benefit of durvalumab as second-line therapy for locally advanced or metastatic urothelial carcinoma (UC), resulting in its recent US approval. OBJECTIVE: To report a planned update of the safety and efficacy of durvalumab in patients with locally advanced/metastatic UC. DESIGN, SETTING, AND PARTICIPANTS: This is an ongoing phase 1/2 open-label study of 191 adult patients with histologically or cytologically confirmed locally advanced/metastatic UC whose disease had progressed on, were ineligible for, or refused prior chemotherapy from 60 sites in 9 countries as reported herein. INTERVENTION: Patients were administered durvalumab intravenous infusion, 10 mg/kg every 2 weeks, for up to 12 months or until progression, starting another anticancer therapy, or unacceptable toxic effects. MAIN OUTCOMES AND MEASURES: Primary end points were safety and confirmed objective response rate (ORR) per blinded independent central review (Response Evaluation Criteria In Solid Tumors [RECIST], version 1.1). RESULTS: A total of 191 patients with UC had received treatment. As of October 24, 2016 (90-day update), the median follow-up was 5.78 months (range, 0.4-25.9 months). The median age of patients was 67.0 years and most were male (136 [71.2%]) and white (123 [71.1%]). All patients had stage 4 disease, and 190 (99.5%) had prior anticancer therapy (182 [95.3%] postplatinum). The ORR was 17.8% (34 of 191; 95% CI, 12.7%-24.0%), including 7 complete responses. Responses were early (median time to response, 1.41 months), durable (median duration of response not reached), and observed regardless of programmed cell death ligand-1 (PD-L1) expression (ORR, 27.6% [n = 27; 95% CI, 19.0%-37.5%] and 5.1% [n = 4; 95% CI, 1.4%-12.5%] in patients with high and low or negative expression of PD-L1, respectively). Median progression-free survival and overall survival were 1.5 months (95% CI, 1.4-1.9 months) and 18.2 months (95% CI, 8.1 months to not estimable), respectively; the 1-year overall survival rate was 55% (95% CI, 44%-65%), as estimated by Kaplan-Meier method. Grade 3/4 treatment-related adverse events (AEs) occurred in 13 patients (6.8%); grade 3/4 immune-mediated AEs occurred in 4 patients (2.1%); and treatment-related AEs led to discontinuation of 3 patients (1.6%), 2 of whom had immune-mediated AEs that led to death (autoimmune hepatitis and pneumonitis). CONCLUSIONS AND RELEVANCE: Durvalumab, 10 mg/kg every 2 weeks, demonstrates favorable clinical activity and an encouraging and manageable safety profile in patients with locally advanced/metastatic UC. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01693562.

Purpose Treating solid tumors with cancer immunotherapy (CIT) can result in unconventional responses and overall survival (OS) benefits that are not adequately captured by Response Evaluation Criteria In Solid Tumors (RECIST) v1.1. We describe immune-modified RECIST (imRECIST) criteria, designed to better capture CIT responses. Patients and Methods Atezolizumab data from clinical trials in non-small-cell lung cancer, metastatic urothelial carcinoma, renal cell carcinoma, and melanoma were evaluated. Modifications to imRECIST versus RECIST v1.1 included allowance for best overall response after progressive disease (PD) and changes in PD definitions per new lesions (NLs) and nontarget lesions. imRECIST progression-free survival (PFS) did not count initial PD as an event if the subsequent scan showed disease control. OS was evaluated using conditional landmarks in patients whose PFS differed by imRECIST versus RECIST v1.1. Results The best overall response was 1% to 2% greater, the disease control rate was 8% to 13% greater, and the median PFS was 0.5 to 1.5 months longer per imRECIST versus RECIST v1.1. Extension of imRECIST PFS versus RECIST v1.1 PFS was associated with longer or similar OS. Patterns of progression analysis revealed that patients who developed NLs without target lesion (TL) progression had a similar or shorter OS compared with patients with RECIST v1.1 TL progression. Patients infrequently experienced a spike pattern (TLs increase, then decrease) but had longer OS than patients without TL reversion. Conclusion Evaluation of PFS and patterns of response and progression revealed that allowance for TL reversion from PD per imRECIST may better identify patients with OS benefit. Progression defined by the isolated appearance of NLs, however, is not associated with longer OS. These results may inform additional modifications to radiographic criteria (including imRECIST) to better reflect efficacy with CIT agents.