ASCO GU 2021: An Open-Label, Multicenter, Phase IIIb Study of Patients With Urinary Tract Carcinoma (STRONG): Final Analysis for Fixed-Dose Durvalumab Monotherapy (Module A)

( Advanced urothelial carcinoma has among the worst prognosis for tumors treated by genitourinary oncologists. Standard of care dictates that patients receive platinum-based induction chemotherapy. However, even with this treatment, rates of recurrence and disease progression are high and overall survival is quite short due to the development of chemotherapy resistance.

In the JAVELIN Bladder 100 study which was reported at ASCO 2020 Annual Meeting, the addition of avelumab, a PD-L1 directed therapy, as first-line maintenance to best supportive care demonstrated improvements in overall survival for patients who did not have disease progression during their initial cytotoxic chemotherapy induction. However, other agents have been examined. In particular, durvalumab (anti-PD-L1) has been approved for the treatment of metastatic urothelial carcinoma (mUC) after progression on platinum-based chemotherapy (CT). In a poster presentation at the 2021 ASCO Genitourinary Cancers Symposium (ASCO GU), Dr. Sonpavde and colleagues present data from the STRONG study (NCT03084471), aimed at understanding of long-term safety and efficacy of durvalumab in platinum and non-platinum pretreated patients, using a fixed-dose every 4 weeks.

To do so, the authors relied upon Module A of the phase IIIb STRONG study which investigated the safety of fixed-dose durvalumab (1500 mg, Q4W) in patients with both urothelial and nonurothelial urinary tract carcinoma who progressed on or after platinum/non-platinum CT.


The authors assessed the primary endpoint of so-called adverse events of special interest (AESI), those relating to an inflammatory or immune-mediated mechanism that may require interventions (eg, steroids/immunosuppressants), including immune-mediated adverse events (imAE). The authors included patients with AEs with onset date on or after the date of first dose and up to 90 days after study discontinuation. Secondarily, the authors examined serious AEs and overall survival (OS) with further exploratory endpoints including objective response rate (ORR) and disease control rate (DCR; with investigator assessment per RECIST 1.1).

The authors including 867 pts who received durvalumab monotherapy. In keeping with this patient population, the median age was 68.1 years and 80.0% were male. While 87.1% had an ECOG PS 0-1, 12.7% had ECOG PS 2.

The vast majority of included patients (96.3%) had urothelial histology, including urothelial variants and tumor PD-L1 expression was high (defined as ≥25%) in 41.4% of those with available data (239/577).

Over a median treatment and follow-up duration of 12.1 weeks (range 1-128) and 13.8 months (range 0.0-28.8), respectively, AESIs were seen among 50.5% of the cohort with grade 3 or greater AESI in 8%. Treatment-related death occurred in 9 patients.


As of March 31, 2020, 30.8% of patients were in survival follow-up and the median overall survival was 7.0 months (95% CI: 6.4-8.2). 1 and 2 year survival rates were 35.8% (95% CI: 32.5-39.2) and 20.2% (95% CI: 16.5-24.1), respectively. Median overall survival was somewhat higher among patients with high PD-L1 expression [9.3 mo (95% CI: 6.7-12.7) vs 6.5 mo (95% CI: 5.8-8.1]. Interestingly, the median overall survival was 7.0 months for patients with both urothelial and nonurothelial histology.


The authors conclude that fixed-dose durvalumab monotherapy administered every 4 weeks is convenient with an acceptable safety profile in this patient population.

Presented by: Guru Sonpavde, MD, Bladder Cancer Director, Dana Farber Cancer Center, Faculty, Harvard Medical School, Boston, Massachusetts

Co-Authors: Aurelien Marabelle, Yohann Loriot, Cora N. Sternberg, Jae-Lyun Lee, Aude Flechon, Guilhem Roubaud, Damien Pouessel, Vittorina Zagonel, Fabio Calabro, Giuseppe L. Banna, Sang Joon Shin, Francisco Emilio Vera Badillo, Thomas Powles, Eva Hellmis, Paulo Andre Palhares de Miranda, Ana Rita Lima, William Sawyer, Sebastien J. Hotte