NECTIN4 Amplification Is Frequent in Solid Tumors and Predicts Enfortumab Vedotin Response in Metastatic Urothelial Cancer.

PURPOSE: The anti-NECTIN4 antibody-drug conjugate enfortumab vedotin (EV) is approved for patients with metastatic urothelial cancer (mUC). However, durable benefit is only achieved in a small, yet uncharacterized patient subset. NECTIN4 is located on chromosome 1q23.3, and 1q23.3 gains represent frequent copy number variations (CNVs) in urothelial cancer. Here, we aimed to evaluate NECTIN4 amplifications as a genomic biomarker to predict EV response in patients with mUC. MATERIALS AND METHODS: We established a NECTIN4-specific fluorescence in situ hybridization (FISH) assay to assess the predictive value of NECTIN4 CNVs in a multicenter EV-treated mUC patient cohort (mUC-EV, n = 108). CNVs were correlated with membranous NECTIN4 protein expression, EV treatment responses, and outcomes. We also assessed the prognostic value of NECTIN4 CNVs measured in metastatic biopsies of non-EV-treated mUC (mUC-non-EV, n = 103). Furthermore, we queried The Cancer Genome Atlas (TCGA) data sets (10,712 patients across 32 cancer types) for NECTIN4 CNVs. RESULTS: NECTIN4 amplifications are frequent genomic events in muscle-invasive bladder cancer (TCGA bladder cancer data set: approximately 17%) and mUC (approximately 26% in our mUC cohorts). In mUC-EV, NECTIN4 amplification represents a stable genomic alteration during metastatic progression and associates with enhanced membranous NECTIN4 protein expression. Ninety-six percent (27 of 28) of patients with NECTIN4 amplifications demonstrated objective responses to EV compared with 32% (24 of 74) in the nonamplified subgroup (P < .001). In multivariable Cox analysis adjusted for age, sex, and Bellmunt risk factors, NECTIN4 amplifications led to a 92% risk reduction for death (hazard ratio, 0.08 [95% CI, 0.02 to 0.34]; P < .001). In the mUC-non-EV, NECTIN4 amplifications were not associated with outcomes. TCGA Pan-Cancer analysis demonstrated that NECTIN4 amplifications occur frequently in other cancers, for example, in 5%-10% of breast and lung cancers. CONCLUSION: NECTIN4 amplifications are genomic predictors of EV responses and long-term survival in patients with mUC.

Changes to Primary End Points in Randomized Clinical Trials on Immune Checkpoint Inhibitors in Urothelial, Renal Cell, and Lung Cancers: A Systematic Review.

This systematic review investigates how often and to what extent primary end points are changed and reported in immune checkpoint inhibitor clinical trials.

A real-world retrospective analysis of the management of metastatic castrate-resistant prostate cancer in Ontario, Canada from 2010 - 2018.

PURPOSE: We sought to quantify mCRPC patient treatment patterns and survival across multiple lines of therapy after prior androgen-receptor-axis-targeted therapy (ARAT) failure. METHODS: Individuals diagnosed with prostate cancer between 2010 and 2018 were identified in the Ontario Cancer Registry (OCR). An algorithm was created to identify patients with mCRPC that was aligned to Prostate Cancer Clinical Trials Working Group 3 criteria (PCWG3) and validated with Canadian clinical experts. In the mCRPC setting, treatment patterns were assessed by line of therapy, and survival was calculated from treatment initiation until death or lost to follow-up. RESULTS: 64,484 men were diagnosed withprostate cancer in Ontario between 2010 and 2018with 5,588 men assessed to have mCRPC and 2,970 (53%) of those received first-line systemic treatment. Across the first-, second- and third-line of therapy, ARATs (abiraterone and enzalutamide) were the most used therapies. Survival for mCRPC patients treated with ARATs in first-, second- and third-line were 13.0 (95% CI, 11.6 - 14.5), 11.5 (95% CI, 10.1 - 13.4) and 8.9 (95% CI, 7.4 - 10.2) months, respectively. Survival for mCRPC patients treated with taxanes in first, second- and third-line were 16.7 (95% CI, 14.8 - 18.0), 11.3 (95% CI, 10.1 - 12.5) and 7.8 (95% CI, 6.5 - 10.6) months, respectively. No statistical difference in overall survival was found between taxanes and ARATs. CONCLUSION: In this analysis of a large retrospective cohort of Canadian men with mCRPC, we found that survival in patients treated with ARATs and taxanes was fairly similar across all lines of therapy. Importantly, this trend was maintained in ARAT-exposed patients, where sequential ARAT and taxanes offered similar survival. These data may help inform optimal sequencing of therapies in mCRPC.

Can Oncogenic Driver Alterations be Responsible for the Lack of Immunotherapy Efficacy in First-line Advanced Urothelial Carcinoma?

Urothelial carcinoma (UC) harbors many oncogenic alterations and the limited efficacy of first-line immunotherapy in this setting suggests that oncogenic alterations could have potential as a predictive biomarker for treatment decision-making. Antibody-drug conjugates (ADCs) may offer new avenues for biomarker-driven treatment in advanced UC, especially for patients with oncogenic alterations.

Complete response and survival outcomes in patients with advanced cancer on immune checkpoint inhibitors.

Aim: To evaluate overall survival in advanced cancer patients who achieved complete response (CR) with immune checkpoint inhibitor (ICI) therapy. Methods: This retrospective study included patients with advanced unresectable or metastatic cancer who received at least one cycle of palliative-intent ICI. Best overall response was used to define response groups. Results: 21 (7%) of 322 patients achieved CR. Multivariate analysis demonstrated that CR was independently associated with better overall survival compared with disease progression (hazard ratio: 0.012; 95% CI: 0.002-0.090) and stable disease (hazard ratio: 0.063; 95% CI: 0.009-0.464) as well as a nonsignificant trend toward better overall survival compared with partial response (hazard ratio: 0.169; 95% CI: 0.023-1.252) regardless of cancer type, ICI regimen or ICI line. Conclusion: Patients who achieved CR had longer survival compared with patients who did not achieve CR.

Primary results of STRONG: An open-label, multicenter, phase 3b study of fixed-dose durvalumab monotherapy in previously treated patients with urinary tract carcinoma.

BACKGROUND: Prior durvalumab (anti-PD-L1 agent) studies in platinum-refractory metastatic urothelial carcinoma evaluated a dose of 10 mg/kg administered every two weeks. The nonrandomised phase 3b STRONG study (NCT03084471) evaluated the safety and efficacy of fixed-dose durvalumab at a more convenient dosing schedule in a previously treated patient population, more similar to a real-world clinical setting. PATIENTS AND METHODS: 867 patients with urothelial or nonurothelial urinary tract carcinoma (UTC) who progressed on or after platinum or nonplatinum chemotherapy were treated with durvalumab 1500 mg every four weeks; 87% had an Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-1, and 13% had an ECOG PS of 2. The primary end-point was the incidence of adverse events of special interest (AESIs), including immune-mediated AEs (imAEs). Secondary and exploratory end-points included overall survival (OS), objective response rate (ORR) and disease control rate (at six and 12 months) (DCR). RESULTS: AESIs of any grade were reported in 51% of patients (8% grade ≥ 3). The incidence of imAEs was 11% (2% grade ≥ 3). The median OS was 7.0 months (95% confidence interval [CI]: 6.4-8.2) and ORR was 18% (95% CI: 14.8-20.6), with complete responses in 5% of patients and a DCR at six months of 19% (95% CI: 16.1-22.1). CONCLUSION: Fixed-dose durvalumab monotherapy every four weeks has an acceptable safety profile and yields durable clinical activity in previously chemotherapy-treated patients with UTC. Safety and efficacy are consistent with previous durvalumab studies and other anti-PD-1/PD-L1 agents in this setting. CLINICALTRIALS. GOV IDENTIFIER: NCT03084471https://clinicaltrials.gov/ct2/show/NCT03084471.

Adjuvant Immune Checkpoint Inhibition in Muscle-invasive Bladder Cancer: Is It Ready for Prime Time?

We discuss results from the Checkmate-274 and IMvigor010 trials on adjuvant immune checkpoint inhibitor (ICI) therapy in muscle-invasive bladder cancer (MIBC) with or without neoadjuvant chemotherapy (NAC), and conclude that adjuvant ICI (nivolumab but not atezolizumab) should be considered for patients with resected high-risk MIBC, especially for those who have received NAC.

A Systematic Review and Meta-analysis of Dual Therapy in Patients With Advanced Renal Cell Carcinoma of Favourable Risk.

OBJECTIVE: To define the impact of first-line dual therapy involving immune checkpoint inhibitors (ICI) on survival outcomes in patients with advanced renal cell carcinoma (aRCC) of International Metastatic RCC Database Consortium favourable-risk. MATERIALS AND METHODS: Systematic review of Medline, EMBASE, and Cochrane Central Register of Controlled trials were conducted to select all phase II/III randomized clinical trials involving first-line, palliative-intent dual therapy in aRCC patients of favourable-risk. Inverse-variance with random-effects model was used for meta-analysis. Sensitivity analysis with exclusion of immune checkpoint inhibitors (ICI)-ICI combination was conducted. Study outcomes were overall survival (OS) and progression free survival (PFS). RESULTS: Seven phase II/III randomized controlled trials (N = 1214) were included in the meta-analysis. There were no significant OS differences detected in the favourable-risk group on dual therapy in comparison to sunitinib monotherapy (HR 0.96, 95%CI 0.73-1.26, P = .79). Sensitivity analysis also did not show significant OS benefit when excluding ICI-ICI regimen (HR 0.99, 95%CI 0.69-1.43, P = .96). PFS was not shown to have significant benefit for dual therapy in the favourable-risk group (HR 0.75, 95%CI 0.50-1.13, P = .17), but it met statistical significance when ICI-ICI regimen was excluded from the analysis (HR 0.63, 95%CI 0.50-0.79, P <.001). CONCLUSION: There was no OS benefit when comparing dual therapy vs sunitinib monotherapy in aRCC favourable-risk group. Longer follow-up would be required to definitively detect potential OS benefit, if any. Careful patient-clinician discussion of alternative management options are required prior to initiating dual-therapy in all aRCC favourable-risk group.

Canadian consensus on TRK-inhibitor therapy for NTRK fusion-positive sarcoma.

Malignant sarcomas are rare accounting for <1% of all adult solid malignancies and approximately 11% to 13% of all pediatric malignancies. TRK-inhibitors have demonstrated robust and long-lasting responses in patients with NTRK fusion-positive solid tumors, including sarcoma. Access to these agents in many jurisdictions such as Canada remains limited. We undertook a modified Delphi consensus to articulate and convey the clinical importance of these agents for the Canadian sarcoma community. A systematic search of published and presented literature was conducted to identify clinical trials reporting outcomes on the use of TRK-inhibitors in relapsed/refractory NTRK fusion-positive sarcoma. Three main consensus questions were identified: (a) is there currently an unmet clinical need for systemic therapy options in relapsed/refractory sarcoma? (b) do TRK-inhibitors confer a clinical benefit to patients with NTRK fusion-positive sarcoma? (c) do phase I/II basket trials provide sufficient evidence to justify funding of TRK-inhibitors in NTRK fusion-positive sarcoma? Response rates to the first and second surveys were 57% (n = 30) and 42% (n = 22), respectively. There was strong agreement among the Canadian sarcoma community that there was unmet clinical need for effective systemic therapy options in relapsed/refractory sarcoma, that TRK-inhibitors are a safe and effective treatment option for patients with NTRK fusion-positive sarcoma, and that available phase I/II basket trials provide sufficient evidence to support funding of these agents in relapsed/refractory NTRK fusion-positive sarcoma. TRK-inhibitors are a safe and effective systemic therapy option for patients with relapsed/refractory NTRK fusion-positive sarcoma.

Treatment and Patient Selection for Patients with Metastatic Castration-resistant Prostate After Progression on Docetaxel and Abiraterone/Enzalutamide: When to Play Your CARD and When to Do Your PARP.

For patients with metastatic castration-resistant prostate cancer (mCRPC) progressing after an androgen receptor axis-targeted therapy and docetaxel, poly (ADP-ribose) polymerase (PARP) inhibitors and chemotherapy with cabazitaxel have shown promise. We address the trials for the two approaches and consider possible sequencing of these drugs. We suggest that only patients with a BRCA2 mutation should receive a PARP inhibitor, and docetaxel or cabazitaxel should be favored in the absence of BRCA2 alterations, provided the patient is naïve to these drugs.

Fibroblast Growth Factor Receptor 3 Mutation as a Prognostic Indicator in Patients with Urothelial Carcinoma: A Systematic Review and Meta-analysis.

BACKGROUND: Fibroblast growth factor receptor 3 (FGFR3) mutations have been implicated in urothelial tumorigenesis. FGFR3 inhibitors are being explored in clinical trials. OBJECTIVE: We aimed to study the association between FGFR3 mutations and survival in urothelial carcinoma. DESIGN SETTING AND PARTICIPANTS: We performed a systematic literature search of PubMed, Cochrane, Ovid, and Web of Science from January 1985 to October 2018. The search terms were as follows: targeted therapies, FGFR and its subtypes, urothelial, bladder, and cancer. We included case-control or cohort studies of FGFR3 mutations in urothelial carcinoma. We included studies reporting hazard ratios (HRs) and 95% confidence intervals (CIs) for outcomes comparing FGFR3 mutations with FGFR3 wild type. Two reviewers performed article selection. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We assessed heterogeneity among study-specific HRs using I 2 statistic. We used a random effect model to obtain HR and 95% CI for event-free survival (EFS), composed of recurrence-free and progression-free survival. Statistical tests were two sided. RESULTS AND LIMITATIONS: Eleven studies (seven retrospective and four prospective) comprising 2162 patients were included. Analysis was performed for two groups. The first group included 1651 patients with non-muscle-invasive (NMI) urothelial carcinomas (886 [53.6%] had FGFR3 mutations). Compared with FGFR3 wild type, FGFR3 mutation did not influence EFS (HR = 0.99, CI = 0.77-1.28, p =  0.96). There was no significant heterogeneity (I 2 = 25%). The second group included 511 patients with NMI and muscle-invasive (MI) urothelial carcinomas (151 [30%] had FGFR3 mutations). FGFR3 mutation was not prognostic (HR = 1.54, CI = 0.41-5.81, p =  0.52). There was heterogeneity (I 2 = 91%). CONCLUSIONS: There is no association between FGFR3 mutation and EFS in NMI urothelial carcinoma, and in NMI and MI urothelial carcinoma groups. PATIENT SUMMARY: Fibroblast growth factor receptor 3 (FGFR3) mutation is not associated with a worse survival outcome in urothelial carcinoma. This is important as FGFR inhibitors are emerging as a new treatment option.

Adjuvant Radiation Therapy After Radical Nephrectomy in Patients with Localized Renal Cell Carcinoma: A Systematic Review and Meta-analysis.

CONTEXT: Adjuvant radiation therapy has been recommended for patients at higher risk of relapse from renal cell carcinoma (RCC) to improve disease-free survival (DFS) and overall survival (OS) after radical nephrectomy. OBJECTIVE: To quantify the benefit of adjuvant radiation therapy. EVIDENCE ACQUISITION: A systematic review of electronic databases identified publications exploring the association between adjuvant radiation therapy and locoregional recurrence (LRR), DFS, and OS among patients after radical nephrectomy for early-stage RCC. Hazard ratios for DFS were weighted and pooled using the generic inverse variance and random effects model. Odds ratios for LRR, DFS, and OS at 5yr were weighted and pooled in a meta-analysis using Mantel-Haenszel random-effects modeling. EVIDENCE SYNTHESIS: Twelve studies comprising 1624 patients were included in the analysis. Ten studies were retrospective and two were randomized controlled trials. Adjuvant radiation therapy was delivered to 37% of patients. The median follow-up was 49mo. Adjuvant radiation therapy was not associated with better DFS or OS at 5yr, but was associated with less LRR. CONCLUSIONS: With the caveat that confounding by indication may result from pooling data from predominantly nonrandomized studies, adjuvant radiation after radical nephrectomy was not associated with improved DFS or OS but was associated with less LRR. PATIENT SUMMARY: Radiation therapy after resection of renal cell carcinoma with a high risk of relapse may reduce the risk of local recurrence but not the risk of disease recurrence or death after 5yr.