Efficacy of Cabozantinib in Metastatic MiT Family Translocation Renal Cell Carcinomas.

BACKGROUND: MiT family translocation renal cell carcinoma (TRCC) is a rare and aggressive subgroup of renal cell carcinoma harboring high expression of c-MET. While TRCC response rates to VEGF receptor tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors are limited, efficacy of cabozantinib (a VEGFR, MET, and AXL inhibitor) in this subgroup is unclear. METHODS: We performed a multicenter, retrospective, international cohort study of patients with TRCC treated with cabozantinib. The main objectives were to estimate response rate according to RECIST 1.1 and to analyze progression-free survival (PFS) and overall survival (OS). RESULTS: Fifty-two patients with metastatic TRCC treated in the participating centers and evaluable for response were included. Median age at metastatic diagnosis was 40 years (IQR 28.5-53). Patients' IMDC risk groups at diagnosis were favorable (9/52), intermediate (35/52), and poor (8/52). Eleven (21.2%) patients received cabozantinib as frontline therapy, 15 (28.8%) at second line, and 26 (50%) at third line and beyond. The proportion of patients who achieved an objective response was 17.3%, including 2 complete responses and 7 partial responses. For 26 (50%) patients, stable disease was the best response. With a median follow-up of 25.1 months (IQR 12.6-39), median PFS was 6.8 months (95%CI 4.6-16.3) and median OS was 18.3 months (95%CI 17.0-30.6). No difference of response was identified according to fusion transcript features. CONCLUSION: This real-world study provides evidence of the activity of cabozantinib in TRCC, with more durable responses than those observed historically with other VEGFR-TKIs or ICIs.

Association of prior local therapy and outcomes with programmed-death ligand-1 inhibitors in advanced urothelial cancer.

OBJECTIVES: To compare clinical outcomes with programmed-death ligand-1 immune checkpoint inhibitors (ICIs) in patients with advanced urothelial carcinoma (aUC) who have vs have not undergone radical surgery (RS) or radiation therapy (RT) prior to developing metastatic disease. PATIENTS AND METHODS: We performed a retrospective cohort study collecting clinicopathological, treatment and outcomes data for patients with aUC receiving ICIs across 25 institutions. We compared outcomes (observed response rate [ORR], progression-free survival [PFS], overall survival [OS]) between patients with vs without prior RS, and by type of prior locoregional treatment (RS vs RT vs no locoregional treatment). Patients with de novo advanced disease were excluded. Analysis was stratified by treatment line (first-line and second-line or greater [second-plus line]). Logistic regression was used to compare ORR, while Kaplan-Meier analysis and Cox regression were used for PFS and OS. Multivariable models were adjusted for known prognostic factors. RESULTS: We included 562 patients (first-line: 342 and second-plus line: 220). There was no difference in outcomes based on prior locoregional treatment among those treated with first-line ICIs. In the second-plus-line setting, prior RS was associated with higher ORR (adjusted odds ratio 2.61, 95% confidence interval [CI]1.19-5.74]), longer OS (adjusted hazard ratio [aHR] 0.61, 95% CI 0.42-0.88) and PFS (aHR 0.63, 95% CI 0.45-0.89) vs no prior RS. This association remained significant when type of prior locoregional treatment (RS and RT) was modelled separately. CONCLUSION: Prior RS before developing advanced disease was associated with better outcomes in patients with aUC treated with ICIs in the second-plus-line but not in the first-line setting. While further validation is needed, our findings could have implications for prognostic estimates in clinical discussions and benchmarking for clinical trials. Limitations include the study's retrospective nature, lack of randomization, and possible selection and confounding biases.

Sequencing of PD-1/L1 Inhibitors and Carboplatin Based Chemotherapy for Cisplatin Ineligible Metastatic Urothelial Carcinoma.

PURPOSE: Current first line treatment options in patients with metastatic urothelial carcinoma unfit to receive cisplatin containing chemotherapy include PD-1/L1 inhibitors and carboplatin containing chemotherapy. However, the optimal sequencing of these therapies remains unclear. MATERIALS AND METHODS: We conducted a multicenter retrospective analysis. Consecutive cisplatin ineligible patients with metastatic urothelial carcinoma treated with first line carboplatin containing chemotherapy followed sequentially by second line PD-1/L1 inhibitor, or the reverse order, were included. Patient demographics, objective response, time to treatment failure for first line and second line therapy, interval between end of first line and initiation of second line treatment (Interval1L-2L) and overall survival were collected. Multivariate analysis was conducted to examine the association of sequencing on overall survival. RESULTS: In this multicenter retrospective study we identified 146 cisplatin ineligible patients with metastatic urothelial carcinoma treated with first line PD-1/L1 inhibitor therapy followed by second line carboplatin containing chemotherapy (group 1, 43) or the reverse sequence (group 2, 103). In the overall cohort median age was 72, 76% were men and 18% had liver metastasis. In both groups objective response rates were higher with carboplatin containing chemotherapy (45.6% first line, 44.2% second line) compared to PD-1/L1 inhibitors (9.3% first line, 21.3% second line). On multivariate analysis treatment sequence was not associated with overall survival (HR 1.05, p=0.85). Site of metastasis was the only factor significantly associated with overall survival (p=0.002). CONCLUSIONS: In this biomarker unselected cohort of cisplatin ineligible patients with metastatic urothelial carcinoma, PD-1/L1 inhibitor followed by carboplatin containing chemotherapy and the reverse sequence had comparable overall survival.

Immune checkpoint inhibitors in advanced upper and lower tract urothelial carcinoma: a comparison of outcomes.

OBJECTIVES: To compare clinical outcomes between patients with locally advanced (unresectable) or metastatic urothelial carcinoma (aUC) in the upper and lower urinary tract receiving immune checkpoint inhibitors (ICIs). PATIENTS AND METHODS: We performed a retrospective cohort study collecting clinicopathological, treatment, and outcome data for patients with aUC receiving ICIs from 2013 to 2020 across 24 institutions. We compared the objective response rate (ORR), overall survival (OS), and progression-free survival (PFS) between patients with upper and lower tract UC (UTUC, LTUC). Uni- and multivariable logistic and Cox regression were used to assess the effect of UTUC on ORR, OS, and PFS. Subgroup analyses were performed stratified based on histology (pure, mixed) and line of treatment (first line, subsequent line). RESULTS: Out of a total of 746 eligible patients, 707, 717, and 738 were included in the ORR, OS, and PFS analyses, respectively. Our results did not contradict the hypothesis that patients with UTUC and LTUC had similar ORRs (24% vs 28%; adjusted odds ratio [aOR] 0.73, 95% confidence interval [CI] 0.43-1.24), OS (median 9.8 vs 9.6 months; adjusted hazard ratio [aHR] 0.93, 95% CI 0.73-1.19), and PFS (median 4.3 vs 4.1 months; aHR 1.01, 95% CI 0.81-1.27). Patients with mixed-histology UTUC had a significantly lower ORR and shorter PFS vs mixed-histology LTUC (aOR 0.20, 95% CI 0.05-0.91 and aHR 1.66, 95% CI 1.06-2.59), respectively). CONCLUSION: Overall, patients with UTUC and LTUC receiving ICIs have comparable treatment response and outcomes. Subgroup analyses based on histology showed that those with mixed-histology UTUC had a lower ORR and shorter PFS compared to mixed-histology LTUC. Further studies and evaluation of molecular biomarkers can help refine patient selection for immunotherapy.

Une nouvelle place pour les biomarqueurs circulants dans le cancer du rein en 2024 ?

A new role for biomarkers circulating in kidney cancer in 2024?

B cells and the coordination of immune checkpoint inhibitor response in patients with solid tumors.

Immunotherapy profoundly changed the landscape of cancer therapy by providing long-lasting responses in subsets of patients and is now the standard of care in several solid tumor types. However, immunotherapy activity beyond conventional immune checkpoint inhibition is plateauing, and biomarkers are overall lacking to guide treatment selection. Most studies have focused on T cell engagement and response, but there is a growing evidence that B cells may be key players in the establishment of an organized immune response, notably through tertiary lymphoid structures. Mechanisms of B cell response include antibody-dependent cellular cytotoxicity and phagocytosis, promotion of CD4+ and CD8+ T cell activation, maintenance of antitumor immune memory. In several solid tumor types, higher levels of B cells, specific B cell subpopulations, or the presence of tertiary lymphoid structures have been associated with improved outcomes on immune checkpoint inhibitors. The fate of B cell subpopulations may be widely influenced by the cytokine milieu, with versatile roles for B-specific cytokines B cell activating factor and B cell attracting chemokine-1/CXCL13, and a master regulatory role for IL-10. Roles of B cell-specific immune checkpoints such as TIM-1 are emerging and could represent potential therapeutic targets. Overall, the expanding field of B cells in solid tumors of holds promise for the improvement of current immunotherapy strategies and patient selection.

Blood-based circulating biomarkers for prediction of immune-checkpoint inhibitors efficacy in renal cell carcinoma.

Immune checkpoint inhibitors (ICI)-based combinations have become the standard first-line treatment for advanced clear cell renal cell carcinoma (ccRCC). Despite significant improvements in survival and the achievement of sustained long-term responses, a subset of patients remains refractory to ICI, and most will eventually develop resistance. Thus, identifying predictive biomarkers for ICI efficacy and resistance is essential for optimizing therapeutic strategies. Up to now, tissue-based biomarkers have not been successful as predictive biomarkers in RCC. Circulating blood-based biomarkers offer a promising alternative. These biomarkers, including circulating immune cells, soluble factors, tumor-derived markers, and those based on metabolomics, are less invasive, offer reproducibility over time, and provide a comprehensive assessment of tumor biology and patient immune status, as well as allow dynamic monitoring during treatment. This review aims to evaluate the current evidence on the different candidate circulating biomarkers being investigated for their potential to predict ICI efficacy in RCC patients.

Safety and efficacy of nivolumab in elderly patients with metastatic clear cell renal cell carcinoma: Analysis of the NIVOREN GETUG-AFU 26 study.

INTRODUCTION: Immune checkpoint inhibitors are standard of care in metastatic renal cell carcinoma but their activity and safety in elderly patients is insufficiently explored. We evaluated outcomes of elderly patients with mRCC treated with nivolumab in the GETUG-AFU 26 NIVOREN phase 2 trial (NCT03013335) and conducted exploratory circulating biomarker analyses. METHODS: Patients with mRCC were treated with nivolumab after at least one antiangiogenic therapy. The main endpoint of this analysis was safety in patients ≥ 70 years old (y.o), as per the rate of treatment-related grade 3-5 events (TRAE). Secondary endpoints included overall response rate (ORR), progression-free survival (PFS), overall survival. Exploration of candidate biomarkers associated with aging included baseline circulating cytokines involved in inflammation, adhesion, immune checkpoints, angiogenesis (IL6, IL7, IL8, BAFF, CXCL13, VCAM-1, 4-1BB, VEGF). RESULTS: Of 720 patients, 515 were < 70 y.o and 205 ≥ 70 y.o. Patients ≥ 70 y.o exhibited numerically less IMDC poor risk disease (21.0% vs 26.9%), sarcomatoid component (4.9% vs 9.8%) or brain metastases (5.9% vs. 14.7%), but more previous treatment lines (≥ 2 in 54.1% vs 48.5%). TRAE were higher in patients ≥ 70 y.o (24.9% vs. 17.9%, p = 0.033). Respective ORR (19.2% vs. 22.1%) and median PFS (4.5 versus 3.0 months, HR 0.97 [95%CI 0.81-1.15]) were similar. Overall survival was shorter in patients ≥ 70 y.o (19.3 versus 26.9 months, HR 1.26 [95%CI 1.04-1.51]), but not significantly in a competitive risk model. Only V-CAM1 and 4-1BB were found to be increased in patients ≥ 70 y.o. CONCLUSIONS: Nivolumab displayed higher grade 3/4 TRAE but manageable toxicity in elderly patients, with sustained activity. Elderly patients did not display specific inflammatory or angiogenic circulating profiles.

Validation of the Lung Immune Prognostic Index (LIPI) as a prognostic biomarker in metastatic renal cell carcinoma.

BACKGROUND: The Lung Immune Prognostic Index (LIPI) is associated with immune checkpoint inhibitors (ICI) outcomes across different solid tumors, particularly in non-small cell lung cancer. Data regarding the prognostic and/or predictive role of LIPI in metastatic renal cell carcinoma (mRCC) are still scarce. The aim of this study was to evaluate whether LIPI could be predictive of survival in mRCC patients. METHODS: We used patient level data from three different prospective studies (NIVOREN trial: nivolumab; TORAVA trial: VEGF/VEGFR-targeted therapy (TT); CheckMate 214: nivolumab-ipilimumab vs sunitinib). LIPI was calculated based on a derived neutrophils/(leukocyte-neutrophil) ratio > 3 and lactate-dehydrogenase >upper limit of normal, classifying patients into three groups (LIPI good, 0 factors;LIPI intermediate (int), 1 factor;LIPI poor, 2 factors) and/or into two groups (LIPI good, 0 factors;LIPI int/poor, 1-2 factors) according to trial sample size. Primary and secondary endpoints were overall survival (OS) and progression-free survival (PFS). RESULTS: In the Nivolumab dataset (n = 619), LIPI was significantly associated with OS (LIPI-good 30.1 vs 13.8 months in the LIPI int/poor; HR= 0.47) and PFS (HR=0.74). In the VEGF/VEGFR-TT dataset (n = 159), only a correlation with PFS was observed. In the CheckMate214 dataset (n = 1084), LIPI was significantly associated with OS (nivolumab-ipilimumab OS LIPI good vs int/poor: HR=0.55, p < 0.0001; sunitinib: OS LIPI good vs int/poor: 0.38, p < 0.0001) in both treatment groups in univariate and multivariate analysis. CONCLUSIONS: Pretreatment-LIPI correlated with worse survival outcomes in mRCC treated with either ICI or antiangiogenic therapy, confirming LIPI's prognostic role in mRCC irrespective of systemic treatment used.

Meta-analysis of perioperative immunotherapy in renal cell carcinoma: Available, but the jury is still out.

INTRODUCTION: While surgical management of renal cell carcinoma (RCC) is curative for many patients, others may relapse and could benefit from adjuvant treatments. Immune checkpoint inhibitors (ICI) have been proposed as a potential adjuvant therapy for improving survival in these patients, but the benefit/risk ratio of ICI in the perioperative setting remains unclear. METHODS: A systematic review and a meta-analysis of phase III trials of perioperative ICI (anti PD1/PD-L1 alone or in combination with anti-CTLA4 agents) in RCC was conducted. RESULTS: The analysis included results from 4 phase III trials, comprising 3,407 patients. ICI did not show a significant increase in disease-free survival (Hazard Ratio [HR] 0.85; 95% confidence interval [CI] 0.69-1.04; p: 0.11) or overall survival [OS] (HR 0.73; 95% CI 0.40-1.34; p: 0.31). High-grade adverse events were more frequent in the immunotherapy arm (OR 2.65; 95% CI 1.53-4.59; p: <0.001), and high-grade treatment-related adverse events were 8 times more frequent in the experimental arm (OR: 8.07; 95% CI: 3.14-20.75; p: <0.001). Subgroup analyses showed statistically significant differences favoring the experimental arm in females (HR: 0.71; 95 CI 0.55-0.92; p: 0.009), in sarcomatoid differentiation (HR: 0.60 95% CI 0.41-0.89; p: 0.01), and PD-L1 positive tumors (HR HR: 0.74; 95% CI 0.61-0.90; p: 0.003). No significant effect was found in patients according to age, type of nephrectomy (radical vs. partial), and stage (M1 without evidence of disease vs. M0 patients). CONCLUSION: Our comprehensive meta-analysis generally suggests that immunotherapy does not confer a survival advantage in the perioperative setting for RCC, with the exception of one positive study. While the overall results are not statistically significant, individual patient factors and other variables may play a role in determining who benefits from immunotherapy. Therefore, despite the mixed findings, immunotherapy may still be a viable treatment option for certain patients, and further studies are needed to determine which patient subgroups would be most likely to benefit.

Efficacy and safety of cabozantinib rechallenge in metastatic renal cell carcinoma: A retrospective multicentric study.

BACKGROUND: Despite metastatic renal cell carcinoma (mRCC) expanded treatment options, disease progression ultimately occurs for most patients. Rechallenge may be a compelling strategy in a refractory setting. Cabozantinib is the standard of care in first and later lines of therapy, but its activity in rechallenge is unknown. METHODS: This retrospective study assessed the efficacy and safety of cabozantinib rechallenge, as defined by a second exposure after an interval of ≥3 months without treatment or ≥1 other treatment line, in patients with mRCC. The primary endpoint was median progression-free survival (PFS) at rechallenge. Secondary endpoints included overall survival, objective response rate, and safety at rechallenge. RESULTS: We included 51 mRCC patients who received cabozantinib in a rechallenge setting between 2017 and 2022. Median age at diagnosis was 54 years, 78% were male, 90% had clear cell mRCC, and 92% had prior nephrectomy. 15 patients (29%) were rechallenged after a pause in treatment, whereas 36 (70.6%) had ≥1 other treatment lines between first cabozantinib exposure (CABO-1) and rechallenge (CABO-2). Median PFS was 15.1 months (mo, 95% Confidence interval 11.2-22.1) at CABO-1 and 14.4mo (95%CI 9.8-NR) at CABO-2. Median overall survival was 67.6mo for CABO-1 (95% CI 52.2-NR) and 27.4mo for CABO-2 (95%CI 17.2-NR); objective response rate was 70.6% for CABO-1 and 60% for CABO-2. CABO-2 PFS was higher for patients with CABO-1 PFS > 12 months, and for those who discontinued CABO-1 because of toxicity, without statistical significance. There were no unexpected adverse events. CONCLUSIONS: Cabozantinib rechallenge is a feasible treatment option with potential clinical benefit for mRCC patients.

Frontline immune checkpoint inhibitor-based combination therapy in metastatic renal cell carcinoma patients with poor performance status.

BACKGROUND: Immune checkpoint inhibitor-based combination therapy (ICI-based combination) is a new standard of care for metastatic clear cell renal cell carcinoma (mRCC) in the frontline setting. Patients with poor performance status (PS) (≥2) were excluded from pivotal trials. Hence, the activity and safety of ICI-based combination therapy in this group of patients is still unknown. METHODS: We performed a multicentre retrospective study of PS ≥2 mRCC patients who received frontline ICI-based combination, either nivolumab-ipilimumab (NI) or pembrolizumab-axitinib (AP). Patients' characteristics, clinical outcomes, and toxicity were collected. We analysed overall response rate (ORR), median progression-free survival (mPFS), median overall survival (mOS) and grade ≥3 adverse events (G ≥ 3AEs). The association between the predictive biomarker IPI (immune prognostic index) and ORR/PFS/OS was also evaluated. RESULTS: We identified 70 mRCC patients with PS ≥2 treated with ICI-based combination across 14 institutions between October 2017 and December 2021, including 45 and 25 patients were treated with NI and AP, respectively. Median age at diagnosis was 63 years, 51 (73%) were male, only 17 (24%) had prior nephrectomy, 50 (71%) had synchronous metastatic disease at diagnosis, and 16 (23%) had brain metastases. Sixty-one (87%) and 9 (13%) patients had ECOG (Eastern Cooperative Oncology Group) PS 2 and 3, respectively, and 25 (36%) and 45 (64%) patients were intermediate and poor International Metastatic RCC Database Consortium (IMDC) risk, respectively. Among all, 91% were clear cell RCC, 7 patients had sarcomatoid features. At the time of the analysis (median follow-up 11.1 months), 41% patients were dead. Median PFS and mOS in the entire cohort were 5.4 months and 16.0 months, respectively; ORR was 31%. No significant differences in ORR, PFS, OS, or G ≥3AEs were seen between NI and AP. The intermediate and poor IPI groups were significantly associated with reduced ORR and shorter PFS. CONCLUSION: We report the first cohort of PS ≥2 mRCC patients treated with frontline ICI-based combination therapy. The survival outcomes in our cohort were inferior to that reported in pivotal trials. No significant differences in ORR, PFS, OS or toxicity were seen between NI and AP. Prospective real-world studies are needed to confirm these results.

Immunotherapy maintenance therapy for advanced urothelial carcinoma (aUC): a comprehensive review.

Immunotherapy has revolutionized the systemic treatment of solid tumors, including advanced urothelial carcinoma (aUC), providing durable responses with a favorable safety profile. Multiple immune checkpoint inhibitor agents have been approved in monotherapy in second-line setting, and for a selected group of chemo-naïve cisplatin-ineligible patients with high PD-L1 expression. Despite the incorporation of immunotherapy to the systemic treatment landscape of aUC, platinum-based chemotherapy remains the standard of care in frontline setting for vast majority of patients. Urothelial carcinoma is a chemosensitive disease with response rates of up to 50% to frontline chemotherapy. However, the response to chemotherapy is short lasting with vast majority of patients experiencing disease progression and death within months. In this context, maintenance therapy constitutes an attractive therapeutic strategy to maximize the time to treatment failure. Different cytotoxic and targeted agents have been investigated as maintenance therapy for aUC but have not shown an impact on survival. Avelumab has become the first and only drug to improve overall survival as maintenance therapy after frontline platinum-based therapy in aUC patients and the first drug to be approved in this setting. This article will review the rational for maintenance therapy, the different drugs investigated as maintenance therapy for aUC, and the impact of avelumab maintenance therapy as a new standard of care in the management of aUC.

Immune Checkpoint Inhibitor Combination Therapy versus Sunitinib as First-Line Treatment for Favorable-IMDC-Risk Advanced Renal Cell Carcinoma Patients: A Meta-Analysis of Randomized Clinical Trials.

BACKGROUND: Novel combination therapies have been shown to improve the outcomes of treatment-naive patients with locally advanced or metastatic renal cell carcinoma (aRCC). However, the optimal systemic therapy for aRCC of favorable risk has yet to be clarified. We aimed to evaluate the efficacy and safety of different immunotherapy (IO) combinations, either with another IO (IO-IO) or with an antiangiogenic (IO-TKI), versus sunitinib in the first-line setting in aRCC patients with favorable IMDC risk. METHODS: We conducted a systematic search for evidence in PubMed, Ovid MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials published up to February 2021. The GRADE approach was used to assess the quality of evidence. Survival hazard ratios were extracted for analysis in the favorable-risk aRCC subgroup (IMDC). A sensitivity analysis was performed excluding trials of combination therapy without TKI. RESULTS: Five randomized controlled phase III trials with a total of 1088 patients were included in the analysis. The studies compared different combinations versus sunitinib monotherapy. All clinical trials reported overall survival (OS), progression-free survival (PFS), and objective response rate (ORR) data. Four out of five trials reported complete response (CR). There was no difference in OS nor PFS between treatment arms in the IMDC favorable-risk subgroup analysis (OS: HR = 1.07, 95% CI = 0.81-1.41; PFS: HR = 0.74, 95% CI = 0.46-1.19). A benefit in ORR and CR was found for combination therapy vs. sunitinib (ORR: HR = 1.89, 95% CI = 1.29-2.76; CR: HR = 3.58, 95% CI = 2.04-6.28). In the sensitivity analysis, including only IO-TKI vs. sunitinib, no difference in OS was found; however, an advantage in PFS was observed (OS: HR = 0.99, 95% CI 0.69-1.43; PFS: HR = 0.60 (0.45-0.81). The safety profile reported is consistent with previous reports. We did not find differences in the incidence of any adverse event (AE) or of grade ≥3 AEs. CONCLUSION: This meta-analysis shows that combinations of IO-KI as first-line treatment in favorable-IMDC-risk aRCC improve PFS, ORR, and CR, but not OS, versus sunitinib.

Baseline circulating unswitched memory B cells and B-cell related soluble factors are associated with overall survival in patients with clear cell renal cell carcinoma treated with nivolumab within the NIVOREN GETUG-AFU 26 study.

BACKGROUND: The phase II NIVOREN GETUG-AFU 26 study reported safety and efficacy of nivolumab in patients with metastatic clear cell renal cell carcinoma (m-ccRCC) in a 'real-world setting'. We conducted a translational-research program to determine whether specific circulating immune-cell populations and/or soluble factors at baseline were predictive of clinical outcomes in patients with m-ccRCC treated with nivolumab within the NIVOREN study. METHODS: Absolute numbers of 106 circulating immune-cell populations were prospectively analyzed in patients treated at a single institution within the NIVOREN trial with available fresh-whole-blood, using dry formulation panels for multicolor flow cytometry. In addition, a panel of 14 predefined soluble factors was quantified for each baseline plasma sample using the Meso-Scale-Discovery immunoassay. The remaining patients with available plasma sample were used as a validation cohort for the soluble factor quantification analysis. Tumor immune microenvironment characterization of all patients included in the translational program of the study was available. The association of blood and tissue-based biomarkers, with overall survival (OS), progression-free survival (PFS) and response was analyzed. RESULTS: Among the 44 patients, baseline unswitched memory B cells (NSwM B cells) were enriched in responders (p=0.006) and associated with improved OS (HR=0.08, p=0.002) and PFS (HR=0.54, p=0.048). Responders were enriched in circulating T follicular helper (Tfh) (p=0.027) and tertiary lymphoid structures (TLS) (p=0.043). Circulating NSwM B cells positively correlated with Tfh (r=0.70, p<0.001). Circulating NSwM B cells correlated positively with TLS and CD20 +B cells at the tumor center (r=0.59, p=0.044, and r=0.52, p=0.033) and inversely correlated with BCA-1/CXCL13 and BAFF (r=-0.55 and r=-0.42, p<0.001). Tfh cells also inversely correlated with BCA-1/CXCL13 (r=-0.61, p<0.001). IL-6, BCA-1/CXCL13 and BAFF significantly associated with worse OS in the discovery (n=40) and validation cohorts (n=313). CONCLUSION: We report the first fresh blood immune-monitoring of patients with m-ccRCC treated with nivolumab. Baseline blood concentration of NSwM B cells was associated to response, PFS and OS in patients with m-ccRCC treated with nivolumab. BCA-1/CXCL13 and BAFF, inversely correlated to NSwM B cells, were both associated with worse OS in discovery and validation cohorts. Our data confirms a role for B cell subsets in the response to immune checkpoint blockade therapy in patients with m-ccRCC. Further studies are needed to confirm these findings.

REchallenge of NIVOlumab (RENIVO) or Nivolumab-Ipilimumab in Metastatic Renal Cell Carcinoma: An Ambispective Multicenter Study.

INTRODUCTION: Immune checkpoint inhibitors (ICI) have been approved for front-line therapy in metastatic renal cell carcinoma (mRCC). However, progressive disease often occurs and subsequent therapies are needed. ICI rechallenge may be an option, but there is a lack of data regarding efficacy and prognostic factors. We assessed efficacy of ICI rechallenge and factors associated with better outcomes. Patients and Methods. This ambispective multicenter study included 45 mRCC patients rechallenged with nivolumab ± ipilimumab between 2014 and 2020. Primary endpoint was investigator-assessed best objective response rate (ORR) for ICI rechallenge (ICI-2). Factors associated with ICI-2 progression-free survival (PFS) were evaluated with multivariate Cox models. RESULTS: ORR was 51% (n = 23) at first ICI therapy (ICI-1) and 16% (n = 7) for ICI-2. Median PFS was 11.4 months (95% CI, 9.8-23.5) and 3.5 months (95% CI, 2.8-9.7), and median overall survival was not reached (NR) (95% CI, 37.8-NR) and 24 months (95% CI, 9.9-NR) for ICI-1 and ICI-2, respectively. Factors associated with poorer ICI-2 PFS were a high number of metastatic sites, presence of liver metastases, use of an intervening treatment between ICI regimens, Eastern Cooperative Oncology Group performance status ≥2, and poor International Metastatic RCC Database Consortium score at ICI-2 start. Conversely, ICI-1 PFS >6 months was associated with better ICI-2 PFS. In multivariate analysis, there were only statistical trends toward better ICI-2 PFS in patients with ICI-1 PFS >6 months (p=0.07) and toward poorer ICI-2 PFS in patients who received a treatment between ICI regimens (p=0.07). CONCLUSION: Rechallenge with nivolumab-based ICI has some efficacy in mRCC. We identified various prognostic factors in univariate analysis but only statistical trends in multivariate analysis. Our findings bring new evidence on ICI rechallenge and preliminary but unique data that may help clinicians to select patients who will benefit from this strategy.

Activity of Systemic Treatments After Cabozantinib Failure in Advanced Metastatic Renal Cell Carcinoma.

BACKGROUND: Cabozantinib, a potent multityrosine kinases inhibitor (TKI), has demonstrated overall survival (OS) benefit over everolimus in patients previously treated with VEGFR TKI for metastatic Renal Cell Carcinoma (mRCC). The efficacy of systemic treatments after cabozantinib failure has not been investigated. MATERIALS AND METHODS: We conducted a retrospective study on patients receiving systemic treatment after cabozantinib failure in heavily pretreated patient with mRCC. We assessed Time to Treatment Failure (TTF), OS and objective response rate (ORR). RESULTS: Among 150 patients treated with cabozantinib in our institution, 56 (37.3%) received subsequent systemic therapy and were eligible for the analysis. IMDC prognostic group was good, intermediate and poor in 11 (19.6%), 24 (42.9%) and 11 (19.6%) patients, respectively. Cabozantinib was administered mainly as a second (41.1%), or third (33.9%) line treatment. axitinib or immune-checkpoint inhibitors were the subsequent treatment in 18 (34.8%) patients for each everolimus (n:16, 28.6%), other angiogenesis inhibitors (n:4, 7.1%) TTF and OS from subsequent systemic therapy after cabozantinib failure were 2.8 months (95%CI 1.9-3.7) and 7.7 months (95%CI 4.4-10.8), respectively. ORR was 8.7% and 2 patients with axitinib and 2 patients treated with Immune checkpoint inhibitors achieved a partial response. CONCLUSION: Overall, activity of systemic therapies after cabozantinib was limited.

Response and Outcomes to Immune Checkpoint Inhibitors in Advanced Urothelial Cancer Based on Prior Intravesical Bacillus Calmette-Guerin.

BACKGROUND: Immune checkpoint inhibitors (ICI) improve overall survival (OS) in patients with locally advanced, unresectable, or metastatic urothelial carcinoma (aUC), but response rates can be modest. We compared outcomes between patients with and without prior intravesical Bacillus Calmette-Guerin (BCG), who received ICI for aUC, hypothesizing that prior intravesical BCG would be associated with worse outcomes. PATIENTS AND METHODS: We performed a retrospective cohort study across 25 institutions in US and Europe. We compared observed response rate (ORR) using logistic regression; progression-free survival (PFS) and OS using Kaplan-Meier and Cox proportional hazards. Analyses were stratified by treatment line (first line/salvage) and included multivariable models adjusting for known prognostic factors. RESULTS: A total of 1026 patients with aUC were identified; 614, 617, and 638 were included in ORR, OS, PFS analyses, respectively. Overall, 150 pts had history of prior intravesical BCG treatment. ORR to ICI was similar between those with and without prior intravesical BCG exposure in both first line and salvage settings (adjusted odds radios 0.55 [P= .08] and 1.65 [P= .12]). OS (adjusted hazard ratios 1.05 [P= .79] and 1.13 [P= .49]) and PFS (adjusted hazard ratios 1.12 [P= .55] and 0.87 [P= .39]) were similar between those with and without intravesical BCG exposure in first line and salvage settings. CONCLUSION: Prior intravesical BCG was not associated with differences in response and survival in patients with aUC treated with ICI. Limitations include retrospective nature, lack of randomization, presence of selection and confounding biases. This study provides important preliminary data that prior intravesical BCG exposure may not impact ICI efficacy in aUC.

Association Between Sites of Metastasis and Outcomes With Immune Checkpoint Inhibitors in Advanced Urothelial Carcinoma.

BACKGROUND: Sites of metastasis have prognostic significance in advanced urothelial carcinoma (aUC), but more information is needed regarding outcomes based on metastatic sites in patients treated with immune checkpoint inhibitors (ICI). We hypothesized that presence of liver/bone metastases would be associated with worse outcomes with ICI. METHODS: We identified a retrospective cohort of patients with aUC across 26 institutions, collecting demographics, clinicopathological, treatment, and outcomes information. Outcomes were compared with logistic (observed response rate; ORR) and Cox (progression-free survival; PFS, overall survival; OS) regression between patients with/without metastasis beyond lymph nodes (LN) and those with/without bone/liver/lung metastasis. Analysis was stratified by 1st or 2nd+ line. RESULTS: We identified 917 ICI-treated patients: in the 1st line, bone/liver metastases were associated with shorter PFS (Hazard ratio; HR: 1.65 and 2.54), OS (HR: 1.60 and 2.35, respectively) and lower ORR (OR: 0.48 and 0.31). In the 2nd+ line, bone/liver metastases were associated with shorter PFS (HR: 1.71 and 1.62), OS (HR: 1.76 and 1.56) and, for bone-only metastases, lower ORR (OR: 0.29). In the 1st line, LN-confined metastasis was associated with longer PFS (HR: 0.53), OS (HR:0.49) and higher ORR (OR: 2.97). In the 2nd+ line, LN-confined metastasis was associated with longer PFS (HR: 0.47), OS (HR: 0.54), and higher ORR (OR: 2.79); all associations were significant. CONCLUSION: Bone and/or liver metastases were associated with worse, while LN-confined metastases were associated with better outcomes in patients with aUC receiving ICI. These findings in a large population treated outside clinical trials corroborate data from trial subset analyses.

Association of the Time to Immune Checkpoint Inhibitor (ICI) Initiation and Outcomes With Second Line ICI in Patients With Advanced Urothelial Carcinoma.

BACKGROUND: Early progression on first-line (1L) platinum-based therapy or between therapy lines may be a surrogate of more aggressive disease and poor outcomes in advanced urothelial carcinoma (aUC), but its prognostic role regarding immune checkpoint inhibitor (ICI) response and survival is unclear. We hypothesized that shorter time until start of second-line (2L) ICI would be associated with worse outcomes in aUC. PATIENTS AND METHODS: We performed a retrospective multi-institution cohort study in patients with aUC treated with 1L platinum-based chemotherapy, who received 2L ICI. Patients receiving switch maintenance ICI were excluded. We defined time to 2L ICI therapy as the time between the start of 1L platinum-based chemotherapy to the start of 2L ICI and categorized patients a priori into 1 of 3 groups: less than 3 months versus 3-6 months versus more than 6 months. We calculated overall response rate (ORR) with 2L ICI, progression-free survival (PFS) and overall survival (OS) from the start of 2L ICI. ORR was compared among the 3 groups using multivariable logistic regression, and PFS, OS using cox regression. Multivariable models were adjusted for known prognostic factors. RESULTS: We included 215, 215, and 219 patients in the ORR, PFS, and OS analyses, respectively, after exclusions. ORR difference did not reach statistical significance between patients with less than 3 months versus 3-6 months versus more than 6 months to 2L ICI. However, PFS (HR 1.64; 95% CI 1.02-2.63) and OS (HR 1.77; 95% CI 1.10-2.84) was shorter among those with time to 2L ICI less than 3 months compared to those who initiated 2L ICI more than 6 months. CONCLUSION: Among patients with aUC treated with 2L ICI, time to 2L ICI less than 3 months was associated with lower, but not significantly different ORR, but shorter PFS and OS compared to 2L ICI more than 6 months. This highlights potential cross resistance mechanisms between ICI and platinum-based chemotherapy.