Metastatic ccRCC Research Articles

Rhomboid-like 2 correlated with TME infiltration inhibits cuproptosis-related genes and drives malignant phenotype in clear cell renal cell carcinoma

The crosstalk between cuproptosis and the tumor immune microenvironment (TIME) is vital during clear cell renal cell carcinoma (ccRCC) malignant progression. However, the underlying molecular mechanisms regulate this cross-talk remain elusive. Through tailored machine learning, we analyze clinical ccRCC data from The Cancer Genome Atlas (TCGA) to explore the critical factors that regulate the interaction among cuproptosis, TIME, and tumor progression. We found that rhomboid-like 2 (RHBDL2), critical gene affecting this process, might inhibit cuproptosis-related genes (CRGs) and promotes ccRCC progression through the Wnt/β-catenin pathway. Next, knocking down RHBDL2 expression increased the cuproptosis-related genes ferredoxin 1 (FDX1) and lipoic acid synthase (LIAS) levels but reduced forkhead box P3 (FOXP3) levels and tumor growth in vivo and in vitro models. By employing HLY78, Wnt/β-catenin pathway activator, we rescued the expression of CRGs and the malignant proliferation and metastasis capacity in ccRCC cells with RHBDL2 knockdown. Mechanistically, RHBDL2 inhibits cuproptosis and promotes malignant progression of ccRCC through the Wnt/β-catenin pathway. Abnormal RHBDL2 expression may cause the suppressive TIME formation by regulating Treg-cell infiltration, thus triggering immune escape. In summary, our results indicated that RHBDL2 is an oncogene that induces tumorigenesis and targeting RHBDL2 may be novel therapeutic direction for metastatic ccRCC.

High RRM2 Correlates with Mitochondrial and Immune Responses in the Eosinophilic Subtype of Clear Cell Renal Cell Carcinoma.

Clear cell renal cell carcinoma (ccRCC), the predominant subtype of RCC, is distinguished by unique biological characteristics and heterogeneity, including eosinophilic and clear subtypes. Notwithstanding progress in therapy, immune checkpoint inhibitors (ICIs), and tyrosine kinase inhibitors (TKIs), the prognosis for individuals with metastatic ccRCC remains poor, presumably owing to metabolic alterations leading to mitochondrial dysfunction, which affects treatment response variability. We analyzed histological and immunohistochemical data from a cohort at Dalian Medical University's First Affiliated Hospital alongside RNA-sequencing transcriptome data from the TCGA database. Histologically, eosinophilic and clear ccRCC subtypes were evaluated using Kaplan-Meier and Cox proportional hazards models for survival analysis and prognosis. Differential gene expression (DEG) analysis and Gene Set Enrichment Analysis were performed to explore transcriptomic differences and relevant pathways. The study discovered substantial histological and molecular differences between the eosinophilic and clear cell subtypes of ccRCC. The eosinophilic subtype linked with frequent high-grade tumors (69.05% eosinophil vs 35.35% clear) and a poorer prognosis (HR=2.659, 95% CI:1.437-4.919, P=0.002). DEG analysis revealed distinct expression patterns among subtypes and identified a risk score signature that remained significant even after adjusting for clinical variables (HR=3.967, 95% CI: 1.665-9.449, P=0.002), showing less favorable survival in the high-risk group (P < 0.0001). RRM2 emerged as the most prognostic gene from this risk score, particularly in the eosinophilic subtype, alongside other clinical variables. By IHC, RRM2 shows high IHC score in eosinophilic compared to clear subtype (P=0.019). In addition, highly expressed RRM2 correlates with poor outcomes and is linked to mitochondrial genes, immunological pathways, and ICIs treatment. These findings show significant differences in prognosis between subtypes. RRM2 was the most prognostic gene from the discovered novel risk score signature associated with subtypes. Future research is essential to validate these insights and their therapeutic implications for ccRCC management.

Comparative Proteomics of ccRCC Cell Lines to Identify Kidney Cancer Progression Factors.

Clear cell renal cell carcinoma (ccRCC) is the most common type of kidney cancer, accounting for approximately 75% of kidney cancers. The objective of this study was to identify novel progression markers for ccRCC based on proteomics, with the goal of stage determination and early diagnosis of kidney cancer patients. We performed quantitative global proteomics coupled with Stable Isotope Labeling by Amino Acids in Cell Culture (SILAC) and high-resolution tandem mass spectrometry on kidney-derived cells, including HEK-293, 786-O (primary ccRCC), and Caki-1 (metastatic ccRCC) cells, to investigate the novel progression factors of ccRCC. In this study, a total of 1,106 proteins were quantified. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted for differentially expressed proteins (DEPs) that were increased in ccRCC cells compared to HEK-293 cells. Ultimately, 99 DEPs including 75 up-regulated and 24 down-regulated proteins, that were significantly altered in both ccRCC cells, were identified. Among DEPs, vimentin was identified as the most significantly changed protein. Its increased expression in ccRCC was verified through immunoblotting in ccRCC cell lines and immunohistochemistry in kidney tumors. From the global proteomics data detected in ccRCC, we propose 99 DEPs including vimentin as progression factors.

Distinct molecular profiles and shared drug vulnerabilities in pancreatic metastases of renal cell carcinoma.

Clear-cell renal cell carcinoma (ccRCC) is the most common origin of pancreatic metastases (PM). Distinct genomic aberrations, favorable prognosis, and clinical observations on high angiogenesis, and succeeding tyrosine kinase inhibitor (TKI) sensitivity have been reported in PM-ccRCC. However, no functional or single-cell studies have been conducted thus far. We recruited five PM-ccRCC patients and investigated the genomic, single-cell transcriptomic, and drug sensitivity profiles of their patient-derived cells (PDCs). The PM depicted both expected and novel genomic alterations. Further, the transcriptomics differed from both primary and metastatic ccRCC, with upregulations of the PI3K/mTOR and - supporting the clinical observations - angiogenesis pathways. Data integration at pathway level showed that transcriptomics explained drug sensitivities the best. Accordingly, PM-ccRCC PDCs shared sensitivity to many PI3K/mTOR inhibitors. Altogether, we show distinct genomic and transcriptomic signatures in PM-ccRCC, highlight the superiority of transcriptomics in interpreting drug sensitivities, and encourage the use of TKIs and PI3K/mTOR inhibitors in PM-ccRCC.

Emerging innovative treatment strategies for advanced clear cell renal cell carcinoma.

Dramatic advances in biological discoveries, since the 1990s, have continued to reshape the treatment paradigm of metastatic renal cell carcinoma (RCC). Von Hippel Lindau (VHL) gene alterations are associated with pro-angiogenic activity and are central to the pathogenesis of clear cell RCC (ccRCC), the most predominant histologic subtype of RCC. Antiangiogenic strategies revolving around this VHL/HIF/VEGF axis have been shown to improve survival in metastatic ccRCC. The discovery of immune checkpoints and agents that target their inhibition introduced a new treatment paradigm for patients with RCC. While initially approved as monotherapy, studies investigating immune checkpoint inhibitor combinations have led to their approval as the new standard of care, providing durable responses and unprecedented improvements in clinical outcome. Despite these advances, the projected 14390 deaths in 2024 from RCC underscore the need to continue efforts in expanding and optimizing treatment options for patients with metastatic RCC. This article reviews key findings that have transformed the way we understand and treat metastatic RCC, in addition to highlighting novel treatment strategies that are currently under development.

Regression of renal cell carcinoma by T cell receptor-engineered T cells targeting a human endogenous retrovirus

BackgroundWe discovered a novel human endogenous retrovirus (CT-RCC HERV-E) that was selectively expressed in most clear cell renal cell carcinomas (ccRCC) and served as a source of antigens for T...

Can Cytoreductive Nephrectomy Improve Outcomes of Nivolumab Treatment in Patients with Metastatic Clear-Cell Renal Carcinoma?

Background: This study aimed to investigate the effect of cytoreductive nephrectomy (CN) on the survival outcomes of nivolumab used as a subsequent therapy after the failure of at least one anti-vascular endothelial growth factor (VEGF) agent in patients with metastatic clear-cell renal-cell carcinoma (ccRCC). Methods: We included 106 de novo metastatic ccRCC patients who received nivolumab after progression on at least one anti-VEGF agent. Multivariate Cox regression analysis was performed to investigate the factors affecting survival in patients receiving nivolumab. Results: Of the 106 de novo metastatic ccRCC patients, 83 (78.3%) underwent CN. There were no statistical differences between the two groups in terms of age, gender, Eastern Cooperative Oncology Group (ECOG) score, tumor size, International Metastatic RCC Database Consortium (IMDC) risk group, number of previous treatment lines, first-line anti-VEGF therapy, or metastasis sites (p = 0.137, p = 0.608, p = 0.100, p = 0.376, p = 0.185, p = 0.776, p = 0.350, and p = 0.608, respectively). The patients who received nivolumab with CN had a longer time to treatment discontinuation (TTD) [14.5 months, 95% confidence interval (CI): 8.6-20.3] than did those without CN 6.7 months (95% CI: 3.9-9.5) (p = 0.001). The median overall survival (OS) was 22.7 months (95% CI: 16.1-29.4). The patients with CN had a median OS of 22.9 months (95% CI: 16.3-29.4), while those without CN had a median OS of 8.1 months (95% CI: 5.6-10.5) (p = 0.104). In the multivariate analysis, CN [hazard ratio (HR): 0.521; 95% CI: 0.297-0.916; p = 0.024] and the IMDC risk score (p = 0.011) were statistically significant factors affecting TTD; however, the IMDC risk score (p = 0.006) was the only significant factor for overall survival. Conclusions: Our study showed that the TTD of nivolumab was longer in metastatic ccRCC patients who underwent cytoreductive nephrectomy.

APOBEC3C-mediated NF-κB activation enhances clear cell renal cell carcinoma progression.

Renowned as the predominant form of kidney cancer, clear cell renal cell carcinoma (ccRCC) exhibits susceptibility to immunotherapies due to its specific expression profile as well as notable immune cell infiltration. Despite this, effectively treating metastatic ccRCC remains a significant challenge, necessitating a more profound comprehension of the underlying molecular mechanisms governing its progression. Here, we unveil that the enhanced expression of the RNA-binding protein DNA dC → dU-editing enzyme APOBEC-3C (APOBEC3C; also known as A3C) in ccRCC tissue and ccRCC-derived cell lines serves as a catalyst for tumor growth by amplifying nuclear factor-kappa B (NF-κB) activity. By employing RNA-sequencing and cell-based assays in ccRCC-derived cell lines, we determined that A3C is a stress-responsive factor and crucial for cell survival. Furthermore, we identified that A3C binds and potentially stabilizes messenger RNAs (mRNAs) encoding positive regulators of the NF-κB pathway. Upon A3C depletion, essential subunits of the NF-κB family are abnormally restrained in the cytoplasm, leading to deregulation of NF-κB target genes. Our study illuminates the pivotal role of A3C in promoting ccRCC tumor development, positioning it as a prospective target for future therapeutic strategies.

Construction of an autophagy-related genes risk model as predicting prognosis: BAG1 suppresses growth of clear cell renal cell carcinoma

BackgroundThe incidence of clear cell renal cell carcinoma (ccRCC) is increasing annually. While the cure rate and prognosis of early ccRCC are promising, the 5-year survival rate of patients with metastatic ccRCC is below 12%. Autophagy disfunction is closely related to infection, cancer, neurodegeneration and aging. Nevertheless, there has been limited exploration of the association between autophagy and ccRCC through bioinformatics analysis. MethodsA novel risk model of autophagy-related genes (ARGs) was constructed to predict the prognosis of patients with ccRCC and guide the individualized treatment to some extent. Relevant data samples were obtained from the TCGA database, and ccRCC-related ARGs were identified by Pearson correlation analysis, leading to the establishment of a risk model covering 10 ccRCC-related ARGs. Many indicators were used to assess the accuracy of the risk model. ResultsReceiver operating characteristic (ROC) curve analysis showed that the risk model had high accuracy, indicating that the risk model could predict the prognosis of ccRCC patients. Moreover, the findings revealed significant differences about immune and metabolic features in low- and high-risk groups. The study also found that BAG1 within the risk model was closely related to the prognosis of ccRCC and an independent risk factor. In vitro and in vivo experiments validated for the first time that BAG1 could suppress the proliferation, migration, and invasion of ccRCC. ConclusionThe construction of ARGs risk model, can well predict the prognosis of ccRCC patients, and provide guidance for individual therapy to patients. It was also found that BAG1 has significant prognostic value for ccRCC patients and acts as a tumor suppressor gene in ccRCC. These findings have crucial implications for the prognosis and treatment of ccRCC patients.

7 A Phase 1 study of fianlimab (anti–LAG-3) in combination with cemiplimab (anti–PD-1) in patients with advanced ccRCC

Abstract Background Concurrent blockade of lymphocyte-activation gene 3 (LAG-3) may enhance efficacy of anti–programmed cell death-1 (PD-1) therapies. We present safety and clinical activity data from a Phase 1 study (NCT03005782) in patients with clear cell renal cell carcinoma (ccRCC) treated with anti–LAG-3 (fianlimab) + anti–PD-1 (cemiplimab). Methods Patients with advanced or metastatic ccRCC who had received no more than two previous regimens of anti-angiogenic therapy who were anti–PD-(ligand[L])1-naïve (cohort 3) or anti–PD-(L)1-experienced with most recent dose within 3 months prior to screening (cohort 4) were eligible. All patients were to receive fianlimab 1600 mg + cemiplimab 350 mg intravenously every 3 weeks for up to 24 months. Tumor measurements were performed by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 every 6 weeks for 24 weeks, then every 9 weeks. The study objectives were to assess safety and antitumor activity of fianlimab + cemiplimab combination therapy in patients with ccRCC. Results Overall, 15 patients (median age: 64 years) each in cohorts 3 and 4 (total N=30) were enrolled and treated with fianlimab + cemiplimab as of November 1, 2022 data cutoff. For cohorts 3 and 4, 80% and 87% of patients were male, and 40% and 87% were White, respectively. All patients had prior cancer-related systemic therapy. In total, 60% and 93% of patients in cohorts 3 and 4 had ≥2 lines of prior therapies, respectively. For cohorts 3 and 4, median treatment duration was 27 weeks and 18 weeks, and median follow-up was 13 months and 24 months, respectively. Grade ≥3 treatment-emergent adverse events (TEAEs) occurred in 53% and 33% of patients in cohorts 3 and 4, respectively. Serious TEAEs occurred in 33% and 13% of patients in cohorts 3 and 4, respectively. Treatment-related AEs (TRAEs) were reported in 80% of patients in cohort 3 and 60% of patients in cohort 4. The most common TRAEs (any Grade) were rash (27%) and infusion related reaction (Grade 1 and 2; 27%) in cohort 3, and fatigue (20%) in cohort 4. Grade ≥3 TRAEs occurred in 27% of patients in cohort 3; there were no Grade ≥3 TRAEs in cohort 4. Treatment was discontinued due to any TEAE in three patients in cohort 3 and one patient in cohort 4. There was one death in cohort 3; a 79-year-old woman with a history of antiphospholipid syndrome died from complications of biopsy-proven ischemic colitis, which was attributed to study treatment. RECIST 1.1-based investigator-assessed objective response rate was 20% (3 partial responses [PRs]) in cohort 3 and 7% (1 PR) in cohort 4. The disease control rate was 60% and 73% in cohorts 3 and 4, respectively. Kaplan–Meier estimation of median progression-free survival was 4 months (95% confidence interval [CI] 1–10) in cohort 3 and 4 months (95% CI 1–7) in cohort 4. Durations of response were 4, 7, and 26 months in three responders in cohort 3, and 6 months in one responder in cohort 4. Conclusions Fianlimab + cemiplimab demonstrated promising signs of clinical activity with durable responses among patients who were anti–PD-(L)1-naïve (cohort 3) and anti–PD-(L)1-experienced (cohort 4), with an acceptable safety profile.

58 Tumor immune microenvironment determinants of response to Lenvatinib and aPD-1 blockade in clear cell renal cell carcinoma

Abstract Background Combinations of immune checkpoint blockade (ICB) and anti-angiogenesis tyrosine kinase inhibitors (TKI) are the mainstay of metastatic ccRCC front-line treatment, but heterogenous responses and lack of biomarkers strongly emphasizes the need to understand RCC-specific mechanisms of effective treatment-related anti-tumor immunity. Although prior work consistently highlights tumor associated macrophages (TAMs) in RCC prognosis and treatment response, TAM targeting has yet to experimentally assessed as a viable treatment sensitizer. Methods We therefore assessed the impact of TAM depletion using a clinical-grade colony stimulating factor receptor-1 inhibitor (CSF1Ri) on ICB or TKI sensitivity in a spontaneous mouse model of ccRCC with inducible kidney-specific Vhl, p53 and Rb1 deletions (KVpR). Mice were randomized to receive either no treatment, single agent Lenvatinib (TKI), aPD-1, or combinations with CSF1Ri. We longitudinally monitored a total of 307 tumors from 96 mice using magnetic resonance imaging (MRI) and collected responding and non-responding tumors for single cell RNA sequencing (scRNAseq) to elucidate the underlying mechanisms of response. Results Surprisingly we found that TAM depletion abolished aPD-1 response, with no effect on Lenvatinib response. ScRNAseq analyses suggest that CSF1R selectively depletes antigen presenting TAMs, leading to a striking loss of T cell infiltration. This suggests that TAMs, rather than dendritic cells as shown in other cancer types, may play a dominant role in eliciting T cells during aPD-1 therapy in RCC. On the other hand, Lenvatinib, which elicited a stronger T cell response than aPD-1, was associated with significant increases in cDC1 and plasma cells in responders, together suggesting that these two treatment modalities may operate through distinct antigen-presenting cells. Also unexpectedly, we found that both Lenvatinib and CSF1Ri induced severe intratumor hypoxia, which is typically associated with poor outcomes in most cancers. We identify a hypoxic niche-specific TAM subset that when abundant at baseline is predictive for poor response to ICB/TKI combos across multiple RCC trials, but post-treatment seems to capture hypoxia-mediated tumor cell death in responders in mouse and humans. We therefore wondered whether high levels of existing tumor hypoxia would exacerbate TKI-induced hypoxia leading to worst outcomes and found that in two novel RCC syngeneic models with high-baseline hypoxia, TKI indeed augments metastatic disease. Conclusions Our results offer mechanistic insight into the failure of CSF1R-based TAM depletion approaches in clinical trials and presents cautionary evidence against the use of hypoxia-inducing agents in tumors with high-baseline hypoxia. We show that TKI and ICB-induce distinct TME and hypoxia-related changes which require further study. More generally our study strongly emphasizes the importance of developing mechanism-guided clinical biomarkers. DOD CDMRP Funding: yes

First-line therapy for metastatic renal cell carcinoma: A propensity score-matched comparison of efficacy and safety

PurposeImmune checkpoint inhibitor (ICI)-based combination therapy is a standard systemic treatment for metastatic renal cell carcinoma (mRCC). Although differential pharmacologic action between ICI+ICI and ICI+tyrosine kinase inhibitor (TKI) combinations may affect outcomes, comparative studies using real-world data are few. MethodsWe retrospectively analyzed the records of 447 mRCC patients treated with 1st-line ICI-based combinations at multiple institutions between January 2018 and August 2023, and selected 320 patients diagnosed with clear cell RCC (ccRCC) for further study. Cohorts were matched using one-to-one propensity scores based on IMDC risk classification. Overall survival (OS), progression-free survival (PFS), objective response rates (ORRs), and treatment-related adverse events (TrAE) were compared. ResultsThe matching process yielded 228 metastatic ccRCC patients treated with ICI+ICI (n = 114) or ICI+TKI (n = 114). Median OS was 53 months (95%CI: 33–NA) in patients treated with ICI+ICI and was not reached (95%CI: 43–NA) with ICI+TKI (P = 0.24). Median PFS was significantly shorter for ICI+ICI (13 months, 95%CI: 7–25) than for ICI+TKI (25 months, 95%CI: 13–NA) (P = 0.047). There were no differences in second-line PFS for sequential therapy after 1st-line combinations of ICI+ICI or ICI+TKI (6 vs. 8 months, P = 0.6). There were no differences in ORR between the 2 groups (ICI+ICI: 51% vs. ICI+TKI: 55%, P = 0.8); the progressive disease (PD) rate was significantly higher in patients treated with the ICI+ICI combination (24% vs. 11%, P = 0.029). The rate of any grade TrAE was significantly higher in patients treated with ICI+TKI (71% vs. 85%, P = 0.016), but we found no differences in severe TrAE between the 2 groups (39% vs. 36%, P = 0.8). ConclusionsIn a matched cohort of real-world data, we confirmed comparable OS benefits between ICI+ICI and ICI+TKI combinations. However, differential clinical behaviors in terms of PFS, PD rates, and TrAE between ICI-based combinations may enrich clinical decision-making.

Diagnostic efficacy of [68Ga]Ga-NY104 PET/CT to identify clear cell renal cell carcinoma.

Most clear cell renal cell carcinoma (ccRCC) overexpresses carbonic anhydrase IX (CAIX). [68Ga]Ga-NY104 is a small-molecule PET agent selectively targeting CAIX. This study aims to assess the efficacy of [68Ga]Ga-NY104 PET/CT to identify ccRCC. Participants were prospectively recruited in the study (ClinicalTrials.gov: NCT05902377). They were further divided into two groups: group 1, patients with primary renal mass who were scheduled for surgery, group 2, patients with suspected/confirmed metastatic ccRCC. All patients underwent [68Ga]Ga-NY104 PET/CT. A total of 47 patients (mean age, 58.8years ± 13.5, 34 men) were recruited, including 20 patients in group 1 and 27 patients in group 2. The patient-level sensitivity, specificity, and accuracy of [68Ga]Ga-NY104 PET scan was 62%, 33%, 58% for group 1 and 95%, 100%, 96% for group 2. [68Ga]Ga-NY104 PET identified additional 26 disease regions in 67% (14/21) of patients that were previously unknown. The tumor uptake was correlated with immunohistochemical staining results. [68Ga]Ga-NY104 PET/CT has a high diagnostic efficacy for patients with metastatic ccRCC, while it might be of limited value in the diagnosis of primary ccRCC.

A CAIX Dual-Targeting Small-Molecule Probe for Noninvasive Imaging of ccRCC.

Carbonic anhydrase IX (CAIX), a zinc metal transmembrane protein, is highly expressed in 95% of clear cell renal cell carcinomas (ccRCCs). A positron emission tomography (PET) probe designed to target CAIX in nuclear medicine imaging technology can achieve precise positioning, is noninvasive, and can be used to monitor CAIX expression in lesions in real time. In this study, we constructed a novel acetazolamide dual-targeted small-molecule probe [68Ga]Ga-LF-4, which targets CAIX by binding to a specific amino acid sequence. After attenuation correction, the radiolabeling yield reached 66.95 ± 0.57% (n = 5) after 15 min of reaction and the radiochemical purity reached 99% (n = 5). [68Ga]Ga-LF-4 has good in vitro and in vivo stability, and in vivo safety and high affinity for CAIX, with a Kd value of 6.62 nM. Moreover, [68Ga]Ga-LF-4 could be quickly cleared from the blood in vivo. The biodistribution study revealed that the [68Ga]Ga-LF-4 signal was concentrated in the heart, lung, and kidney after administration, which was the same as that observed in the micro-PET/CT study. In a ccRCC patient-derived xenograft (PDX) model, the signal significantly accumulated in the tumor after administration, where it was retained for up to 4 h. After competitive blockade with LF-4, uptake at the tumor site was significantly reduced. The SUVmax of the probe [68Ga]Ga-LF-4 at the ccRCC tumor site was three times greater than that in the PC3 group with low CAIX expression at 30 min (ccRCC vs PC3:1.86 ± 0.03 vs 0.62 ± 0.01, t = 48.2, P < 0.0001). These results indicate that [68Ga]Ga-LF-4 is a novel small-molecule probe that targets CAIX and can be used to image localized and metastatic ccRCC lesions.

A phase II trial of sitravatinib plus nivolumab after progression on prior immune checkpoint inhibitor (ICI) in patients with metastatic clear cell renal cell carcinoma (ccRCC).

4542 Background: Sitravatinib, an oral multi-kinase inhibitor targeting VEGFR, TAM, and MET, has been shown to resensitize the tumor microenvironment to ICI by reducing immune-suppressive myeloid cells in metastatic ccRCC (Msaouel, Sci Transl Med 2022). ICI is the standard first-line (1L) treatment of metastatic ccRCC, and there is unmet need for improved treatment outcomes after progression on ICI. We hypothesized that sitravatinib plus nivolumab would revert an immunosuppressive tumor microenvironment (TME) to improve objective response rate (ORR) and survival in patients with metastatic ccRCC whose disease progressed on or after ICI. Methods: In this investigator-initiated, phase II, multicenter trial (NCT04904302), patients with progressive metastatic ccRCC after 1-2 lines of treatment were enrolled into three cohorts: Cohort A) progression on 1L nivolumab + ipilimumab, Cohort B) progression on 1L pembrolizumab + axitinib or 2L anti-PD-1 therapy after receiving 1L VEGF-targeted monotherapy, Cohort C) progression on 1L or 2L cabozantinib or lenvatinib +/- everolimus either before, after, or in combination with anti-PD-1 ICI. Starting dose of sitravatinib was 100 mg PO daily and nivolumab was 480 mg IV every 4 weeks. The co-primary endpoints were ORR [complete response (CR) + partial response (PR)] and disease control rate [DCR; CR, PR or stable disease (SD) at 24 weeks]. The study was designed to enroll 88 patients with an interim analysis for futility in each cohort using a BOP2 design, but it was terminated early due to discontinuation of sitravatinib development by the sponsor. Results: 14 patients were enrolled with 2 in cohort A, 6 in cohort B and 6 in cohort C. Most patients had IMDC intermediate risk disease (n=11, 78.6%), 7 patients had prior nephrectomy (50%), and sarcomatoid dedifferentiation was present in the tumors of 2 patients (7.1%). Across all cohorts, the ORR was 15.4% (2/13, 1 patient not evaluable) and DCR at 24 weeks was 35.7% (5/14). The 2 patients who experienced a PR were pre-treated with nivolumab + ipilimumab and pembrolizumab + axitinib. DCR at 24 months was 63% for Cohort A+B and 0% for Cohort C. After a median follow up of 11.9 months (mo), 10 patients had discontinued treatment (71.4%), all due to disease progression, and 6 patients had died (42.9%). Median progression free survival was 5.5 mo [ 95% CI 3.8 – not reached (NR)], and median overall survival was 13.3 mo (95% CI 8.77 – NR). Six patients (42.9%) experienced a grade 3-4 adverse event (AE) and 2 patients (14.3%) experienced an immune-mediated AE. Conclusions: In this small phase 2 trial with limited sample size due to early termination, sitravatinib plus nivolumab demonstrated a manageable safety profile and produced modest clinical benefit. The observed responses occurred in patients who did not receive prior treatment with cabozantinib or lenvatinib. Clinical trial information: NCT04904302 .

Health-related quality of life (HRQoL) with nivolumab (NIVO) subcutaneous (SC) or intravenous (IV) in patients (pts) with advanced or metastatic clear cell renal cell carcinoma (ccRCC) who have received prior therapy in the phase 3 CheckMate 67T trial.

4535 Background: NIVO IV has improved outcomes in multiple tumor types. Evolving treatment paradigms have created a need for administration options that address treatment burden and improve efficiencies of healthcare systems. In a phase 1/2 study (CheckMate 8KX), pts were highly satisfied with NIVO SC and preferred it over NIVO IV [Lonardi et al, ESMO 2022; Lonardi et al, SITC 2023]. CheckMate 67T (NCT04810078) is a multicenter, randomized, open-label, phase 3 study that demonstrated pharmacokinetic and objective response rate noninferiority of NIVO SC vs IV in pts with locally advanced or metastatic ccRCC [George et al, ASCO-GU 2024]. This exploratory analysis assessed non-inferiority of HRQoL between pts randomized to NIVO SC (n=248) vs NIVO IV (n=247) in CheckMate 67T. Methods: HRQoL was measured using patient-reported outcomes (PROs), FKSI-19 (kidney cancer-related HRQoL) and the EQ-5D-5L (pt’s health status). FKSI-19 total score (range 0-76, higher score better HRQoL)and EQ-5D-5L visual analogue scale (VAS) (range 0-100, higher score better health HRQoL) scores were evaluated longitudinally on-treatment visits with ≥10 pts per arm included in model [week 57]) using linear mixed models (constrained longitudinal data analysis), with least squares (LS) mean changes from baseline and differences in the LS mean between NIVO SC and NIVO IV assessed; non-inferiority of NIVO SC vs NIVO IV was evaluated by examining overall treatment differences for on-treatment visits relative to prespecified thresholds. Results: PRO data were available for 247 pts (99.6%) for NIVO SC and 245 pts (99.2%) for NIVO IV, with completion rates &gt;87% across instruments up to week 57 for both treatment arms. HRQoL was maintained over time for both NIVO arms for FKSI-19 total score and subscales and EQ-5D-5L VAS. NIVO SC was non-inferior to NIVO IV across FKSI-19 total score and subscales and EQ-5D-5L VAS (Table). Conclusions: These results demonstrate maintenance of HRQoL for pts with advanced or metastatic ccRCC while on treatment with NIVO, regardless of the mode of administration (SC or IV), supporting the use of NIVO SC as a new option to align with patient preferences. Clinical trial information: NCT04810078 . [Table: see text]

Increase in blood pressure in patients with metastatic kidney cancer treated with combination checkpoint inhibitor and vascular endothelial growth factor receptor tyrosine kinase inhibitor therapy.

e24128 Background: The combination therapy of an immune checkpoint inhibitor (ICI) with a vascular endothelial growth factor receptor tyrosine kinase inhibitor (VEGFR-TKI) is considered a first line treatment option for patients with metastatic clear cell renal cell carcinoma (ccRCC). TKI-induced hypertension is a well-known potential side effect with VEGFR-TKIs however little is known about the real-world increase in systolic blood pressure (SBP) and diastolic blood pressure (DBP) in patients with and without underlying hypertension treated with this combination therapy. Methods: A retrospective study was performed that included patients with metastatic ccRCC who were treated at the University of Florida Health Cancer Center between June 2019 and September 2022 who received treatment with the combination of an ICI and VEGFR-TKI. The data collected included history of hypertension, patients use of anti-hypertensive therapy at baseline, SBP and DBP prior to initiation of therapy and at approximately one month after initiation of treatment. Results: We identified a total of 29 patients who met the inclusion criteria for our study. The median age was 68 years old (IQR 61-72) while 25 patients (86%) were male and 4 (14%) were females. There were 27 patients (93%) who were treated with axitinib with pembrolizumab, while 1 (3%) was treated with cabozantinib with nivolumab, and 1 (3%) was treated with lenvatinib with pembrolizumab. Out of the 29 patients, 11 (38%) did not have hypertension prior to therapy while 18 (62%) did have baseline hypertension and were receiving at least one anti-hypertensive treatment. In those patients without baseline hypertension, the median baseline SBP was 113 and the median SBP after one month of treatment was 144 (p = 0.01). Conversely, those patients with baseline hypertension, the median baseline SBP was 122 and median SBP after one month of treatment was 148 (p = 0.003). In those without hypertension at baseline, the mean SBP increase after one month was 27.3% while in those with baseline hypertension the mean increase in SBP of 17.0%. Conclusions: Our study demonstrates that in a real-world population of patients with metastatic ccRCC there is a statistically significant elevation of both SBP and DBP when treated with the combination of an ICI and VEGFR-TKI and that in those patients without baseline hypertension and not on anti-hypertensive therapy at baseline, there is a more pronounced increase in blood pressure. This data should reinforce the need to have close monitoring of SBP and DBP during therapy, regardless of whether the patient has underlying hypertension or not, and may help guide anti-hypertensive therapy during kidney cancer treatment.

A phase 1/2, open-label, multicenter, dose escalation and cohort expansion study of the safety and efficacy of anti-CD70 allogeneic CRISPR-Cas9–engineered T cells (CTX131) in adult patients with relapsed or refractory solid tumors.

TPS2676 Background: CD70, a type II transmembrane protein and member of the tumor necrosis factor (TNF) receptor family, demonstrates high expression across multiple malignancies making it an attractive target for chimeric antigen receptor (CAR) T cell therapy. CD70 is expressed in 80% of clear cell renal cell carcinoma (ccRCC) and in 40-60% of cervical carcinoma (CC), esophageal carcinoma (EC), pancreatic adenocarcinoma (PAC), and pleural mesothelioma (PM) (1). CTX131 is a CD70-directed allogeneic CAR T cell investigational product manufactured ex vivo from healthy donor T cells using CRISPR/Cas9 technology. Genetic modifications in CTX131 include targeted insertion of a CD70-directed CAR construct, and targeted disruption of 5 loci: TRAC (to reduce risk of GvHD), B2M (to improve persistence in the allogeneic setting), CD70 (to reduce fratricide and improve anti-tumor function), TGFBR2 (to reduce immunosuppressive effect of TGFB in the tumor microenvironment), and Regnase-1 (to improve functional persistence) (2). Preclinical studies show the combination of TGFBR2 and Regnase-1 disruption in CTX131 works synergistically to enhance anti-tumor activity, inhibit tumor growth in xenograft mouse models, prolong survival, and increase central memory T cell populations (3). Methods: We are conducting a phase 1/2 study in patients (pts) with unresectable or metastatic ccRCC, CC, EC, PAC, and PM. Part 1 is a dose escalation with two separate cohorts, one for ccRCC pts and another for CC, EC, PAC, and PM pts. Part 1 ccRCC cohort began recruiting in 2023. Part 2 is a single-arm expansion of disease-specific cohorts. Key eligibility criteria include at least one prior line of standard treatment, ECOG status 0-1, evaluable disease per RECIST v1.1 (or modified RECIST1.1 for PM), adequate hematologic and organ function, and availability of tumor tissue for CD70 IHC. Key exclusion criteria include prior treatment with CD70-targeting agents and active CNS metastasis. Pts will receive standard lymphodepleting chemotherapy with fludarabine 30 mg/m2 and cyclophosphamide 500 mg/m2 daily x 3 days followed by CTX131 IV infusion at doses ranging from 30-900 million cells in 4 dose level cohorts. Redosing with CTX131 is permitted. For Part 1, the primary endpoint is DLTs with secondary endpoints including ORR, DOR, PFS, and OS. For Phase 2 the primary endpoint is ORR by IRC assessment. The trial is currently open with enrollment ongoing. 1. Flieswasser et. al. 2019. 2. Mai et. al. 2023. 3. Terrett 2023. Clinical trial information: NCT05795595 .

A phase I/II study of talazoparib and axitinib in patients with advanced clear cell renal cell carcinoma.

4541 Background: Targeting the VEGF pathway is a backbone therapeutic for patients with advanced clear cell renal cell carcinoma (ccRCC). Tumor and tissue hypoxia may also lead to DNA repair suppression and PARPs are key regulators of DNA damage and genomic maintenance which interact with HIF proteins. Pairing a potent VEGFR TKI with a selective PARP inhibitor (PARPi) may lead to improved outcomes in ccRCC patients. Methods: This was a phase I/II, investigator-initiated, single-center, open-label study (NCT04337970) of talazoparib plus axitinib in previously treated ccRCC patients. In the phase Ib dose escalation, patients must have been previously treated with a PD-1/PD-L1 inhibitor with no maximum lines of prior therapy, and those in dose expansion were required to have prior treatment with a PD-1/PD-L1 inhibitor and prior VEGFR TKI, with a maximum of 2 prior lines of therapy. Patients received escalating doses of talazoparib (0.5 mg, 0.75 mg and 1 mg daily) with axitinib (5 mg twice daily) in a 3+3 design, with primary endpoint of safety and tolerability. After establishing the recommended phase II dose (RP2D), a dose expansion cohort enrolled patients in a Simon two-stage design with a primary endpoint of objective response (ORR), and secondary endpoints including progression-free survival (PFS). Results: From 2020-2023, 23 ccRCC patients were enrolled and treated on study. In the dose escalation, 15 patients enrolled across all 3 dose levels and there were 2 observed DLTS (1 in dose levels 2 and 3). Both DLTs was due to a lack of minimum exposure to study drugs during cycle 1 due to treatment-related toxicities. The maximum tolerated dose and RP2D established was 1 mg talazoparib daily with axitinib 5 mg twice daily. In the phase II dose expansion portion, an additional 9 patients were enrolled to evaluate preliminary efficacy. In total, 13/14 patients treated at the RP2D discontinued therapy due to progressive disease. The objective response rate (ORR) was 7% (90% CI 0, 30), with 1 patient achieving a partial response and 12 patients achieving stable disease (86%). With a median follow-up of 13.2 months (R: 6.6 -29), the median PFS was 6.1 months (95% CI 3.5, 8.4) and median overall survival (OS) was 27 months (95% CI 12- NE). Across the study, 13 (56%) patients had at least one treatment-emergent AE of grade 3+, and 9 (39%) patients had at least one treatment-related AE of grade 3+. Most common grade 3+ AEs included diarrhea, nausea, and anemia. Conclusions: This is the first clinical study evaluating combination PARPi and VEGFR TKI in metastatic ccRCC patients. This study established the RP2D and MTD of combination talazoparib and axitinib and demonstrated a tolerable safety profile across all dose escalation cohorts. The study did not meet the pre-defined efficacy threshold for further enrollment per Simon stage two design. Exploratory efforts to evaluate this treatment approach with tissue biomarker data remain ongoing. Clinical trial information: NCT04337970 .

Papillary Renal Cell Carcinoma: Current Evidence and Future Directions

Papillary renal cell carcinoma (pRCC) comprises 15-20% of all patients with renal cell carcinoma (RCC). Although in the localized setting where pRCC appears to have better outcomes than clear cell RCC (ccRCC), patients with metastatic pRCC have significantly worse outcomes than patients with metastatic ccRCC. Because of the overall rarity of pRCC, there have been less research and clinical trials devoted to this subtype. Therefore, treatment of pRCC has generally been extrapolated from approved therapies for ccRCC. Recent data shows promise with newer tyrosine kinase inhibitors, and there is emerging evidence on their combination with immune checkpoint inhibitors. However, more dedicated clinical trials to pRCC are urgently needed, as response rates and outcomes still lag behind ccRCC. This review summarizes the pathophysiology, genetic features, the evolution of treatment approaches since the systemic cytokine era, and current challenges of managing pRCC.