Assessment of eligibility criteria in renal cell carcinoma trials evaluating systemic therapy

OBJECTIVES

To characterise the restrictiveness of eligibility criteria in contemporary renal cell carcinoma (RCC) trials, using recommendations from the American Society of Clinical Oncology (ASCO)-Friends of Cancer Research (FCR) initiative.

METHODS

vPhase I-III trials assessing systemic therapies in patients with RCC starting between 30 June 2012 and 30 June 2022 were identified. Eligibility criteria regarding brain metastases, prior or concurrent malignancies, hepatitis B virus (HBV) or hepatitis C virus (HCV) infection, and human immunodeficiency virus (HIV) infection were identified and stratified into three groups: exclusion, conditional inclusion, and not reported. Descriptive statistics were used to determine the frequency of eligibility criteria. Fisher's exact test or chi-square test were used to calculate their associations with certain trial characteristics.

RESULTS

A total of 423 RCC trials were initially identified of which 112 (26.5%) had sufficient accessible information. Exclusion of patients with HIV infection, HBV/HCV infection, brain metastases, and prior or concurrent malignancies were reported in 74.1%, 53.6%, 33.0%, and 8.0% of trials, respectively. In the context of HIV and HBV/HCV infection, patients were largely excluded from trials evaluating immunotherapy (94.4% and 77.8%, respectively). In addition, brain metastases were excluded in trials assessing targeted therapy (36.4%), combined therapy (33.3%), and immunotherapy (22.2%). Exclusion of patients with prior or concurrent malignancies was less frequently reported, accounting for 9.1%, 8.3%, and 5.6% targeted therapy, combined therapy and immunotherapy trials, respectively.

CONCLUSION

A substantial proportion of RCC trials utilise restrictive eligibility criteria, excluding patients with fairly prevalent comorbidities. Implementing the ASCO-FCR recommendations will ensure resulting data are more inclusive and aligned with patient populations in the real-world.

Examining Exclusion Criteria in Advanced Prostate Cancer Clinical Trials: An Assessment of recommendations From the American Society Of Clinical Oncology and Friends of Cancer Research

PURPOSE

Eligibility criteria illustrate the characteristics of the study population and promote the safety of participants. However, overreliance on restrictive eligibility criteria may limit the generalizability of outcomes. As a result, the American Society of Clinical Oncology (ASCO) and Friends of Cancer Research (Friends) issued statements to curtail these challenges. In this study, we aimed to assess restrictiveness in eligibility criteria across advanced prostate cancer clinical trials.

MATERIALS AND METHODS

We identified all phase I, II, and III advanced prostate cancer clinical trials between June 30, 2012, and June 30, 2022, through Clinicaltrials.gov. We evaluated whether a clinical trial excluded, conditionally included, or did not report 4 common criteria: brain metastases, prior or concurrent malignancies, HIV infection, and hepatitis B virus (HBV)/hepatitis C virus (HCV) infection. Performance status (PS) criteria were recorded based on the Eastern Cooperative Oncology Group (ECOG) scale.

RESULTS

Out of 699 clinical trials within our search strategy, 265 (37.9%) trials possessed all the required data and were included in our analysis. The most common excluded condition of our interest was brain metastases (60.8%), followed by HIV positivity (46.4%), HBV/HCV positivity (46.0%), and concurrent malignancies (15.5%). Additionally, 50.9% of clinical trials only included patients with ECOG PS 0 to 1. HIV and HBV/HCV infection were exclusion criteria of 22 (80.8%) and 19 (73.1%) immunotherapy trials, respectively.

CONCLUSION

Patients with brain metastases, prior or concurrent malignancies, HIV infection, HBV/HCV infection, or low-functioning PS were overly restricted from participating in advanced prostate clinical trials. Advocating for broader criteria may ameliorate generalizability.

Association Between Time-of-Day of Immune Checkpoint Blockade Administration and Outcomes in Metastatic Renal Cell Carcinoma

BACKGROUND

Preclinical evidence demonstrating circadian rhythmicity within the immune system provides a rationale for hypothesis that immune checkpoint inhibitor (ICI) infusion time-of-day may serve as an actionable mechanism to improve outcomes. Herein, we explore the association between ICI time of infusion (TOI) and outcomes in metastatic renal cell carcinoma (mRCC).

METHODS

Data from patients with mRCC who received nivolumab or nivolumab/ipilimumab, in first- or second-line were retrospectively collected. Patients who received < 20% of infusions after 16:30 were assigned to the early TOI sub-cohort, while the rest were assigned to the late TOI sub-cohort. Clinical outcomes were compared across the 2 groups.

RESULTS

Among 135 patients included, 89 (65.9%) and 46 (34.1%) were assigned to early and late TOI sub-cohorts, respectively. Baseline characteristics were comparable across the 2 sub-cohorts. Objective response rate (ORR) was 36.0% with early TOI versus 29.5% with late TOI (P = .157). Median time to treatment failure (TTF) was 9.5 months in the early TOI sub-cohort versus 4.6 months in the late TOI sub-cohort with a hazard ratio (HR) of 1.405 (95% CI, 0.919-2.149; P = .11) in univariate analysis and 1.694 (95% CI, 1.064-2.698; P = .026) in multivariate analysis. Higher cut offs allocating patients into the late TOI sub-cohort yielded an incremental increase in the HR for TTF and overall survival (OS) that reached statistical significance.

CONCLUSIONS

In patients with mRCC, early TOI yielded a numerical increase in ORR, TTF and OS, with the TTF difference reaching significance in multivariate analysis. Prospective randomized studies are warranted to examine the impact of chronomodulation on outcomes with ICIs in mRCC.

Racial and ethnic differences in perceptions of germline or somatic DNA sequencing among patients with advanced prostate, urothelial, or kidney cancer

We sought to determine racial and ethnic differences in perceptions (quality of communication, expectations, and concerns) of germline or somatic DNA sequencing (genomic profiling). Patients with prostate, urothelial, or kidney cancer were surveyed using a questionnaire that assessed previous experience, beliefs, expectations, and concerns regarding genomic profiling. Descriptive statistics and chi-square tests were used to identify factors associated with patients' perceptions of genomic profiling. A total of 150 consecutive patients were enrolled. The majority were male (74%) with a mean age of 68 years old. Most patients underwent somatic testing (54%), 24% undertook germline testing, and 21% undertook both tests. Significant differences were found across racial and/or ethnicity concerning factors that could have influenced patients' decision to pursue genomic profiling, including ability to guide the type of treatment (White: 54.1% vs. other ethnic groups: 43.9%, p = 0.04) and potential to improve treatment response (White: 10.1% vs. other ethnic groups: 22.0%, p = 0.04). Other ethnic group of patients were more concerned about learning that the cancer was less treatable or aggressive (43.8% vs. 27.7%, p = 0.01) and anxious about what would be learnt from genomic profiling (34.4% vs. 21.3, p = 0.01) as compared to White patients. Our findings reinforce the importance of developing culturally tailored education to help patients participate actively in decisions about genomic profiling.

Characterization of papillary and clear cell renal cell carcinoma through imaging mass cytometry reveals distinct immunologic profiles

Objective

To characterize and further compare the immune cell populations of the tumor microenvironment (TME) in both clear cell and papillary renal cell carcinoma (RCC) using heavy metal-labeled antibodies in a multiplexed imaging approach (imaging mass cytometry).

Materials and methods

Formalin-fixed paraffin-embedded (FFPE) baseline tumor tissues from metastatic patients with clear cell renal cell carcinoma (ccRCC) and papillary renal cell carcinoma (pRCC) were retrospectively requisitioned from an institutional biorepository. Pretreated FFPE samples from 33 RCC patients (10 ccRCC, 23 pRCC) were accessioned and stained for imaging mass cytometry (IMC) analysis. Clinical characteristics were curated from an institutional RCC database. FFPE samples were prepared and stained with heavy metal-conjugated antibodies for IMC. An 11-marker panel of tumor stromal and immune markers was used to assess and quantify cellular relationships in TME compartments. To validate our time-of-flight (CyTOF) analysis, we cross-validated findings with The Cancer Genome Atlas Program (TCGA) analysis and utilized the CIBERSORTx tool to examine the abundance of main immune cell types in pRCC and ccRCC patients.

Results

Patients with ccRCC had a longer median overall survival than did those with pRCC (67.7 vs 26.8 mo, respectively). Significant differences were identified in the proportion of CD4+ T cells between disease subtypes (ccRCC 14.1%, pRCC 7.0%, p<0.01). Further, the pRCC cohort had significantly more PanCK+ tumor cells than did the ccRCC cohort (24.3% vs 9.5%, respectively, p<0.01). There were no significant differences in macrophage composition (CD68+) between cohorts. Our results demonstrated a significant correlation between the CyTOF and TCGA analyses, specifically validating that ccRCC patients exhibit higher levels of CD4+ T cells (ccRCC 17.60%, pRCC 15.7%, p<0.01) and CD8+ T cells (ccRCC 17.83%, pRCC 11.15%, p<0.01). The limitation of our CyTOF analysis was the large proportion of cells that were deemed non-characterizable.

Conclusions

Our findings emphasize the need to investigate the TME in distinct RCC histological subtypes. We observed a more immune infiltrative phenotype in the TME of the ccRCC cohort than in the pRCC cohort, where a tumor-rich phenotype was noted. As practical predictive biomarkers remain elusive across all subtypes of RCC, further studies are warranted to analyze the biomarker potential of such TME classifications.

Patients' Perceptions Regarding the Relevance of Items Contained in the Functional Assessment of Cancer Therapy Kidney Symptom Index-19

BACKGROUND

There is a lack of consensus regarding the optimal method of assessing health-related quality of life (HR-QOL) among patients with metastatic renal cell carcinoma (mRCC). This study explored the perceived relevance of items that make up the Functional Assessment of Cancer Therapy Kidney Symptom Index-19 (FKSI-19), as judged by patients with mRCC.

METHODS

This was a multinational cross-sectional survey. Eligible patients responded to a questionnaire composed of 18 items that assessed the perceived relevance of each item in the FKSI-19 questionnaire. Open-ended questions assessed additional issues deemed relevant by patients. Responses were grouped as relevant (scores 2-5) or nonrelevant (score 1). Descriptive statistics were collated, and open-ended questions were analyzed and categorized into descriptive categories. Spearman correlation statistics were used to test the association between relevance and clinical characteristics.

RESULTS

A total of 151 patients were included (gender: 78.1 M, 21.9F; median age: 64; treatment: 38.4 immunotherapy, 29.8 targeted therapy, 13.9 immuno-TKI combination therapy) in the study. The most relevant questions evaluated fatigue (77.5), lack of energy (72.2), and worry that their condition will get worse (71.5). Most patients rated blood in urine (15.2), fevers (16.6), and lack of appetite (23.2) as least relevant. Qualitative analysis of open-ended questions revealed several themes, including emotional and physical symptoms, ability to live independently, effectiveness of treatment, family, spirituality, and financial toxicity.

CONCLUSION

There is a need to refine widely used HR-QOL measures that are employed among patients diagnosed with mRCC treated with contemporary therapies. Guidance was provided for the inclusion of more relevant items to patients' cancer journey.

Implications of ethnicity among patients with metastatic renal cell carcinoma (mRCC) treated with nivolumab plus ipilimumab (nivo/ipi)

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Background: Existing literature has reported differences in clinical outcomes by ethnicity in patients receiving immune checkpoint inhibitors (Olsen et al Front Oncol 2021). We investigated real-world outcomes between Latinx and non-Latinx mRCC patients treated with first-line nivo/ipi within a safety-net healthcare system and at a tertiary care center in Southern California. Methods: We performed a retrospective analysis of mRCC patients who received nivo/ipi within the Los Angeles County Department of Health Services (DHS), a safety-net healthcare system, and the City of Hope Comprehensive Cancer Center (COH), a tertiary oncology center, between Jan. 1, 2015 and Dec. 31, 2021. Patients were identified using institutional databases and clinical data were compiled from electronic health records. Patients with pathologic diagnosis of mRCC, age > 18 years and receipt of nivo/ipi as first-line therapy were included. Progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method, log-rank test, and Cox proportional hazards model with adjustments for other covariates. Results: Of 94 patients, 66 (70%) were male, 90 (94%) had clear-cell histology, and 87 (93%) had IMDC intermediate/poor risk disease. Forty patients (43%) were Latinx. Fifty (53%) and 44 (47%) patients received their care at a tertiary care center and within a safety-net healthcare system, respectively. Most Latinx patients (95%) were treated at DHS, and most non-Latinx patients (89%) were treated at COH. Latinx patients were significantly older than non-Latinx patients (59.5 vs 55 years, p=0.008). IMDC risk classification, body mass index, history of nephrectomy, and number of comorbidities were similar between both groups. Pooled analysis by ethnicity demonstrated significantly shorter PFS in Latinx versus non-Latinx patients (10.1 vs 25.2 months, HR 3.61, 95% CI 1.96-6.66, p= <0.01). Adjusting for age, gender, IMDC risk classification, history of nephrectomy, and number of co-morbidities, multivariate analysis revealed a HR of 3.41 (95% CI 1.31-8.84; p=0.01). At a median follow up of 11.0 months, the median OS was not met in either arm at the time of data cutoff (NR vs. NR, HR 1.34, 95% CI 0.44-4.11). Conclusions: Compared to non-Latinx patients,Latinx patients demonstrated shorter PFS; no difference was observed in OS although these data were immature. As the majority of Latinx patients received their care at DHS, our data suggest that disparities in access to care may significantly contribute to differences in clinical outcomes of mRCC patients receiving nivo/ipi.

Impact of race and payer status on the choice of urinary diversion among patients with localized bladder carcinoma undergoing cystectomy

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Background: Prior studies have described significant disparities in the selection of urinary diversion (UD) in patients with localized bladder cancer undergoing cystectomy. Although the choice of UD has not been shown to impact oncologic outcomes, continent urinary diversions (CUD) are associated with lower rates of in-hospital complications and mortality, but higher costs (Farber NJ et al. Bladder Cancer 2018). Male gender, White race, and higher income have been associated with proportionally higher rates of CUD than patients from other races or those without private insurance (Barocas DA et al. Cancer 2014 and Rios EM et al. Urology 2020). Utilizing the California Office of Statewide Health Planning and Development (OSHPD) database, we investigated potential barriers to CUD in patients with bladder cancer undergoing radical cystectomy. Methods: The current procedural terminology (CPT) and the international classification of diseases (ICD)-9/10 codes were used to identify patients with bladder cancer undergoing radical cystectomy from Jan 1, 2012, through Dec 31, 2018. Type of UD and demographic data such as race and payer status were collected. Univariate and multivariable analyses were conducted to determine the association between demographic variables and CUD use. Results: In total, 9,342 patients who underwent radical cystectomy were identified, of which 3,061 had UD status noted. Of these, 13.2% (404/3061) were continent and 86.2% (2,657/3061) were incontinent diversions. CUD use was significantly higher in White patients (14.1%; 320/2276) compared to Asian (12.8%; 24/187), Hispanic (9.5%; 30/316) or Black (5%; 6/119) patients (P=0.01). Use of CUD was significantly higher in patients with private insurance (23.2%; 167/721) compared to those with Medicare (10.2%; 207/2023) or indigent (MediCal/Medicaid; 8.6%; 23/269; p<0.001) coverage. On multivariable analysis adjusting for comorbidities and care setting, Black (OR: 0.30, 0.13-0.69) and Hispanic (OR: 0.57, 0.38-0.86) race were associated with a lower probability of getting a CUD, while male patients (OR 1.88, 1.31-2.71) and those receiving care at academic centers (OR 3.10, 2.38-4.05) were more likely to receive a CUD. Payer status did not show a significant difference between the two procedures. Finally, the presence of chronic kidney disease represented a risk factor for not getting a CUD (OR: 0.61, 0.43-0.85), but not the presence of diabetes and frailty. Conclusions: Black or Hispanic race and female gender were associated with lower rates of CUD when controlling for other factors. We hypothesize that the higher costs for CUD, communication barriers, especially with non-English speakers, comorbidities, and a potential lack of cultural humility could lead to an unconscious bias from the healthcare team. Further research aimed at understanding and addressing these disparities is needed.

Spectrum and implications of activating BRAF alterations in advanced prostate cancer (aPC)

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Background: Activating genomic alterations (GA) in BRAF are rare in aPC and their impact on pathogenesis is poorly understood. However, emerging data suggest that these GA may represent clinically actionable targets (Fenor et al, Clin Transl Oncol, 2022). Using comprehensive genomic profiling (CGP) performed in a single commercial lab, we characterized the GA landscape of BRAF-activated tumors in aPC patients (pts). Methods: Tissue(N=15,864) and liquid (N=7,566) biopsies from aPC pts were profiled using FoundationOne CDx and FoundationOne Liquid CDx CGP assays, respectively. Each assay covers 324 cancer-related genes, including the full coding region of BRAF and introns 7-10, with additional sensitivity in exons 11-18 in the liquid assay. Activating GA were defined as hotspot missense mutations, in-frame indels in the kinase domain, or rearrangements (RE) that preserve the kinase domain. Tissue biopsies from non-aPC cancer types (N= 275,151) were used for comparison. Results: BRAF-activating GA were detected in 520/15,864 (3.3%) tissue biopsies: RE were the most common GA (243 samples, 1.5%), followed by K601E (101, 0.6%), and G469A (58, 0.4%). Median age of pts with BRAF-altered tumors was 69 (interquartile range 63-76), compared to 68 for BRAF wild-type (interquartile range 62-74). Rearrangement breakpoints occurred most frequently in intron 8 (37%), intron 9 (28%), intron 10 (20%), and intron 7 (13%). The most common RE were BRAF N-terminal truncations removing the auto-inhibitory domain (22%), SND1-BRAF fusions (13%), intragenic BRAF deletions of the auto-inhibitory domain (12%), and TMPRS22-BRAF fusions (5%). When studying cases with BRAF-activating GA compared to wild-type, we noted a larger proportion of CDK12 mutations (9.2% vs 5.2%, p=0.018), and a depletion of TMPRSS2-ERG fusions (11% vs 32%, p<0.0001), PTEN GA (17% vs 31%, p<0.0001), and APC GA (4.4% vs 8.9%, p = 0.018); alterations in AR occurred at similar rates (13% vs 13%, p=1.0). In liquid samples, overall BRAF GA were slightly less common (187/7566, 2.5%): 65 (0.9%) RE, 33 (0.4%) K601E, 12 (0.2%) G469A. Examining BRAF-altered samples across all cancer types, aPC had the highest proportions of RE (46%) and one of the lowest frequencies of V600E (0.1%). Conclusions: Activating BRAF alterations are detected in ~3% of aPC, with frequent BRAF-SND1 fusions. BRAF RE represent almost half of aPC BRAF GA, the highest fraction observed across a pan-tumor dataset. In addition, we detected a higher incidence of concurrent CDK12 GA and a lower relative frequency of concurrent PTEN, APC, and TMPRSS2-ERG GA. These findings suggest that genetic activation of BRAF in aPC pts may contribute to tumorigenesis and supports further clinical investigation of therapeutics targeting the MAPK pathway in this molecular subtype.

Impact of race and payor status on patterns of utilization of partial and radical nephrectomy in patients with localized renal cell carcinoma (RCC)

614

Background: Racial minorities experience intersecting forms of marginalization and suffer significant healthcare disparities. Prospective trials have shown similar outcomes with partial and radical nephrectomy among patients with localized RCC (Van Poppel et al Eur Urol 2011), and multiple studies suggest increasing use of the former technique (Breau et al Can J Urol 2020). We hypothesize that patients from minority groups, as well as those with non-private insurance, will have less access to this specialized procedure and therefore have a higher rate of radical nephrectomy. Methods: We utilized the California Office of Statewide Health Planning and Development (OSHPD) database that collects information from all inpatient admissions, emergency room visits and inpatient/outpatient procedures in the state. All patients undergoing nephrectomy (both partial and radical) were identified from Jan 1, 2012 to Dec 31, 2018 using CPT and ICD-9/10 codes to identify patients. Demographic data was collected with specific attention to race and payor status. Univariate and multivariate analyses were conducted to determine the association between demographic data and procedure type. Results: In total, 31,093 patients were identified; 57% were males, with a mean age of 58 years. Among these, 16,142 (51.9%), 8,645 (27.8%), 2,795 (9.0%), 2,032 (6.5%) and 1,479 (4.8%) were characterized as White, Hispanic, Asian, Black and other, respectively. Partial nephrectomy and radical nephrectomy were performed in 15,840 (50.9%) and 15,253 (49.1%) of patients. By race, partial nephrectomy was performed in 8,576 (53.1%), 4,107 (47.5%), 1,286 (46.0%), 1,124 (55.3%) and 747 (50.5%) of White, Hispanic, Asian, Black and other patients, respectively (p<0.001). Use of partial nephrectomy also differed among patients based on payor status, with rates of 6,800 (56.4%), 5,036 (43.9%), 1,817 (38.3%) and 2,187 (77.7%) among patients with private, Medicare, indigent coverage (e.g., MediCal or Medicaid) and other insurance, respectively (p<0.001). On multivariate analysis controlling for age, gender, comorbidities and frailty, race was independently associated with type of nephrectomy procedure. Conclusions: Our study confirms that race and payor status may have an influence on utilization of partial versus radical nephrectomy, with the highest rate of partial nephrectomies among Whites and patients with private insurance. Although there are multiple potential confounders (e.g., latency of diagnosis and resulting tumor size/complexity), it is possible that access to care may be an important driver of these disparities.

Evaluation of eligibility criteria in contemporary renal cell carcinoma based on ASCO-FCR recommendations

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Background: A consensus statement from the American Society of Clinical Oncology (ASCO) and Friends of Cancer Research (FCR) collaboration highlights the importance of expanding eligibility criteria in cancer trials to more accurately reflect the real-world population (Kim et al., Clin Cancer Res 2021). We sought to characterize use of overly restrictive eligibility criteria in renal cell carcinoma (RCC) trials in the context of ASCO-FCR recommendations. Methods: Studies containing the MeSH terms “(metastatic OR advanced OR stage IV or unresectable) AND (kidney cancer OR renal cell carcinoma OR renal cell cancer)” from June 30, 2012 to June 30, 2022 were identified on the ClinicalTrials.gov platform. Our search query’s inclusion criteria identified international studies examining adult patients aged ≥ 18 in phase I-III trials. Exclusion criteria comprised pan-cancer studies, trials involving localized treatments, radiation therapy, and prognostic tools. Descriptive statistics were used to characterize the frequency of restrictive eligibility criteria across studies, while Fisher’s exact test or chi-square test were utilized to determine the association between treatment type and exclusion criteria. Results: The content of 423 RCC trials were analyzed, of which 112 (26.5%) had adequate data available. 48 (42.9%), 44 (39.3%) and 18 (16.1%) studies examined combination therapy, targeted therapy, and immunotherapy, respectively. The presence of HIV positivity, HBV/HCV positivity, brain metastases, and concurrent malignancies accounted for the most frequently cited exclusionary criteria, seen in 83/112 (74.1%), 60/112 (53.6%), 37/112 (33.0%), and 9/112 (8.0%) studies respectively. Differences in the use of HIV positivity (p<0.001) and HBV/HCV positivity (p<0.001) as eligibility criteria were observed across classes of therapy (see Table). Conclusions: A significant proportion of RCC studies utilize overly restrictive eligibility criteria as highlighted by the ASCO-FCR joint statement. Appropriate broadening of eligibility criteria to incorporate patient populations mirroring a real-world setting will provide more useful data going forward. [Table: see text]

Prevalence of dietary modification and supplement use in patients with metastatic renal cell carcinoma (mRCC)

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Background: Mounting data suggests that dietary modification and supplement use, including probiotics, may modulate outcomes with immunotherapy in cancer therapy (Spencer CN et al. Science 2021; Dizman N et al. Nature Medicine 2022). For the first time, we sought to quantify the use of these measures among patients with metastatic renal cell carcinoma (mRCC). Methods: An online survey was administered by Kidney Cancer Research Alliance (KCCure), a non-profit patient advocacy group, between July 22 and Sept 22 to a patient mailing list (N=1,532). Only patients diagnosed with mRCC and under active systemic therapy were included for analysis in the current study. Select questions were directed at dietary modification patterns and supplement usage. Patients were additionally surveyed regarding out-of-pocket spending patterns related to supplement purchases and to what extent they shared information about their supplement intake with their physicians. The student's t-test and Chi-square test were used to compare sociodemographic characteristics between participants who did and did not report supplement intake. Results: Out of 1,062 patients with renal cell carcinoma who participated in this survey, 289 met the inclusion criteria (M:F, 145:143). The median age was 61. The majority of patients identified themselves as white (91%), were from the US (86.8%), and had completed a bachelor's degree (52.9%). 21.1%, 46.1%, and 32.6% lived in urban, suburban, and rural locations, respectively. The most common reported first-line treatments were nivolumab/ipilimumab (32.4%) and axitinib/pembrolizumab (13.1%). 22.4% of respondents reported spending >$100/month on supplements, and 8.3% reported spending >$250/mo. Dietary modifications following a cancer diagnosis were reported by 34.9% of respondents, out of which 19.8% followed the Mediterranean diet and 18.8% adopted a ketogenic diet. 50.8% of respondents reported supplement intake. The most widely utilized supplements were cannabidiol (CBD) oil/marijuana, probiotics, and Vitamin C, reported by 28.0%, 24.2%, and 18.6% of respondents, respectively. 83.4% of respondents noted that they consistently report supplement usage to their physicians. There were no statistically significant associations between supplement use and age, sex, living area, or education. Conclusions: A substantial proportion of patients with mRCC use dietary modification and supplements as an adjunct to their antineoplastic treatment. Interventions such as probiotic use and ketogenic diets, which are the subject of a prospective study in mRCC (NCT05119010; NCT05122546), may already be used by many patients. More careful attention to nutrition and supplement use in clinical trial candidates may minimize the impact of these potential confounders.

Association between time-of-day of the immune checkpoint inhibitor (ICI) infusion and disease outcomes among patients with metastatic renal cell carcinoma (mRCC)

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Background: Recent studies have suggested an association between the time-of-day of ICI infusions and disease outcomes, including progression free survival and overall survival, among patients with cancer. (Qian et al Lancet Oncology 2021). We sought to identify whether such an association exists in patients with mRCC receiving ICIs. Methods: Patients with mRCC treated with nivolumab alone, or in combination with ipilimumab, in either first- or second-line treatment were retrospectively identified. Patients who received <25% of infusions after 4:30 pm were assigned to the early time of infusion (TOI) sub-cohort while patients who received ≥ 25% of infusions after 4:30 pm were assigned to the late TOI sub-cohort. Objective response rate (ORR, per RECIST 1.1), time to treatment failure (TTF, defined as time from the date of first ICI infusion to time of treatment discontinuation), and overall survival (OS) were compared across the two groups using Cox proportional hazard models before and after adjustment for potential confounders (age, gender, line of treatment, IMDC risk, and histologic subtype). Results: A total of 145 mRCC pts (M:F,102:43) were included in the analysis. Median age was 64 (range 31-89) years, 81.4% had clear cell histology, and 75.9% had intermediate/poor risk disease. Early TOI sub-cohort included 110 (75.9%) patients while late TOI sub-cohort included 35 (24.1%) patients. Baseline characteristics were comparable across the two groups. Median OS for the entire cohort was 41.7 months (95% CI, 33.0 – Not reached [NR]), with a median TTF of 6.5 months (95% CI, 5.0 – 10.8). ORR was 32.7% in early TOI sub-group versus 25% in late TOI sub-group (p=0.60). Median TTF for the early TOI sub-cohort was 8.3 months (95% CI 6.0 – 12.6), as compared to 4.4 months (95% CI 2.1 - 10.8) among the late TOI group with a hazard ratio (HR) of 0.79 (95% CI, 0.50 – 1.25; p=0.32). Multivariate analysis showed a HR of 1.55 (95% CI, 0.98 – 2.57; p=0.06) after adjustment for potential confounders. The median OS was 46.3 months (95% CI, 32.2 – NR) in early TOI sub-cohort versus 41.7 months (95% CI, 16.7 – NR) in late TOI sub-group with a HR of 0.67 (95% CI 0.37 – 1.23; p=0.20) in univariate analyses and 0.61 (95% CI 0.33 – 1.15; p=0.13) in multivariate analyses. Conclusions: Our results demonstrated a numerical increase in ORR, TTF and OS with early TOI compared to late TOI, with the TTF difference approaching significance after adjustment for potential confounders. Larger randomized and controlled investigations are warranted to examine the impact of chronomodulation on the efficacy of ICIs in cancers, including mRCC.

Improved health-related quality of life (HR-QOL) with use of an online mindfulness tool in patients with metastatic renal cell carcinoma (mRCC) receiving immunotherapy (IO)

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Background: Previous randomized studies have shown the benefit of interventions to increase mindfulness in multiple cancer types, including prostate cancer (Chambers et al JCO 2017), but limited data exists in mRCC. We sought to determine the effect of an app-based mindfulness intervention on anxiety, fear of cancer progression (FCR), fatigue and HR-QOL in this population. Methods: Eligible patients had mRCC, were receiving IO, had measurable symptoms of anxiety or FCR, had a smartphone with internet access and had not participated in a mindfulness program in the past 5 years. Patients were recruited in Brazil across 7 private centers and one academic center in the US. We evaluated the Mindfulness-Based Cancer Survivorship Journey, a program within the Am Mindfulness smartphone app (AmDTx). Patients used AmDTx for 20-30 minutes each day for a minimum of 4 days per week over a period of 4 weeks. Patients were assessed at baseline (T1) and at weeks 2 (T2), 4 (T3) and 12 (T4) using the PROMIS-Anxiety, FCR-7, Brief Fatigue Inventory (BFI), and Functional Assessment of Chronic Illness Therapy-General (FACT-G). RM-ANOVA was used to test the effect of time on symptoms and on HR-QOL. Results: A total of 41 patients were recruited; median age was 59 (range, 36-79) and patients were predominantly male (70%), white (61%), married (75%) and well educated (65% had at least a college degree). Most patients were receiving nivolumab/ipilimumab (44%), nivolumab (22%) or axitinib/pembrolizumab (9%). Symptoms of anxiety significantly decreased from 21.6 + 4.8 to 12.5 + 5.1 (P=0.001). Similar findings were found for FCR (MT1=21.4 to MT4=13.5, P=0.001) and fatigue (MT1=32.0 to MT4=19.4, P=0.001). Notably, HR-QOL increased from 81.1 + 13.4 to 92.7 + 14.9 (P=0.001). No significant differences were identified based on disease characteristics or type of therapy. Conclusions: The current study suggests that smartphone-based mindfulness intervention could improve HR-QOL and decreased FCR, anxiety and fatigue. This low-cost, easily accessible intervention may provide an important alternative to in-person psychosocial support for patients with mRCC and should be assessed in randomized trials in this disease. Funding: Kure It Cancer Research: 2020 Barry Hoeven Memorial Kidney Cancer Research Grant (PI: C D Bergerot).

Assessment of eligibility criteria in advanced urothelial cancer (aUC) trials based on ASCO-FCR recommendations

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Background: American Society of Clinical Oncology (ASCO) and the Friends of Cancer Research (FCR) underscored the need to broaden eligibility criteria in cancer trials to increase patient accrual, expand access to investigational treatments, and enhance generalizability of study results (Kim et al., Clin Cancer Res 2021). While eligibility criteria intend to prioritize patient safety and define a specific study population, these criteria are often based on outdated standards and may not be reflective of real-world practice. Our study aimed to characterize the proportion of aUC trial eligibility criteria according to the ASCO-FCR statement. Methods: Protocols indexed on ClinicalTrials.gov with start dates from June 30, 2012 to June 30, 2022 were evaluated. MeSH terms used in our query were “(metastatic OR advanced OR stage IV OR unresectable) AND (bladder cancer OR upper tract urothelial carcinoma OR upper tract urothelial cancer)”. International studies enrolling patients aged 18 and over in phases I-III were included. Studies examining multiple cancer types as well as those involving localized treatments (e.g., surgery or ablation), radiation therapy, and prognostic tools were excluded. Analyses of eligibility criteria focused on those highlighted in the ASCO-FCR statement; descriptive statistics were used to define the frequency of eligibility criteria and chi-square and Fisher’s exact test were used to determine their association with treatment type. Results: Overall, 205 urothelial cancer trials were assessed, with 37 (18.0%) having publicly accessible data. Of these, 13 (35.1%) evaluated combination therapy, 11 (29.7%) evaluated immunotherapy, 8 (21.6%) evaluated targeted therapy, and 5 (13.5%) evaluated chemotherapy. HIV positivity, HBV/HCV positivity, brain metastases, and concurrent malignancies were found to be exclusion criteria in 89.2% (33/37), 56.8% (21/37), 35.1% (13/37), and 5.4% (2/37) of studies, respectively. While brain metastases, concurrent malignancies, and HBV/HCV positivity were found to be independent of the class of therapy, a statistically significant association was observed with HIV positivity. Specifically, trials evaluating combination therapy (100.0%), immunotherapy (100.0%) and targeted therapy (87.5%) more frequently included HIV positivity as an exclusion criterion as compared to chemotherapy trials (40.0%). Conclusions: A modest percentage of a UC studies from the last decade were observed to report overly restrictive eligibility criteria as defined by the ASCO-FCR statement. HIV positivity and HBV/HCV positivity were commonly identified exclusion criteria, despite limited evidence that these criteria significantly impact drug efficacy and tolerability. Reassessing and updating eligibility criteria will ensure that the resulting data is more reflective and inclusive of a real-world population.

Evaluation of eligibility criteria in advanced prostate cancer clinical trials based on ASCO-FCR recommendations

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Background: The American Society of Clinical Oncology (ASCO) and the Friends of Cancer Research (FCR) published a joint statement addressing clinical eligibility for characteristics lacking adequate representation in recent studies (Kim et al., Clin Cancer Res 2021). Herein, we aimed to identify the frequency of other potentially excessive exclusion criteria in the context of metastatic prostate cancer. Methods: The eligibility criteria of advanced prostate cancer studies with start dates between June 30, 2012 and June 30, 2022 were identified through Clinicaltrials.gov. MeSH (Medical Subject Headings) terms in our query were “(metastatic OR advanced OR stage IV OR unresectable) AND (prostate cancer OR prostate adenocarcinoma)”. Our study included trials conducted worldwide and examined patients aged 18 and over in phase I-III trials. To narrow the scope of study, trials including more than one cancer type (basket trials) as well as those focusing on radiation therapy were not included in the study. Descriptive statistics were used to determine the frequency of eligibility criteria while the Fisher’s exact test or chi-square test were performed to demonstrate association between type of treatment and exclusion criteria. Results: 265 of 699 (37.9%) clinical trials within the specified search had sufficiently available data for evaluation. Of these, 136 (51.3%), 51 (19.2%), 26 (9.8%), 20 (7.5%), 19 (7.2%), and 7 (2.6%) of trials investigated treatment with combination therapy, hormone therapy, targeted therapy, immunotherapy, radioligand therapy, and chemotherapy, respectively. The most common ASCO-FCR-cited exclusion criteria in the studies were brain metastases (161/265, 60.8 %), HIV positivity (123/265, 46.4%), HBV/HCV positivity (122/265, 46.0%), and concurrent malignancies (41/265, 16.6%). Statistically significant relationships were identified between type of treatment along with status of brain metastases, HIV, and HBV/HCV (p=0.011, <0.001, and 0.001, respectively. Conclusions: This study represents the first effort to analyze this specific subset of exclusion criteria in relation to type of treatment in advanced prostate cancer. Attention to the ASCO-FCR consensus statement may maximize patient representation in future studies and increase generalizability of data. [Table: see text]

Genomic and Transcriptomic Predictors of Response from Stereotactic Body Radiation Therapy in Patients with Oligoprogressive Renal Cell Carcinoma

Stereotactic body radiation therapy (SBRT) has been shown to be safe and effective for delaying systemic treatment change among patients with metastatic renal cell carcinoma (mRCC). In this study, we sought to assess the genomic signatures of patients with mRCC who underwent SBRT for oligoprogression. A total of 30 patients with oligoprogressive disease were identified, the majority of whom had clear cell renal cell carcinoma (83.3%) and were receiving first-line treatment (53.3%). Genomic and transcriptomic sequencing were available in 20 and 16 patients, respectively. Duration of systemic treatment (DOT) was categorized as that prior (DOT[P]) and subsequent (DOT[S]) to radiation treatment. The median DOT(P) and DOT(S) were 15.1 and 18.3 mo, respectively, with a median DOT(S)/DOT(P) ratio of 1.4. Patients who had a DOT(S)/DOT(P) ratio of ≥1 had increased expression in pathways related to cell proliferation and development. In contrast, among patients with a ratio of ≤1, the reactive oxygen species pathway was enriched. This study highlights the potential role of genomics and transcriptomics to refine radiation treatment selection in patients with mRCC. PATIENT SUMMARY: In this study, we looked at mutations and genomic expressions among kidney cancer patients who responded better to stereotactic body radiotherapy. We found that enriched expression of certain pathways might play a role in response to radiotherapy.

Perceptions of COVID-19 Vaccination in Patients with Genitourinary Cancers: A Survey Study

Since the approval of the COVID-19 vaccines, their safety and efficacy has been widely demonstrated in patients with cancer. However, there remain patients with reservations regarding vaccination. We aimed to assess genitourinary cancer patients' perceptions of the vaccines as well as barriers and influencers of decision-making through the completion of a questionnaire. While vaccine-associated concerns were observed, most patients with genitourinary cancers were willing to receive the vaccine. Moving forward, differing strategies could be considered to enhance patient education on the utility of vaccination in the setting of cancer and beyond.

Abstract 6293: Genomic characteristics of nivolumab/ipilimumab with or without CBM-588 supplementation in patients with metastatic renal cell carcinoma

Background: In a previous randomized phase I trial, addition of CBM-588 to the nivolumab/ipilimumab (N/I) regimen showed improved objective response rate, clinical benefit rate, and progression free survival compared to N/I alone in patients (pts) with metastatic renal cell carcinoma (mRCC; Meza et al., ASCO 2021). Furthermore, genomic alterations such as PBRM1 have been associated with clinical benefit to anti-PD-1 monotherapy in patients with mRCC (Miao et al., Science 2018). The primary aim of this study was to investigate tumor genomic characteristics according to treatment arms.

Methods: We retrospectively identified pts with mRCC who received N/I alone or with CBM-588 supplementation along with whole exome and transcriptome sequencing (Ashion Analytics). Responses were measured according to RECIST v1.1. A two-tailed Fischer’s exact test was performed to compare genomic characteristics across arms.

Results: In this study, 29 mRCC pts were randomized to receive N/I +/- CBM-588 and 21 (72%) pts (71% in N/I with CBM-588 arm and 29% N/I arm) had available genomic data. Within this cohort, the median age was 66.8 (range 46-90) and 71% of pts were male. Eleven (52.4%) pts had clear-cell histology and 10 (47.6%) pts had sarcomatoid features; 15 pts received N/I with CBM-588 and 6 pts received N/I alone. The most commonly mutated genes in the overall cohort were VHL (61.9%), PBRM1 (42.9%), and SETD2 (33.3%). Alterations in VHL, PBRM1, and SETD2 were seen in 66.7% vs. 73.3% (p=0.115), 50.0% vs. 40.0% (p=0.523) and 33.3% vs. 33.3% (p=0.686), in N/I vs. N/I with CBM-588 arm, respectively.

Conclusions: There was no significant difference observed in clinically relevant genomic features across study arms. The clinical benefit from CBM-588 appears to be independent of tumor genomic characteristics. More extensive investigations are needed to characterize the determinants of benefit from CBM-588 supplementation.

Citation Format: Daniela V. Castro, Nazli Dizman, Zeynep B. Zengin, Jasnoor Malhotra, Luis A. Meza, Ramya Muddasani, Ameish Govindarajan, Neal S. Chawla, Alex Chehrazi-Raffle, JoAnn Hsu, Paulo G. Bergerot, Cristiane D. Bergerot, Tanya B. Dorff, Yung Lyou, Sumanta K. Pal. Genomic characteristics of nivolumab/ipilimumab with or without CBM-588 supplementation in patients with metastatic renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6293.

A phase I trial to evaluate the biologic effect of CBM588 (Clostridium butyricum) in combination with cabozantinib plus nivolumab for patients with metastatic renal cell carcinoma (mRCC)

TPS4606

Background: Combination therapy with the immune checkpoint inhibitor (ICI) nivolumab (nivo) and the tyrosine kinase inhibitor cabozantinib (cabo) is a new standard of care for first line treatment of patients with clear cell mRCC. However, despite the improved clinical benefit obtained with this regimen, a subgroup of patients still presents with progressive disease as best response (Choueiri et al NEJM 2021). There is now evidence supporting the role of the gut microbiome in mediating ICI activity (Routy et al Science 2018) and certain bacterial species, such as Bifidobacterium spp. in predisposing clinical response in patients with mRCC receiving ICIs (Salgia et al Eur Urol 2020). Moreover, recent evidence from a phase I clinical trial suggests that the addition of CBM588, a live probiotic comprised primarily of Clostridium butyricum, can enhance clinical response in patients with mRCC receiving nivolumab plus ipilimumab without incurring added toxicity (Meza et al ASCO, 2021). Herein we present the study design of an ongoing phase I study evaluating the biological effect of CBM588 in combination with cabozantinib plus nivolumab in patients with mRCC. Methods: This is an open label, randomized, single institution phase 1 trial for patients with confirmed mRCC with clear cell, papillary, or sarcomatoid components, who have not received prior systemic therapy for metastatic disease. A total of 30 eligible patient will be randomized 1:2 to receive either cabo/nivo at the standard dose/schedule (40mg PO QD and 480mg IV /4wks, respectively) alone or with CBM588 dosed at 80mg PO bid. The primary objective of the study is to determine the biologic effect of CBM588 with cabo/nivo in the modulation of the gut microbiome. This will be done by assessing the changes in Bifidobacterium spp. abundance and Shannon index (a measure of microbiome diversity) in stool specimens. Stool will be collected for bacteriomic profiling at baseline and after 12 weeks of treatment. Metagenomic sequencing will be performed using previously published methods (Dizman et al Cancer Med 2020). Secondary objectives include determining the effect of CBM588 on (1) clinical efficacy, through overall survival, response rate, and progression-free survival; (2) systemic immunomodulation, through assessment of changes in circulating Tregs, circulating cytokines/chemokines, etc; and (3) toxicities. A two-group t-test with a one-sided type I error of 0.05 will be used to assess the study primary endpoint. Clinical trial information: NCT05122546 .

Transcriptomic profiling identifies genomic markers associated with benefit from stereotactic body radiation therapy (SBRT) in oligoprogressive metastatic renal cell carcinoma (mRCC)

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Background: Addition of SBRT to systemic therapy in oligoprogressive mRCC has been shown to prolong the duration of systemic treatment (Cheung et al Eur Urol 2021; De et al BJUI 2021). To date, the genomic predictors of benefit are unknown. We hypothesized that hypoxia-related genes would be associated with lesser benefit from SBRT. Methods: We retrospectively identified patients (pts) with mRCC who had oligoprogressive disease (progression of < 5 sites) while on systemic treatment and received SBRT without any systemic treatment change or interruption. Clinicopathologic characteristics, whole exome and transcriptome sequencing (Ashion Analytics) data were collected. Duration of systemic therapy (DOT) was quantified as systemic treatment duration prior to oligoprogression (DOT[P]) and after completion of SBRT (DOT[S]). The ratio of DOT[S]/DOT[P] was calculated and patients with a ratio ≥ 1.0 were considered to derive greater benefit from SBRT. The frequency of specific DNA alterations and RNA expression of pts above and below a DOT[S]/DOT[P] threshold of 1.0 was compared using a two-tailed Fischer’s exact and student’s t-test, respectively. Results: In this study, 23 mRCC pts who had oligoprogression during systemic treatment and received SBRT were identified. Within this cohort 16 pts (69.6%; M:F, 12:4) had available genomic data. Median age was 70 years and the most common histology was clear cell (87.5%). At the time of oligoprogression 11 pts (68.8%) were on immunotherapy, 4 pts (25.0%) were on targeted therapy. Median DOT[S] and DOT[P] were 12.6 months (range,0.7-46.3) and 13.4 months (range, 0.5-26.9), respectively, with a median DOT[S]/DOT[P] ratio of 1.4 (range,0.01-3.8). The most commonly mutated genes were VHL (56.3%), PBRM1 (37.5%), and SETD2 (37.5%). Alterations in VHL, PBRM1 and SETD2 were seen in 66.7% vs 42.9%, 33.3% vs 43.9%, and 44.4% vs 28.6% in patients with greater vs lesser benefit from SBRT, respectively (p≥0.05for each). Transcriptomic analysis was available in 9 pts and 1580 genes were noted to be differentially expressed between the groups (p < 0.05). Limiting scope to cancer genes in the COSMIC database, pts with lesser benefit from SBRT had higher expression of CDKN1B, CNBP, and FOXO3 whereas pts with greater benefit had higher expression of RNF43, POLD1 and PBRM1 (p < 0.05 for each). Gene set enrichment analysis showed a trend towards increased expression of hypoxia related genes in pts with lesser benefit. Conclusions: Our data align with existing studies supporting the role of SBRT in oligoprogressive mRCC. In addition, while clinical benefit from SBRT appears to be independent of DNA-level alterations, transcriptomic analysis revealed significant differences in gene expression. Hypoxia-associated signatures may be associated with lesser benefit from radiotherapy.

Characterization of the microbial resistome in a prospective trial of CBM588 in metastatic renal cell carcinoma (mRCC) offers mechanism for interplay between antibiotic (abx) use and immune checkpoint inhibitor (ICI) activity

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Background: The negative association between ICI response and abx therapy is well defined (Derosa et al Cancer Discov 2021). Paradoxically, a retrospective assessment of the live bacterial product (LBP) CBM588 in patients (pts) with advanced lung cancer showed improved outcome with ICIs when the combination of CBM588 and abx (as compared to CBM588 alone) was employed (Tomita et al Cancer Immunol Res 2020). We postulated that the microbial resistome (genes encoding antimicrobial resistance) could shift in a manner with CBM588 therapy that facilitated ICI response. Methods: Pts with newly diagnosed mRCC with clear cell and/or sarcomatoid histology and intermediate/high risk disease per IMDC criteria were randomized to nivolumab/ipilimumab (nivo/ipi) or nivo/ipi/CBM588 in a 1:2 ratio. Stool samples were collected at baseline and week 12. Whole-metagenome sequencing was performed to analyze stool microbiome composition. Abx resistance genes (RGs) were inferred using publicly available database (McArthur et al. Antimicrob Agents Chemother 2013), and groups of abx RGs for various classes of abx were characterized. Wilcoxon signed-rank test was used for comparison of abx RG abundance between baseline and week 12 in each treatment arm and in responders (R) and non-responders (NR). Results: The study enrolled 30 pts, with the final analysis including 29 eligible pts (median age: 66 years, M:F 21:8, nivo/ipi: 19 pts, nivo/ipi/CBM588:10 pts). Objective response was 20% and 58% in nivo/ipi and nivo/ipi/CBM588 arms, respectively. The overall abundance of abx RGs remained unchanged between baseline and week 12 in pts receiving nivo/ipi alone. In contrast, a decrease in abx RGs was observed in pts receiving nivo/ipi with CBM588 arm from baseline to week 12 (p = 0.042 in Rs; p = 0.078 in NRs). More specifically, nivo/ipi/CBM588 treatment led to a significant reduction in fosfomycin RGs and nitroimidazole (e.g., metronidazole) RGs in both pts with R (p = 0.019 and 0.042, respectively) and NR (p = 0.031 and p = 0.031, respectively). A multitude of other clinically relevant abx RGs were downregulated in pts receiving CBM588, including those mediating resistance to glycopeptide (e.g., vancomycin) and lincosamide (e.g., clindamycin) abx. Conclusions: In the first interrogation of the resistome in mRCC, we demonstrate that CBM588 decreases abx RGs associated with multiple commonly used classes of abx. Abx clear commensals and increase pathogenic (abx resistant) bacteria in the gut. Based on our data, we formulate the hypothesis that combining abx with CBM588 may decrease potentially pathobionts and favor butyrogenic species, thereby improving CPI response. Clinical studies using CBM588 with abx priming may be warranted. Clinical trial information: NCT03829111.

How to Treat Renal Cell Carcinoma

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With several newly approved regimens for RCC, cardiovascular risks must be considered during treatment selection.

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Although uncommon, toxicities associated with these systemic therapies can have shortterm and long-term implications.

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Although some toxicities may be lethal, others can be managed with early intervention.

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As further agents are developed, multidisciplinary expertise is needed to manage associated cardiovascular toxicities.

Front-Line Therapy for Metastatic Renal Cell Carcinoma: A Perspective on the Current Algorithm and Future Directions

Simple Summary

The treatment landscape of metastatic renal cell carcinoma has changed dramatically over the course of the last decade. The use of doublet immunotherapy or targeted therapy/immunotherapy regimens has become the standard of care. Herein, we outline the important elements and considerations in the treatment of renal cell carcinoma and explore prospective treatment options within this setting.

Abstract

Over the last decade, the treatment paradigm of metastatic renal cell carcinoma has rapidly evolved, with notable changes in the front-line setting. Combination therapies involving the use of either doublet therapy with immune checkpoint inhibitors or combination VEGFR-directed therapies with immune checkpoint inhibitors have significantly improved clinical outcomes, including prolonged overall survival and durable response to treatment. We aim to highlight the Food and Drug Administration-approved front-line therapy options, the navigation of treatment selection, and the future directions of metastatic renal cell carcinoma therapies.

Prospective assessment of a smartphone-app based mindfulness program for patients with metastatic renal cell carcinoma (mRCC)

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Background: mRCC is associated with high rates of distress, high levels of symptom burden, and broad impairments in quality of life. In the setting of localized breast cancer, a smartphone application directed at enhancing mindfulness has been developed from a Mindfulness-Based Cancer Recovery program demonstrated to mitigate these factors (Utkarsh et al. Digital Health 2021); we sought to determine if the benefit of a similar application could be translated to patients with mRCC. Methods: Patients were recruited across two sites in the US and Brazil, and were eligible for the study if they had been diagnosed with mRCC, were receiving immunotherapy, reported clinically-relevant anxiety, had a smart phone with internet access, were currently not engaging in meditation, and had not participated in a mindfulness program in the past 5 years. Patients were asked to participate in mindfulness app-based activities for 20-30 minutes each day guided by the Mindfulness-Based Cancer Survivorship Journey program within AM Mindfulness smartphone app (AmDTx™), for a minimum of 4 days per week, over a period of 4 weeks. The application leads the patient through exercises in guided meditation and suggestions for cancer/cancer symptom coping. Patients were assessed at baseline and 2-weeks after using the 4-week smartphone-app based intervention using the Fear of Cancer Recurrence-7 and Functional Assessment of Chronic Illness Therapy-General scales. Reported data is evaluated using paired t-tests with a p-value of < 0.05 considered significant. Results: A total of 23 patients have been recruited to date. Median age was 59 years old; most were male (52%), white/Caucasian (52%), married (69%) and college educated (82%), and primarily receiving treatment with nivolumab (34%) or nivolumab/ipilimumab (30%). The majority of patients (78%) expressed satisfaction and engaged with the intervention; however, a minority (13%) noted that the intervention reminded them of their cancer diagnosis, which was seen as a negative aspect. Preliminary analyses of data after two weeks of the intervention have demonstrated a statistically significant decreases in fear of cancer progression (mean differences: baseline = 22; week 2 = 18, p = 0.012) and increases in quality of life (mean differences: baseline = 77; week 2 = 85, p = 0.001) over time. Physical and emotional well-being also showed significant improvement over time. Complete data with 12 weeks of follow-up will be presented at the meeting. Conclusions: This is the first study to implement an evidence-based, smartphone-accessible psychosocial support tool among mRCC patients. After only two weeks, we noted significant improvements in the fear of cancer progression and quality of life. This preliminary data suggests that this type of low-cost, mobile-app based intervention was acceptable to patients and may be effective at addressing psychosocial distress

Characterization of aberrant alternative splicing landscape in patients with renal cell carcinoma (RCC)

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Background: Aberrant alternative splicing (AS) events have been implicated in the initiation and progression of various cancers; however, the detailed nature of their role in RCC is yet to be fully elucidated. Our study aims to characterize AS events in RCC tumors using a novel AS pipeline (Bisbee). Methods: We retrospectively identified patients (pts) with RCC who had tumor-normal whole exome sequencing and tumor whole transcriptome sequencing (GEMExtra, Ashion Analytics) performed as part of their routine clinical care. AS events from RNA sequencing data were identified and further characterized as (1) alternative splice 3’ site (A3), (2) alternative splice 5’ site (A5), (3) exon skipping (ES), (4) intron retention (IR), and (5) mutually exclusive exons splice events (MUT). The Bisbee outlier analysis was performed against normal kidney tissues from the GTEx tissue library to further identify tumor-associated splice events. Outlier splice events were categorized as either non-coding/protein loss/silent, isoform switch, novel, or unknown. Results: Overall, 147 RCC pts (77% male) with RNA sequencing data were included in this analysis. Median age at diagnosis was 60 (range 31-94) and 97% of pts had metastatic RCC. The distribution of histology was 85% clear cell RCC followed by 11% papillary RCC. The AS analysis identified 25,928 outlier splice events. Approximately 60% of these were predicted to be protein-coding events, with the majority arising from IR and ES. These were followed by A3, A5, and MUT, in descending order of frequency. We also examined tumor-associated novel outlier events where 70% of analyzed RCC tumor samples noted 34 tumor-associated novel events were present, shared in most of the cohort and found an enrichment for IR events leading to frame disruptions. Data of splice variants will be presented at the meeting. Conclusions: In depth examination of this large cohort suggests that IR resulting from AS events occur frequently within RCC. Further efforts to investigate the association of AS events and clinical outcomes are underway.

Association of intra-tumoral microbiome and response to immune checkpoint inhibitors (ICIs) in patients with metastatic renal cell carcinoma (mRCC)

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Background: Multiple studies have suggested that the gut microbiome plays a modulatory role in ICI activity and that specific bacteria and/or cumulative microbial diversity may drive response in patients (pts) with mRCC (Routy et al Science 2018; Salgia et al Eur Urol 2020). Even though the tumor microenvironment has substantial bacterial proliferation (Heymann et al Cancer L. 2021), there is a paucity of data assessing the impact of intra-tumoral microbiota in response to ICI therapy. In this study, we sought to explore this association in pts with mRCC. Methods: Pts diagnosed with mRCC who had available RNA sequencing (RNA-seq) data collected in the course of routine clinical care and who were treated with ICIs were retrospectively identified.Intra-tumoral microbiome analysis was performed on formalin-fixed paraffin-embedded samples. Following quality and adapter trimming, RNA-seq reads were mapped to a human genome to filter host reads using the Burrows-Wheeler alignment (BWA) tool. Taxonomic classification was performed using Kraken2 and the absolute abundances of species were estimated using Bracken. The relative abundances among all non-human species were calculated. Statistical testing with Student’s t-test was performed to compare the relative abundance for all species seen within pts who responded to ICIs and those who did not. Results: Among the 28 pts (22:6, M:F) included in this analysis, 24 (86%) had clear cell histology and 20 (71%) were IMDC intermediate/poor risk. All of the samples were collected prior to starting treatment with ICIs and the majority of these (57%) were collected from the primary site. 11 pts (39%) received ICIs as first line treatment and 17 (61%) as second line. Clinical response was seen in 50% of pts included in the study and the most common rendered treatment was nivolumab (17 pts). In the overall cohort, Cutibacterium acne, Moraxella osloensis, and Pasteurella multocida had the highest relative abundances. Additionally, significant differences in relative abundances of specific bacteria were found between ICI responders and non-responders. Among these, Stenotrophomonas maltophilia (p = 0.037) and Corynebacterium sp. zg-917 (p = 0.035) had significantly higher relative abundances in pts who responded to ICIs. Conclusions: This is the first study evaluating the association between intra-tumoral microbiome and response to ICIs in pts with mRCC. Among bacteria associated with response, several have particular relevance – for instance, Corynebacterium spp. have been studied for decades as a possible adjunct to immunotherapeutic agents such as BCG. Efforts are ongoing to validate these findings in a larger cohort.

Prolonging utilization of systemic therapy in oligoprogressive metastatic renal cell carcinoma using stereotactic body radiation therapy

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Background: SBRT in indicated for the management of locally recurrent and oligometastatic mRCC as per National Comprehensive Cancer Network guidelines. Our study evaluates both the efficacy of radiotherapy (RT) in prolonging systemic treatment along with RT toxicity in the oligoprogressive RCC setting. Methods: A single institution retrospective data collection was performed in which we identified mRCC patients who experienced oligoprogression (defined as <1 sites of progressive disease) while on an FDA approved systemic therapy and were concurrently treated with SBRT, while remaining on the same therapy. Clinicopathologic characteristics and SBRT-related data along with duration of systemic therapy (DOT) were collected. DOT was then quantified into two categories which included the duration of systemic therapy prior to oligoprogression (DOT[P]) and duration of systemic therapy after completion of SBRT (DOT[S]). The ratio of DOT[S]/DOT[P] was calculated to determine the impact of SBRT on systemic treatment prolongation. Results: 23 patients diagnosed with mRCC meeting criteria were identified, 91% (n = 21) with clear cell histology and 9% (n = 2) with papillary histology. At the time of oligoprogression, 15 patients (65%) were on immunotherapy, 7 patients (30%) were on targeted therapy, and 1 patient (5%) was on combination therapy. We noted the preponderance of patients were on a first-line therapy at the time of oligoprogression (n = 10, 43%). A median of 2 (range, 1-3) lesions were treated per patient, with lung being the most frequent site (n = 14, 40%). The median total dose of SBRT was 30 Gy (range, 27-50 Gy) with a median dose per fraction of 6 Gy (range, 3-12 Gy). SBRT related toxicities, all of which were grade <2, were noted in 5 patients (22%), of which fatigue was the most frequent side effect (n = 3, 13%). Median DOT[S] was 13.4 months (range, 0.5-37.7 months) and the median DOT[P] was 12.8 months (range, 0.4-46.3 months). Results demonstrated a median DOT[S]/DOT[P] ratio to be 1.3 (range, 0.01-25.8). Conclusions: Based on our data, we discovered the addition of SBRT to systemic therapy during oligoprogression is not only well-tolerated, but that this treatment had clinical benefit in prolonging time on systemic therapy for patients with mRCC. The utilization of SBRT may prolong lines of therapy, thereby decreasing additional toxicities associated with exposure to new regimens.

Interactions of SARS-CoV-2 envelope protein with amilorides correlate with antiviral activity

SARS-CoV-2 is the novel coronavirus that is the causative agent of COVID-19, a sometimes-lethal respiratory infection responsible for a world-wide pandemic. The envelope (E) protein, one of four structural proteins encoded in the viral genome, is a 75-residue integral membrane protein whose transmembrane domain exhibits ion channel activity and whose cytoplasmic domain participates in protein-protein interactions. These activities contribute to several aspects of the viral replication-cycle, including virion assembly, budding, release, and pathogenesis. Here, we describe the structure and dynamics of full-length SARS-CoV-2 E protein in hexadecylphosphocholine micelles by NMR spectroscopy. We also characterized its interactions with four putative ion channel inhibitors. The chemical shift index and dipolar wave plots establish that E protein consists of a long transmembrane helix (residues 8–43) and a short cytoplasmic helix (residues 53–60) connected by a complex linker that exhibits some internal mobility. The conformations of the N-terminal transmembrane domain and the C-terminal cytoplasmic domain are unaffected by truncation from the intact protein. The chemical shift perturbations of E protein spectra induced by the addition of the inhibitors demonstrate that the N-terminal region (residues 6–18) is the principal binding site. The binding affinity of the inhibitors to E protein in micelles correlates with their antiviral potency in Vero E6 cells: HMA ≈ EIPA > DMA >> Amiloride, suggesting that bulky hydrophobic groups in the 5’ position of the amiloride pyrazine ring play essential roles in binding to E protein and in antiviral activity. An N15A mutation increased the production of virus-like particles, induced significant chemical shift changes from residues in the inhibitor binding site, and abolished HMA binding, suggesting that Asn15 plays a key role in maintaining the protein conformation near the binding site. These studies provide the foundation for complete structure determination of E protein and for structure-based drug discovery targeting this protein.

The novel coronavirus SARS-CoV-2, the causative agent of the world-wide pandemic of COVID-19, has become one of the greatest threats to human health. While rapid progress has been made in the development of vaccines, drug discovery has lagged, partly due to the lack of atomic-resolution structures of the free and drug-bound forms of the viral proteins. The SARS-CoV-2 envelope (E) protein, with its multiple activities that contribute to viral replication, is widely regarded as a potential target for COVID-19 treatment. As structural information is essential for drug discovery, we established an efficient sample preparation system for biochemical and structural studies of intact full-length SARS-CoV-2 E protein and characterized its structure and dynamics. We also characterized the interactions of amilorides with specific E protein residues and correlated this with their antiviral activity during viral replication. The binding affinity of the amilorides to E protein correlated with their antiviral potency, suggesting that E protein is indeed the likely target of their antiviral activity. We found that residue asparagine15 plays an important role in maintaining the conformation of the amiloride binding site, providing molecular guidance for the design of inhibitors targeting E protein.