Restaging With Prostate-Specific Membrane Antigen Imaging in Metastatic Castration-Resistant Prostate Cancer: When Seeing More Is Detrimental to Care

#PSMA is amazing new tech but is using it to expedite the call of disease progression helping #ProstateCancer patients?

Tumor cell-based liquid biopsy using high-throughput microfluidic enrichment of entire leukapheresis product

Circulating Tumor Cells (CTCs), interrogated by sampling blood from patients with cancer, contain multiple analytes, including intact RNA, high molecular weight DNA, proteins, and metabolic markers. However, the clinical utility of tumor cell-based liquid biopsy has been limited since CTCs are very rare, and current technologies cannot process the blood volumes required to isolate a sufficient number of tumor cells for in-depth assays. We previously described a high-throughput microfluidic prototype utilizing high-flow channels and amplification of cell sorting forces through magnetic lenses. Here, we apply this technology to analyze patient-derived leukapheresis products, interrogating a mean blood volume of 5.83 liters from patients with metastatic cancer, with a median of 2,799 CTCs purified per patient. Isolation of many CTCs from individual patients enables characterization of their morphological and molecular heterogeneity, including cell and nuclear size and RNA expression. It also allows robust detection of gene copy number variation, a definitive cancer marker with potential diagnostic applications. High-volume microfluidic enrichment of CTCs constitutes a new dimension in liquid biopsies.

Clinical Outcomes of De Novo Versus Relapsed Early Metastatic Testicular Seminoma Treated With Contemporary Radiation Therapy

PURPOSE

Chemotherapy (CHT) or radiation therapy (RT) are first-line treatments for clinical stage II (CS-II) testicular seminoma. Historically, clinical stage I (CS-I) seminoma was also treated with CHT or RT, but in the past 2 decades practice has shifted toward active surveillance for CS-I with RT or CHT reserved for patients with progression to CS-II. Limited data exist on contemporary RT techniques and patient stratification (ie, de novo [CS-II at orchiectomy] vs relapsed [CS-II diagnosed during surveillance after orchiectomy for CS-I]). We investigated outcomes in CS-II patients treated with RT in the modern era across 2 institutions.

METHODS AND MATERIALS

A retrospective review identified 73 patients treated with RT for CS-II A or B seminoma between 2001 and 2022. Recurrence-free survival (RFS) was calculated by the Kaplan-Meier method and univariate analyses were performed with log-rank or Cox proportional hazard regression. Recurrence was defined as biopsy-proven metastatic seminoma after RT completion. Second malignancies were defined as a biopsy-proven malignancy originating in the prior RT field.

RESULTS

Thirty-eight (52%) patients presented with de novo CS-II and 35 (48%) patients had relapsed CS-II. Median follow-up was 4.8 years (IQR: 2.3-8.1). Five-year RFS was 82% overall (92% in relapsed patients and 73% in de novo patients). Relapsed CS-II disease had lower recurrence rates after RT compared with de novo CS-II disease. All recurrences occurred outside the prior RT field and were salvaged. Disease-specific survival was 100%. Two second malignancies occurred (prostate, colorectal cancer at 67 months and 119 months post-RT, respectively).

CONCLUSIONS

In patients with CS-II seminoma treated with modern RT, there were no in-field recurrences. Presentation with de novo CS-II is associated with out-of-field recurrence. Subject to further larger-scale validation, our results suggest that compared with CS-II at time of relapse, de novo CS-II may portend more aggressive or micrometastatic disease beyond the retroperitoneum, raising the possibility of benefit from CHT after radiation.

The radiopharmaceutical radium-223 has immunomodulatory effects in patients and facilitates anti-programmed death receptor-1 therapy in murine models of bone metastatic prostate cancer

BACKGROUND & PURPOSE

Radium-223 (Ra223) improves survival in metastatic prostate cancer (mPC), but its impact on systemic immunity is unclear, and biomarkers of response are lacking. We examined markers of immunomodulatory activity during standard clinical Ra223 and studied the impact of Ra223 on response to immune checkpoint inhibition (ICI) in preclinical models.

MATERIALS & METHODS

We conducted a single-arm biomarker study of Ra223 in 22 bone mPC patients. We measured circulating immune cell subsets and a panel of cytokines before and during Ra223 therapy and correlated them with overall survival (OS). Using two murine mPC models-orthotopic PtenSmad4-null and TRAMP-C1 grafts in syngeneic immunocompetent mice-we tested the efficacy of combining Ra223 with ICI.

RESULTS

Above-median level of IL-6 at baseline was associated with a median OS of 358 versus 947 days for below levels; p = 0.044, from the log-rank test. Baseline PlGF and PSA inversely correlated with OS (p = 0.018 and p = 0.037, respectively, from the Cox model). Ra223 treatment was associated with a mild decrease in some peripheral immune cell populations and a shift in the proportion of MDSCs from granulocytic to myeloid. In mice, Ra223 increased the proliferation of CD8+ and CD4+ helper T cells without leading to CD8+ T cell exhaustion in the mPC lesions. In one of the models, combining Ra223 and anti-PD-1 antibody significantly prolonged survival, which correlated with increased CD8+ T cell infiltration in tumor tissue.

CONCLUSION

The inflammatory cytokine IL-6 and the angiogenic biomarker PlGF at baseline were promising outcome biomarkers after standard Ra223 treatment. In mouse models, Ra223 increased intratumoral CD8+ T cell infiltration and proliferation and could improve OS when combined with anti-PD-1 ICI.

Circulating and Imaging Biomarkers of Radium-223 Response in Metastatic Castration-Resistant Prostate Cancer

PURPOSE

Radium-223 improves overall survival (OS) and reduces skeletal events in patients with bone metastatic castration-resistant prostate cancer (CRPC), but relevant biomarkers are lacking. We evaluated automated bone scan index (aBSI) and circulating tumor cell (CTC) analyses as potential biomarkers of prognosis and activity.

PATIENTS AND METHODS

Patients with bone metastatic CRPC were enrolled on a prospective single-arm study of standard radium-223. 99mTc-MDP bone scan images at baseline, 2 months, and 6 months were quantitated using aBSI. CTCs at baseline, 1 month, and 2 months were enumerated and assessed for RNA expression of prostate cancer-specific genes using microfluidic enrichment followed by droplet digital polymerase chain reaction.

RESULTS

The median OS was 21.3 months in 22 patients. Lower baseline aBSI and minimal change in aBSI (<+0.7) from baseline to 2 months were each associated with better OS (P = .00341 and P = .0139, respectively). The higher baseline CTC count of ≥5 CTC/7.5 mL was associated with worse OS (median, 10.1 v 32.9 months; P = .00568). CTCs declined at 2 months in four of 15 patients with detectable baseline CTCs. Among individual genes in CTCs, baseline expression of the splice variant AR-V7 was significantly associated with worse OS (hazard ratio, 5.20 [95% CI, 1.657 to 16.31]; P = .00195). Baseline detectable AR-V7, higher aBSI, and CTC count ≥5 CTC/7.5 mL continued to have a significant independent negative impact on OS after controlling for prostate-specific antigen or alkaline phosphatase.

CONCLUSION

Quantitative bone scan assessment with aBSI and CTC analyses are prognostic markers in patients treated with radium-223. AR-V7 expression in CTCs is a particularly promising prognostic biomarker and warrants validation in larger cohorts.

Genomic Tumor Correlates of Clinical Outcomes Following Organ-Sparing Chemoradiation Therapy for Bladder Cancer

PURPOSE

There is an urgent need for biomarkers of radiation response in organ-sparing therapies. Bladder preservation with trimodality therapy (TMT), consisting of transurethral tumor resection followed by chemoradiation, is an alternative to radical cystectomy for muscle-invasive bladder cancer (MIBC), but molecular determinants of response are poorly understood.

EXPERIMENTAL DESIGN

We characterized genomic and transcriptomic features correlated with long-term response in a single institution cohort of patients with MIBC homogeneously treated with TMT. Pretreatment tumors from 76 patients with MIBC underwent whole-exome sequencing; 67 underwent matched transcriptomic profiling. Molecular features were correlated with clinical outcomes including modified bladder-intact event-free survival (mBI-EFS), a composite endpoint that reflects long-term cancer control with bladder preservation.

RESULTS

With a median follow-up of 74.6 months in alive patients, 37 patients had favorable long-term response to TMT while 39 had unfavorable long-term response. Tumor mutational burden was not associated with outcomes after TMT. DNA damage response gene alterations were associated with improved locoregional control and mBI-EFS. Of these alterations, somatic ERCC2 mutations stood out as significantly associated with favorable long-term outcomes; patients with ERCC2 mutations had significantly improved mBI-EFS [HR, 0.15; 95% confidence interval (CI), 0.06-0.37; P = 0.030] and improved BI-EFS, an endpoint that includes all-cause mortality (HR, 0.33; 95% CI, 0.15-0.68; P = 0.044). ERCC2 mutant bladder cancer cell lines were significantly more sensitive to concurrent cisplatin and radiation treatment in vitro than isogenic ERCC2 wild-type cells.

CONCLUSIONS

Our data identify ERCC2 mutation as a candidate biomarker associated with sensitivity and long-term response to chemoradiation in MIBC. These findings warrant validation in independent cohorts.

Impact of Testosterone Recovery on Clinical Outcomes of Patients Treated with Salvage Radiotherapy and Androgen Suppression: A Secondary Analysis of the NRG/RTOG 0534 Sport Phase 3 Trial

PURPOSE/OBJECTIVE(S)

Testosterone (T) kinetics and its relationship with clinical outcomes has not been studied in trials using salvage radiotherapy and androgen deprivation therapy (ADT). We performed a secondary analysis of the NRG Oncology/RTOG 0534 SPPORT trial, which compared prostate bed radiotherapy (PBRT) (arm 1), PBRT + short-term androgen deprivation therapy (ADT) (arm 2), or PBRT + pelvic lymph node radiotherapy (PLNRT) + short-term ADT (arm 3). We assessed longitudinal serum T levels and the impact of testosterone recovery (TR) on clinical outcomes.

MATERIALS/METHODS

ADT was given for 4-6 months in arms 2 and 3, starting 2 months prior to radiotherapy. The trial excluded patients with baseline T < 40% of the lower limit of normal. TR was defined in 3 ways: 1) return to non-castrate level (>50 ng/dL), 2) return to normal level (>300 ng/dL), and 3) return to baseline level. Time to TR was estimated using cumulative incidence and death without an event considered a competing risk. Unadjusted and adjusted hazard ratios and 95% confidence intervals (CIs) were calculated using Cox proportional hazards model. Freedom from progression (FFP) was defined as biochemical failure according to the Phoenix definition (PSA ≥2 ng/mL over the nadir PSA), clinical failure (local, regional, or distant), or death from any cause.

RESULTS

A total of 1699 patients with T at baseline and at least 1 follow-up assessment were included. The median age was 64 years (IQR 59 - 69), 12.8% were black, 14.9% had diabetes, and 54.1% were former or current smokers. Median baseline T in arms 1, 2 and 3 was 320 ng/dL (IQR 239 - 424), 319 ng/dL (IQR 237 - 438) and 330 ng/dL (IQR 252 - 446), respectively. At 6 months, median T in arms 1, 2 and 3 was 290 ng/dL (IQR 210 - 390), 190.4 ng/dL (IQR 66 - 296) and 191 ng/dL (IQR 40.5 - 313). At 2 years, in arms 2 and 3, TR to non-castrate, normal and baseline levels were 95%, 55% and 23%, respectively. At 5 years, in arms 2 and 3, TR to non-castrate, normal and baseline levels were 98%, 73% and 42%, respectively. FFP was superior in arms 2 and 3 vs. arm 1 in patients with TR by all three definitions. In patients with recovered T to normal levels by 2 years (n = 904), the 5-year FFP rates were 71.8% (95% CI 66.9-76.6) in arm 1, 77.2% (72.1-82.2) in arm 2, and 86.3% (82.3-90.3) in arm 3 (arm 2 vs arm 1: HR 0.74, 95% CI 0.56-0.98, p = 0.034; arm 3 vs arm 1: HR 0.54, 95% CI 0.40-0.72, p<.0001).

CONCLUSION

This work represents the largest study of T kinetics in patients treated with salvage radiation and ADT. Approximately half of patients did not normalize their T levels by 2 years. Our data validate an incremental and meaningful FFP benefit of adding short-term ADT and PLNRT to PBRT independent of T recovery.

Prognostic Significance of Pretreatment Immune Cell Infiltration in Muscle Invasive Bladder Cancer Treated with Definitive Chemoradiation: Analysis of NRG RTOG 0524 and 0712

PURPOSE/OBJECTIVE(S)

Chemoradiation therapy (CRT) is an organ conserving approach in the treatment of locally advanced bladder cancer. Chemoradiation is thought to potentially result in immunogenic stimulation, and bladder cancer is often a tumor with high immune cell infiltration. Thus, we aimed to profile the tumor immune microenvironment of bladder cancer and identify prognostic immune biomarkers for CRT response by profiling tumor samples from NRG/RTOG 0524 and 0712, two prospective trials of CRT in muscle invasive bladder cancer (MIBC).

MATERIALS/METHODS

Pretreatment tissue samples from both trials were profiled using Cofactor Genomics ImmunoPrism, an RNA sequencing assay that uses gene expression profiles to quantify immune cell populations in the tumor microenvironment (TME). Differential gene expression was estimated for different immune cell type proportions across samples. Kaplan-Meier survival analysis and log rank tests were performed to evaluate differences in overall survival (OS) stratified by genes influenced by immune cell proportions or genes associated with immune response signatures.

RESULTS

A total of 70 samples (43 from RTOG 0524 and 27 from RTOG 0712) underwent analysis using the ImmunoPrism assay. Immune cell proportions were as follows: CD8 T cells: median 1.2%, CD4 T cells: median 0.8%, Treg cells: median 9.2%, CD19 B cells: median 5.1%, M2 macrophages: median 0.8%, M1 macrophages: median 0%. Unbiased clustering based on gene expression profiles driven by immune cell proportions demonstrated two groups: cluster 1 with a low percentage of immune cells and shorter OS (median 31 months) and cluster 2 with a high percentage of immune cells and longer OS (median 101 months, p = 0.036). Higher expression of genes associated with T cell infiltration (CD8A and ICOS) was associated with improved OS (104 vs 35 months, p = 0.028, HR = 0.48 (0.25 - 0.94), p = 0.031) as was higher expression of IDO1, which is associated with the interferon gamma pathway (104 vs 35 months, p = 0.042, HR = 0.49 (0.24 - 0.99), p = 0.046).

CONCLUSION

Bladder tumors have a wide range of immune cell infiltration in the TME. Increased immune cell proportions are prognostic for OS following CRT, as well as a higher expression of genes associated with T cell infiltration interferon gamma signaling. These findings have implications for the integration of immunotherapy in the definitive management of MIBC; and can be explored further in the ongoing NRG/SWOG 1806 trial.

Quality of Life Results of Addition of Androgen Deprivation Therapy and Pelvic Lymph Node Treatment to Prostate Bed Salvage Radiotherapy: NRG Oncology/RTOG 0534 SPPORT

PURPOSE/OBJECTIVE(S)

Report the quality of life (QOL) analysis of the SPPORT trial of men with a detectable prostate specific antigen (PSA) after prostatectomy for prostate cancer randomized to (Arm 1) salvage prostate bed radiotherapy (PBRT), (Arm 2) 4-6 months of short-term androgen deprivation therapy (STADT) + PBRT, and (Arm 3) pelvic lymph node radiotherapy (PLNRT) + STADT + PBRT. Primary analysis established a benefit of adding PLNRT and STADT to PBRT. There was higher short term but no statistically significant difference in long term adverse events with the exception of blood or bone marrow events.

MATERIALS/METHODS

QOL endpoints were assessed at baseline, 6 weeks after RT start, 1 and 5 years, including Expanded Prostate Cancer Index Composite (EPIC) (bowel, urinary, sexual, and hormonal domains), Hopkins Symptom Checklist (HSCL-25) (depressive symptoms), and the EuroQol (EQ-5D) (health state weights used in quality adjusted life years (QALYs). In addition to statistical significance, differences in scores were assessed using 0.5 standard deviation (SD) as the criterion for clinical importance. Difference among arms was assessed using pairwise t-tests, Fisher's exact test, and mixed effects regression modeling. To control for multiplicity, the p-value required for statistical significance is p<0.025.

RESULTS

Six hundred forty-four patients consented to QOL, about 210 on each arm. Baseline characteristics were not significantly different among arms: 81% were white and 54% <65 years. For EPIC, bowel domain scores decreased at 6 weeks post-RT then increased by years 1 and 5, although not to baseline levels. One clinically significant difference in bowel scores was Arm 3 vs. Arm 1 at 6 weeks. For the urinary domain, scores decreased at 6 weeks post-RT and remained below baseline at 1 and 5 years, but there were no significant differences among arms. For the sexual domain, there were statistically significant differences between arms at 6 weeks and 1 year with patients receiving STADT exhibiting poorer sexual QOL scores. By year 5 the differences were no longer significant. A similar pattern was seen for the hormonal domain. For HSCL-25, differences at 6 weeks were statistically but not clinically significant, and there were no significant differences at the later time points. Comparisons of QALYs for overall survival over an 8-year horizon showed no significant group differences, with a mean of about 7.8 in each arm. Regarding freedom from progression, QALY means were 5.7, 6.5, and 7.4 years for Arms 1, 2, and 3, respectively, with a significant difference between Arms 3 and 1 (p = <.001) favoring the more intensive treatment.

CONCLUSION

While QOL generally declined among all arms at 6 weeks post RT, there were no clinically significant differences in QOL among arms at 5 years. QALYs for freedom from progression favored STADT + PLNRT + PBRT for salvage treatment of prostate cancer.

Impact of a negative confirmatory biopsy on risk of disease progression among men on active surveillance for prostate cancer

OBJECTIVE

Most prostate cancer active surveillance (AS) protocols suggest a confirmatory biopsy within 12 to 18 months of diagnosis to mitigate the risk of unsampled high-grade disease. We investigate whether the results of confirmatory biopsy impact AS outcomes and could be used to tailor surveillance intensity.

METHODS

We retrospectively reviewed our institutional database of prostate cancer patients managed by AS from 1997 to 2019 who underwent confirmatory biopsy and ≥3 biopsies overall. Biopsy progression was defined as either an increase in grade group or an increase in the proportion of positive biopsy cores to >34% and was compared between patients with a negative vs positive confirmatory biopsy using the Kaplan-Meier method and Cox proportional hazards regression.

RESULTS

We identified 452 patients meeting inclusion criteria for this analysis, of whom 169 (37%) had a negative confirmatory biopsy. With a median follow-up of 6.8 years, 37% of patients progressed to treatment, most commonly due to biopsy progression. A negative confirmatory biopsy was significantly associated with biopsy progression-free survival in multivariable analysis (HR 0.54, 95% CI 0.34-0.88, P = 0.013), adjusting for known clinical and pathologic factors, including use of mpMRI prior to confirmatory biopsy. Negative confirmatory biopsy was also associated with an increased risk of adverse pathologic features at prostatectomy but not with biochemical recurrence among men who ultimately underwent definitive treatment.

CONCLUSIONS

A negative confirmatory biopsy is associated with a lower risk of biopsy progression. While the increased risk of adverse pathology at time of definitive treatment sounds a small cautionary note regarding decreasing surveillance intensity, the majority of such patients have a favorable outcome on AS.

DNA hypomethylation silences anti-tumor immune genes in early prostate cancer and CTCs

Cancer is characterized by hypomethylation-associated silencing of large chromatin domains, whose contribution to tumorigenesis is uncertain. Through high-resolution genome-wide single-cell DNA methylation sequencing, we identify 40 core domains that are uniformly hypomethylated from the earliest detectable stages of prostate malignancy through metastatic circulating tumor cells (CTCs). Nested among these repressive domains are smaller loci with preserved methylation that escape silencing and are enriched for cell proliferation genes. Transcriptionally silenced genes within the core hypomethylated domains are enriched for immune-related genes; prominent among these is a single gene cluster harboring all five CD1 genes that present lipid antigens to NKT cells and four IFI16-related interferon-inducible genes implicated in innate immunity. The re-expression of CD1 or IFI16 murine orthologs in immuno-competent mice abrogates tumorigenesis, accompanied by the activation of anti-tumor immunity. Thus, early epigenetic changes may shape tumorigenesis, targeting co-located genes within defined chromosomal loci. Hypomethylation domains are detectable in blood specimens enriched for CTCs.

Radical cystectomy versus trimodality therapy for muscle-invasive bladder cancer: a multi-institutional propensity score matched and weighted analysis

BACKGROUND

Previous randomised controlled trials comparing bladder preservation with radical cystectomy for muscle-invasive bladder cancer closed due to insufficient accrual. Given that no further trials are foreseen, we aimed to use propensity scores to compare trimodality therapy (maximal transurethral resection of bladder tumour followed by concurrent chemoradiation) with radical cystectomy.

METHODS

This retrospective analysis included 722 patients with clinical stage T2-T4N0M0 muscle-invasive urothelial carcinoma of the bladder (440 underwent radical cystectomy, 282 received trimodality therapy) who would have been eligible for both approaches, treated at three university centres in the USA and Canada between Jan 1, 2005, and Dec 31, 2017. All patients had solitary tumours less than 7 cm, no or unilateral hydronephrosis, and no extensive or multifocal carcinoma in situ. The 440 cases of radical cystectomy represent 29% of all radical cystectomies performed during the study period at the contributing institutions. The primary endpoint was metastasis-free survival. Secondary endpoints included overall survival, cancer-specific survival, and disease-free survival. Differences in survival outcomes by treatment were analysed using propensity scores incorporated in propensity score matching (PSM) using logistic regression and 3:1 matching with replacement and inverse probability treatment weighting (IPTW).

FINDINGS

In the PSM analysis, the 3:1 matched cohort comprised 1119 patients (837 radical cystectomy, 282 trimodality therapy). After matching, age (71·4 years [IQR 66·0-77·1] for radical cystectomy vs 71·6 years [64·0-78·9] for trimodality therapy), sex (213 [25%] vs 68 [24%] female; 624 [75%] vs 214 [76%] male), cT2 stage (755 [90%] vs 255 [90%]), presence of hydronephrosis (97 [12%] vs 27 [10%]), and receipt of neoadjuvant or adjuvant chemotherapy (492 [59%] vs 159 [56%]) were similar between groups. Median follow-up was 4·38 years (IQR 1·6-6·7) versus 4·88 years (2·8-7·7), respectively. 5-year metastasis-free survival was 74% (95% CI 70-78) for radical cystectomy and 75% (70-80) for trimodality therapy with IPTW and 74% (70-77) and 74% (68-79) with PSM. There was no difference in metastasis-free survival either with IPTW (subdistribution hazard ratio [SHR] 0·89 [95% CI 0·67-1·20]; p=0·40) or PSM (SHR 0·93 [0·71-1·24]; p=0·64). 5-year cancer-specific survival for radical cystectomy versus trimodality therapy was 81% (95% CI 77-85) versus 84% (79-89) with IPTW and 83% (80-86) versus 85% (80-89) with PSM. 5-year disease-free survival was 73% (95% CI 69-77) versus 74% (69-79) with IPTW and 76% (72-80) versus 76% (71-81) with PSM. There were no differences in cancer-specific survival (IPTW: SHR 0·72 [95% CI 0·50-1·04]; p=0·071; PSM: SHR 0·73 [0·52-1·02]; p=0·057) and disease-free survival (IPTW: SHR 0·87 [0·65-1·16]; p=0·35; PSM: SHR 0·88 [0·67-1·16]; p=0·37) between radical cystectomy and trimodality therapy. Overall survival favoured trimodality therapy (IPTW: 66% [95% CI 61-71] vs 73% [68-78]; hazard ratio [HR] 0·70 [95% CI 0·53-0·92]; p=0·010; PSM: 72% [69-75] vs 77% [72-81]; HR 0·75 [0·58-0·97]; p=0·0078). Outcomes for radical cystectomy and trimodality therapy were not statistically different among centres for cancer-specific survival and metastasis-free survival (p=0·22-0·90). Salvage cystectomy was done in 38 (13%) trimodality therapy patients. Pathological stage in the 440 radical cystectomy patients was pT2 in 124 (28%), pT3-4 in 194 (44%), and 114 (26%) node positive. The median number of nodes removed was 39, the soft tissue positive margin rate was 1% (n=5), and the perioperative mortality rate was 2·5% (n=11).

INTERPRETATION

This multi-institutional study provides the best evidence to date showing similar oncological outcomes between radical cystectomy and trimodality therapy for select patients with muscle-invasive bladder cancer. These results support that trimodality therapy, in the setting of multidisciplinary shared decision making, should be offered to all suitable candidates with muscle-invasive bladder cancer and not only to patients with significant comorbidities for whom surgery is not an option.

FUNDING

Sinai Health Foundation, Princess Margaret Cancer Foundation, Massachusetts General Hospital.

Efficacy and Safety of Telaglenastat Plus Cabozantinib vs Placebo Plus Cabozantinib in Patients With Advanced Renal Cell Carcinoma: The CANTATA Randomized Clinical Trial

Importance

Dysregulated metabolism is a hallmark of renal cell carcinoma (RCC). Glutaminase is a key enzyme that fuels tumor growth by converting glutamine to glutamate. Telaglenastat is an investigational, first-in-class, selective, oral glutaminase inhibitor that blocks glutamine utilization and downstream pathways. Preclinically, telaglenastat synergized with cabozantinib, a VEGFR2/MET/AXL inhibitor, in RCC models.

Objective

To compare the efficacy and safety of telaglenastat plus cabozantinib (Tela + Cabo) vs placebo plus cabozantinib (Pbo + Cabo).

Design, Setting, and Participants

CANTATA was a randomized, placebo-controlled, double-blind, pivotal trial conducted at sites in the US, Europe, Australia, and New Zealand. Eligible patients had metastatic clear-cell RCC following progression on 1 to 2 prior lines of therapy, including 1 or more antiangiogenic therapies or nivolumab plus ipilimumab. The data cutoff date was August 31, 2020. Data analysis was performed from December 2020 to February 2021.

Interventions

Patients were randomized 1:1 to receive oral cabozantinib (60 mg daily) with either telaglenastat (800 mg twice daily) or placebo until disease progression or unacceptable toxicity.

Main Outcomes and Measures

The primary end point was progression-free survival (Response Evaluation Criteria in Solid Tumors version 1.1) assessed by blinded independent radiology review.

Results

A total of 444 patients were randomized: 221 to Tela + Cabo (median [range] age, 61 [21-81] years; 47 [21%] women and 174 [79%] men) and 223 to Pbo + Cabo (median [range] age, 62 [29-83] years; 68 [30%] women and 155 [70%] men). A total of 276 (62%) patients had received prior immune checkpoint inhibitors, including 128 with prior nivolumab plus ipilimumab, 93 of whom had not received prior antiangiogenic therapy. Median progression-free survival was 9.2 months for Tela + Cabo vs 9.3 months for Pbo + Cabo (HR, 0.94; 95% CI, 0.74-1.21; P = .65). Overall response rates were 31% (69 of 221) with Tela + Cabo vs 28% (62 of 223) with Pbo + Cabo. Treatment-emergent adverse event (TEAE) rates were similar between arms. Grade 3 to 4 TEAEs occurred in 160 patients (71%) with Tela + Cabo and 172 patients (79%) with Pbo + Cabo and included hypertension (38 patients [17%] vs 40 patients [18%]) and diarrhea (34 patients [15%] vs 29 patients [13%]). Cabozantinib was discontinued due to AEs in 23 patients (10%) receiving Tela + Cabo and 33 patients (15%) receiving Pbo + Cabo.

Conclusions and Relevance

In this randomized clinical trial, telaglenastat did not improve the efficacy of cabozantinib in metastatic RCC. Tela + Cabo was well tolerated with AEs consistent with the known risks of both agents.

Trial Registration

ClinicalTrials.gov Identifier: NCT03428217.

Effective antiviral coatings for deactivating SARS-CoV-2 virus on N95 respirator masks or filters

The application of antiviral coatings to masks and respirators is a potential mitigating step toward reducing viral transmission during the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic. The use of appropriate masks, social distancing, and vaccines is the immediate solution for limiting the viral spread and protecting people from this virus. N95 respirator masks are effective in filtering the virus particles, but they cannot kill or deactivate the virus. We report a possible approach to deactivating SARS-CoV-2 by applying an antimicrobial coating (Goldshield 75) to masks and respirators, rendering them suitable for repeated use. Masks coated with Goldshield 75 demonstrated continuous inactivation of the Alpha and Beta variants of the SARS-CoV-2 over a 3-day period and no loss of inactivation when stored at temperatures at 50 °C.

Multicancer Early Detection Technologies: A Review Informed by Past Cancer Screening Studies

More than 75% of cancer-related deaths occur from cancers for which we do not screen. New screening liquid biopsies may help fill these clinical gaps, although evidence of benefit still needs to be assessed. Which lessons can we learn from previous efforts to guide those of the future? Screening trials for ovarian, prostate, pancreatic, and esophageal cancers are revisited to assess the evidence, which has been limited by small effect sizes, short duration of early-stage disease relative to screening frequency, study design, and confounding factors. Randomized controlled trials (RCT) to show mortality reduction have required millions of screening-years, two-decade durations, and been susceptible to external confounding. Future RCTs with late-stage incidence as a surrogate endpoint could substantially reduce these challenges, and clinical studies demonstrating safety and effectiveness of screening in high-risk populations may enable extrapolation to broader average-risk populations. Multicancer early detection tests provide an opportunity to advance these practical study designs. Conditional approvals based on RCTs with surrogate endpoints, contingent upon real world evidence generation and continuation of trials to definitive endpoints, may lower practical barriers to innovation in cancer screening and enable greater progress.

Charting a Path Towards Asian American Cancer Health Equity: A Way Forward

On July 29, 2021, the US Food and Drug Administration’s Oncology Center of Excellence convened Conversations on Cancer. This Conversation, the first ever by the US Food and Drug Administration, focused on Asian Americans and served as the platform for this Commentary. Panelists elaborated on topics ranging from heterogeneity in Asian American demographics to racism through a path to health equity and supplemented this Commentary with literature citations. Asian Americans are the fastest-growing US race group, yet data aggregation obscures distinctions and cancer disparities within the more than 24 million Asians living in the United States with harmful impacts on communities and patients, as illustrated by breast cancer survivor Susan Shinagawa’s patient-to-advocate journey. Bigotry against Asian Americans has been pervasive since the 19th century, but especially during the COVID-19 pandemic. Asian Americans are unique as the first US population to experience cancer as the leading cause of death. Asian Americans are disproportionately affected by cancers because of infectious origins and have the highest rates of lung cancer among never-smoking women. The infinitesimal proportion of the National Institutes of Health’s budget compared with experiencing the highest percentage increases of any US racial population more than 3 decades highlights the dearth of focused research among Asian Americans. Recognizing the heterogeneity of Asian Americans and that disaggregated data are critical for accurately characterizing distinct ethnic groups, focusing on the impact of racism and COVID-19 on cancer disparities, and focusing and prioritizing funding resources are necessary steps forward for achieving health equity for Asian Americans.

Telaglenastat Plus Cabozantinib or Everolimus for Advanced or Metastatic Renal Cell Carcinoma: An Open-Label Phase I Trial

PURPOSE

Dual inhibition of glucose and glutamine metabolism results in synergistic anticancer effects in solid tumor models. Telaglenastat, an investigational, small-molecule, glutaminase inhibitor, exhibits modest single-agent activity in renal cell carcinoma (RCC) patients. This phase Ib trial evaluated telaglenastat plus cabozantinib or everolimus, agents known to impair glucose metabolism in patients with metastatic RCC (mRCC).

PATIENTS AND METHODS

mRCC patients received escalating doses of telaglenastat [400-800 mg per os (p.o.) twice daily] in a 3 + 3 design, plus either everolimus (10 mg daily p.o.; TelaE) or cabozantinib (60 mg daily p.o.; TelaC). Tumor response (RECISTv1.1) was assessed every 8 weeks. Endpoints included safety (primary) and antitumor activity.

RESULTS

Twenty-seven patients received TelaE, 13 received TelaC, with median 2 and 3 prior therapies, respectively. Treatment-related adverse events were mostly grades 1 to 2, most common including decreased appetite, anemia, elevated transaminases, and diarrhea with TelaE, and diarrhea, decreased appetite, elevated transaminases, and fatigue with TelaC. One dose-limiting toxicity occurred per cohort: grade 3 pruritic rash with TelaE and thrombocytopenia with TelaC. No maximum tolerated dose (MTD) was reached for either combination, leading to a recommended phase II dose of 800-mg telaglenastat twice daily with standard doses of E or C. TelaE disease control rate (DCR; response rate + stable disease) was 95.2% [20/21, including 1 partial response (PR)] among 21 patients with clear cell histology and 66.7% (2/3) for papillary. TelaC DCR was 100% (12/12) for both histologies [5/10 PRs as best response (3 confirmed) in clear cell].

CONCLUSIONS

TelaE and TelaC showed encouraging clinical activity and tolerability in heavily pretreated mRCC patients.

Multi-institutional matched comparison of radical cystectomy to trimodality therapy for muscle-invasive bladder cancer

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Background: Prior randomized controlled trials (RCT) comparing bladder preservation to radical cystectomy (RC) for muscle invasive bladder cancer (MIBC) closed early due to lack of accrual. Given that no future RCTs are foreseen, and in the absence of level 1 data, we aimed to provide the best evidence possible on outcomes of matched cohorts comparing trimodality therapy (TMT, maximal transurethral resection of bladder tumor followed by concurrent chemoradiation) to RC in order to guide management. Methods: This retrospective analysis included 703 patients with MIBC clinical stage T2-T3/4aN0M0 MIBC urothelial carcinoma of the bladder, 421 RC and 282 TMT who would have been eligible for both TMT or RC, treated at the Massachusetts General Hospital, Boston; Princess Margaret Cancer Centre, Toronto; and University of Southern California, Los Angeles between 2005-2017. To compare homogeneous cohorts, all patients included in this analysis had solitary tumors < 7 cm, no or unilateral hydronephrosis, and no multifocal carcinoma in situ. Treatment propensity scores were estimated using logistic regression, and patients were matched 3:1 with replacement. Covariates included age, sex, clinical T stage, hydronephrosis, (neo)adjuvant chemotherapy, body mass index, smoking history, and ECOG status. Overall survival (OS) was estimated with adjusted Cox models; cancer-specific survival (CSS), distant failure-free survival, pelvic nodal failure-free survival and metastasis-free survival (combined distant and pelvic nodal failure) were estimated with adjusted competing risk models. Our primary endpoint of interest was metastasis-free survival. The analysis was performed as intent-to-treat. Results: The 3:1 matched cohort comprised of 1,116 patients (834 RC vs 282 TMT). After matching, age (71.3 vs 71.6), cT2 clinical stage (88 vs 90%), presence of hydronephrosis (12 vs 10%), and use of (neo)adjuvant chemotherapy (60 vs 65%) were similar between RC and TMT cohorts. Salvage cystectomy was performed in 38 patients (13%) treated by TMT. At 5 years, metastasis-free (73 vs 78%, p = 0.07), distant failure-free (78 vs 82%, p = 0.14), and pelvic nodal failure-free (96 vs 94%, p = 0.33) survival were not statistically different between RC and TMT, whereas CSS and OS favored TMT (78 vs 85%, p = 0.02; 70 vs 78%, p < 0.001). Outcomes for RC and TMT were not different among centers. Final pT stage in the RC patients was: pT0 14%, pT1 7%, pT2 29%, pT3/4 42% and N+ 24%. Peri RC mortality was 2.1% and median number of nodes removed was 40. NMIBC recurrence occurred in 57/278 (20.5%) TMT patients. Conclusions: This large multi-institutional contemporary study provides the best evidence to date, in the absence of randomized trials, supporting TMT for select patients with MIBC. Oncologic outcomes seem to be equivalent between TMT and RC, affirming the position that TMT should be offered as an effective alternative.

Phase 2 trial of CV301 vaccine plus atezolizumab (Atezo) in advanced urothelial carcinoma (aUC)

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Background: PD(L)1 inhibitors can achieve durable responses in aUC but only in a minority of patients (pts). Combination strategies with agents that “prime and stimulate” the immune system may improve outcomes. CV301 comprises 2 recombinant poxviruses, Modified Vaccinia Ankara (MVA) and Fowlpox (FPV), encoding the human transgenes for CEA, MUC-1, and a Triad of Co-stimulatory Molecules (TRICOM: ICAM-1, LFA-3, and B7-1). MVA-CV301 is used for priming and FPV-CV301 is used for booster doses. Preliminarily, BN-platform vaccine plus PD-(L)1 inhibitors exhibited synergistic preclinical anti-tumor efficacy and the combination of CV301 and anti-PD-(L)1 agent demonstrated an acceptable safety profile. We hypothesized that this combination would be safe and effective in cisplatin-ineligible or platinum-refractory pts with aUC. Methods: A Phase 2, single-arm multicenter trial was designed to study CV301 + atezo as 1st-line treatment in pts with aUC ineligible for cisplatin-based chemotherapy regardless of PD-L1 status (Cohort 1; C1) and in pts progressing on/after platinum-based chemotherapy (Cohort 2; C2). MVA-CV301 was given subcutaneously (SC) on Days 1 and 22 and FPV-CV301 SC from day 43 every 21 days for 4 doses, then every 6 weeks until 6 months, then every 12 weeks until 2 years. Atezo 1200mg IV was given every 21 days. Primary endpoint: objective response rate (ORR). Secondary endpoints: OS, PFS, response duration, AEs and antigen-specific T-cell responses to CEA and MUC-1 by ELISPOT. Using 1-sided α 2.5%/cohort, a 2-stage design with 14/19 and 13/22 stage 1/2 subjects, respectively, will achieve ≥70% power if the true ORR for C1 is 43% and C2 is 33%. 3 C1 and 2 C2 responders were required in stage 1 to move forward. Results: 43 evaluable pts were enrolled and received therapy: 19 in C1; 24 in C 2. Overall, 9 pts experienced ≥ Grade 3 AEs related to the combination of treatment: 5 in C1, and 4 in C2. In C1, 1 pt had partial response (PR), for ORR 5.3% (90%CI: 0.3, 22.6) and 5 (26.3%, 90%CI: 11.0, 47.6) had stable disease (SD) as best response. In C2, 1pt had CR and 1 had PR, for ORR 8.3% (90%CI: 1.5, 24.0) and 3 (12.5%, 90%CI: 3.5, 29.2) had SD as best response. Median PFS and OS in C1 were 2.0 mo and 13.8 mo, and in C2 1.95 and 8.13 mo, respectively. The trial was halted for futility. Responding pts in C2 exhibited T-cell responses to CEA and pts with SD exhibited responses to MUC-1. Conclusions: CV301 + atezo exhibited an acceptable safety profile but did not demonstrate sufficient efficacy in pts with aUC as 1st-line therapy in cisplatin-ineligible pts or in the platinum-refractory setting. The development of effective vaccines to generate robust and durable responses as single agents and/or combined with anti-PD(L)1 remains an unmet need in aUC. Clinical trial information: NCT03628716.

Outcomes of older men receiving docetaxel for metastatic hormone-sensitive prostate cancer

BACKGROUND

Most men who die of prostate cancer are older than 70 years. The ChemoHormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer (CHAARTED) randomized men of all ages with metastatic hormone-sensitive prostate cancer (mHSPC) to receive androgen deprivation therapy (ADT) with or without docetaxel demonstrating an overall survival (OS) benefit for docetaxel.

METHODS

In a post-hoc analysis of this trial, we assessed patient characteristics and OS in patients ≥70 years ("older men") versus <70 years ("younger men") with Cox proportional hazards models. In addition, we compared adverse events, therapy completion rate, and subsequent treatment patterns between these two groups using Chi-squared tests.

RESULTS

177 (22.4%) patients were ≥70 years. Docetaxel + ADT resulted in improved OS in both older and younger men (Hazard Ratio [HR] 0.45, 95%CI: 0.25-0.80 for older men; HR 0.71, 95%CI: 0.53-0.95 for younger men). This treatment benefit was seen for subgroups of older men with high volume disease (HR 0.43, 95%CI 0.23-0.79) and de novo metastatic disease (HR 0.36, 95%CI 0.19-0.69). A similar proportion of older and younger men completed six cycles of docetaxel (82.6% vs. 87.1%, p = 0.28). Rates of grade 3-5 adverse events were similar between older and younger men (36.8% vs. 26.8%, respectively, p = 0.069). The rate of any Grades 4-5 adverse events did not differ significantly between older and younger men (14.9% vs. 11.9%, respectively, p = 0.46). In the control arm, a smaller proportion of older men received subsequent cancer treatments (34.4% vs. 51.5%, p = 0.017) or subsequent docetaxel (25.6% vs. 37.6%, p = 0.035) compared to younger men.

CONCLUSIONS

Older men with mHSPC had similar OS benefit and clinical outcomes compared to younger men when receiving docetaxel + ADT. Oncologists should consider docetaxel chemotherapy as a favorable treatment option for older men with mHSPC who are fit for chemotherapy.

A method for the identification of COVID-19 biomarkers in human breath using Proton Transfer Reaction Time-of-Flight Mass Spectrometry

BACKGROUND

COVID-19 has caused a worldwide pandemic, making the early detection of the virus crucial. We present an approach for the determination of COVID-19 infection based on breath analysis.

METHODS

A high sensitivity mass spectrometer was combined with artificial intelligence and used to develop a method for the identification of COVID-19 in human breath within seconds. A set of 1137 positive and negative subjects from different age groups, collected in two periods from two hospitals in the USA, from 26 August, 2020 until 15 September, 2020 and from 11 September, 2020 until 11 November, 2020, was used for the method development. The subjects exhaled in a Tedlar bag, and the exhaled breath samples were subsequently analyzed using a Proton Transfer Reaction Time-of-Flight Mass Spectrometer (PTR-ToF-MS). The produced mass spectra were introduced to a series of machine learning models. 70% of the data was used for these sub-models' training and 30% was used for testing.

FINDINGS

A set of 340 samples, 95 positives and 245 negatives, was used for the testing. The combined models successfully predicted 77 out of the 95 samples as positives and 199 out of the 245 samples as negatives. The overall accuracy of the model was 81.2%. Since over 50% of the total positive samples belonged to the age group of over 55 years old, the performance of the model in this category was also separately evaluated on 339 subjects (170 negative and 169 positive). The model correctly identified 166 out of the 170 negatives and 164 out of the 169 positives. The model accuracy in this case was 97.3%.

INTERPRETATION

The results showed that this method for the identification of COVID-19 infection is a promising tool, which can give fast and accurate results.

CANTATA: Primary analysis of a global, randomized, placebo (Pbo)-controlled, double-blind trial of telaglenastat (CB-839) + cabozantinib versus Pbo + cabozantinib in advanced/metastatic renal cell carcinoma (mRCC) patients (pts) who progressed on immune checkpoint inhibitor (ICI) or anti-angiogenic therapies

4501

Background: Dysregulated metabolism is a hallmark of RCC, driven by overexpression of glutaminase (GLS), a key enzyme of glutamine metabolism. Telaglenastat (Tela) is an investigational, first-in-class, selective, oral GLS inhibitor that blocks glutamine utilization and critical downstream pathways. Preclinically, Tela synergized w/ cabozantinib (Cabo), a VEGFR2/MET/AXL inhibitor, against RCC tumors. In a Ph 1 study cohort, Tela+Cabo showed encouraging safety/efficacy as 2L+ therapy for mRCC. This trial compared Tela+Cabo vs Pbo+Cabo in previously treated pts w/ clear-cell mRCC (NCT03428217). Methods: Eligible pts had 1-2 prior lines of systemic therapy for mRCC, including ≥1 anti-angiogenic therapy or nivolumab + ipilimumab (nivo/ipi), KPS ≥70%, measurable disease (RECIST 1.1), no prior Cabo or other MET inhibitor. Pts were randomized 1:1 to receive Cabo (60 mg PO QD) with either Tela (800 mg PO BID) or Pbo, until disease progression/unacceptable toxicity, and were stratified by prior PD-(L)1 inhibitor therapy (Y/N) and IMDC prognostic risk group. Primary endpoint was progression-free survival (PFS; RECIST 1.1) by blinded independent radiology review. The study was designed to detect a PFS hazard ratio (HR) of 0.69 w/ alpha 0.05 and 85% power. Data cutoff date: August 31, 2020. Results: 444 pts were randomized (221 Tela+Cabo; 223 Pbo+Cabo). Baseline characteristics were balanced between arms. Median follow-up was 11.7 mo; 276 pts received prior ICI, including 128 w/ prior nivo/ipi. Median PFS (mPFS) was 9.2 mo for Tela+Cabo vs 9.3 mo for Pbo+Cabo (HR = 0.94; 95% CI: 0.74, 1.21; stratified log-rank P= 0.65) with overall response rates (ORR; confirmed) of 31% with Tela+Cabo vs 28% Pbo+Cabo, respectively. Overall survival was not mature at data cutoff. In a prespecified subgroup analysis in pts w/ prior ICI, mPFS was numerically longer w/ Tela+Cabo than Pbo+Cabo (11.1 vs 9.2 mo, respectively; unstratified HR = 0.77; 95% CI: 0.56, 1.06). In the Pbo+Cabo arm, mPFS was 9.2 mo for pts w/ prior ICI exposure and 9.5 mo for pts without, and ORR was 32% and 20%, respectively; if ICI included nivo/ipi, ORR was 37%. Rates of adverse events (AEs) were similar between arms.Grade 3-4 AEs occurred in 71% of Tela+Cabo pts and 79% of Pbo+Cabo pts and included hypertension (17% vs 18%) and diarrhea (15% vs 13%). Cabo was discontinued due to AEs in 10% of Tela+Cabo pts and 15% of Pbo+Cabo pts. Conclusions: The addition of Tela did not improve the efficacy of Cabo in mRCC in this study. Tela+Cabo was well tolerated with AEs consistent with known risks of both agents. The study provides valuable insight on efficacy outcomes of a contemporary population of pts w/ mRCC who receive Cabo in the 2/3L setting. Clinical trial information: NCT03428217.

Apparatus for skidding sensitivity testing of energetic materials

A remote-operated apparatus for testing the detonation sensitivity of energetic materials is detailed. Using an air ram and rotating disk, the normal force and transverse velocity of the impact plane are controlled independently, enabling the exploration of varying impact conditions over a wide parameter space. A microcontroller local to the apparatus is used to automate apparatus operation and ensure temporal alignment of the impacting ram head with the rotating disk. Calculation of the firing parameters and issuing of operational commands are handled by a remote computer and relayed to the local microcontroller for execution at the hardware level. Impact forces are taken from fast strain measurements obtained from gauges incorporated into the ram head. Infrared imaging of explosive samples provides insight into the peak thermal temperatures experienced at the sample surface during the impact event.

Disparities in Cancer Care and the Asian American Population

Asian Americans are the only racial/ethnic group in the U.S. for whom cancer is the leading cause of death in men and women, unlike heart disease for all other groups. Asian Americans face a confluence of cancer risks, with high rates of cancers endemic to their countries of origin due to infectious and cultural reasons, as well as increasing rates of "Western" cancers that are due in part to assimilation to the American diet and lifestyle. Despite the clear mortality risk, Asian Americans are screened for cancers at lower rates than the majority of Americans. Solutions to eliminate the disparity in cancer care are complicated by language and cultural concerns of this very heterogeneous group. This review addresses the disparities in cancer screening, the historical causes, the potential contribution of racism, the importance of cultural perceptions of health care, and potential strategies to address a very complicated problem. Noting that the health care disparities faced by Asian Americans may be less conspicuous than the structural racism that has inflicted significant damage to the health of Black Americans over more than four centuries, this review is meant to raise awareness and to compel the medical establishment to recognize the urgent need to eliminate health disparities for all. IMPLICATIONS FOR PRACTICE: Cancer is the leading cause of death in Asian Americans, who face cancers endemic to their native countries, perhaps because of infectious and cultural factors, as well as those faced by all Americans, perhaps because of "Westernization" in terms of diet and lifestyle. Despite the mortality rates, Asian Americans have less cancer screening than other Americans. This review highlights the need to educate Asian Americans to improve cancer literacy and health care providers to understand the important cancer risks of the fastest-growing racial/ethnic group in the U.S. Eliminating disparities is critical to achieving an equitable society for all Americans.

Outcomes of older men receiving docetaxel for metastatic hormone-sensitive prostate cancer

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Background: Most men who die of prostate cancer are older than 70 years, and the impact of therapy in this population is poorly defined. The ChemoHormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer (CHAARTED) randomized men of all ages with metastatic hormone-sensitive prostate cancer (mHSPC) to receive androgen deprivation therapy (ADT) with or without docetaxel. Methods: The results of CHAARTED showed an overall survival (OS) benefit for the addition of docetaxel to ADT in men with mHSPC. In a secondary analysis of this trial, we assessed patient characteristics and OS in patients ≥70 years (“older men”) versus <70 years (“younger men”) with Cox proportional hazards models. Additionally, we compared adverse events, therapy completion rate, and subsequent treatment patterns between these two groups using Chi-squared tests. Results: Of the 790 patients enrolled, 177 (22.4%) were ≥70 years. A greater proportion of older men had an impaired performance status (Eastern Cooperative Oncology Group 1-2: 36.7% vs. 28.6%, p=0.038) and prior local therapy (31.7% vs. 25.9%, p<0.001) compared to younger men. Docetaxel + ADT resulted in improved OS in both older and younger men (Hazard Ratio [HR] 0.45, 95%CI: 0.25-0.80 for older men; HR 0.71, 95%CI: 0.53-0.95 for younger men). This treatment benefit was seen for subgroups of older men with high volume disease (HR 0.43, 95%CI 0.23-0.79) and de novo metastatic disease (HR 0.36, 95%CI 0.19-0.69). A similar proportion of older and younger men completed all six cycles of docetaxel (82.6% vs. 87.1%, p=0.28). Rates of grade 3-5 adverse events were similar between older and younger men (36.8% of older men vs. 26.8% of younger men, p=0.69). The rate of any Grade 4-5 adverse events did not differ significantly between older and younger men (14.9% vs. 11.9%, respectively, p=0.46). In the control arm, a smaller proportion of older men received subsequent cancer treatments (34.4% vs. 51.5%, p=0.017) or subsequent docetaxel (25.6% vs. 37.6%, p=0.035) compared to younger men. Conclusions: In summary, older men with mHSPC who were eligible to participate in a clinical trial had similar OS benefit and clinical outcomes compared to younger men when receiving docetaxel chemotherapy + ADT. Oncologists should consider docetaxel chemotherapy as a favorable treatment option for older men with mHSPC who are fit for chemotherapy. Clinical trial information: NCT00309985.

Symptom burden, functional status, and clinical outcomes of hospitalized patients with advanced genitourinary cancers

42

Background: Patients with advanced genitourinary (GU) cancers are often hospitalized for complications of their cancer and symptom management. Yet, little is known about the symptom burden, functional status, and health care utilization of these patients. Methods: We prospectively enrolled patients with advanced cancer who experienced unplanned hospitalizations at an academic medical center. Upon admission, we asked patients to self-report their physical (Edmonton Symptom Assessment Scale-revised [ESAS-r]) and psychological (Patient Health Questionnaire-4 [PHQ-4]) symptoms. We also collected data from nursing assessments about impairments in activities of daily living (ADLs). We compared symptoms, functional impairment, readmissions, and overall survival (OS) between cancer types (dichotomizing GU cancers vs other cancer types) and within GU cancers (dichotomizing prostate cancer vs kidney/bladder/adrenal cancer) using univariate and multivariable regression analyses adjusted for age, sex, education, comorbidities, and time since advanced cancer diagnosis. Results: Among 971 patients enrolled, 106 (10.9%) had advanced GU cancers (39.6% prostate cancer, 32.1% kidney cancer, 25.5% bladder cancer, and 2.8% adrenal cancer). Compared to patients with other cancer types, patients with GU cancers were older (median: 69.0 vs 64.0 years, p < 0.001) and had more time since advanced cancer diagnosis (median: 14.0 vs 7.0 months, p < 0.001). In univariate analyses, a greater proportion of patients with GU cancers had an ADL impairment (57.5% vs 38.0%, p < 0.001) compared to other cancer types but the groups did not differ in their physical (Mean = 33.3 vs 32.6, p = 0.61) or depression (Mean = 4.1 vs 3.3, p = 0.05) symptoms. In multivariable models, patients with GU cancers had similar risk of readmission in 90 days (HR 1.31, p = 0.077), but worse survival (median OS: 102.0 days vs 133.5 days, p < 0.001; HR 1.27, p = 0.046). Within GU cancers, patients with kidney/bladder/adrenal cancer (vs. prostate cancer) were younger (median: 66.0 vs 74.0, p < 0.001) with less time since advanced cancer diagnosis (median: 9.0 vs 23.0 months, p = 0.012) but had no difference in symptoms or functional impairment. They were more likely to be admitted for symptom management (66% vs. 39% for prostate cancer, p = 0.026). Patients with kidney/bladder/adrenal cancer also had higher risk of readmission (HR 2.04, p = 0.043) but no difference in OS, compared to patients with prostate cancer. Conclusions: We found that hospitalized patients with advanced GU cancers had significantly greater functional impairment and worse survival compared to those with other cancer types, and those with kidney/bladder/adrenal cancer had significantly higher readmission risk compared to those with prostate cancer. These findings support the need to develop tailored supportive care for hospitalized patients with GU cancers.

Polymer, Additives, and Processing Effects on N95 Filter Performance

The current severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) pandemic has highlighted the need for personal protective equipment, specifically filtering facepiece respirators like N95 masks. While it is common knowledge that polypropylene (PP) is the industry standard material for filtration media, trial and error is often required to identify suitable commercial precursors for filtration media production. This work aims to identify differences between several commercial grades of PP and demonstrate the development of N95 filtration media with the intent that the industry partners can pivot and help address N95 shortages. Three commercial grades of high melt flow index PP were melt blown at Oak Ridge National Laboratory and broadly characterized by several methods including differential scanning calorimetry (DSC), X-ray diffraction (XRD), and neutron scattering. Despite the apparent similarities (high melt flow and isotacticity) between PP feedstocks, the application of corona charging and charge enhancing additives improve each material to widely varying degrees. From the analysis performed here, the most differentiating factor appears to be related to crystallization of the polymer and the resulting electret formation. Materials with higher crystallization onset temperatures, slower crystallization rates, and larger number of crystallites form a stronger electret and are more effective at filtration.

Longitudinal characterisation of haematological and biochemical parameters in cancer patients prior to and during COVID-19 reveals features associated with outcome

BACKGROUND

Cancer patients are at increased risk of death from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Cancer and its treatment affect many haematological and biochemical parameters, therefore we analysed these prior to and during coronavirus disease 2019 (COVID-19) and correlated them with outcome.

PATIENTS AND METHODS

Consecutive patients with cancer testing positive for SARS-CoV-2 in centres throughout the United Kingdom were identified and entered into a database following local governance approval. Clinical and longitudinal laboratory data were extracted from patient records. Data were analysed using Mann-Whitney U test, Fisher's exact test, Wilcoxon signed rank test, logistic regression, or linear regression for outcomes. Hierarchical clustering of heatmaps was performed using Ward's method.

RESULTS

In total, 302 patients were included in three cohorts: Manchester (n = 67), Liverpool (n = 62), and UK (n = 173). In the entire cohort (N = 302), median age was 69 (range 19-93 years), including 163 males and 139 females; of these, 216 were diagnosed with a solid tumour and 86 with a haematological cancer. Preinfection lymphopaenia, neutropaenia and lactate dehydrogenase (LDH) were not associated with oxygen requirement (O2) or death. Lymphocyte count (P < 0.001), platelet count (P = 0.03), LDH (P < 0.0001) and albumin (P < 0.0001) significantly changed from preinfection to during infection. High rather than low neutrophils at day 0 (P = 0.007), higher maximal neutrophils during COVID-19 (P = 0.026) and higher neutrophil-to-lymphocyte ratio (NLR; P = 0.01) were associated with death. In multivariable analysis, age (P = 0.002), haematological cancer (P = 0.034), C-reactive protein (P = 0.004), NLR (P = 0.036) and albumin (P = 0.02) at day 0 were significant predictors of death. In the Manchester/Liverpool cohort 30 patients have restarted therapy following COVID-19, with no additional complications requiring readmission.

CONCLUSION

Preinfection biochemical/haematological parameters were not associated with worse outcome in cancer patients. Restarting treatment following COVID-19 was not associated with additional complications. Neutropaenia due to cancer/treatment is not associated with COVID-19 mortality. Cancer therapy, particularly in patients with solid tumours, need not be delayed or omitted due to concerns that treatment itself increases COVID-19 severity.

Predicting new drug indications for prostate cancer: The integration of an in silico proteochemometric network pharmacology platform with patient-derived primary prostate cells

BACKGROUND

Drug repurposing enables the discovery of potential cancer treatments using publically available data from over 4000 published Food and Drug Administration approved and experimental drugs. However, the ability to effectively evaluate the drug's efficacy remains a challenge. Impediments to broad applicability include inaccuracies in many of the computational drug-target algorithms and a lack of clinically relevant biologic modeling systems to validate the computational data for subsequent translation.

METHODS

We have integrated our computational proteochemometric systems network pharmacology platform, DrugGenEx-Net, with primary, continuous cultures of conditionally reprogrammed (CR) normal and prostate cancer (PCa) cells derived from treatment-naive patients with primary PCa.

RESULTS

Using the transcriptomic data from two matched pairs of benign and tumor-derived CR cells, we constructed drug networks to describe the biological perturbation associated with each prostate cell subtype at multiple levels of biological action. We prioritized the drugs by analyzing these networks for statistical coincidence with the drug action networks originating from known and predicted drug-protein targets. Prioritized drugs shared between the two patients' PCa cells included carfilzomib (CFZ), bortezomib (BTZ), sulforaphane, and phenethyl isothiocyanate. The effects of these compounds were then tested in the CR cells, in vitro. We observed that the IC50 values of the normal PCa CR cells for CFZ and BTZ were higher than their matched tumor CR cells. Transcriptomic analysis of CFZ-treated CR cells revealed that genes involved in cell proliferation, proteases, and downstream targets of serine proteases were inhibited while KLK7 and KLK8 were induced in the tumor-derived CR cells.

CONCLUSIONS

Given that the drugs in the database are extremely well-characterized and that the patient-derived cells are easily scalable for high throughput drug screening, this combined in vitro and in silico approach may significantly advance personalized PCa treatment and for other cancer applications.

Current Status of MRI and PET in the NCCN Guidelines for Prostate Cancer

Prostate cancer (PCa) represents a significant source of morbidity and mortality for men in the United States, with approximately 1 in 9 being diagnosed with PCa in their lifetime. The role of imaging in the evaluation of men with PCa has evolved and currently plays a central role in diagnosis, treatment planning, and evaluation of recurrence. Appropriate use of multiparametric MRI (mpMRI) and MRI-guided transrectal ultrasound (MR-TRUS) biopsy increases the detection of clinically significant PCa while decreasing the detection of clinically insignificant PCa. This process may help patients with clinically insignificant PCa avoid the adverse effects of unnecessary therapy. In the setting of a known PCa, patients with low-grade disease can be observed using active surveillance, which often includes a combination of prostate-specific antigen (PSA) testing, serial mpMRI, and, if indicated, follow-up systematic and targeted TRUS-guided tissue sampling. mpMRI can provide important information in the posttreatment setting, but PET/CT is creating a paradigm shift in imaging standards for patients with locally recurrent and metastatic PCa. This article examines the strengths and limitations of mpMRI for initial PCa diagnosis, active surveillance, recurrent disease evaluation, and image-guided biopsies, and the use of PET/CT imaging in men with recurrent PCa. The goal of this review is to provide a rational basis for current NCCN Clinical Practice Guidelines in Oncology for PCa as they pertain to the use of these advanced imaging modalities.

Resolution of a High Grade and Metastatic BK Polyomavirus-Associated Urothelial Cell Carcinoma Following Radical Allograft Nephroureterectomy and Immune Checkpoint Treatment: A Case Report

BACKGROUND

BK viral infection in the posttransplant setting continues to cause serious morbidity with effects ranging from allograft nephropathy and dysfunction to urothelial malignancy.

RESULTS

In this report, we present a patient that developed BK-associated nephropathy and, 6 years later, locally advanced urothelial malignancy in the renal allograft with nodal, muscle, and extremity involvement. Following radical allograft nephroureterectomy, he was treated with palliative radiation and the immune checkpoint inhibitor atezolizumab. Follow-up imaging at 1 year demonstrated radiographic complete response.

CONCLUSIONS

This report supports the growing body of evidence supporting the association of urothelial malignancy and BK virus infection in renal transplant recipients. Further, it highlights the novel application of immune checkpoint inhibitors in the treatment of advanced posttransplant malignancy, in particular when the allograft is removed and the tumor is possibly of donor origin.

Viral integration in BK polyomavirus-associated urothelial carcinoma in renal transplant recipients: multistage carcinogenesis revealed by next-generation virome capture sequencing

BK polyomavirus (BKPyV)-associated cancer after transplantation has gained increasing attention. However, the role of BKPyV integration on oncogenesis is still unclear. In this study, next-generation virome capture sequencing of primary and metastatic tumors were performed in three patients with BKPyV-associated urothelial carcinoma after renal transplantation. As a result, a total of 332 viral integration sites were identified in the six tumors. Integration of BKPyV in both primary and metastatic tumors followed the mechanism of microhomology-mediated end joining mostly, since microhomologies between human and BKPyV genomes were significantly enriched in flanking regions of 84% of the integration sites. Viral DNA breakpoints were nonrandom and tended to assemble in large T gene, small T gene and viral protein 2 gene. There were three, one and one consensus integration sites between the primary and metastatic tumors, which affected LINC01924, eIF3c, and NEIL2 genes in the three cases respectively. Thus, we concluded that integration of BKPyV was a continuous process occurring in both primary and metastatic tumors, generating heterogenous tumor cell populations. Through this ongoing process, certain cell populations might have gained growth advantage or metastatic potential, as a result of viral integration either affecting the cellular genes where the viral DNA integrated to or altering the expression or function of the viral genes.

Durvalumab as neoadjuvant therapy for muscle-invasive bladder cancer: Preliminary results from the Bladder Cancer Signal Seeking Trial (BLASST)-2

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Background: There is no established neoadjuvant therapy (NAT) for patients (pt) with muscle invasive bladder cancer (MIBC) ineligible for cisplatin-based chemotherapy preceding radical cystectomy. Encouraging prospective data indicate PD-1/PD-L1 inhibitors, including pembrolizumab and atezolizumab, are safe and active as NAT for MIBC. Durvalumab (D), a PD-L1 inhibitor, is FDA approved for treating locally advanced or metastatic urothelial carcinoma following platinum-based chemotherapy. The safety and activity of D as NAT in MIBC have not been reported. Methods: We are conducting a single-center sequential multicohort trial (NCT03773666) of D alone (Cohort 1, N=10) and D plus the CD73 inhibitor oleclumab (Cohort 2, N=10) in cT2-T4aN0M0 MIBC pts who are RC candidates and are ineligible for or declined cisplatin-based chemotherapy. The primary endpoint is feasibility, defined as ≥7 of 10 pts receiving at least 1 dose of D followed by radical cystectomy without dose limiting toxicity (DLT) up to 12 wks post-RC. In Cohort 1, D is administered at 750mg IV Q2W for 3 cycles followed by RC 2-4 weeks after the last dose. Baseline and RC tissue and baseline and on-study blood are collected for correlative studies, including immunohistochemistry, genomics, transcriptomics, and metabolomics. Results: Cohort 1 has completed enrollment; ten pts were enrolled between Feb 2019 to Sept 2019. Median age was 67 (Range: 53-85) and 8 (80%) were men. All 10 pts completed 3 durvalumab doses. Eight pts completed planned RC with at least 12wk follow-up post-op to date. No DLTs were observed. One Grade 3 treatment-related adverse event (trAE) was reported (anemia), with no Grade 4 or higher trAE. Pathologic response (<pT2N0) was seen in 2 of 8 (25%) pts with pathologic complete response (pT0) in 1 (12.5%) pts. Updated safety and efficacy data from Cohort 1 will be presented. Conclusions: D appears to be feasible as NAT in MIBC with preliminary evidence for antitumor activity. Toxicities are consistent with data from other PD-1/PD-L1 inhibitor trials. Future cohorts will examine D-containing combination NAT strategies. Analysis of tissue and blood-based predictive biomarkers are ongoing. Clinical trial information: NCT03773666.

P6296The role of extracellular matrix protein 1 (ECM1) - a novel link between inflammation and cardiac fibrosis

Introduction

Cardiac fibrosis is a severe consequence of cardiovascular disease and aging, in which we currently have no effective treatments. The mechanisms underpinning the development of cardiac fibrosis remains poorly understood. Our preliminary data suggested extracellular matrix protein 1 (ECM1) is involved in cardiac fibrosis. We therefore aimed to investigate the role of ECM1 in several fibrotic cardiac diseases.

Methods

Young and ageing (3m/18m) male C57BL/6 mice, and primary mouse cardiac fibroblast (cFB) cultures, commercial human cardiac fibroblasts (Hu-cFB), human coronary artery endothelial cell (HCAEC)/smooth muscle cell (HCASMC), and human cardiac myocyte (HCM) cell lines were used. Young mice were subject to myocardial infarction (MI, 3-day/28-day, n=6/6), or pressure overload (TAC, 3-day/13-week, n=4/4). Left ventricle (LV) was collected at all time-points, and at 18m (ageing; n=3). Spleen and bone marrow was extracted from young control mice. Hu-cFB cells were treated with recombinant ECM1 (20ng/ml) for either 10, 30 or 50 min, or 48h. Immunoblotting was conducted on all samples, qPCR on LV tissue only, density gradient centrifugation and multicolour flow cytometry coupled with fluorescent ECM1 mRNA in-situ hybridisation (FISH-Flow) on bone marrow cells.

Results

ECM1 expression was upregulated in ageing LV (mRNA 2.2±0.1-fold, p=0.0002; protein 2.0-fold, p=0.0006), day-3 post-MI (mRNA, 4.9±2.0-fold, p=0.004; protein, 3.0-fold, p=0.004), a trend of ECM1 upregulation was observed at day-28 post-MI (mRNA, 13.2±12.0-fold, p=0.003; protein, 1.8-fold, p=0.2), but no change post-TAC. Both ERK1/2 and AKT phosphorylation was upregulated 10 min post-ECM1 treatment of Hu-cFBs (ERK1/2, 2.0-fold, p<0.0001; AKT, 1.9-fold, p<0.0001), and Collagen-I protein expression was upregulated 48h post-ECM1 treatment (1.9-fold, p=0.004). ECM1 protein was not expressed in cFB, Hu-cFB, HCAEC, HCASMC or HCM, however ECM1 protein was highly expressed in spleen and bone marrow; to a greater extent in granulocytes compared to monocytes (p=0.004). tSNE analysis of ECM1 mRNA FISH-Flow revealed ECM1+ are highly granular, moderate to large in size, and express (to varying levels) CD45, CD11b, CD11c, F4/80, Ly6-C, Ly-6G, and FcεrI-α. However ECM1+ cells did not express markers indicative of smaller cells (CD3 or MHC II).

Conclusions

These data demonstrate that ECM1 plays a role in ageing and post-MI fibrosis. Although ECM1 was not produced by resident cardiac cells, it was highly expressed in spleen and bone marrow; specifically, large, granular bone marrow cell sub-types such as granulocytes and/or macrophages. Our data suggest ECM1 is expressed by cardiac infiltrating leukocytes to provoke fibroblast collagen expression in a disease specific manner; potentially via the ERK1/2 and/or AKT pathway activation. Therefore, ECM1 warrants further investigation, and may be a promising target for the treatment of fibrotic cardiac diseases.

Acknowledgement/Funding

John hunter hospital charitable trust, Hunter medical research institute (HMRI) grants

Safety and efficacy of nivolumab plus ipilimumab (NIVO+IPI) in patients with advanced renal cell carcinoma (aRCC) with brain metastases: Interim analysis of CheckMate 920

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Background: Previous clinical trials of patients (pts) with aRCC, including CheckMate 214, have mostly excluded pts with brain metastases. However, antitumor activity in pts with brain metastases has been observed in pts with melanoma treated with NIVO 1 mg/kg + IPI 3mg/kg and pts with non-small cell lung cancer treated with NIVO 240 mg + IPI 1mg/kg. CheckMate 920 is an ongoing, phase 3b/4 clinical trial of NIVO + IPI treatment in pts with aRCC with a high unmet medical need. Here, we present the safety and efficacy interim results for the cohort of pts with brain metastases. Methods: Pts with previously untreated aRCC of any histology, with asymptomatic brain metastases (not on corticosteroids or receiving radiation), and Karnofsky performance status ≥70% were assigned to treatment with NIVO 3 mg/kg + IPI 1 mg/kg every 3 weeks for 4 doses, followed by NIVO 480 mg every 4 weeks. Pts were treated until disease progression, unacceptable toxicity, or for a maximum of 2 years. The primary endpoint was the incidence of high-grade immune-mediated adverse events (IMAEs). Key secondary endpoints included progression-free survival (PFS) and objective response rate (ORR) by RECIST v1.1 per investigator. Exploratory endpoints included additional safety analyses and overall survival (OS). Results: Overall, 28 patients were enrolled in the brain metastases cohort. With a minimum follow-up of 6.47 months, grade 3-4 IMAEs within 100 days of last dose were reported in 6 cases. The grade 3-4 IMAEs observed in ≥ 1 patient were diarrhea, colitis, diabetic ketoacidosis, immune-mediated hepatitis, hypophysitis, and rash of any type (n = 1 each). No treatment-related grade 5 IMAEs were reported. ORR by RECIST v1.1 per investigator in all treated subjects was 28.6% (95% CI 13.2–48.7). Median PFS in all treated subjects was 9.0 months (95% CI 2.9–not estimable [NE]). Median OS has not been reached (95% CI 13.1–NE). Conclusions: In pts with aRCC and brain metastases who are often excluded from clinical trials, NIVO + IPI treatment showed a safety profile consistent with previous reports of this dosing regimen, with encouraging antitumor activity. Clinical trial information: NCT02982954.

Prospective Comprehensive Genomic Profiling of Primary and Metastatic Prostate Tumors

PURPOSE

Comprehensive genomic profiling (CGP) is increasingly used for routine clinical management of prostate cancer. To inform targeted treatment strategies, 3,476 clinically advanced prostate tumors were analyzed by CGP for genomic alterations (GAs) and signatures of genomic instability.

METHODS

Prostate cancer samples (1,660 primary site and 1,816 metastatic site tumors from unmatched patients) were prospectively analyzed by CGP (FoundationOne Assay; Foundation Medicine, Cambridge, MA) for GAs and genomic signatures (genome-wide loss of heterozygosity [gLOH], microsatellite instability [MSI] status, tumor mutational burden [TMB]).

RESULTS

Frequently altered genes were TP53 (44%), PTEN (32%), TMPRSS2-ERG (31%), and AR (23%). Potentially targetable GAs were frequently identified in DNA repair, phosphatidylinositol 3-kinase, and RAS/RAF/MEK pathways. DNA repair pathway GAs included homologous recombination repair (23%), Fanconi anemia (5%), CDK12 (6%), and mismatch repair (4%) GAs. BRCA1/2, ATR, and FANCA GAs were associated with high gLOH, whereas CDK12-altered tumors were infrequently gLOH high. Median TMB was low (2.6 mutations/Mb). A subset of cases (3%) had high TMB, of which 71% also had high MSI. Metastatic site tumors were enriched for the 11q13 amplicon (CCND1/FGF19/FGF4/FGF3) and GAs in AR, LYN, MYC, NCOR1, PIK3CB, and RB1 compared with primary tumors.

CONCLUSION

Routine clinical CGP in the real-world setting identified GAs that are investigational biomarkers for targeted therapies in 57% of cases. gLOH and MSI/TMB signatures could further inform selection of poly (ADP-ribose) polymerase inhibitors and immunotherapies, respectively. Correlation of DNA repair GAs with gLOH identified genes associated with homologous recombination repair deficiency. GAs enriched in metastatic site tumors suggest therapeutic strategies for metastatic prostate cancer. Lack of clinical outcome correlation was a limitation of this study.

Prediction and monitoring of relapse in stage III melanoma using circulating tumor DNA

BACKGROUND

The advent of effective adjuvant therapies for patients with resected melanoma has highlighted the need to stratify patients based on risk of relapse given the cost and toxicities associated with treatment. Here we assessed circulating tumor DNA (ctDNA) to predict and monitor relapse in resected stage III melanoma.

PATIENTS AND METHODS

Somatic mutations were identified in 99/133 (74%) patients through tumor tissue sequencing. Personalized droplet digital PCR (ddPCR) assays were used to detect known mutations in 315 prospectively collected plasma samples from mutation-positive patients. External validation was performed in a prospective independent cohort (n = 29).

RESULTS

ctDNA was detected in 37 of 99 (37%) individuals. In 81 patients who did not receive adjuvant therapy, 90% of patients with ctDNA detected at baseline and 100% of patients with ctDNA detected at the postoperative timepoint relapsed at a median follow up of 20 months. ctDNA detection predicted patients at high risk of relapse at baseline [relapse-free survival (RFS) hazard ratio (HR) 2.9; 95% confidence interval (CI) 1.5-5.6; P = 0.002] and postoperatively (HR 10; 95% CI 4.3-24; P < 0.001). ctDNA detection at baseline [HR 2.9; 95% CI 1.3-5.7; P = 0.003 and postoperatively (HR 11; 95% CI 4.3-27; P < 0.001] was also associated with inferior distant metastasis-free survival (DMFS). These findings were validated in the independent cohort. ctDNA detection remained an independent predictor of RFS and DMFS in multivariate analyses after adjustment for disease stage and BRAF mutation status.

CONCLUSION

Baseline and postoperative ctDNA detection in two independent prospective cohorts identified stage III melanoma patients at highest risk of relapse and has potential to inform adjuvant therapy decisions.

The evolution and understanding of skeletal complication endpoints in clinical trials of tumors with metastasis to the bone

Bone metastases are a frequent complication of solid tumors, leading to significant skeletal sequelae that negatively impact quality of life and survival. Prevention and management of skeletal-related complications are critical treatment goals in oncology. Endpoints used in clinical trials to evaluate skeletal-related complications have evolved. In contrast to single measures of bone health, contemporary clinical trial endpoints reflect composite measures of skeletal-related complications, and increasingly also survival. In addition, key symptomatic components, which are more reflective of quality of life and the patient experience, are being incorporated. Given the evolution and resulting diversity of the endpoints being used in pivotal trials, it is becoming increasingly relevant to clarify the utility and the potential clinical impact of these measures not only within the context of trials but also in the real-world setting. Here, we describe the development and evolution of skeletal endpoints used in trials, and discuss their clinical relevance.

A phase II, multicenter, single-arm trial of CV301 plus atezolizumab (Atezo) in locally advanced (unresectable) or metastatic urothelial cancer (UC)

TPS494

Background: Anti-PD1/PD-L1 can achieve durable responses in advanced UC but most patients (pts) do not respond. Combination strategies with agents that “prime” the immune system may improve outcomes. CV301 comprises two recombinant poxviruses, Modified Vaccinia Ankara (MVA) and Fowlpox (FPV), encoding the human transgenes for CEA, MUC-1, and a Triad of Co-stimulatory Molecules (TRICOM: ICAM-1, LFA-3, and B7-1). MVA-CV301 is used for priming doses and FPV-CV301 is used for booster doses to achieve a heterologous prime boost regimen. In preclinical studies, BN-platform vaccine plus PD1/PD-L1 inhibitors exhibited synergistic anti-tumor efficacy, T-cell infiltration, and PD-L1 upregulation in tumors. CEA and MUC-1 are expressed, in 41-90% and 55-91% of any stage UC, respectively, and in ~100% of metastatic UC. An ongoing Phase Ib trial of CV301 plus anti-PD-1 agent has demonstrated a similar safety profile to anti-PD-1 monotherapy with only mild vaccine-related adverse events (AEs). Methods: This is a Phase 2, single-arm, multi-institutional trial designed to study CV301 plus atezo as 1st-line treatment in pts with advanced UC ineligible for cisplatin-based chemotherapy regardless of PD-L1 (Cohort 1) and as salvage treatment in pts with UC progressing after platinum-based chemotherapy (Cohort 2). MVA-CV301 is given subcutaneously (SC) on Days 1 and 22 and FPV-CV301 SC every 21 days for 4 doses, then every 6 weeks until 6 months, then every 12 weeks until 2 years. Atezo 1200mg is given every 21 days. Primary endpoint is objective response rate (ORR; RECIST 1.1). Secondary endpoints: immune response, OS, PFS, response duration, AEs. Tumor and serial blood samples will be collected for biomarker analyses; 1-sided α is 0.025/cohort in this design. With a 2-stage design, success criteria are based on historic ORR (H0) and alternative ORR (H1) with ≥70% power. For Cohort 1, assuming H0 = 0.23, H1 = 0.43, then Cohort 1 sample size N1= 14, responders required at stage 1 to continue R1≥3, total accrual goal N = 33, total responders to reject H0, R≥13. For Cohort 2, assuming H0 = 0.15, H1 = 0.33, then N1= 13, R1≥2, N = 35, R≥10. Accrual has begun; completion is expected within 1 year. Clinical trial information: NCT03628716.

CB-839, a glutaminase inhibitor, in combination with cabozantinib in patients with clear cell and papillary metastatic renal cell cancer (mRCC): Results of a phase I study

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Background: Glutaminase (GLS) is a key enzyme that controls glutamine utilization, a metabolic pathway upregulated in RCC and important for tumor proliferation and survival. CB-839 is a first-in-clinic, small molecule, reversible, oral GLS inhibitor that synergizes with cabozantinib (Cabo), a VEGFR2/MET/AXL inhibitor, in preclinical RCC models to inhibit metabolic pathways and enhance anti-tumor activity. Cabo monotherapy is associated with a 17% overall response rate (ORR) for clear cell (cc) mRCC (Choueiri et al. Lancet Oncol. 2016). Here we present findings from a Phase 1 study cohort evaluating the safety, efficacy, and recommended Phase 2 dose (RP2D) of CB-839 + Cabo in patients (pts) with mRCC as 2L+ therapy. Methods: Eligible pts had mRCC with cc or papillary histology, ECOG 0-1, RECIST measurable disease, and, for cc pts, treatment with ≥1 prior anti-VEGF therapy. Escalating doses of CB-839 (600-800 mg PO BID) plus Cabo (60 mg PO QD) were evaluated using a 3+3 design. Tumor response was assessed per RECIST 1.1 every 8 wks. Results: The CB-Cabo cohort enrolled 13 pts with a median 3 (range, 0-7) prior lines of therapy. No maximum tolerated dose was reached; 800 mg was selected as the CB-839 RP2D. The most common treatment-related AEs (occurring in >25% of pts) were diarrhea (62%), decreased appetite (46%), ALT increased (39%), fatigue (39%), AST increased (31%), nausea (31%), and rash (31%); Gr ≥3 treatment-related AEs included diarrhea, hypertension, platelet count decreased, and hallucination (n=1 each). Among 12 evaluable pts, ORR was 42% and disease control rate (DCR = complete response + partial response [PR] + stable disease [SD]) was 100%: 42% (5/12) PR, 58% (7/12) SD. Among 10 evaluable cc mRCC pts, 50% (5/10) had PRs, 50% (5/10) SDs. As of Sept 24, 2018, 5 pts received >12 months treatment; 4 remain on study. Conclusions: CB-839 plus Cabo showed encouraging clinical activity and tolerability in heavily pretreated mRCC pts, with response rates for cc mRCC (50% ORR, 100% DCR) comparing favorably to historical Cabo monotherapy. A randomized Phase 2 study of CB-839 + Cabo vs. Cabo + placebo in cc mRCC is ongoing. (CANTATA; NCT0342821) Clinical trial information: NCT02071862.

Spatial and temporal variation of three biomarkers in Mytilus edulis

Environmental conditions and xenobiotic exposure can be sources of stress to living organisms. Biological markers are measurable indicator of changes which may happen at any biological level and which can be considered an early warning signal of some biological or environmental state or condition. A structured field study was undertaken to investigate the relationship between three biomarker assays and the spatial and temporal variation of each biomarker in samples of Mytilus edulis. The three biomarkers were the neutral red retention assay, micronucleus assay and comet assay, which indicate damage at different cellular/molecular levels. Three sites in Poole Harbour, an area on the South coast of the UK were sampled on six separate occasions at least three weeks apart. The results for the comet assay showed a significant difference between sites and between sampling dates whereas the results for the other two assays did not show a significant difference for either factor. There was no significant correlation between the results of any pair of the three biomarkers. The results of the micronucleus assay showed a significant correlation with water temperature. This temperature effect, as well as induced repair, may contribute to explain the lack of a strict correspondence between pollution gradients and biomarkers responses.