PRINT: Prostate cancer intensive, non-cross reactive therapy for CRPC—Early observations of efficacy

e17575

Background: Optimal sequencing of therapeutic agents in mCRPC remains debated, but the standard approach is to treat with one agent until resistance is met before switching. PRINT explores the efficacy of treating mCRPC with a rapidly-cycling, non-cross reactive regimen as a way to more effectively treat intrinsic heterogeneity, delay or prevent drug resistance, and minimize treatment toxicity. Methods: Patients received treatment with 3 consecutive treatment modules, each lasting 12 weeks: 1. abiraterone acetate 1000 mg PO daily + prednisone 5 mg PO BID; 2. cabazitaxel 20 mg/m2 IV + carboplatin AUC 4 IV q3 weeks; 3. enzalutamide 160 mg PO daily + radium-223 50 kBq/kg IV q4 weeks (in those with bone metastases). Upon completion of the 9-month regimen, patients are followed on ADT alone. Primary endpoint for the study is PSA or radiographic time to progression (TTP). Results: From 3/2017 to 1/2020, 38 of 40 planned men with mCRPC were enrolled, 28 patients have completed the 9-month study regimen and evaluable for TTP analysis. With median follow up of 54+ weeks, median time to PSA progression after therapy completion is 14.7+ weeks (95%CI; 5.5-23.9+ weeks). PSA response rates showed successive improvements with each sequential treatment module (Table). Eight patients (21.1%) continue on post-study surveillance with ADT alone, two of which have remained off any mCRPC agents for over a year (82+ weeks, 79+ weeks). In patients needing to restart therapy, experience with efficacy and tolerability of each agent while on the study, has helped inform subsequent mCRPC drug selection. The study regimen is well-tolerated, with few grade 3/4 AE’s: hyperglycemia (15.8%), diarrhea (5.3%), anemia (2.6%), fatigue (2.6%), neutropenia (2.6%), and thrombocytopenia (2.6%). Conclusions: Treatment of mCRPC with a rapidly-cycling non-cross reactive regimen demonstrates significant antitumor benefits, with potential for long-term suppression of disease. Further longitudinal follow up will determine if PRINT delays progression compared with standard approaches. Clinical trial information: NCT02903160 . [Table: see text]

Clinical efficacy of immunotherapy for the treatment of solid tumors in patients with chronic kidney disease

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Background: Regulatory T cells play a key role in protecting kidney cells from ischemic injury. Immune checkpoint inhibitors (ICIs) may increase the risk of acute kidney injury via inhibition of regulatory T cells [1, 2]. Prospective clinical trials have largely excluded patients with chronic kidney disease (CKD); thus, we have limited knowledge of the safety and efficacy of ICI in these patients. Herein, we hypothesize that patients with CKD receiving ICIs have worse clinical outcomes. Methods: This single-institution retrospective cohort study included adult patients with solid tumors who were treated with ICIs at The Mount Sinai Hospital between 2011 and 2017. Clinical endpoints [response to treatment, progression of disease (POD) on treatment, mortality] were compared between patients with and without CKD using multivariate logistic regression. Odds ratios were controlled for demographics, primary tumor type, presence of cardiovascular comorbidities, smoking status, incidence of renal adverse events, and a composite of stage of illness with indication for treatment [localized—neoadjuvant, localized—adjuvant, regionally advanced, metastatic disease]. Data were analyzed using R version 3.5.1 with the following packages: readr, dplyr, broom, lubridate, tableone. Results: 420 patients met inclusion criteria: 399 patients without CKD and 21 patients with CKD. Cohorts are well matched for demographics, smoking status, stage/indication for treatment. The CKD cohort has a higher proportion of patients with urothelial cancer compared to patients without CKD (33% vs 11%) as well as a higher proportion of patients with HTN (81% vs 53%), HF (14% vs 3%), and DM (48% vs 21%). There was no statistical difference in odds of response to treatment [OR 0.76, 95% CI 0.26-2.23], POD [OR 0.42, 95% CI 0.15-1.17], or mortality [OR 2.05, 95% CI 0.71-5.96] between the CKD and non-CKD cohort. Conclusions: The data suggest the presence of CKD is not associated with worse clinical outcomes in cancer patients treated with ICIs. As a small retrospective study, the conclusions are hypothesis-generating but support continued use of immunotherapy in CKD in clinical practice and the inclusion of patients with CKD in immunotherapy clinical trials to further clarify safety and efficacy. [Table: see text]

What happens at radiographic disease progression in patients with metastatic cancer receiving immune checkpoint inhibitors? A single institution analysis

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Background: Immune checkpoint inhibitors (ICIs) are widely adopted for multiple indications across various malignancies. Despite the surge in their use, what occurs at radiographic progression (rPOD) remains poorly characterized. Herein, we describe patients at our institution that experienced rPOD on ICIs. Methods: We retrospectively reviewed charts of patients (pts) with solid tumors that received at least 2 doses of ICI at our institution from 12/01/2010 to 04/25/2017. Patients’ demographic data, medical history, ICI course, and outcomes were recorded. Characteristics at rPOD included change in tumor size by metastatic site, symptoms, and hospital utilization. Additionally, we characterized outcomes of pts who continued ICIs after rPOD. Fisher’s exact test was performed to identify potential clinical predictors of hospitalization at rPOD. Results: Of the 361 evaluable pts, 238 experienced rPOD. In this cohort, the most common primary sites of disease are: genitourinary (24%), thoracic (24%), skin (21%), and hepatobiliary (15%). At rPOD, 71 (30%) patients were hospitalized within 30 days, with infection (27%) and pain (18%) being the most common reasons. Median survival of pts with hospitalization was 2 months (mos; 95% CI: 0-4), compared to 10 months (95% CI: 8-12) for those not hospitalized (p<0.001). Forty-six (19%) pts continued ICI treatment after rPOD (median duration = 2.8 mos), with eleven (5%) pts continuing for at least 6 months (median duration = 8 mos). Conclusions: In our study of real-world cancer pts treated with ICI, a higher than expected proportion was hospitalized within 30 days after rPOD, and this population had a worse overall survival compared to those that were not. A subgroup of pt with rPOD did not experience clinical progression, and thus treatment was continued, although further benefit was limited to a small subset. Further studies are needed to better understand the underlying mechanism to identify those who benefits from treatment beyond rPOD. [Table: see text]

Effect of concurrent beta-blocker use in patients receiving immune checkpoint inhibitors for advanced solid tumors

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Background: Stress-induced adrenergic signaling suppresses the immune system. In animal model systems, pharmacological beta-blockade stimulated CD8+ T-cell activity, and further, it improved clinical activity of immune checkpoint inhibitors (ICI) in inhibiting tumor growth. Herein, we investigate the effect of beta blockers (BB) on clinical outcomes of patients receiving ICI in advanced solid tumors. Methods: We retrospectively evaluated patients with solid tumors treated with at least 2 doses of ICI at our institution from December 2010 to April 2017. The primary outcome was disease control rate (DCR), as defined by radiographic complete response, partial response, or stable disease, by RECIST 1.1 criteria. The primary predictor was use of BB (β1-selective BB vs. no BB; non-selective BB vs no BB). The primary predictive variable was analyzed using multivariate logistic regression model controlling for several parameters including patient demographics, co-morbidities, ECOG performance status, and tumor type and location of metastases. All tests were two-sided at the significant level of 0.05. Results: We identified 298 evaluable patients with median age of 66.5 (31-95). Of these patients, 200 (67%) did not use BB, 75 (25%) used β1-selective BB, and 23 (8%) used non-selective BB. In multivariate analysis, use of β1-selective BB was significantly associated with improved DCR compared to no BB (ORR 2.43, 95% CI 1.31-4.51, P = 0.005), while use of non-selective BB was not associated with improved DCR (ORR 1.71, 95% CI 0.65-1.47, P = 0.27). Conclusions: The concurrent use of BB may enhance the clinical activity of ICI, particularly β1-selective BB. Our findings warrant further investigation to understand the interaction of β1- and β2-adrenergic signaling and antitumor immune activity, and potentially explore a combination strategy of ICI and BB.

Smoking status and immunotherapy outcomes in smoking-associated cancers

e15097

Background: Improved immunotherapy (IO) outcomes have been observed among non-small cell lung cancer patients with a current or former smoking history. This is thought to be a consequence of increased immunogenic mutation burden among smoking-related cancers. We set out to explore the association between smoking status and immunotherapy outcomes in lung and other smoking-associated cancers. Methods: This was a retrospective analysis of 200 consecutive patients with advanced, smoking-associated solid tumor types, treated with single-agent anti-PD1/PDL1 therapy at a single center between July 2014 and February 2018. The primary outcome was overall survival from date of IO initiation. The secondary outcome was overall response, defined as radiographic complete response or partial response, by RECIST 1.1 criteria. The primary predictor was smoking status (former/current smoker vs. never smoker). The primary and secondary outcomes were analyzed using multivariable Cox proportional hazards models and multivariable logistic regression models, respectively. Models were adjusted for age and sex, and stratified by cancer type. Results: The majority of patients were male (64%) with a history of smoking (72%); the average age was 67.1 ± 11.4 years. Cancer types represented were: non-small cell lung cancer (NSCLC, N = 81), hepatocellular carcinoma (HCC, N = 41), urothelial carcinoma (BLCA, N = 39), head and neck squamous cell carcinoma (HNSC, N = 21), and renal cell carcinoma (RCC, N = 18). Over a median follow-up of 11.3 months (range 0.5-53.2), there were 96 deaths and 27% of evaluable patients achieved radiographic response. Response was not evaluable in 27 patients. In multivariable regression analysis, smoking status was not significantly associated with overall survival nor overall response in any cancer type examined (Table). Conclusions: Smoking status was not associated with outcomes in our cohort of IO-treated patients with smoking-associated cancers, though sample size was limited. [Table: see text]

Predicting toxicity-related docetaxel discontinuation and survival in metastatic castration-resistant prostate cancer (mCRPC) using open phase III trial data

75

Background: Docetaxel (D) is widely used in mCRPC, however its optimal use remains unclear in the current treatment (tx) landscape. Biomarkers to predict D toxicity may help inform tx selection. Methods: Through Project Data Sphere, we pooled patient (pt) data from the control arms of three frontline mCRPC trials: ASCENT2, VENICE, and MAINSAIL. Tx in each control arm consisted of D 75mg/m2 every 21 days + prednisone 5mg twice/day. The primary outcome was occurrence of toxicity-related D discontinuation (TRDD). Reasons for D discontinuation were recorded and demographic/clinical data were considered in a competing risks regression (CRR) to develop a model to predict TRDD. Cumulative incidence (CI) of TRDD was estimated after accounting for the occurrence of competing events (death or progression). This model was used to build a risk calculator to predict TRDD, the output of which was used in a classification and regression tree (CART) to identify 3 risk groups. Overall survival (OS) for the pooled cohort and for each risk group was assessed via the Kaplan-Meier (KM) method. Results: 1568/1600 pts had complete data and were studied. 41.4% died from any cause during the trials; median follow-up for survivors was 12.1 months (mos). Median OS for the entire cohort was 21 mos. CRR yielded the following significant factors that were included in the predictive model and risk calculator: age, ECOG performance status, AST, bilirubin, use of analgesics, and diagnoses of diabetes and chronic kidney disease. Pooled CI of TRDD was 19% after accounting for competing events (death, 474 pts; progression, 59 pts) within 12 mos of starting tx. CART analysis defined the risk groups as low (model-derived TRDD risk ≤24%), intermediate (25-64%), and high (≥65%). In each risk group, probability of TRDD during tx was 14%, 58%, and 79%, and median OS was 24 mos, 20 mos, and 13 mos, respectively (p<0.001). Conclusions: Tx selection in mCRPC remains a challenge. Our model can help clinicians balance D toxicity and efficacy in order to make better-informed decisions.

Characterizing patterns of disease progression in patients with genitourinary cancers treated with immune checkpoint inhibitors

482

Background: Despite the widespread use of immune checkpoint inhibitors (ICIs), patterns of disease progression (POD) are poorly characterized. We aim to define these characteristics in patients (pts) with advanced urothelial carcinoma (UC) and renal cell carcinoma (RCC) treated with ICIs. Methods: We retrospectively reviewed charts of pts with advanced UC and RCC who received at least 2 ICI doses at our institution from 12/1/10 – 10/31/18. Demographics, medical history, ICI course, toxicity, and outcomes were recorded. Characteristics at the time of radiographic POD including location of metastases (mets), symptoms (sx), and hospitalization details were collected. Fisher’s exact test was used to study differences in pts with and without hospitalization at POD. Results: Of the 71 pts identified (UC N=53; RCC N=18), 59 pts had POD. At POD, 19 (32.2%) pts had new sites of disease involvement, while the remaining pts (N=40, 67.8%) had progression only at previously known sites of disease. Fourty-six (78.0%) pts had sx at POD: 1 sx (N=19, 32.2%), 2 sx (N=13, 22.0%), 3+ sx (N=14, 23.7%). Pain was the most common sx at POD (N=32, 54.2%), followed by loss of energy (N=18, 30.5%), and loss of appetite (N=14, 23.7%). Twenty-five (42.4%) pts were hospitalized at POD, most commonly for sepsis (N=8, 32%). No clinical factors were identified to predict for pts being hospitalized at POD. Conclusions: In our review of GU cancer patients on ICIs, a large proportion of pts reported clinical sx at POD, pain being the most frequent. Furthermore, a substantial number of pts were hospitalized at POD, most commonly for sepsis. Thus, further studies are warranted to confirm these findings, and potentially identify strategies to optimize patients’ quality-of-life and reduce rates of hospitalizations at the time of POD on ICIs.

PRINT: Prostate cancer intensive, non-cross reactive therapy for CRP—Early observations of efficacy

89

Background: Optimal sequencing of therapeutic agents in mCRPC remains debated, but the standard approach is to treat with one agent until resistance is met before switching. PRINT explores the efficacy of treating mCRPC with a rapidly-cycling, non-cross reactive regimen as a way to more effectively treat intrinsic heterogeneity, delay/prevent drug resistance, and minimize toxicity. Methods: Enrolled patients all received 3 consecutive treatment modules, each 12 weeks: 1. abiraterone acetate 1000 mg PO daily + prednisone 5 mg PO BID; 2. cabazitaxel 20 mg/m2 IV + carboplatin AUC 4 IV q3 weeks; 3. enzalutamide 160 mg PO daily + radium-223 55 kBq/kg IV q4 weeks (in those with bone metastases). Upon completion of the 9-month regimen, patients are followed on ADT alone. Primary endpoint for the study is PSA or radiographic time to progression (TTP). Results: From 3/2017 to 10/2019, 35 of 40 planned men with mCRPC were enrolled, 25 patients have completed the 9-month study regimen and evaluable for TTP analysis. With median follow up of 52 weeks, median time to PSA progression after therapy completion is 15.5 weeks (95%CI; 5-26.1+ weeks). PSA response rates show successive improvements with each sequential treatment module (Table). Six (24%) patients continue on post-study surveillance with ADT alone, two of which have remained off any mCRPC agents for over a year (64+ weeks, 54+ weeks). In patients needing to restart therapy, experience with efficacy and tolerability of each agent while on the study, has helped inform subsequent mCRPC drug selection. The study regimen is well-tolerated, with few grade 3/4 AE’s: hyperglycemia (14.3%), diarrhea (5.7%), anemia (2.9%), fatigue (2.9%), neutropenia (2.9%), and thrombocytopenia (2.9%). Conclusions: Treatment of mCRPC with a rapidly-cycling non-cross reactive regimen demonstrates significant antitumor benefits, with potential for long-term suppression of disease. Further longitudinal follow up will determine if PRINT delays progression compared with standard approaches. Clinical trial information: NCT02903160. [Table: see text]

Type, timing, and risk factors associated with immune-related adverse event development in patients with advanced genitourinary cancers treated with immune checkpoint inhibitor

480

Background: Immune related adverse events (IRAEs) with immune checkpoint inhibitor (ICI) therapy are well recognized, but predictors for IRAEs are not well defined. We aim to characterize the type, timing, and clinical risk factors associated with (w/) IRAEs in ICI-treated, advanced urothelial carcinoma (UC) and renal cell carcinoma (RCC) patients (pts). Methods: We retrospectively reviewed charts of pts w/ advanced UC and RCC who received at least 2 ICI doses at our institution from 1/1/10 to 10/31/18. Patient baseline characteristics, treatment course, and clinical outcomes were collected. IRAEs were identified and graded (GR) based on CTCAE (v.4.0). Fisher’s exact test was used to study the differences between pts w/ versus without IRAE. Results: Of the 71 pts identified (UC n = 53; RCC n = 18), 27 pts (38%) developed IRAEs with 42 total events (38% GR1, 60% GR2, and 2% GR≥3) [table]. The majority of pts with dermatitis (70%) also developed a secondary, systemic IRAE(s). Systemic steroid (SS) was required in 17 events. The median time to any IRAE was 17.5 weeks (w, range 1-93). ECOG ≤ 1 predicted IRAE development (p < 0.05). No other characteristics (demographics, co-morbidities, metastatic sites, ICI type, line of therapy, and duration of ICI > 12w) were associated with IRAE. Conclusions: In our study, good function status is associated with the development of IRAE. Time to IRAE ranged from immediately to 93w after initiating ICI. Clinical validation with additional datasets will be needed to confirm these findings. [Table: see text]

Synthesis, properties and photovoltaic performance in dye-sensitized solar cells of three meso-diphenylbacteriochlorins bearing a dual-function electron-donor

Synthesis, properties, and photovoltaic performance of three new air-stable, meso-biphenylbacteriochlorins bearing a dual-function donor are reported.

Telemedicine-Enabled Clinical Trial of Metformin in Patients With Prostate Cancer

PURPOSE

Clinical trials are critical to informing cancer care but often are hampered by slow accrual and lack of generalizability because of poor geographic accessibility. We tested the feasibility of replacing onsite study visits with telemedicine visits in a prospective clinical trial.

METHODS

Castration-naïve patients with prostate cancer and a rising serum prostate-specific antigen after definitive local therapy were eligible. Patients were required to have a single onsite visit for enrollment. Study treatment consisted of oral metformin 850 mg daily for 1 month followed by 850 mg twice daily for 5 months. Telehealth video visits (televisits) were conducted monthly by using a Health Insurance Portability and Accountability Act-compliant smartphone application. The primary objective was to determine the feasibility of telemedicine-enabled study visits. Secondary objectives were defining safety, anticancer activity, quality of life, and patient satisfaction.

RESULTS

Fifteen patients with a median age of 68 years (range, 57 to 83 years) and median one-way driving time to the study center of 71 minutes (range, 12 to 147 minutes) were enrolled. The patients completed 84 eligible televisits (completion rate, 100%; 95% CI, 0.80 to 1). Diarrhea was the most common adverse event but was limited to grade 1 in severity; a single patient experienced grade ≥ 3 adverse events. Seven patients (46.7%; 95% CI, 24.8% to 69.9%) had a ≤ 20% increase in prostate-specific antigen relative to baseline. Patients agreed or strongly agreed that they would participate in a telemedicine-enabled clinical trial in the future.

CONCLUSION

To our knowledge, this interventional oncology clinical trial is the first to be conducted through telemedicine. Telemedicine-enabled trials are feasible and may overcome geographic barriers to trial participation. Metformin was generally well tolerated but associated with modest anticancer activity.

PRINT: Prostate cancer intensive, non-cross reactive therapy for CRPC—Early observations of feasibility and efficacy

310

Background: Optimal sequencing of approved therapeutic agents in mCRPC is not known. The standard approach, is to treat until resistance then switch. The PRINT trial explores the efficacy of treating mCRPC with a rapidly-cycling, non-cross reactive regimen as a way to more effectively treat an intrinsically heterogeneous disease, to delay or prevent drug resistance, and minimize treatment toxicity. Methods: Patients were treated with 3 consecutive treatment modules, each of 12 weeks' duration: 1. abiraterone acetate 1000 mg PO daily and prednisone 5 mg PO BID; 2. cabazitaxel 20 mg/m2 IV and carboplatin AUC 4 IV q3 weeks; 3. enzalutamide 160 mg PO daily and radium-223 50 kBq/kg IV q4 weeks (in those with bone metastases). After completion of this 9 month regimen, patients are followed on ADT alone. Primary endpoint is PSA or radiographic time to disease progression. Results: From 3/2017 to 10/2018, 28 of 40 planned men with mCRPC were enrolled, 19 (67.9%) with bone metastases. PSA response rates ( > 90%/ > 50%), compared to baseline, following each treatment module: 1. 50%/78.6%; 2. 50%/92.7%; 3. 64.39%/92.7%. Currently, 14 patients have completed the study regimen with median follow up of 3.6 months, 8 of whom continue without any additional therapy. Of the patients evaluable for primary endpoint, median time to PSA progression is 96+ days (95% CI 82-110+ days). The regiment was well tolerated, grade 3/4 adverse effects include: hyperglycemia (17.9%), diarrhea (7.1%), anemia (3.6%), fatigue (3.6%), neutropenia (3.6%), thrombocytopenia (3.6%). Measurable response and molecular correlate data will be presented. Conclusions: Treatment of mCRPC with a rapidly-cycling non-cross reactive regimen is feasible, demonstrates significant antitumor benefits, and is well tolerated. Further follow up will determine if PRINT delays progression compared with standard approaches. Clinical trial information: NCT02903160.

A retrospective analysis of treatment patterns in metastatic castration-resistant prostate cancer patients treated with radium-223

180

Background: Radium-223 (RA-223) is the first FDA approved targeted alpha therapy that significantly improves overall survival (OS) in patients (pts) with metastatic castration resistant prostate cancer (mCRPC) with symptomatic bone metastases. There is limited real world data describing RA-223 current use. Methods: A retrospective patient chart review was done of men who received at least 1 cycle of Ra-223 for mCRPC in 10 centers throughout the US (4 academic, 6 private practices). All pts had a minimum follow-up of 4 months, or placed in hospice or death. Descriptive analyses for clinical characteristics and treatment outcomes were performed. Results: Among the 200 pts (mean age-73.6 years, mean Charlson comorbidity index-6.9) RA-223 was initiated on average 1.6 years from mCRPC diagnosis (first line use (1L)=38.5%, 2L=31.5% and ≥3L=30%). 78% completed 5-6 cycles of RA-223 with mean therapy duration of 4.2 months. Among all pts, 43% received RA-223 as monotherapy (no overlap with other mCRPC therapies) while 57% had combination therapy with either abiraterone or enzalutamide. Median OS following RA-223 initiation was 21.2 months (95% CI 19.6- 29.2). Table provides the RA-223 utilization by type of clinical practice. Conclusions: Utilization of RA-223 in this real world data set was distinct from clinical trial data. Most patients received RA-223 in combination with abiraterone or enzalutamide, therapies that were unavailable when the pilot trial was conducted. Median survival was 21.2 months. Real world use of RA-223 has evolved as newer agents have become FDA approved in bone-metastatic CRPC. Academic and community patterns of practice were more similar than distinct. [Table: see text]

Evolving patterns of metastatic renal cell carcinoma: A meta-analysis

563

Background: Advances in diagnostic and treatment modalities have resulted in better outcomes in metastatic renal cell carcinoma (mRCC) patients. With new therapies extending survival, we hypothesize that pattern of metastatic disease has evolved over time. We assessed the pattern of metastases as reported in baseline characteristics of prospective clinical trial patients between 1990 and 2018. Methods: This study identified all phase I-III mRCC therapeutic clinical trials published between January 1990 and July 2018 in PubMed and ClinicalTrials.gov. Studies that included patients with other cancers or did not report metastases were excluded. Data was stratified to examine differences in three listed treatment eras for first-line therapy. Linear regression models were used to evaluate temporal trends and subcategorized as either First Line Only treatments (FLO) or Second-Line and Beyond (SLB). Results: 127 clinical trials encompassing 16534 subjects were identified. Between 1990 and 2018, rates of lymph node metastases in the FLO population increased significantly at 1.03% per year ( P < 0.05). The rate of lung and liver metastases in FLO showed a trend of increase at 0.48% and 0.04% per year, respectively, but decreased -0.73% and -0.15% per year in the SLB population. Moreover, rate of bone metastasis showed a trend of increase in both populations, particularly between the VEGF/TKI and Immunotherapy/TKI eras in the SLB population (18.89% to 29.19%). Conclusions: Notable changes were found in the pattern of metastasis in patients with mRCC. Increasing rate of bone metastasis may warrant dedicated bone imaging for routine staging in patients with mRCC. These evolving patterns may have important implications in treatment selection and prognosis in this patient population. [Table: see text]

Characterization of PSA at death in patients with metastatic castration-resistant prostate cancer

184

Background: Prostate Specific Antigen (PSA) is a valuable prognostic and predictive biomarker in prostate cancer (PC). Currently, the significance of PSA at death is undefined. In this single institution retrospective study, we aim to characterize the significance of PSA at death in patients with metastatic castration-resistant prostate cancer (mCRPC). Methods: Using the Mount Sinai Genitourinary (GU) Cancer Biorepository, an IRB approved database containing all consented GU cancer patients seen between 2010-2018, we stratified patients into the following cohorts based on their PSA at death: < 10, 10-100, 100-1000, and > 1000 ng/ml. We excluded data of patients who had less than 3 visits to the Mount Sinai Hospital. A descriptive analysis was performed to assess clinical characteristics of disease, treatment response, and outcomes. Results: We identified 1097 PC patients, and 101 were found to be deceased following a diagnosis of mCRPC. Cohorts of higher PSA level at death were associated with: a lower Gleason score at diagnosis, a longer time to castration resistance, higher burden of metastatic disease at death (non-visceral and visceral), and longer OS in patients with mCRPC (see table). Conclusions: In this study, PSA at death is associated with several important clinical characteristics and outcome, including overall survival. These differences may be attributed to their underlying biologic behavior. These results are hypothesis generating, and larger studies will be needed to further assess the significance of these findings. [Table: see text]

Patients with an extremely high prostate-specific antigen at prostate cancer diagnosis: A single institution analysis

309

Background: High prostate specific antigen (PSA) at diagnosis is associated with worse outcomes in patients (pt) with prostate cancer. However, treatment selection and clinical outcome in those diagnosed with an extremely high PSA (> 500 ng/ml) are not well characterized, and we aim to better study this unique pt population. Methods: Using the Mount Sinai Genitourinary (GU) Cancer Biorepository, an IRB approved database containing all consented GU cancer pts seen between 2010-2018, we identified 23 pts with a PSA >500 at prostate cancer diagnosis. Descriptive analysis was performed to capture clinical characteristics, treatment selection and response, and outcomes in this cohort. Results: The median age and PSA at diagnosis were 64 (54-85) and 1057 ng/ml (528-11,418). At presentation, 1 pt had localized versus 22 pts had metastatic disease, 3 were asymptomatic, and sites of metastasis included lymph nodes (LN) only (n=3), bone only (n=8), or LNs and bone (n=11). Pts were initiated on either first line androgen deprivation (ADT) or ADT plus docetaxel if seen after 2015 (1 refused). All pts had >90% PSA response to first line therapy, with median PSA nadir 4.38 ng/ml (0.06-153), duration of response 6 months (1-33), and time to castration-resistant prostate cancer (CRPC) 14.5 months (5-99). There are differences in treatment selection and outcomes for pts treated with ADT vs. ADT plus docetaxel first line (see table). Conclusions: In pts with PSA >500 at prostate cancer diagnosis, we have observed significant heterogeneity in clinical presentation and response to treatment. In pts treated with first line ADT plus docetaxel, we observed 2 of 7 pts with extended treatment response (> 42 months). Differences in disease biology may account for this observation, and molecular characterization will be needed to better understand this subset. [Table: see text]

Effect of concurrent beta-blocker (BB) use in patients receiving immune checkpoint inhibitors for metastatic urothelial (mUC) and renal cell carcinomas (mRCC)

467

Background: Stress-induced adrenergic signaling suppresses the immune system. A pre-clinical mouse model has shown that pharmacologic beta-blockade can stimulate CD8+ T-cell activity, and as a result improve efficacy of checkpoint inhibitors (CPI) to inhibit growth in solid tumors. Herein, we investigate the effect of BB on outcomes of patients receiving immunotherapy in mUC and mRCC. Methods: Using the Mount Sinai Genitourinary (GU) Cancer Biorepository, an IRB approved database containing all consented GU cancer patients seen between 2010-2018, we identified patients with either UC or RCC that have received CTLA-4 and/or PD-1/PD-L1 blockade. Patients who received only 1 dose of CPI were excluded from this analysis. A descriptive analysis was performed to assess clinical characteristics and treatment response. Overall Survival (OS) was calculated with Kaplan-Meier curves and cox proportional hazard models. Results: We identified 34 evaluable patients with mUC and 14 with mRCC that received CPI (Table). The median age at initiation was 69 years (39–91 years) and 81.2% (39/48) received prior chemotherapy and/or molecular targeted therapies. The mean duration of therapy was longer in the BB group compared to non-BB group (10.6 vs. 4.0 mo). For patients with mUC, the overall response rate (ORR) was 62.5% vs. 12.5% in favor of the BB group. For the patients with mRCC, the ORR was 40.0% vs. 10.0% in favor of the BB group. There were more outstanding responders (>1 year) in the BB group when compared with the non-BB group (41.2% vs. 6.5%). Patients with BB use had significantly improved median OS (NR vs. 11.6 mo, p = 0.004) when compared to those who did not receive BB. Conclusions: In this single-center cohort, the concurrent use of BB receiving CPI therapy is associated with an improved ORR, duration of therapy, and OS. Although this is hypothesis generating, the addition of BB is a promising strategy to improve response of immunotherapy, and prospective validation of this approach will be needed. [Table: see text]

Characterization of sick visits at an enhanced oncology urgent care center

285

Background: The Oncology Care Unit (OCU) is an urgent care center open during after-hours and weekends for patients with cancer and blood disorders at the Mount Sinai Hospital. This 6-bed, nurse practitioner-run unit aims to decrease the need for emergency room (ER) visits and hospitalization in this high risk patient population. Herein we characterize utilization of this unit for urgent clinical management (“sick visits”). Methods: We identified all patients treated in the OCU between 5/12/17 and 4/8/18, and collected information on diagnosis, treatment, and utilization of the ER or hospitalization. We used descriptive statistics to identify characteristics of those patients treated in the OCU. Results: Of the 1,934 visits to the OCU, 100 (5%) were coded as “sick visits”. Of this cohort, 39% had solid tumors, 44% liquid tumors, and 17% benign hematologic conditions. Among the oncology patients, the average number of prior treatment lines was 4.6 and average time since diagnosis was 51.3 months. Of all cancers, 84% were classified as advanced stage or high-risk. Treatments for the entire group included: transfusion (T, 20%), hydration (H, 20%), and infusion (I, 13%). Similarly, 39% of visits were for H+I, 3% for T+H, 4% for T+I, and 1% for T+H+I. 5% of patients had a repeat, unplanned OCU sick visit in the next 7 days. Among the sick visits, 28% resulted in hospitalization, with a 14-day average length of stay. Further results are shown in Table 1. Conclusions: The OCU provides enhanced diagnostic and therapeutic services for high-risk hematology/oncology patients. These services often exceed the capabilities of a busy practice and would otherwise prompt an ER visit and/or hospitalization. We now aim to study the effect of the OCU on ER utilization and admission rates as well as to analyze its cost effectiveness. [Table: see text]

Web-Based Tool to Facilitate Shared Decision Making With Regard to Neoadjuvant Chemotherapy Use in Muscle-Invasive Bladder Cancer

PURPOSE

Level 1 evidence supports the use of neoadjuvant chemotherapy (NAC) for the treatment of muscle-invasive bladder cancer (MIBC), but observational data demonstrate that this approach is underused. A barrier to shared decision making is difficulty in predicting and communicating survival estimates after cystectomy with or without NAC.

METHODS

We included patients with MIBC from the National Cancer Database treated with cystectomy. A state-transition model was constructed for calculating 5-year death risk using baseline patient-, tumor-, and facility-level variables. Internal-external cross-validation by geographic region was performed. The effect of NAC was integrated using a literature-derived hazard ratio. Bladder cancer-specific and other-cause mortality was estimated from all-cause mortality rates from US life tables. From the state-transition model, a Web-based tool was developed and pilot usability testing performed.

RESULTS

A total of 9,824 patients with MIBC who underwent cystectomy were eligible for inclusion. Median overall survival was 39.6 months (95% CI, 37.4 to 42.4 months). Increasing age, higher clinical T stage, higher comorbidity index, and black race were associated with shorter survival. Private insurance, higher income, and cystectomy at a high-volume facility were associated with longer survival. The prediction model was well calibrated across geographic regions, with observed-to-predicted 5-year death risks ranging from 0.85 to 1.17. Absolute risk reductions with NAC varied from 8.6% to 10.1%. The Web-based tool allowed input of the predictor variables and a user-defined hazard ratio associated with the effect of NAC to generate individualized survival estimates. The tool demonstrated good usability with clinicians.

CONCLUSION

A Web-based tool was developed to individualize outcome prediction and communication in patients with MIBC treated with cystectomy with or without NAC to facilitate shared decision making.

Randomized, Noncomparative, Phase II Trial of Early Switch From Docetaxel to Cabazitaxel or Vice Versa, With Integrated Biomarker Analysis, in Men With Chemotherapy-Naïve, Metastatic, Castration-Resistant Prostate Cancer

Purpose The TAXYNERGY trial ( ClinicalTrials.gov identifier: NCT01718353) evaluated clinical benefit from early taxane switch and circulating tumor cell (CTC) biomarkers to interrogate mechanisms of sensitivity or resistance to taxanes in men with chemotherapy-naïve, metastatic, castration-resistant prostate cancer. Patients and Methods Patients were randomly assigned 2:1 to docetaxel or cabazitaxel. Men who did not achieve ≥ 30% prostate-specific antigen (PSA) decline by cycle 4 (C4) switched taxane. The primary clinical endpoint was confirmed ≥ 50% PSA decline versus historical control (TAX327). The primary biomarker endpoint was analysis of post-treatment CTCs to confirm the hypothesis that clinical response was associated with taxane drug-target engagement, evidenced by decreased percent androgen receptor nuclear localization (%ARNL) and increased microtubule bundling. Results Sixty-three patients were randomly assigned to docetaxel (n = 41) or cabazitaxel (n = 22); 44.4% received prior potent androgen receptor-targeted therapy. Overall, 35 patients (55.6%) had confirmed ≥ 50% PSA responses, exceeding the historical control rate of 45.4% (TAX327). Of 61 treated patients, 33 (54.1%) had ≥ 30% PSA declines by C4 and did not switch taxane, 15 patients (24.6%) who did not achieve ≥ 30% PSA declines by C4 switched taxane, and 13 patients (21.3%) discontinued therapy before or at C4. Of patients switching taxane, 46.7% subsequently achieved ≥ 50% PSA decrease. In 26 CTC-evaluable patients, taxane-induced decrease in %ARNL (cycle 1 day 1 v cycle 1 day 8) was associated with a higher rate of ≥ 50% PSA decrease at C4 ( P = .009). Median composite progression-free survival was 9.1 months (95% CI, 4.9 to 11.7 months); median overall survival was not reached at 14 months. Common grade 3 or 4 adverse events included fatigue (13.1%) and febrile neutropenia (11.5%). Conclusion The early taxane switch strategy was associated with improved PSA response rates versus TAX327. Taxane-induced shifts in %ARNL may serve as an early biomarker of clinical benefit in patients treated with taxanes.

SM88 in non-metastatic rising PSA-recurrent prostate cancer

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Background: SM88 is a novel combination of substituted amino acid ( AA) and repurposed agents with non-toxic activity in a variety of cancers including prostate (PC). Non-metastatic biochemically recurrent PC (nmPC) is ideal for such a well-tolerated, non-androgen based treatment. We present biomarker activity including CTCs (circulating tumor cells) after completion of the Ib dose escalating pharmacokinetic portion of the SM88 development plan. Methods: Planned analysis of an ongoing prospective Phase Ib/II open label study of nmPC (PCWG3 definition). Subject 1 received the 1stdose level of AA, and others received 2x dose. All subjects also received a combination of low dose re-purposed CYP3a4 inducer, oxidative stress catalyst, and mTOR inhibitor. Results: Four subjects completed at least 1 cycle (28d) with all PK sampling as prespecified. Median age was 73(70-80); all had prior ADT that was discontinued 3-6 yrs earlier, and either had curative intent prostatectomy (n = 2) or RT (n = 2); Testosterone level was castrate in one after prior RT. CTCs fell (p < 0.01) to undetectable (n = 1) or by > 25% (n = 3) (see table) while PSA remained stable (PCWG3 criteria). Preliminary LDH, neutrophil/lymphocyte ratio (N:L), urinary NTx, bone specific AlkPhos (bAP) trends are in the table below. There were no drug related serious adverse events (2 grade: 1- pigmentation, 1- vasomotor). EORTC-QLQ30 and PR25 scores were either improved or stable. Conclusions: Treatment with SM88 in patients with nmPC in the completed phase Ib cohort was associated with CTC reduction, and stable biomarker trends including PSA and LDH. There was no significant toxicity or adverse patient reported outcomes. Based on these results, the dose escalation was stopped at the second level and a cohort expansion phase II initiated. A phase III RCT is planned for confirmation of these results. Clinical trial information: NCT02796898. [Table: see text]

Telemedicine-enabled clinical trial of metformin in patients (pts) with biochemically-recurrent prostate cancer (PCa)

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Background: Clinical trials are critical to informing cancer care but are hampered by slow accrual and suboptimal generalizability, both contributed to by poor geographic accessibility. We previously reported that > 50% of the US population resides > 1 hour from the nearest PCa clinical trial site (Galsky, JAMA Int Med, 2015). We sought to test the feasibility of replacing on-site study visits with telemedicine visits in a prospective clinical trial. Methods: Castration-naïve non-metastatic pts with PCa and a rising PSA after local therapy were eligible. Pts required a single on-site visit for enrollment. Treatment consisted of metformin 850 mg QD x 1 month followed by 850 mg BID x 5 months. Telemedicine visits were conducted monthly using a HIPAA-compliant smartphone application. The primary objective was to determine feasibility defined as completion of all eligible telemedicine visits by > 2/3 enrolled pts; pts were ineligible for future telemedicine visits if treatment discontinued early for toxicity or disease progression. Secondary objectives included safety, % patients with ≤ 20% PSA rise at 6 months, quality of life, and patient satisfaction. Results: 15 pts were enrolled, median age 68 (range, 57, 83), one-way driving time 1.3 hours (range, 0.2-2.8), Gleason score 7 (range, 6, 9), and pre-study PSA 4.1 (range, 0.52, 31.7). The 6 month course of metformin was completed by 11/15 (73%) pts; 2 discontinued early due to rising PSA, 1 due to adverse event (AE), and 1 remains on study. Excluding 1 pt still on study, 14/14 (100%; 95% CI 76, 100) pts completed all 78 eligible telemedicine visits. The most common AEs were diarrhea (grade 1 = 60%) and fatigue (grade 1 = 20%); 1 pt experienced grade ≥ 3 AE (dehydration). The 6-month PSA was ≤ 20% baseline in 1 pt; median % PSA change at last televisit was +52.8% (range, -3.0, +318.8). Quality of life and pt satisfaction will be reported at the meeting. Conclusions: To our knowledge, this is the first ever interventional oncology clinical trial conducted via telemedicine. Telemedicine-enabled trials are feasible and may overcome barriers to trial participation. Metformin was generally well tolerated but associated with minimal anti-PCa activity as measured by PSA. Clinical trial information: NCT02376166.