Efficacy of immune checkpoint inhibitors in alveolar soft-part sarcoma: results from a retrospective worldwide registry

BACKGROUND

Conventional cytotoxic drugs are not effective in alveolar soft-part sarcoma (ASPS). Immune checkpoint (programmed cell death protein 1/programmed death-ligand 1) inhibitors (ICIs) are promising drugs in ASPS. A worldwide registry explored the efficacy of ICI in ASPS.

MATERIALS AND METHODS

Data from adult patients diagnosed with ASPS and treated with ICI for advanced disease in expert sarcoma centers from Europe, Australia and North America were retrospectively collected, including demographics and data related to treatments and outcome.

RESULTS

Seventy-six ASPS patients, with a median age at diagnosis of 25 years (range 3-61 years), were registered. All patients received ICI for metastatic disease. Immunotherapy regimens consisted of monotherapy in 38 patients (50%) and combination in 38 (50%) (23 with a tyrosine kinase inhibitor). Among the 68 assessable patients, there were 3 complete responses and 34 partial responses, translating into an overall response rate of 54.4%. After a median follow-up of 36 months [95% confidence interval (CI) 32-40 months] since the start of immunotherapy, 45 (59%) patients have progressed on ICI, with a median progression-free survival (PFS) of 16.3 months (95% CI 8-25 months). Receiving ICI in first line (P = 0.042) and achieving an objective response (P = 0.043) correlated with a better PFS. Median estimated overall survival (OS) from ICI initiation has not been reached. The 12-month and 24-month OS rates were 94% and 81%, respectively.

CONCLUSIONS

This registry constitutes the largest available series of ASPS treated with ICI. Our results suggest that the ICI treatment provides long-lasting disease control and prolonged OS in patients with advanced ASPS, an ultra-rare entity with limited active therapeutic options.

A clinical evaluation of an ex vivo organ culture system to predict patient response to cancer therapy

Introduction

Ex vivo organ cultures (EVOC) were recently optimized to sustain cancer tissue for 5 days with its complete microenvironment. We examined the ability of an EVOC platform to predict patient response to cancer therapy.

Methods

A multicenter, prospective, single-arm observational trial. Samples were obtained from patients with newly diagnosed bladder cancer who underwent transurethral resection of bladder tumor and from core needle biopsies of patients with metastatic cancer. The tumors were cut into 250 μM slices and cultured within 24 h, then incubated for 96 h with vehicle or intended to treat drug. The cultures were then fixed and stained to analyze their morphology and cell viability. Each EVOC was given a score based on cell viability, level of damage, and Ki67 proliferation, and the scores were correlated with the patients' clinical response assessed by pathology or Response Evaluation Criteria in Solid Tumors (RECIST).

Results

The cancer tissue and microenvironment, including endothelial and immune cells, were preserved at high viability with continued cell division for 5 days, demonstrating active cell signaling dynamics. A total of 34 cancer samples were tested by the platform and were correlated with clinical results. A higher EVOC score was correlated with better clinical response. The EVOC system showed a predictive specificity of 77.7% (7/9, 95% CI 0.4-0.97) and a sensitivity of 96% (24/25, 95% CI 0.80-0.99).

Conclusion

EVOC cultured for 5 days showed high sensitivity and specificity for predicting clinical response to therapy among patients with muscle-invasive bladder cancer and other solid tumors.

Modified Citrus Pectin Treatment in Non-Metastatic Biochemically Relapsed Prostate Cancer: Long-Term Results of a Prospective Phase II Study

The optimal therapy for patients with non-metastatic biochemically relapsed prostate cancer (BRPC-M0) after local therapy is elusive. Thus, the evaluation of new non-toxic compounds in BRPC-M0 patients is warranted. PectaSol®-Modified citrus pectin (P-MCP) is a food supplement categorized as GRAS (Generally Recognized As Safe) by the FDA. It is a competitive inhibitor of the galectin-3 protein, which is involved in cancer pathogenesis. In an early report of the present phase 2 study, P-MCP treatment for 6 months led to prostate-specific antigen doubling time (PSADT) improvement in 75% of patients with BRPC-M0. Herein, we report the second long-term treatment phase of an additional 12 months of P-MCP therapy (4.8 g × 3/day orally) in patients without disease progression after the initial 6 months of therapy. Of the 46 patients that entered the second treatment phase, 7 patients withdrew consent and decided to continue therapy out of pocket, and 39 initiated the second treatment phase. After a total of 18 months of P-MCP treatment, 85% (n = 33) had a durable long-term response, with 62% (n = 24) showing decreased/stable PSA, 90% (n = 35) PSADT improvement, and all with negative scans. No patient had grade 3/4 toxicity. In conclusion, P-MCP may have long-term durable efficacy and is safe in BRPC-M0.

Pembrolizumab Plus Olaparib for Patients With Previously Treated and Biomarker-Unselected Metastatic Castration-Resistant Prostate Cancer: The Randomized, Open-Label, Phase III KEYLYNK-010 Trial

PURPOSE

There is an unmet need for therapeutic options that prolong survival for patients with heavily pretreated, metastatic castration-resistant prostate cancer (mCRPC). The phase III, open-label KEYLYNK-010 study evaluated pembrolizumab plus olaparib versus a next-generation hormonal agent (NHA) for biomarker-unselected, previously treated mCRPC.

METHODS

Eligible participants had mCRPC that progressed on or after abiraterone or enzalutamide (but not both) and docetaxel. Participants were randomly assigned (2:1) to pembrolizumab plus olaparib or NHA (abiraterone or enzalutamide). The dual primary end points were radiographic progression-free survival (rPFS) by blinded independent central review per Prostate Cancer Working Group-modified RECIST 1.1 and overall survival (OS). Time to first subsequent therapy (TFST) was a key secondary end point. Safety and objective response rate (ORR) were secondary end points.

RESULTS

Between May 30, 2019, and July 16, 2021, 529 participants were randomly assigned to pembrolizumab plus olaparib and 264 to NHA. At final rPFS analysis, median rPFS was 4.4 months (95% CI, 4.2 to 6.0) with pembrolizumab plus olaparib and 4.2 months (95% CI, 4.0 to 6.1) with NHA (hazard ratio [HR], 1.02 [95% CI, 0.82 to 1.25]; P = .55). At final OS analysis, median OS was 15.8 months (95% CI, 14.6 to 17.0) and 14.6 months (95% CI, 12.6 to 17.3), respectively (HR, 0.94 [95% CI, 0.77 to 1.14]; P = .26). At final TFST analysis, median TFST was 7.2 months (95% CI, 6.7 to 8.1) versus 5.7 months (95% CI, 5.0 to 7.1), respectively (HR, 0.86 [95% CI, 0.71 to 1.03]). ORR was higher with pembrolizumab plus olaparib versus NHA (16.8% v 5.9%). Grade ≥3 treatment-related adverse events occurred in 34.6% and 9.0% of participants, respectively.

CONCLUSION

Pembrolizumab plus olaparib did not significantly improve rPFS or OS versus NHA in participants with biomarker-unselected, heavily pretreated mCRPC. The study was stopped for futility. No new safety signals occurred.

Erdafitinib treatment in metastatic urothelial carcinoma: a real-world analysis

Background

Erdafitinib, a fibroblast growth factor receptor (FGFR) inhibitor is a standard post chemotherapy advanced treatment line for metastatic urothelial carcinoma harboring FGFR2/3 genomic alterations. It was approved based on a phase 2 clinical trial, revealing a 40% response rate, and 13.8 months overall survival. These FGFR genomic alterations are uncommon. Thus, real-world data on erdafitinb use is scant. We herein describe erdafitinib treatment outcome in a real world patient cohort.

Methods

We retrospectively reviewed the data of patients treated with erdafitinib from 9 Israeli medical centers.

Results

Twenty-five patients with metastatic urothelial carcinoma (median age 73, 64% male, 80% with visceral metastases) were treated with erdafitinib between January 2020 to October 2022. A clinical benefit (complete response 12%, partial response 32%, stable disease 12%) was seen in 56%. Median progression-free survival was 2.7 months, and median overall survival 6.73 months. Treatment related toxicity ≥ grade 3 occurred in 52%, and 32% discontinued therapy due to adverse events.

Conclusions

Erdafitinib therapy is associated with a clinical benefit in the real world setting, and associated with similar toxicity as reported in prospective clinical trials.

P-MCP treatment in non-metastatic biochemically relapsed prostate cancer (BRPC-M0): Final long-term results of a prospective phase II study

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Background: 30% of patients with localized PC will have a biochemical relapse post local therapy. Their optimal treatment remains elusive. While androgen deprivation therapy is effective in reducing PSA level, its long-term benefit remains undefined, and it is toxic. Thus, evaluation of new nontoxic compounds in these patients is warranted. PectaSol-C modified citrus pectin (P-MCP) is an inhibitor of galectin-3 protein, which is involved in prostate cancer pathogenesis. We herein report the final long-term results of a multi-center phase 2 study of P-MCP treatment in BRPC-M0. Methods: Patients with BRPC-M0 were enrolled and treated with P-MCP, 4.8 grams X 3/day, for 6 months (first phase of trial). Patients without PSA progression and/or with improvement of PSA doubling time (PSADT), and with negative scans, were treated for an additional 12 months (second phase of trial). Results: 59 patients were initially enrolled. After initial 6 months of therapy, 46 patients (78%) without disease progression entered the second phase of additional 12 months therapy. Among them, 7 patients withdrew consent and chose to continue therapy out of pocket. Of the remaining 39 patients, after another year of therapy (total of 18 months), 85% (n=33) had an overall long-term response, with a decreased/stable PSA (62 %, n=24), and improvement of PSADT (90 %, n=35), and with negative scans. No patient had grade 3/4 toxicity. Conclusions: P-MCP may have a durable long-term efficacy in patients with BRPC-M0. Clinical trial information: NCT01681823 .

Multinational Analysis of Estimated Health Care Costs Related to Extended-Interval Fixed Dosing of Checkpoint Inhibitors

IMPORTANCE

New dosing options for immune checkpoint inhibitors have recently been approved by the US Food and Drug Administration (FDA), including fixed dosing with extended intervals. Although the dose intensity appears the same, there is expected to be some waste with extended-interval dosing, as some drug remains in the bloodstream once a decision to stop treatment is made. The economic impact of extended-interval fixed dosing is unknown compared with standard-interval fixed dosing.

OBJECTIVE

To analyze the potential health care costs of using extended-interval fixed dosing instead of standard-interval fixed dosing.

DESIGN, SETTING, AND PARTICIPANTS

This economic evaluation used a pharmacoeconomic model to simulate 2 cohorts of patients with platinum-resistant metastatic urothelial cancer receiving pembrolizumab as second-line therapy at different dosing intervals using 2020 pricing data. Data were analyzed from 2020 to 2022.

EXPOSURES

The simulated patients received FDA-approved regimens of either 200 mg every 3 weeks or 400 mg every 6 weeks.

MAIN OUTCOMES AND MEASURES

The progression-free survival curve from the KEYNOTE-045 trial was used to estimate treatment duration. Drug, imaging, and administration costs were included in analyses. Sensitivity analyses were performed to assess how different imaging frequencies would affect the model results. The potential overall costs of using the 2 different dosing strategies were assessed. The base case was set in the US, while sensitivity analyses were set in several other countries.

RESULTS

In the base case analysis, dosing every 6 weeks instead of every 3 weeks resulted in an estimated 8.9% increase in pembrolizumab costs for the health care payer. Accounting for a decrease in infusion costs would result in an estimated net additional cost of $7483 per patient in the US (7.9% cost increase). In the US, this would amount to an increase of approximately $28 million annually for health care payers. Similar percentages in cost estimate increases were found for health care payers around the world, such as in Israel, where the net additional cost would be $5491 per patient.

CONCLUSIONS AND RELEVANCE

This economic evaluation assessed and quantified the potential increased costs related to extended-interval fixed dosing of pembrolizumab. The model method could be applied to other diseases and other drugs for which there has been a movement toward extended-interval dosing. Results may differ in other diseases owing to differing disease courses and patient profiles.

FORT-1: Phase II/III Study of Rogaratinib Versus Chemotherapy in Patients With Locally Advanced or Metastatic Urothelial Carcinoma Selected Based on FGFR1/3 mRNA Expression

PURPOSE

Rogaratinib, an oral pan-fibroblast growth factor receptor (FGFR1-4) inhibitor, showed promising phase I efficacy and safety in patients with advanced urothelial carcinoma (UC) with FGFR1-3 mRNA overexpression. We assessed rogaratinib efficacy and safety versus chemotherapy in patients with FGFR mRNA-positive advanced/metastatic UC previously treated with platinum chemotherapy.

METHODS

FORT-1 (ClinicalTrials.gov identifier: NCT03410693) was a phase II/III, randomized, open-label trial. Patients with FGFR1/3 mRNA-positive locally advanced or metastatic UC with ≥ 1 prior platinum-containing regimen were randomly assigned (1:1) to rogaratinib (800 mg orally twice daily, 3-week cycles; n = 87) or chemotherapy (docetaxel 75 mg/m², paclitaxel 175 mg/m², or vinflunine 320 mg/m² intravenously once every 3 weeks; n = 88). The primary end point was overall survival, with objective response rate (ORR) analysis planned following phase II accrual. Because of comparable efficacy between treatments, enrollment was stopped before progression to phase III; a full interim analysis of phase II was completed.

RESULTS

ORRs were 20.7% (rogaratinib, 18/87; 95% CI, 12.7 to 30.7) and 19.3% (chemotherapy, 17/88; 95% CI, 11.7 to 29.1). Median overall survival was 8.3 months (95% CI, 6.5 to not estimable) and 9.8 months (95% CI, 6.8 to not estimable; hazard ratio, 1.11; 95% CI, 0.71 to 1.72; P = .67). Grade 3/4 events occurred in 37 (43.0%)/4 (4.7%) patients and 32 (39.0%)/15 (18.3%), respectively. No rogaratinib-related deaths occurred. Exploratory analysis of patients with FGFR3 DNA alterations showed ORRs of 52.4% (11/21; 95% CI, 29.8 to 74.3) for rogaratinib and 26.7% (4/15; 95% CI, 7.8 to 55.1) for chemotherapy.

CONCLUSION

To our knowledge, these are the first data to compare FGFR-directed therapy with chemotherapy in patients with FGFR-altered UC, showing comparable efficacy and manageable safety. Exploratory testing suggested FGFR3 DNA alterations in association with FGFR1/3 mRNA overexpression may be better predictors of rogaratinib response.

Neoadjuvant 177Lu-PSMA-I&T Radionuclide Treatment in Patients with High-risk Prostate Cancer Before Radical Prostatectomy: A Single-arm Phase 1 Trial

BACKGROUND

High-risk localized prostate cancer (HRLPC) has a substantial risk of disease progression despite local treatment. Neoadjuvant systemic therapy before definitive local therapy may improve oncological outcomes by targeting the primary tumor and micrometastatic disease.

OBJECTIVE

To evaluate whether a lutetium-177 prostate-specific membrane antigen radioligand (LuPSMA) can be safely administered to patients with HRLPC before robot-assisted radical prostatectomy (RARP) and to describe immediate oncological outcomes.

DESIGN, SETTING, AND PARTICIPANTS

This was an open-label, single-arm clinical trial. Patients with HRLPC and elevated radioligand uptake on PSMA positron emission tomography/computed tomography were enrolled. Two or three LuPSMA radioligand doses (7.4 GBq) were given at 2-wk intervals. RARP with lymph node dissection was performed 4 wk after the last LuPSMA dose.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The rate of surgical complications, operative parameters, changes in functional and quality-of-life measures, and immediate oncological outcomes (histological findings and biochemical response) were measured. Data were analyzed descriptively.

RESULTS AND LIMITATIONS

Fourteen patients participated (median age 67 yr). Prostate-specific antigen decreased by 17% (interquartile range [IQR] 9-50%) after two LuPSMA doses and 34% (IQR 11-60%) after three doses. Thirteen patients underwent RARP with no identifiable anatomical changes or intraoperative complications. Four patients (30%) had postoperative complications (pneumonia, pulmonary embolism, urinary leak with urinary tract infection). At 3 mo postoperatively, 12 patients (92%) required one pad or less. Final whole-mount pathology showed positive surgical margins (PSMs) in seven patients (53%) and downgrading to International Society of Urological Pathology grade group 3 in three patients (23%). Treatment-related effects included a clear vacuolated cytoplasm and pyknotic nuclei.

CONCLUSIONS

LuPSMA followed by RARP appears to be surgically safe. While oncological outcomes are pending, continence recovery seems to be unaffected by LuPSMA treatment.

PATIENT SUMMARY

We evaluated outcomes for patients with aggressive localized prostate cancer who received treatment with a radioactive agent before surgical removal of their prostate. This approach appears to be safe and feasible, but its therapeutic efficacy is still unknown.

Health-related quality of life (HRQoL) for patients with advanced/metastatic urothelial carcinoma (UC) enrolled in KEYNOTE-052 who are potentially platinum ineligible

4561

Background: Frontline cisplatin-based chemotherapy improves survival in patients (pts) with UC, but ̃50% are cisplatin-ineligible owing to poor performance status or comorbidity. The definition of platinum ineligibility is not standardized; hence, treatment decisions are almost solely made by clinical judgment. Pembrolizumab (pembro) showed antitumor activity and manageable toxicity as frontline therapy in 370 cisplatin-ineligible pts in the single arm, phase 2 KEYNOTE-052 trial (NCT02335424). We present effects of pembro on HRQoL of pts in KEYNOTE-052 who were potentially platinum ineligible in this exploratory analysis. Methods: Eligible pts for KEYNOTE-052 were adults with no prior systemic chemotherapy for advanced/metastatic UC, ECOG PS ≤2, and measurable disease per RECIST v1.1 by blinded independent central review. Pembro 200 mg IV was administered Q3W for up to 2 y. Clinical characteristics of frail pts (platinum ineligible) were identified by extensive review of real-world treatment patterns and relevant literature. Consequently, platinum ineligibility was defined as having an ECOG PS ≥2 plus ≥1 of the following: visceral disease, creatinine clearance < 60 mL/min, or age ≥80 y. HRQoL was assessed using the EORTC QLQ-C30 and EQ-5D-3L during the first 4 cycles, then every 2 cycles for 1 year or until treatment discontinuation (whichever occurred first), and at least 30 days after treatment discontinuation. Key end points were change from baseline per the QLQ-C30 global health status (GHS)/QoL score, QLQ-C30 physical functioning subscale, and EQ-5D visual analog scale (VAS). The minimum important difference (MID) was 10 for QLQ-C30 score change (improved: ≥10; stable: –10 to 10; deteriorated: –10 or less); MID for VAS score change was 7 (improved: ≥7; stable: –7 to 7; deteriorated: –7 or less). Results: Median age for 143 pts was 75 y (range, 34-91); 129 pts (90.2%) had visceral disease; 142 (99.3%) had ECOG PS 2; 1 had ECOG PS 3 (enrolled in error). Compliance rate for HRQoL questionnaires was 93.7% at baseline. At the prespecified analysis time of week 9, 77.6% of pts had improved (n = 51) or stable (n = 60) QLQ-C30 GHS/QoL scores, 64.3% had improved (n = 35) or stable (n = 57) QLQ-C30 physical functioning scores, and 62.2% had improved (n = 56) or stable (n = 33) EQ-5D VAS scores. These scores were stable throughout the HRQoL assessment period for pts who continued pembro. Conclusions: In this exploratory analysis, pembro maintained HRQoL for pts with advanced/metastatic UC in KEYNOTE-052 who were potentially platinum-ineligible per the above criteria. Together with the efficacy and safety data from KEYNOTE-052, these data suggest that pembro monotherapy is a valuable treatment option for select pts with advanced UC who are more senior and/or deemed medically frail. Clinical trial information: NCT02335424.

Efficacy and safety of erdafitinib in patients with locally advanced or metastatic urothelial carcinoma: long-term follow-up of a phase 2 study

BACKGROUND

Erdafitinib, a pan-fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitor, was shown to be clinically active and tolerable in patients with advanced urothelial carcinoma and prespecified FGFR alterations in the primary analysis of the BLC2001 study at median 11 months of follow-up. We aimed to assess the long-term efficacy and safety of the selected regimen of erdafitinib determined in the initial part of the study.

METHODS

The open-label, non-comparator, phase 2, BLC2001 study was done at 126 medical centres in 14 countries across Asia, Europe, and North America. Eligible patients were aged 18 years or older with locally advanced and unresectable or metastatic urothelial carcinoma, at least one prespecified FGFR alteration, an Eastern Cooperative Oncology Group performance status of 0-2, and progressive disease after receiving at least one systemic chemotherapy or within 12 months of neoadjuvant or adjuvant chemotherapy or were ineligible for cisplatin. The selected regimen determined in the initial part of the study was continuous once daily 8 mg/day oral erdafitinib in 28-day cycles, with provision for pharmacodynamically guided uptitration to 9 mg/day (8 mg/day UpT). The primary endpoint was investigator-assessed confirmed objective response rate according to Response Evaluation Criteria In Solid Tumors version 1.1. Efficacy and safety were analysed in all treated patients who received at least one dose of erdafitinib. This is the final analysis of this study. This study is registered with ClinicalTrials.gov, NCT02365597.

FINDINGS

Between May 25, 2015, and Aug 9, 2018, 2328 patients were screened, of whom 212 were enrolled and 101 were treated with the selected erdafitinib 8 mg/day UpT regimen. The data cutoff date for this analysis was Aug 9, 2019. Median efficacy follow-up was 24·0 months (IQR 22·7-26·6). The investigator-assessed objective response rate for patients treated with the selected erdafitinib regimen was 40 (40%; 95% CI 30-49) of 101 patients. The safety profile remained similar to that in the primary analysis, with no new safety signals reported with longer follow-up. Grade 3-4 treatment-emergent adverse events of any causality occurred in 72 (71%) of 101 patients. The most common grade 3-4 treatment-emergent adverse events of any cause were stomatitis (in 14 [14%] of 101 patients) and hyponatraemia (in 11 [11%]). There were no treatment-related deaths.

INTERPRETATION

With longer follow-up, treatment with the selected regimen of erdafitinib showed consistent activity and a manageable safety profile in patients with locally advanced or metastatic urothelial carcinoma and prespecified FGFR alterations.

FUNDING

Janssen Research & Development.

Modified Citrus Pectin Treatment in Non-Metastatic Biochemically Relapsed Prostate Cancer: Results of a Prospective Phase II Study

Optimal therapy of biochemically relapsed prostate cancer (BRPC) after local treatment is elusive. An established modified citrus pectin (PectaSol^®, P-MCP), a dietary polysaccharide, is an established antagonist of galectin-3, a carbohydrate-binding protein involved in cancer pathogenesis. Based on PSA dynamics, we report on the safety and the primary outcome analysis of a prospective phase II study of P-MCP in non-metastatic BRPC based. Sixty patients were enrolled, and one patient withdrew after a month. Patients (n = 59) were given P-MCP, 4.8 grams X 3/day, for six months. The primary endpoint was the rate without PSA progression and improved PSA doubling time (PSADT). Secondary endpoints were the rate without radiologic progression and toxicity. Patients that did not progress by PSA and radiologically at six months continued for an additional twelve months. After six months, 78% (n = 46) responded to therapy, with a decreased/stable PSA in 58% (n = 34), or improvement of PSADT in 75% (n = 44), and with negative scans, and entered the second twelve months treatment phase. Median PSADT improved significantly (p = 0.003). Disease progression during the first 6 months was noted in only 22% (n = 13), with PSA progression in 17% (n = 10), and PSA and radiologic progression in 5% (n = 3). No patients developed grade 3 or 4 toxicity.

Abstract CT209: A clinical trial of cResponse, a functional assay for cancer precision medicine

Precision cancer therapy has the potential to revolutionize treatment outcome. While genomic analysis has become central to cancer personalized medicine, recent studies have not shown that it drastically improves patient survival as compared to standard drug selection. Additionally, genomic mutations may suggest several treatment protocols without elucidating which approach will yield the best clinical response. Moreover, for many drugs no genetic predictive biomarkers are available. To advance cancer precision diagnostics, we have developed cResponse, a functional drug sensitivity platform to determine individualized patient treatment regimens. Fresh patient cancer samples are taken by biopsy or resection and sectioned into 300 uM slices which when cultured in the cResponse platform demonstrate similar architecture and tissue proliferation to those found in vivo. We show that cResponse is able to preserve human cancer tissue in 3D together with its microenvironment, including endothelial and immune cells, at a high viability (&gt;90%) with continued cell division for 7 days in over twenty types of solids tumors. Importantly, the high viability of the tissue over an extended period of time allows for a rapid genomic profiling to help prioritize drugs to be tested by cResponse, as well as the capacity to evaluate the effects of slow acting drugs such as targeted therapy. To validate the capacity of the cResponse platform to predict patient response to cancer treatment, forty two patients with different cancer types receiving diverse chemotherapeutic and targeted agents were recruited to the study and their tumors were tested using cResponse prior to initiation of treatment. Cancer types included bladder, pancreatic, lung, colorectal, breast and sarcoma. After five days of treatment ex-vivo, the samples were fixed and designated a viability score (ranging from 0 to 100) based on an algorithm composed of a panel of histological and morphological markers. The cResponse score was compared to the clinical response to treatment of 27 patients for which this data is already available. The results demonstrated that cResponse could predict the patient's response with a specificity of 82% (9/11) and a sensitivity of 93.75% (15/16) when compared to the patient's imaging results. In the future, the integration of this platform in directing anti-cancer treatment may lead to better response rate of cancer patients to therapy.

Citation Format: Seth Salpeter, Vered Bar, Sara Aharon, Luba Torovsky, Adi Zundelevich, Hamutal Shachar, Hagit Shapira, Nancy Gavert, Ravid Straussman, Shay Golan, Eli Rosenbaum, Talia Golan, Raanan Berger, Zohar Dotan, Dan Leibovici, Shani Breuer, Yakir Rotenberg, Aviad Zick, Ayala Hubert, Hovav Nechushtan, Guy Neev. A clinical trial of cResponse, a functional assay for cancer precision medicine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT209.

Imaging-based prostate cancer screening among BRCA mutation carriers-results from the first round of screening

BACKGROUND

Male-carriers of BRCA1/2 gene mutations have an increased risk of prostate cancer (PCa) with a more aggressive phenotype. Current screening-guidelines suggest the use of prostate-specific antigen (PSA) only among BRCA2 carriers. Female carriers have extensive guidelines that include imaging. Our objective was to test the prevalence of PCa among BRCA carriers and examine screening strategies, using PSA and multiparametric magnetic resonance imaging (mpMRI).

PATIENTS AND METHODS

We recruited men aged 40-70 years with BRCA1/2 germline mutations and no prior history of prostate biopsy. All men underwent an initial round of screening which included PSA, and prostate mpMRI. PSA was considered elevated using an age-stratified threshold of ≥1 ng/ml for 40-50 years of age, ≥2 ng/ml for 50-60 years of age, and 2.5 ng/ml for 60-70 years of age. Men with elevated PSA and/or suspicious lesion on mpMRI were offered a prostate biopsy. PSA levels, MRI findings, PCa incidence, and tumor characteristics were evaluated. Decision curve analysis was used to compare screening strategies.

RESULTS

We recruited 188 men (108 BRCA1, 80 BRCA2), mean age 54 years (9.8). One hundred and ten (57%) had either elevated age-stratified PSA (75; 40%), a suspicious MRI lesion (67; 36%), or both (32; 17%). Of these, 92 (85%) agreed to perform a prostate biopsy. Sixteen (8.5%) were diagnosed with PCa; 44% of the tumors were classified as intermediate- or high-risk disease. mpMRI-based screening missed only one of the cancers (6%), while age-stratified PSA would have missed five (31%). Decision curve analysis showed that mpMRI screening, regardless of PSA, had the highest net benefit for PCa diagnosis, especially among men younger than 55 years of age. We found no difference in the risk of PCa between BRCA1 and BRCA2 (8.3% versus 8.7%, P = 0.91). Ninety percent had a Jewish founder mutation, thus the results cannot be generalized to all ethnic groups.

CONCLUSIONS

PCa is prevalent among BRCA carriers. Age may affect screening strategy for PCa in this population. Young carriers could benefit from initial MRI screening. BRCA carriers aged older than 55 years should use PSA and be referred to mpMRI if elevated.

TRIAL REGISTRATION

ClinicalTrial.gov ID: NCT02053805.

Identification of Tumor Antigens in the HLA Peptidome of Patient-derived Xenograft Tumors in Mouse

Personalized cancer immunotherapy targeting patient-specific cancer/testis antigens (CTA) and neoantigens may benefit from large-scale tumor human leukocyte antigen (HLA) peptidome (immunopeptidome) analysis, which aims to accurately identify antigens presented by tumor cells. Although significant efforts have been invested in analyzing the HLA peptidomes of fresh tumors, it is often impossible to obtain sufficient volumes of tumor tissues for comprehensive HLA peptidome characterization. This work attempted to overcome some of these obstacles by using patient-derived xenograft tumors (PDX) in mice as the tissue sources for HLA peptidome analysis. PDX tumors provide a proxy for the expansion of the patient tumor by re-grafting them through several passages to immune-compromised mice. The HLA peptidomes of human biopsies were compared with those derived from PDX tumors. Larger HLA peptidomes were obtained from the significantly larger PDX tumors as compared with the patient biopsies. The HLA peptidomes of different PDX tumors derived from the same source tumor biopsy were very reproducible, even following subsequent passages to new naïve mice. Many CTA-derived HLA peptides were discovered, as well as several potential neoantigens/variant sequences. Taken together, the use of PDX tumors for HLA peptidome analysis serves as a highly expandable and stable source of reproducible and authentic peptidomes, opening up new opportunities for defining large HLA peptidomes when only small tumor biopsies are available. This approach provides a large source for tumor antigens identification, potentially useful for personalized immunotherapy.

Cardiac biomarkers in patients with prostate cancer and cardiovascular disease receiving gonadotrophin releasing hormone agonist vs antagonist

BACKGROUND

Gonadotrophin releasing hormone (GnRH) agonists and antagonists reduce testosterone levels for the treatment of advanced and metastatic prostate cancer. Androgen deprivation therapy (ADT) is associated with increased risk of cardiovascular (CV) events and CV disease (CVD), especially in patients with preexisting CVD treated with GnRH agonists. Here, we investigated the potential relationship between serum levels of the cardiac biomarkers N-terminal pro-B-type natriuretic peptide (NTproBNP), D-dimer, C-reactive protein (CRP), and high-sensitivity troponin (hsTn) and the risk of new CV events in prostate cancer patients with a history of CVD receiving a GnRH agonist or antagonist.

METHODS

Post-hoc analyses were performed of a phase II randomized study that prospectively assessed CV events in patients with prostate cancer and preexisting CVD, receiving GnRH agonist or antagonist. Cox proportional hazards models were used to determine whether the selected biomarkers had any predictive effect on CV events at baseline and across a 12-month treatment period.

RESULTS

Baseline and disease characteristics of the 80 patients who took part in the study were well balanced between treatment arms. Ischemic heart disease (66%) and myocardial infarction (37%) were the most common prior CVD and the majority (92%) of patients received CV medication. We found that high levels of NTproBNP (p = 0.008), and hsTn (p = 0.004) at baseline were associated with the development of new CV events in the GnRH agonist group but not in the antagonist. In addition, a nonsignificant trend was observed between higher levels of NTproBNP over time and the development of new CV events in the GnRH agonist group.

CONCLUSIONS

The use of cardiac biomarkers may be worthy of further study as tools in the prediction of CV risk in prostate cancer patients receiving ADT. Analysis was limited by the small sample size; larger studies are required to validate biomarker use to predict CV events among patients receiving ADT.

FORT-1: Phase II/III study of rogaratinib versus chemotherapy (CT) in patients (pts) with locally advanced or metastatic urothelial carcinoma (UC) selected based on FGFR1/3 mRNA expression

489

Background: Aberrant activation of fibroblast growth receptor (FGFR) signaling plays a role in UC. Rogaratinib, a pan-FGFR1-4 inhibitor, has promising efficacy and safety in pts with advanced muscle-invasive UC, selected based on FGFR1-3 mRNA overexpression and/or FGFR3-activating mutations/translocations. This Phase II/III, randomized, open-label study evaluated the efficacy of rogaratinib vs CT in pts with FGFR-positive advanced or metastatic UC who received prior platinum CT. We present an ORR analysis for rogaratinib vs CT. Methods: FGFR1/3 mRNA was tested by in situ hybridization of archival tissue. Pts were randomized 1:1 to 800 mg rogaratinib p.o. BID continuously or CT Q3W (i.v., docetaxel 75 mg/m2, paclitaxel 175 mg/m2, or vinflunine 320 mg/m2), and stratified by PIK3CA/ RAS-activating mutations, prior immunotherapy, and modified 4-factor Bellmunt risk score. Results: 87 pts were assigned to rogaratinib and 88 to CT. Overall, 82.9% were male, median age was 69.0 yrs (range: 36-89), 96.6% had stage IV disease, and 2.3% were stage IIIB. PIK3CA/ RAS-activating mutations were present in 11.4% of pts. ORRs of 19.5% and 19.3% (1-sided p=0.56) and disease control rates of 49.4% and 55.7% (p=0.84) were observed for rogaratinib and CT, respectively; median progression-free survival was 2.7 months (95% CI 1.6, 4.2) and 2.9 months (95% CI 2.6, 4.2). Grade 3-4 treatment-emergent adverse events occurred in 40/86 pts (47%) treated with rogaratinib and 46/82 pts (56%) with CT, most commonly anemia (3% vs 15%), neutropenia (1% vs 17%), asthenia (9% vs 1%), lipase increase (8% vs 2%), fatigue (2% vs 6%), and urinary tract infection (2% vs 6%). Exploratory analysis of pts with FGFR3 DNA alterations (4 spot mutations and fusions) showed ORRs of 52.4% with rogaratinib and 26.7% with CT. Conclusions: In pts with FGFR1/3 tumor mRNA-positive UC, rogaratinib had efficacy comparable with standard CT and an acceptable safety profile. Subgroup analysis suggests rogaratinib may be more active in pts with an FGFR3 DNA alteration. Sensitivity analysis of biomarker subgroups is ongoing. Clinical trial information: NCT03410693.

Re-treatment with radium-223: 2-year follow-up from an international, open-label, phase 1/2 study in patients with castration-resistant prostate cancer and bone metastases

BACKGROUND

Radium-223 dichloride (radium-223) is approved for patients with castration-resistant prostate cancer (CRPC), symptomatic bone metastases, and no visceral disease using a dosing regimen of 6 injections (55 kBq/kg intravenously; 1 injection every 4 weeks). Early results from international, open-label, phase 1/2 study NCT01934790 showed that re-treatment with radium-223 was well tolerated with favorable effects on disease progression. Here we report safety and efficacy findings from 2-year follow-up of the radium-223 re-treatment study.

METHODS

Patients with CRPC and bone metastases who completed 6 initial radium-223 injections with no disease progression in bone and later progressed were eligible for radium-223 re-treatment (up to 6 additional radium-223 injections), provided that hematologic parameters were adequate and chemotherapy had not been administered after the initial course of radium-223. Concomitant cytotoxic agents were not allowed during re-treatment but were allowed at the investigator's discretion during follow-up; other concomitant agents for prostate cancer (including abiraterone acetate or enzalutamide) were allowed at investigator's discretion. The primary objective was safety. Exploratory objectives included time to radiographic bone progression, radiographic progression-free survival (rPFS), time to total alkaline phosphatase (tALP), and prostate-specific antigen (PSA) progression, overall survival (OS), time to first symptomatic skeletal event (SSE), and SSE-free survival, all calculated from re-treatment start. Evaluation of safety and exploratory efficacy objectives included active 2-year follow-up. Safety results from active follow-up and updated efficacy are reported.

RESULTS

Overall, 44 patients were re-treated with radium-223; 29 (66%) completed all 6 injections, and 34 (77%) entered 2-year active follow-up, during which no new safety concerns and no serious drug-related adverse events were noted. rPFS events (progression or death) occurred in 19 (43%) of 44 patients; median rPFS was 9.9 months. Radiographic bone progression occurred in 5 (11%) of 44 patients. Median OS was 24.4 months. Median times to first SSE and SSE-free survival were 16.7 and 12.8 months, respectively. Median time to tALP progression was not reached; median time to PSA progression was 2.2 months.

CONCLUSIONS

Re-treatment with radium-223 in this selected patient population was well tolerated, led to minimal hematologic toxicity, and provided continued disease control in bone at 2-year follow-up.

Increased Incidence of Lung Cancer Among Patients With Superficial Transitional Cell Carcinoma: A Potential Risk Cohort for Lung Cancer Screening

BACKGROUND

Smoking is a major risk factor for lung cancer (LC) and transitional cell carcinoma of the bladder (TCC). Current recommendations for LC screening do not include TCC as a risk factor for determining screening eligibility. In this study we aimed to evaluate whether TCC patients constitute a population who might benefit from LC screening.

PATIENTS AND METHODS

The Surveillance, Epidemiology, and End Results 18 database was used to determine the incidence, standardized incidence ratio (SIR), and the average time to diagnosis of LC in patients with localized TCC of the bladder (American Joint Committee on Cancer, sixth edition, stages 0-1).

RESULTS

On the basis of 91,606 patients with localized TCC, The SIR for LC in men was 1.89 (95% confidence interval [CI], 1.8-1.97), significantly different from the risk for all solid tumors. The SIR for LC in women was 2.43 (95% CI, 2.22-2.65), significantly higher than for men. The 5-year incidence of LC was 3.2%, and the 10-year incidence was 5.94%. The average time to diagnosis of LC was 3.4 years, with >80% of LC cases occurring within 5 years of TCC diagnosis.

CONCLUSION

Patients with localized TCC have a higher incidence of LC than the general population. The risk is significantly increased among women compared with men. Considering this increased risk, patients with early stage TCC might stand to benefit from LC screening. Additional differences were noted between male and female TCC patients, which bear further study.

Cardiovascular morbidity in a randomized trial comparing GnRH-agonist and antagonist among patients with advanced prostate cancer

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Background: Androgen-deprivation therapy (ADT) used in prostate-cancer may increase risk of cardiovascular disease (CVD). Limited preclinical and retrospective clinical data suggest that use of gonadotrophin-releasing hormone (GnRH)-antagonist may be associated with lower risk of CVD compared to GnRH-agonist. Methods: We conducted a randomized open-label study comparing the one year incidence of major cardiovascular and cerebrovascular event (MACCE) in prostate-cancer patients with pre-existing CVD commencing on GnRH-agonists or antagonists. Patients were followed every 3 months for the development of MACCE defined as either death, myocardial infarction (MI), cerebrovascular event (CVA), or percutaneous-coronary intervention (PCI). Serum levels of N-terminal pro-B-type natriuretic peptide (NTproBNP) were analyzed at baseline, 3, 6 and 12-months. Results: Eighty patients were enrolled (41 randomized to GnRH-antagonist, 39 to GnRH-agonist). Patients in both arms had similar age, baseline cardiovascular and prostate-cancer characteristics. During follow-up 15 patients developed a new cardiovascular event. Of these, nine patients developed MACCE (two deaths, one MI, two CVAs, and four PCI). Twenty percent (n = 8) of patients randomized to GnRH-agonists had a MACCE compared to 3% (n = 1) randomized to antagonists (log-rank p = 0.013). The absolute risk reduction for MACCE at 12 months using GnRH-antagonist was 18% (95%CI 5-31). Baseline levels of NTproBNP predicted events (AUC = 0.73 95%CI 0.54-0.91 p = 0.03) and increased over time only among patients with CV events. Conclusions: This is the first prospective study to test cardiovascular outcome among prostate-cancer patients receiving ADT. We demonstrated that in patients with pre-existing CVD, GnRH-antagonists was associated with development of fewer cardiovascular events compared to GnRH-agonists. Clinical trial information: NCT02475057.

Genomic analysis of urothelial cancer and associations with treatment choice and outcome

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Background: The use of next generation sequencing (NGS) is in a constant rise, without clear evidence to its utility in guiding treatment choices in urologic malignancies. While platinum-based chemotherapy (chemo) is still the mainstay of treatment, anti-PD1/L1 antibodies (IO) and FGFR3 inhibitors are emerging therapeutic options. Here our aim was to retrospectively assess the utility of next-generation sequencing (NGS) in selecting advanced treatment lines and define the response rates (RR) to chemo and IO in a real-life cohort. Methods: Metastatic urothelial carcinoma (UC) patients (pts) receiving first-line chemo were included. Paraffin-embedded pathological samples were subjected to FoundationOne genomic analysis (Roche) and to PD-L1 IHC staining using the FDA-approved Ventana's companion diagnostic test. Reports were anonymized and analysis was performed using Excel (Microsoft Office). Response was defined as either a clinically or radiologically-significant improvement. Results: 60 pts were included in this analysis with a median age of 69, of which 87.7% were men and 70% were current or past-smokers. RR to first line chemo or IO was 66% (95% CI 50-82) and 33% (95% CI 12-64), respectively. RR to second-line IO was 14% ((95% CI 4-40). Median TMB was 10 Mut/Mb (range 1-62) with no difference between smokers and non-smokers. 31% pts had tumor PD-L1 staining of > 5% and 3.7% were MSI-high. 107 genes were altered across all pts. The median number of genomic alterations (mutations (muts), amplifications (amps), deletions (dels) and re-arrangements) was 7 (range 2-17). The most frequent were TERT promotor and TP53 mutations, occurring in in 39 (69.6%) and 30 (53.6%) pts, respectively. FGFR3 alterations were found in 9 (15%) pts (7 mut and 2 fusions), 12 pts (20%) had alterations in ERBB2/Her2 (6 amps, 3 muts, 3 equivocal amps), BRCA1 mutations were found in 6 (10%) pts, and TSC1 alterations were found in 6 (10%) pts (4 muts and 2 dels). Altogether, about 40% of patients had potentially actionable alterations; of these, to date, the treatment of 8 patients (13%) was consequently altered. The RR to IO was non-significantly higher in pts with TMB > 10 (29% VS 20%, p = 0.1) across all pts in this cohort. Conclusions: RR to first-line chemo is higher than to first-line IO, and the association between TMB and response to IO is still debatable in UC. NGS can yield potentially 'actionable' alterations in about 40% of UC pts, and can change the treatment paradigm in the third of them.

Effect of pectasol-c modified citrus pectin (P-MCP) treatment (tx) on PSA dynamics in non- metastatic biochemically relapsed prostate cancer (BRPC) patients (pts): Primary outcome analysis of a prospective phase II study

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Background: 30% of pts with localized PC will have a biochemical relapse post local tx. Their optimal tx remains elusive. While androgen deprivation therapy is effective in reducing PSA level, its long-term benefit remain undefined, and it is associated with significant toxicities. Thus, evaluation of new non-toxic compounds in this pt population is warranted. P-MCP is a competitive inhibitor of galectin-3, a carbohydrate-binding protein, known to be involved in cancer pathogenesis. Pre-clinical data suggest that P-MCP is active in PC, and in two previous smaller clinical trials in biochemically relapsed prostate cancer (BRPC) pts, a PSA response/stabilization rate of 57%-75% was noted. In the present study, we aimed to evaluate the safety and PSA dynamics of P-MCP tx in BRPC pts. Methods: non-castrate non-metastatic BRPC pts were enrolled in a prospective phase 2 study of oral P-MCP tx, at 4.8 grams X 3/day for 6 months (mos). Eligible pts had 3 consecutive rise of PSA, without any tx in the previous 3 mos, a normal level of serum testosterone, and negative scans. The primary outcome was the rate of pts without disease progression (DP) (clinically, biochemically with stabilization/decrease of PSA or improvement of PSA doubling time = PSADT, and radiologically) at 6 mos. A Sample size of ≥ 50 pts provided 85% power to assess a decrease in DP rate from 80% (natural history) to 40% (P-MCP tx) at 6 mos. Pts that did not progress at 6 mos, were treated for subsequent 12 mos (secondary outcome of long term effect). Herein we report the results of the primary outcome analysis. Results: 53 pts were enrolled. Median age was 74 years. Tx of the primary tumor consisted of surgery in 13% (n = 7), radiation in 60% (n = 32), and both in 26% (n = 14). No pt had tx related grade 3/4 toxicity. One pt withdrew his consent after 1 mos. At present, 46 pts completed 6 mos of tx, and were analyzed for the primary outcome. Among them, 20% (n = 9) had grade 1 toxicity (all gas and bloating ). The primary outcome was met in 76% (n = 35), that did not progress at 6 mos of tx. Of these, 59% (n = 27) had a stabilization/decrease of PSA, 70% (n = 32) had an improvement (increase) of PSADT, and all had no metastases on scans at 6 mos. DP at 6 mos was noted in 24% (n = 11: PSA only in 20%, n = 9; PSA and scans in 4%, n = 2). Full cohort data (additional 6 pts that will complete 6 mos of tx) will be available by June 2019. Conclusions: The present study suggests the safety and potential benefit of P-MCP tx on progression of BRPC. Clinical trial information: NCT01681823.

A Cost-Effectiveness Analysis of Nivolumab and Ipilimumab Versus Sunitinib in First-Line Intermediate- to Poor-Risk Advanced Renal Cell Carcinoma

BACKGROUND

The treatment paradigm of advanced renal cell carcinoma (RCC) has changed rapidly in recent years. In first-line treatment of intermediate- to poor-risk patients, the CheckMate 214 study demonstrated a significant survival advantage for nivolumab and ipilimumab versus sunitinib. The high cost of combined immune-modulating agents warrants an understanding of the combination's value by considering both efficacy and cost. The objective of this study was to estimate the cost-effectiveness of nivolumab and ipilimumab compared with sunitinib for first-line treatment of intermediate- to poor-risk advanced RCC from the U.S. payer perspective.

MATERIALS AND METHODS

A Markov model was developed to compare the costs and effectiveness of nivolumab and ipilimumab with those of sunitinib in the first-line treatment of intermediate- to poor-risk advanced RCC. Health outcomes were measured in life-years and quality-adjusted life-years (QALYs). Drug costs were based on Medicare reimbursement rates in 2017. We extrapolated survival beyond the trial closure using Weibull distribution. Model robustness was addressed in univariable and probabilistic sensitivity analyses.

RESULTS

The total mean cost per-patient of nivolumab and ipilimumab versus sunitinib was $292,308 and $169,287, respectfully. Nivolumab and ipilimumab generated a gain of 0.978 QALYs over sunitinib. The incremental cost-effectiveness ratio (ICER) for nivolumab and ipilimumab was $125,739/QALY versus sunitinib.

CONCLUSION

Our analysis established that the base case ICER in the model for nivolumab and ipilimumab versus sunitinib is below what some would consider the upper limit of the theoretical willingness-to-pay threshold in the U.S. ($150,000/QALY) and is thus estimated to be cost-effective.

IMPLICATIONS FOR PRACTICE

This article assessed the cost-effectiveness of nivolumab and ipilimumab versus sunitinib for treatment of patients with intermediate- to poor-risk metastatic kidney cancer, from the U.S. payer perspective. It would cost $125,739 to gain 1 quality-adjusted life-year with nivolumab and ipilimumab versus sunitinib in these patients.

Re-treatment with radium-223: first experience from an international, open-label, phase I/II study in patients with castration-resistant prostate cancer and bone metastases

Background

Six radium-223 injections at 4-week intervals is indicated for patients with castration-resistant prostate cancer and symptomatic bone metastases. However, patients usually develop disease progression after initial treatment. This prospective phase I/II study assessed re-treatment safety and efficacy of up to six additional radium-223 injections.

Patients and methods

Patients had castration-resistant prostate cancer and bone metastases and six initial radium-223 injections with no on-treatment bone progression; all had subsequent radiologic or clinical progression. Concomitant agents were allowed at investigator discretion, excluding chemotherapy and initiation of new abiraterone or enzalutamide. The primary endpoint was safety; additional exploratory endpoints included time to radiographic bone progression, time to total alkaline phosphatase and prostate-specific antigen progression, radiographic progression-free survival, overall survival, time to first symptomatic skeletal event (SSE), SSE-free survival, and time to pain progression.

Results

Among 44 patients, 29 (66%) received all six re-treatment injections. Median time from end of initial radium-223 treatment was 6 months. Forty-one (93%) reported ≥1 treatment-emergent adverse event. No grade 4–5 hematologic treatment-emergent adverse events occurred. Only one (2%) patient had radiographic bone progression; eight (18%) had radiographic soft tissue tumor progression (three lymph node and five visceral metastases). Median times to total alkaline phosphatase and prostate-specific antigen progression were not reached and 2.2 months, respectively. Median radiographic progression-free survival was 9.9 months (12.8-month maximum follow-up). Five (11%) patients died and eight (18%) experienced first SSEs. Median overall survival, time to first SSE, and SSE-free survival were not reached. Five (14%) of 36 evaluable patients (baseline worst pain score ≤7) had pain progression. After 2 years of follow-up, 28 (64%) patients died, and the median overall survival was 24.4 months.

Conclusions

Re-treatment with a second course of six radium-223 injections after disease progression is well tolerated, with minimal hematologic toxicity and low radiographic bone progression rates in this small study with limited follow-up. Favorable safety and early effects on disease progression indicate that radium-223 re-treatment is feasible and warrants further evaluation in larger prospective trials.

Cost-effectiveness of pembrolizumab in second-line advanced bladder cancer

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Background: Recently, immune-modulating drugs have been introduced to the second line setting of advanced bladder cancer. Pembrolizumab increases overall survival and is associated with less toxicity compared to chemotherapy in this setting based on the Keynote-045 study. The high cost of immunotherapy necessitates an assessment of its value by considering both efficacy and cost. The objective of this study is to estimate the cost-effectiveness of pembrolizumab for the second-line treatment of advanced bladder cancer from the perspective of payers in multiple countries. Methods: We developed a Markov model to compare the costs and effectiveness of pembrolizumab with those of chemotherapy in the second-line treatment of advanced bladder cancer. Health outcomes were measured in life-years (LYs) and quality-adjusted life-years (QALYs). Drug costs were acquired for the following countries: U.S., U.K., Canada and Australia. Model robustness was addressed in univariate and probabilistic sensitivity analyses. Results: Pembrolizumab generated a gain of 0.36 QALYs compared to chemotherapy. Our analysis established the following incremental cost-effectiveness ratios (ICERs) for pembrolizumab versus chemotherapy in second-line advanced bladder cancer treatment - U.S. $122,557/QALY, U.K. $91,995/QALY, Canada $93,648/QALY, and Australia $99,966/QALY. The willingness-to-pay (WTP) thresholds per QALY are considered to be around 100,000-150,000 US dollars for the U.S., 20,000-50,000 pounds for the U.K. [25,000-65,000 US $], 20,000-100,000 CAD for Canada [16,000-80,000 US $] and 40,000-75,000 AUD for Australia [32,000-60,000 US $]. Conclusions: Cost-effectiveness and WTP thresholds vary between countries. Compared to the other countries examined, U.S. drug prices were found to be highest, leading to the highest ICER. With standard willingness-to-pay thresholds, pembrolizumab may be considered cost-effective in the U.S., but not in the other countries examined.

Effect of pectasol-c modified citrus pectin (P-MCP) treatment (tx) on PSA dynamics in non-metastatic biochemically relapsed prostate cancer (BRPC) patients (pts): Results of a prospective phase II study

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Background: 30% of pts with localized PC will have a biochemical relapse post local tx. The optimal tx of these pts remains elusive. While androgen deprivation therapy is effective in reducing PSA level, its long-term benefit on survival remain undefined, and it is associated with significant cumulative toxicities.Thus, evaluation of new non-toxic compounds in this pt population is warranted. P-MCP is a competitive inhibitor of galectin-3, a carbohydrate-binding protein, which is known to be involved in cancer pathogenesis. Pre-clinical and clinical data suggest that P-MCP is active in PC. We aimed to evaluate the safety and PSA dynamics of tx with P-MCP in pts with BRPC. Methods: Pts with non-castrate non-metastatic BRPC were enrolled in a prospective phase 2 study of tx with oral P-MCP, at 4.8 grams X 3/day for 6 months (mos). Pts that did not progress clinically, biochemically (PSA), and radiologically, at 6 mos, were treated for subsequent 12 mos. Sample size provided 85% power to assess a decrease in PSA progression rate from 80% (natural history) to 40% (P-MCP tx) at 6 mos. Results: The study was initiated in June 2013. 35 pts were enrolled. Median age was 74 years. Treatment of the primary tumor consisted of surgery in 11% (n = 4), radiation in 69% (n = 24), and both in 20% (n = 7). No pt had tx related grade 3/4 toxicity. One patient withdrew his consent after 1 mos. Of the 34 pts analyzed, 18% (n = 6) had grade 1 toxicity. 62% (n = 21) had a stabilization/decrease of PSA, and negative scans, at 6 mos, and entered the second 12 mos tx phase. A stabilization or improvement (increase) of PSA doubling time was noted in 79% (n = 27) of pts. Disease progression at 6 mos was noted in 38% (n = 13: PSA only 29%, n = 10; PSA and scans 9%, n = 3). Conclusions: The present study suggests a potential benefit of P-MCP tx on progression of BRPC. P-MCP tx is safe. Clinical trial information: NCT01681823.

Efficacy of programmed death 1 (PD-1) and programmed death 1 ligand (PD-L1) inhibitors in patients with FGFR mutations and gene fusions: Results from a data analysis of an ongoing phase 2 study of erdafitinib (JNJ-42756493) in patients (pts) with advanced urothelial cancer (UC)

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Background: FGFR3 mutations appear to be enriched in luminal 1 UC, which have low expression of markers associated with an immune response, including CD8-T-effector gene expression levels. Objective response rate (ORR) to PD-1 and PD-L1 inhibitors in luminal 1 tumors appear lower (10-19%) than in infiltrated luminal 2 and basal 3 tumors (ORR 31-34%). This suggests FGFR3 mutations occur within a group of tumors less likely to benefit from immune checkpoint inhibition (ICI). Here we describe outcomes of a subgroup of pts with FGFR2/3 mutations and gene fusions, previously treated with PD-1/PD-L1 inhibitors and included in an ongoing erdafitinib phase 2 study. Methods: Patients who had received prior immunotherapy for advanced UC were selected from those enrolled on BLC2001, an ongoing phase 2, open-label study of the pan-FGFR inhibitor erdafitinib in subjects with advanced UC with specific FGFR2/3 gene alterations (NCT02365597). We explored investigator-reported clinical outcomes including ORR and median time to progression (TTP) of pts treated with ICI preceding erdafitinib therapy. Results: 28/203 pts had previously received anti PD-1 or anti PD-L1 treatment. In this subgroup, the median age was 67.0 y; 82% were male, 79% had an ECOG score ≤1, 36% had liver metastases, and 93% had ≥2 prior lines of systemic therapy. The response rate to anti PD-1/PD-L1 agents was 3.6% (95% CI, 0.1%-18.3%) with one partial response. Median TTP was 3.4 mo (range 2-15 mo; 95% CI, 2.3-4.9). Conclusions: In this post-hoc analysis, FGFR mutations and gene fusions seem to select for a group of pts less likely to respond to immune checkpoint inhibition. Although caution is needed due to the retrospective nature of the data, the presence of these alterations may reflect an unmet need with currently approved agents. This finding highlights the need for FGFR alteration testing and an effective FGFR-targeted therapy. Clinical trial information: NCT02365597.

Radium-223 retreatment in an international, open-label, phase 1/2 study in patients with castration-resistant prostate cancer and bone metastases: 2-year follow-up

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Background: Radium-223 (Ra-223) treatment (tx) is indicated for patients (pts) with castration-resistant prostate cancer (CRPC) and symptomatic bone metastases (mets) (6 × 55 kBq/kg IV injections [inj]; 1 inj q4wk). Early results of an international, open-label, phase 1/2 study (NCT01934790) showed that re-treating pts with Ra-223 was well tolerated with favorable effects on disease progression. Here we report safety and efficacy findings from a 2-year follow-up. Methods: Pts with CRPC and bone mets who completed 6 initial Ra-223 inj with no disease progression in bone and later progressed were eligible for Ra-223 re-tx (6 additional Ra-223 inj), provided that hematologic parameters were adequate. No concomitant cytotoxic agents were allowed; other concomitant agents (eg, abiraterone, enzalutamide) were allowed at investigator discretion. The primary objective was safety. Exploratory objectives were time to radiographic bone progression, radiographic progression-free survival (rPFS), overall survival (OS), time to first symptomatic skeletal event (SSE), and SSE-free survival, all calculated from re-tx start. Pts will be followed for safety up to 7 years after last Ra-223 dose; an active 2-year follow-up evaluated exploratory objectives. Safety results from the active follow-up period and updated efficacy are reported. Results: 44 pts were re-treated with Ra-223; 29 (66%) completed all 6 inj (median number inj = 6). 34 (77%) of 44 pts entered active follow-up, during which no new safety concerns were noted. One new primary malignancy was reported (basal cell carcinoma). There were no serious drug-related adverse events. 19 (43%) of 44 pts had an rPFS event (radiographic progression or death); median rPFS was 9.9 months. Only 5 (11%) of 44 pts had radiographic bone progression; median time to radiographic bone progression was not reached. Median OS was 24.4 months. Median time to first SSE and SSE-free survival were 16.7 and 12.8 months, respectively. Conclusions: Re-treating with Ra-223 was well tolerated in this select pt population, led to minimal hematologic toxicity, and provided continued disease control in bone at 2-year follow-up. Clinical trial information: NCT01934790.

Promoter methylation of MCAM, ERα and ERβ in serum of early stage prostate cancer patients

Background

Prostate cancer (PC) is the second most common cancer among men worldwide. Currently, the most common non-invasive approach for screening and risk assessment of PC is measuring the level of serum prostate-specific antigen (PSA). However, the sensitivity of PSA is 42.8 % and specificity is 41.1%. As a result, the serum PSA test leads to numerous unneeded biopsies. Therefore, a rigorous search for biomarkers for early detection of PC is ongoing. In this study, we aim to assess a panel of epigenetic markers in an intend to develop an early detection test for PC.

Results

The sensitivity and specificity of hypermethylation of MCAM was 66% and 73% respectively which is an improvement from the sensitivity and specificity of PSA. Considering a combination marker panel of MCAM, ERα and ERβ increased the sensitivity to 75% and the specificity became 70% for the minimally invasive early detection test of PC.

Materials and Methods

Sixteen primary matched tumor and serum were analyzed by quantitative methylation specific PCR (QMSP) to determine analytical and clinical sensitivity of the genes tested (SSBP2, MCAM, ERα, ERβ, APC, CCND2, MGMT, GSTP1, p16 and RARβ2). Additionally, serum samples from eighty four cases of PC, thirty controls and seven cases diagnosed as high grade Prostatic Intraepithelial Neoplasia (HGPIN) were analyzed.

Conclusions

Promoter methylation of MCAM, ERα and ERβ have a potential to be utilized as biomarker for the early detection of prostate PC as their sensitivity and specificity seem to be better than serum PSA in our cohort of samples. After robust validation in a larger prospective cohort, our findings may reduce the numbers of unwarranted prostate biopsies.

Cost Effectiveness of Nivolumab in Advanced Renal Cell Carcinoma

BACKGROUND

In recent years, new drugs have been introduced for second-line treatment of advanced renal cell carcinoma (RCC). Nivolumab increases overall survival and is associated with less toxicity compared to everolimus in this setting according to the CheckMate 025 study. However, because of the high cost of nivolumab, there is a need to define its value by considering both efficacy and cost.

OBJECTIVE

To estimate the cost effectiveness of nivolumab for second-line treatment of advanced RCC from the US payer perspective.

DESIGN, SETTING, AND PARTICIPANTS

A Markov model was developed to compare the costs and effectiveness of nivolumab with those of everolimus and placebo in second-line treatment of advanced RCC. Health outcomes were measured in life-years (LYs) and quality-adjusted LYs (QALYs). Drug costs were based on 2016 Medicare reimbursement rates.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Model robustness was assessed in univariable and probabilistic sensitivity analyses. We addressed the issue of the extensive duration of immunotherapy treatment among long-term survivors, which may or may not be approved by payers.

RESULTS AND LIMITATIONS

The total mean cost per patient was $101 070 for nivolumab and $50 935 for everolimus. Nivolumab generated a gain of 0.24 LYs (0.34 QALYs) compared to everolimus. The incremental cost-effectiveness ratio (ICER) for nivolumab was $146 532/QALY versus everolimus and $226 197/QALY versus placebo. Limiting the maximal treatment duration of nivolumab to 2 yr reduced the ICER to $121 788/QALY versus everolimus. The analysis is limited by data availability and our assumptions.

CONCLUSIONS

Our analysis established that with a willingness-to-pay threshold of $100 000 to $150 000 per QALY, nivolumab is estimated to be cost-effective versus everolimus, but not cost-effective versus placebo.

PATIENT SUMMARY

We assessed the cost effectiveness of nivolumab in previously treated metastatic kidney cancer. In the USA, it would cost $146 532 to gain one quality-adjusted life-year with nivolumab versus everolimus, or $226 197 versus placebo. Nivolumab is considered cost-effective versus everolimus, but not versus placebo.

Effect of PectaSol-C modified citrus pectin (P-MCP) treatment (tx) on PSA dynamics in patients (pts) with nonmetastatic, biochemically relapsed prostate cancer (BRPC): Results of the interim analysis of a prospective phase II study

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Background: 30% of pts with localized PC will have a biochemical relapse post local tx. The optimal tx of these pts remains elusive. While androgen deprivation therapy is effective in reducing PSA level, its long term benefit on survival remain undefined, and it is associated with significant cumulative toxicities.Thus evaluation of new non-toxic compounds in this pt population is warranted. P-MCP is a competitive inhibitor of galectin-3, a carbohydrate-binding protein, which is known to be involved in cancer pathogenesis. Preliminary pre-clinical and clinical data suggest that P-MCP is active in PC. We aimed to evaluate the safety and PSA dynamics of tx with P-MCP in pts with BRPC. Methods: Pts with non-castrate non metastatic BRPC were enrolled in a prospective phase 2 study of tx with oral P-MCP, at 4.8 grams X 3/day. Pts that did not progress clinically, biochemically (PSA), and radiologically, at 6 months (mos), were treated for subsequent 12 mos. Sample size provided 85% power to assess a decrease in PSA progression rate from 80% (natural history) to 40% (P-MCP tx) at 6 mos. We report here first results of a pre-planned interim analysis after ≤ 50% of planned enrolled pt completed 6 mos of tx. Results: The study was initiated in June 2013. We report here the 6 mos data of the first 35 pts enrolled. Median age was 74 years. Treatment of the primary tumor consisted of surgery in 11% (n = 4), radiation in 69% (n = 24), and both in 20% (n = 7). No pt had tx related grade 3/4 toxicity. One patient withdrew his consent after 1 mos. Of the 34 pts analysed, 18% (n = 6) had grade 1 toxicity. 62% (n = 21) had a stabilization/decrease of PSA, and negative scans, at 6 mo, and entered into the second 12 mos tx phase. A stabilization or improvement (increase) of PSA doubling time was noted in 79% (n = 27) of pts. Disease progression at 6 mos was noted in 38% (n = 13: PSA only 29%, n = 10; PSA and scans 9%, n = 3). A future final report will include full tx data (18 mos) and correlative analysis. Conclusions: The interim analysis of the present study suggests a potential benefit of P-MCP tx on progression of BRPC. P-MCP tx is safe. Final analysis is pending. Clinical trial information: NCT01681823.

Cost-effectiveness of nivolumab in advanced renal cell carcinoma

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Background: In recent years, new drugs have been introduced to the second line setting of advanced renal cell carcinoma (RCC). Nivolumab increases overall survival and is associated with less toxicity compared to everolimus in this setting based on the Checkmate 025 study. However, due to nivolumab's high cost there is a need to define its value by considering both efficacy and cost. The objective of this study was to estimate the cost-effectiveness of nivolumab for the second-line treatment of advanced RCC from the US payer perspective. Methods: A Markov model was developed to compare the costs and effectiveness of nivolumab with those of everolimus or placebo in the second-line treatment of advanced RCC. Health outcomes were measured in life-years and quality-adjusted life-years (QALYs). Drug costs were based on Medicare reimbursement rates in 2016. Model robustness was addressed in univariable and probabilistic sensitivity analyses. We addressed the controversial issue of the extensive duration of immunotherapy treatment amongst long term survivors, which may or may not be approved by payers. Results: The total mean cost per-patient of nivolumab versus everolimus was $101,070 and $50,935, respectfully. Nivolumab generated a gain of 0.24 LYs (0.34 QALYs) over everolimus and 0.89 LYs (0.96 QALYs) over placebo. The incremental cost-effectiveness ratio (ICER) for nivolumab was $146,532/QALY versus everolimus and $105,232/QALY versus placebo. Limiting the maximal treatment duration of nivolumab to two years lowered the ICER to $121,788/QALY versus everolimus and $96,418/QALY versus placebo. Conclusions: Our analysis established an ICER of $146,532/QALY for nivolumab versus everolimus in second-line advanced RCC treatment.