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.

Disease characteristics and outcome of patients (pts) with metastatic castration-resistant prostate cancer (mCRPC) who received a beta emitter (177Lu-PSMA) after an alpha emitter (radium-223)

e17592

Background: Ra-223, a targeted alpha therapy, showed an overall survival (OS) benefit and favorable safety profile in mCRPC pts in a phase 3 trial. 177Lu-PSMA radioligand is an investigational agent for mCRPC. REASSURE (NCT02141438) is a global, prospective, observational study investigating Ra-223 safety in routine clinical practice over 7 years’ follow-up in mCRPC pts. Data from the second prespecified interim analysis (IA) were used to investigate safety and outcomes of pts who received 177Lu-PSMA after Ra-223 therapy. Methods: Data cut-off for the second prespecified IA was March 2019, and included pts who had subsequent 177Lu-PSMA after the last Ra-223 dose. Disease characteristics, adverse events (AEs) after last Ra-223 dose, and OS are described. Results: Of 1465 pts overall, 26 received 177Lu-PSMA subsequent to Ra-223. In this subgroup, pts received multiple anticancer therapies prior to 177Lu-PSMA. 13 pts (50%) received Ra-223 as combination therapy at second line (metastatic setting). Pts received a median of six Ra-223 doses. After Ra-223 treatment ended, 3 pts (12%) had drug-related serious AEs, 9 pts (35%) had grade 3/4 bone marrow suppression-relevant hematologic AEs. Median duration of 177Lu-PSMA treatment was 3.5 months. 19 pts (73%) received 177Lu-PSMA as fourth-line therapy or onwards. OS was 28.0 months from start of Ra-223 and 13.2 months from start of 177Lu-PSMA. Conclusions: In this select population receiving a sequence of multiple lines of therapy with different modes of action, grade 3/4 hematologic AEs after Ra-223 were low. Treatment with subsequent 177Lu-PSMA seems feasible, based on duration of 177Lu-PSMA and survival. Clinical trial information: NCT02141438 . [Table: see text]

The association between allopurinol use and urologic malignancies: A nested case-control study

435

Background: Oxidative stress may be involved in tumorigenesis processes. Uric acid is an important natural antioxidant that may reduce oxidative stress. Allopurinol is a commonly used uric acid lowering agent. There are conflicting data regarding the association between allopurinol use and cancer incidence. In the present nested case control study, we aimed to evaluated the association between allopurinol use and urologic malignancies in a large western population. Methods: conducted a nested case-control study within a population-representative database from the United Kingdom (THIN). Study cases were defined as individuals with any diagnostic code of prostate cancer, bladder cancer, or renal cell carcinoma. For every case, four eligible controls were matched on age, gender, practice site, time of diagnosis, and duration of follow-up. Exposure of interest was any allopurinol use prior to cancer diagnosis. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for urologic malignancies were estimated using conditional logistic regression. Adjustment was performed for factors including smoking, BMI, and diabetes. Results: The study population included: for bladder cancer 13440 and 52421 matched controls, prostate cancer 27212 cases and 105940 controls, RCC 1547 cases and 6066 controls. Allopurinol use was associated with a significantly increase of risk for bladder cancer (adjusted OR 1.2, 95%CI 1.09-1.32, p<0.001). prostate cancer (adjusted OR 1.1, 95%CI 1.03-1.,17, p=0.003), RCC (adjusted OR 1.32, 95%CI 1-1..75, p=0.05). In a sensitivity analyses we observed similar associations when alopurinol use was initiated more than two years prior to cancer diagnosis, for bladder cancer (adjusted OR 1.2, 95%CI 1.08-1.33, p=0.001), prostate cancer (adjusted OR 1.09, 95%CI 1.02-1.16, p=0.01), RCC (adjusted OR 1.09, 95%CI 0.78-1.53, p=0.62). Conclusions: Allopurinol use may be associated with an increased risk for urologic malignancies.

Ramucirumab plus docetaxel versus placebo plus docetaxel in patients with locally advanced or metastatic urothelial carcinoma after platinum-based therapy (RANGE): overall survival and updated results of a randomised, double-blind, phase 3 trial

BACKGROUND

Ramucirumab-an IgG1 vascular endothelial growth factor receptor 2 antagonist-plus docetaxel was previously reported to improve progression-free survival in platinum-refractory, advanced urothelial carcinoma. Here, we report the secondary endpoint of overall survival results for the RANGE trial.

METHODS

We did a randomised, double-blind, phase 3 trial in patients with advanced or metastatic urothelial carcinoma who progressed during or after platinum-based chemotherapy. Patients were enrolled from 124 investigative sites (hospitals, clinics, and academic centres) in 23 countries. Previous treatment with one immune checkpoint inhibitor was permitted. Patients were randomly assigned (1:1) using an interactive web response system to receive intravenous ramucirumab 10 mg/kg or placebo 10 mg/kg volume equivalent followed by intravenous docetaxel 75 mg/m2 (60 mg/m2 in Korea, Taiwan, and Japan) on day 1 of a 21-day cycle. Treatment continued until disease progression, unacceptable toxicity, or other discontinuation criteria were met. Randomisation was stratified by geographical region, Eastern Cooperative Oncology Group performance status at baseline, and visceral metastasis. Progression-free survival (the primary endpoint) and overall survival (a key secondary endpoint) were assessed in the intention-to-treat population. The study is registered with ClinicalTrials.gov, NCT02426125; patient enrolment is complete and the last patient on treatment is being followed up for safety issues.

FINDINGS

Between July 20, 2015, and April 4, 2017, 530 patients were randomly allocated to ramucirumab plus docetaxel (n=263) or placebo plus docetaxel (n=267) and comprised the intention-to-treat population. At database lock (March 21, 2018) for the final overall survival analysis, median follow-up was 7·4 months (IQR 3·5-13·9). In our sensitivity analysis of investigator-assessed progression-free survival at the overall survival database lock, median progression-free survival remained significantly improved with ramucirumab compared with placebo (4·1 months [95% CI 3·3-4·8] vs 2·8 months [2·6-2·9]; HR 0·696 [95% CI 0·573-0·845]; p=0·0002). Median overall survival was 9·4 months (95% CI 7·9-11·4) in the ramucirumab group versus 7·9 months (7·0-9·3) in the placebo group (stratified HR 0·887 [95% CI 0·724-1·086]; p=0·25). Grade 3 or worse treatment-related treatment-emergent adverse events in 5% or more of patients and with an incidence more than 2% higher with ramucirumab than with placebo were febrile neutropenia (24 [9%] of 258 patients in the ramucirumab group vs 16 [6%] of 265 patients in the placebo group) and neutropenia (17 [7%] of 258 vs six [2%] of 265). Serious adverse events were similar between groups (112 [43%] of 258 patients in the ramucirumab group vs 107 [40%] of 265 patients in the placebo group). Adverse events related to study treatment and leading to death occurred in eight (3%) patients in the ramucirumab group versus five (2%) patients in the placebo group.

INTERPRETATION

Additional follow-up supports that ramucirumab plus docetaxel significantly improves progression-free survival, without a significant improvement in overall survival, for patients with platinum-refractory advanced urothelial carcinoma. Clinically meaningful benefit might be restricted in an unselected population.

FUNDING

Eli Lilly and Company.

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.

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

5015

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.

A phase Ib/II study of niraparib combination therapies for the treatment of metastatic castration-resistant prostate cancer (NCT03431350)

TPS5087

Background: Assessing multiple therapies in a single clinical trial can facilitate the rapid identification of new agents for the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC). Niraparib (Nirap) is a highly selective PARP inhibitor, with potent activity against PARP-1 and PARP-2 deoxyribonucleic acid (DNA)-repair polymerases. PARP inhibition may be especially lethal in tumor cells with genetic DNA damage response deficits (DRD). Based on promising preclinical and clinical data, this study is designed as a master protocol with nirap as a backbone therapy. Combination 1 assesses the safety and efficacy of nirap plus JNJ-63723283 (JNJ-283), an anti-PD-1 monoclonal antibody. Combination 2 assesses nirap plus abiraterone acetate and prednisone (AA-P). Methods: This multicenter, global, open-label study is currently open at 18 sites in 5 countries of the planned XX sites, and is enrolling patients with mCRPC who have progressed on ≥1 androgen-receptor targeted therapy for mCRPC. Enrollment at time of abstract submission was 25 for combination 1. When combined with AA-P, the RP2D has been determined to be nirap 200 mg. The recommended phase-2 dose (RP2D) of nirap plus JNJ-283 was determined in Part 1 based on the incidence of specified adverse events and PK data to be 480 mg every 4 weeks. For Part 2 of the study, patients are assigned to receive oral niraparib daily plus JNJ-283 infusions once every four weeks until disease progression, unacceptable toxicity, death, study termination. Part 2 is described in the table. Clinical trial information: NCT03431350. [Table: see text]

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

e16026

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

e16609

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.

Cannabis Impacts Tumor Response Rate to Nivolumab in Patients with Advanced Malignancies

BACKGROUND

There has been a significant increase in the use of immunotherapy and cannabis recently, two modalities that have immunomodulatory effects and may have possible interaction. We evaluated the influence of cannabis use during immunotherapy treatment on response rate (RR), progression-free survival (PFS), and overall survival (OS).

SUBJECTS, MATERIALS, AND METHODS

In this retrospective, observational study, data were collected from the files of patients treated with nivolumab in the years 2015-2016 at our hospital, and cannabis from six cannabis-supplying companies. Included were 140 patients (89 nivolumab alone, 51 nivolumab plus cannabis) with advanced melanoma, non-small cell lung cancer, and renal clear cell carcinoma. The groups were homogenous regarding demographic and disease characteristics. A comparison between the two arms was made.

RESULTS

In a multivariate model, cannabis was the only significant factor that reduced RR to immunotherapy (37.5% RR in nivolumab alone compared with 15.9% in the nivolumab-cannabis group (p = .016, odds ratio = 3.13, 95% confidence interval 1.24-8.1). Cannabis use was not a significant factor for PFS or OS. Factors affecting PFS and OS were smoking (adjusted hazard ratio [HR] = 2.41 and 2.41, respectively (and brain metastases (adjusted HR = 2.04 and 2.83, respectively). Low performance status (adjusted HR = 2.83) affected OS alone. Tetrahydrocannabinol and cannabidiol percentages did not affect RR in any group (p = .393 and .116, respectively).

CONCLUSION

In this retrospective analysis, the use of cannabis during immunotherapy treatment decreased RR, without affecting PFS or OS and without relation to cannabis composition. Considering the limitations of the study, further prospective clinical study is needed to investigate possible interaction.

IMPLICATIONS FOR PRACTICE

Although the data are retrospective and a relation to cannabis composition was not detected, this information can be critical for cannabis users and indicates that caution is required when starting immunotherapy.

Radium-223 in combination with paclitaxel in cancer patients with bone metastases: safety results from an open-label, multicenter phase Ib study

PURPOSE

Concomitant treatment with radium-223 and paclitaxel is a potential option for cancer patients with bone metastases; however, myelosuppression risk during coadministration is unknown. This phase Ib study in cancer patients with bone metastases evaluated the safety of radium-223 and paclitaxel.

METHODS

Eligible patients had solid tumor malignancies with ≥2 bone metastases and were candidates for paclitaxel. Treatment included seven paclitaxel cycles (90 mg/m² per week intravenously per local standard of care; 3 weeks on/1 week off) plus six radium-223 cycles (55 kBq/kg intravenously; one injection every 4 weeks, starting at paclitaxel cycle 2). The primary end point was percentage of patients with grade 3/4 neutropenia or thrombocytopenia during coadministration of radium-223 and paclitaxel (cycles 2, 3) versus paclitaxel alone (cycle 1).

RESULTS

Of 22 enrolled patients, 15 were treated (safety population), with 7 completing all six radium-223 cycles. Treated patients had primary cancers of breast (n = 7), prostate (n = 4), bladder (n = 1), non-small cell lung (n = 1), myxofibrosarcoma (n = 1), and neuroendocrine (n = 1). No patients discontinued treatment from toxicity of the combination. In the 13 patients who completed cycle 3, the rates of grade 3 neutropenia in cycles 2 and 3 were 31% and 8%, respectively, versus 23% in cycle 1; there were no cases of grade 4 neutropenia or grade 3/4 thrombocytopenia. Breast cancer subgroup safety results were similar to the overall safety population.

CONCLUSION

Radium-223 was tolerated when combined with weekly paclitaxel, with no clinically relevant additive toxicities. This combination should be explored further in patients with bone metastases.

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.

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

14

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.

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

178

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.

Abstract P1-16-03: An open-label, multicenter phase 1b trial of radium-223 + paclitaxel in cancer patients with bone metastases: Safety results from the breast cancer patient subgroup

Background: Taxanes have an established role in treating breast cancer (BC), and combination with radium-223 (Ra-223) may be an option in patients (pts) with bone metastases. Both therapies impact hematologic parameters, but myelosuppression risk in combination is unknown. A phase 1b trial (NCT02442063) in cancer pts with bone metastases studied Ra-223+paclitaxel (PTX) safety and mode of interaction regarding myelosuppression; BC subgroup safety results are presented.

Methods: Eligible pts had a malignant solid tumor with ≥2 bone metastases and were PTX candidates. Treatment (tx) was 7 PTX cycles (90 mg/m2/wk IV per local standard of care, 3 wk on/1wk off) + 6 Ra-223 cycles (55 kBq/kg IV; 1 injection q4wk, starting at PTX cycle 2). Primary endpoint was % pts with neutropenia and thrombocytopenia during Ra-223+PTX (cycles 2, 3) vs PTX alone (cycle 1). A dose-exposure-response model describing time course of Ra-223+PTX–induced suppression of absolute neutrophil counts was used to evaluate Ra-223+PTX mode of interaction (additive or synergistic) in the total population.

Results: 15/22 enrolled pts were treated (total population); 7 had BC (BC subgroup). Baseline characteristics of the 2 groups were similar; ECOG PS was better in BC pts (Table). Fewer BC pts had prior taxane therapy (29% vs 53%), but rates of ≥3 prior chemotherapy regimens were similar (43% vs 47%). BC pts, vs total population, had slightly longer median tx duration for Ra-223 (6 vs 5.5 cycles) and PTX (7 vs 6 cycles), and more pts who completed 6 Ra-223 doses (57% vs 47%). Tx discontinuation related to disease progression in 29% of BC pts vs 33% in total population. Table shows TEAEs. In the BC subgroup, all 7 pts completed cycle 3 and Gr 3 neutropenia rates were 43% in cycle 2 and 14% in cycle 3, vs 29% in cycle 1; there was no Gr 4 neutropenia or Gr 3/4 thrombocytopenia. In the total population, 13 pts completing cycle 3 were in the pharmacodynamics analysis. Their Gr 3 neutropenia rates were 31% in cycle 2 and 8% in cycle 3, vs 23% in cycle 1; there was no Gr 4 neutropenia or Gr 3/4 thrombocytopenia. Myelosuppression model for the total population showed an additive effect of Ra-223 to PTX-induced neutropenia, with an additional 10% average decrease in absolute neutrophil count vs PTX alone. BC subgroup modeling was not feasible due to small sample size.

 Total Population n=15BC Subgroup n=7Median age (range), y61(45-76)58(45-68)Tumor type, n (%)  Breast7(47)7(100)Prostate4(27)0Bladder1(7)0Non-small cell lung1(7)0Other2(13)0ECOG score, n (%)  06(40)5(71)18(53)1(14)Prior taxane therapy, n (%)8(53)2(29)≥3 prior chemotherapy regimens, n (%)7(47)3(43)TEAEs, n (%)  Gr 3/49(60)2(29)Serious6(40)2(29)Gr 3/4 TEAEs, n (%)*  Neutrophil count decreased6(40)3(43)White blood cell count decreased4(27)2(29) TEAE=treatment-emergent adverse event.*In &gt;15% of patients.

Conclusions: Ra-223 was well tolerated when combined with PTX in pts with solid tumors and bone metastases. The BC subgroup vs total population had slightly higher hematologic AE rates, but fewer Gr 3/4 and serious TEAEs; more BC pts also completed study tx. The combination should be explored further in pts with bone metastases.

Citation Format: Danson SJ, Perets R, Lopez J, Joensuu H, Peer A, Harris SJ, Souza F, Ploeger B, Pereira KMC, Geva R. An open-label, multicenter phase 1b trial of radium-223 + paclitaxel in cancer patients with bone metastases: Safety results from the breast cancer patient subgroup [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-16-03.

Abstract P4-02-02: Contrast-enhanced MRI does not accurately predict pathologic complete response (pCR) after neoadjuvant chemotherapy in early or locally advanced breast cancer

Background: Patients with early or locally advanced breast cancer achieving a pathologic complete response (pCR) after neoadjuvant chemotherapy have a lower risk for recurrence or death compared to patients with residual invasive cancer. In the future, breast surgery might be avoided in patients in whom the presence of residual tumor after neoadjuvant therapy can be ruled out with very high confidence. Magnetic resonance imaging (MRI) has been shown to be the most accurate radiologic tool in breast cancer diagnostics and follow-up care. Therefore, we investigated the diagnostic accuracy of contrast-enhanced MRI to predict a pathological complete remission after neoadjuvant chemotherapy.

Methods: This retrospective study included all non-metastatic breast cancer patients treated with neoadjuvant chemotherapy followed by a contrast-enhanced MRI and breast cancer surgery at our institution between 09/2006 and 05/2016. Three specialized breast radiologists, blinded to the clinical and pathological data, reevaluated all preoperative MRI scans and recorded the presence or absence of contrast enhancement as indicator for residual cancer. pCR was defined as no invasive tumor in breast and axilla (ypT0/is N0), however 3 alternative definitions were investigated as well (ypT0 N0, ypT0/is and ypT). Cross tables were used to calculate sensitivity, specificity, pCR-predictive value (PPV), non-pCR-predictive value (NPV) and accuracy. P-values reflecting PPV and NPV differences between various patient subgroups were calculated with Fisher's exact test. The Kaplan-Meier method was used for estimates of distant-recurrence-free survival (DRFS) and overall survival (OS).

Results: In total, 246 patients fulfilled the inclusion criteria and were evaluated. Overall pCR and radiologic complete remission (rCR) rate were 29% and 45%, respectively. Only 48% of rCR corresponded to a pCR (PPV). Conversely, in 87% of cases, residual tumor in the MRI was pathologically confirmed (NPV). The sensitivity to detect a pCR was 75%, while specificity and accuracy were 67% and 69%, respectively. The diagnostic performance of MRI to predict treatment response varied between different histologic and molecular tumor subtypes, however there were little differences between the 4 pCR definitions. The PPV was significantly lower in the hormone-receptor(HR)-positive subgroup compared with the HR-negative subgroup (33% vs. 61%; P = 0.004), especially in luminal-A-like (7%) and lobular carcinomas (0%), respectively. Despite the low concordance (Kohens kappa -0.1), the prognostic value for distant recurrence-free survival was similar between rCR (HR 0.29) and pCR (HR 0.27), respectively. The median pathologic tumor size of residual disease in false-positive cases (rCR but no pCR) was 0.7 cm (SD 0.98 cm).

Conclusion: Contrast-enhanced MRI does not accurately predict pCR after neoadjuvant chemotherapy in early or locally advanced breast cancer, especially in HR-positive tumors. However, in case of false rCR the dimension of residual disease is generally small. Since residual tumor tissue can be detected with high precision, preoperative breast MRI is still of value for operation planning.

Citation Format: Gampenrieder SP, Peer A, Weismann C, Meissnitzer M, Rinnerthaler G, Webhofer J, Westphal T, Popovscaia M, Meissnitzer T, Reitsamer R, Hauser-Kronberger C, Egger H, Hergan K, Mlineritsch B, Greil R. Contrast-enhanced MRI does not accurately predict pathologic complete response (pCR) after neoadjuvant chemotherapy in early or locally advanced breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-02-02.

Treatment of Patients Aged over 50 Years with Non-Osseous Ewing's Sarcoma Family Tumors: Five Cases and Review of Literature

Background

Most clinical trials on Ewing's sarcoma family of tumors include pediatric and adolescent populations, whereas clinical data on older patients are limited.

Patients and Methods

We report on 5 patients older than 50 years with a tumor of the Ewing's sarcoma family treated recently in our department.

Results

Myelosuppression and infectious complications were the main toxicity encountered. Major dose reductions and/or treatment delays were required in all 5 patients. One patient died of septic shock. Complete remission was achieved in the remaining 4 patients with the addition of different treatment modalities. One patient had lung metastasis 3 years after starting chemotherapy, and 3 patients have remained without evidence of recurrent disease for 1–6 years from the onset of chemotherapy.

Conclusions

There is no definite answer as to whether older age is a poor prognostic factor in patients with a tumor of the Ewing's sarcoma family. In our experience, patients over 50 poorly tolerated the standard chemotherapy protocol used in the pediatric population.

Ramucirumab plus docetaxel versus placebo plus docetaxel in patients with locally advanced or metastatic urothelial carcinoma after platinum-based therapy (RANGE): a randomised, double-blind, phase 3 trial

BACKGROUND

Few treatments with a distinct mechanism of action are available for patients with platinum-refractory advanced or metastatic urothelial carcinoma. We assessed the efficacy and safety of treatment with docetaxel plus either ramucirumab-a human IgG1 VEGFR-2 antagonist-or placebo in this patient population.

METHODS

We did a randomised, double-blind, phase 3 trial in patients with advanced or metastatic urothelial carcinoma who progressed during or after platinum-based chemotherapy. Patients were enrolled from 124 sites in 23 countries. Previous treatment with one immune-checkpoint inhibitor was permitted. Patients were randomised (1:1) using an interactive web response system to receive intravenous docetaxel 75 mg/m2 plus either intravenous ramucirumab 10 mg/kg or matching placebo on day 1 of repeating 21-day cycles, until disease progression or other discontinuation criteria were met. The primary endpoint was investigator-assessed progression-free survival, analysed by intention-to-treat in the first 437 randomised patients. This study is registered with ClinicalTrials.gov, number NCT02426125.

FINDINGS

Between July, 2015, and April, 2017, 530 patients were randomly allocated either ramucirumab plus docetaxel (n=263) or placebo plus docetaxel (n=267). Progression-free survival was prolonged significantly in patients allocated ramucirumab plus docetaxel versus placebo plus docetaxel (median 4·07 months [95% CI 2·96-4·47] vs 2·76 months [2·60-2·96]; hazard ratio [HR] 0·757, 95% CI 0·607-0·943; p=0·0118). A blinded independent central analysis was consistent with these results. An objective response was achieved by 53 (24·5%, 95% CI 18·8-30·3) of 216 patients allocated ramucirumab and 31 (14·0%, 9·4-18·6) of 221 assigned placebo. The most frequently reported treatment-emergent adverse events, regardless of causality, in either treatment group (any grade) were fatigue, alopecia, diarrhoea, decreased appetite, and nausea. These events occurred predominantly at grade 1-2 severity. The frequency of grade 3 or worse adverse events was similar for patients allocated ramucirumab and placebo (156 [60%] of 258 vs 163 [62%] of 265 had an adverse event), with no unexpected toxic effects. 63 (24%) of 258 patients allocated ramucirumab and 54 (20%) of 265 assigned placebo had a serious adverse event that was judged by the investigator to be related to treatment. 38 (15%) of 258 patients allocated ramucirumab and 43 (16%) of 265 assigned placebo died on treatment or within 30 days of discontinuation, of which eight (3%) and five (2%) deaths were deemed related to treatment by the investigator. Sepsis was the most common adverse event leading to death on treatment (four [2%] vs none [0%]). One fatal event of neutropenic sepsis was reported in a patient allocated ramucirumab.

INTERPRETATION

To the best of our knowledge, ramucirumab plus docetaxel is the first regimen in a phase 3 study to show superior progression-free survival over chemotherapy in patients with platinum-refractory advanced urothelial carcinoma. These data validate inhibition of VEGFR-2 signalling as a potential new therapeutic treatment option for patients with urothelial carcinoma.

FUNDING

Eli Lilly and Company.