Additional biological and clinical characteristics to refine International Metastatic RCC Database Consortium (IMDC) prognostic/predictive assessment in metastatic renal cell carcinoma (mRCC)

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Background: mRCC prognostic stratification is currently based on the IMDC score. However, some patients experience outcomes markedly different from those predicted by the median outcome of their risk class. Moreover, risk scores are prognostic, rather than predictive, and developing reproducible, affordable, biology-based predictive biomarkers to tailor treatment choices in individual pts remains an unmet clinical need. Methods: A retrospective cohort of 113 mRCC pts treated at the Verona University Hospital Trust between 2013 and 2021 was explored to identify additional clinical prognostic factors for OS to complement IMDC score. Outlier pts (i.e. individual pts whose clinical outcome differed significantly from the median of the IMDC group they belonged to) were further explored to find putative molecular signatures, using FISH and IHC assays. Results: At a median follow-up of 69 months (range 18-136m), novel variables impacting on OS in addition to IMDC risk group were identified: bone, central nervous system (CNS) and pancreatic mets and high neutrophil/lymphocyte ratio (N/L) with a cut-off of 3.2. We also analyzed outliers: 3 good-risk pts with lower than expected OS, 4 poor-risk pts with longer than expected OS, and two intermediate-risk pts with long treatment response. Two putative signatures were found predictive of disease behavior: a cold signature (9p loss, poor of TILs) and a hot signature (rich in CD56+, CD15+ and CD8+ infiltrating cells). The cold and hot signatures were found in good risk pts with bad OS and poor-risk pts good OS, respectively; both intermediate-risk pts had a hot signature, consistent with their disease course. Conclusions: Additional clinical and molecular factors have been identified to possibly improve IMDC prognostic performance; multivariable models including them along with standard IMDC are being developed. Molecular analysis suggests potential signatures to be applied in routine clinical practice, whose predictive performance could be validated in prospective multicentric trials. [Table: see text]

Whole-body diffusion-weighted magnetic resonance imaging to assess bone response in patients with hormone-sensitive metastatic prostate cancer randomly assigned to receive androgen deprivation + enzalutamide ± zoledronic acid

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Background: Bone is frequently involved in metastatic hormone sensitive prostate cancer (mHSPC). Whole-body diffusion-weighted magnetic resonance imaging (WB-DW-MRI) is a promising imaging technique for the assessment of bone response in prostate cancer. It is not known whether the addition of antiresorptive agents can improve disease response in bone in mHSPC patients undergoing next generation hormonal agents. Methods: In this multicenter phase II study patients with de novo or relapsed mHSPC and bone metastases at bone scan were randomly allocated with a 1:1 ratio to receive either androgen deprivation therapy (ADT) plus Enzalutamide (E arm) or the same combination with the addition of Zoledronic Acid (EZ arm). The study was designed to observe a significant increase in bone response rate in the experimental arm after 12 months of treatment, as assessed through WB-DW-MRI. WB-DW-MRI was performed centrally at baseline and after 6 and 12 months and images were evaluated by the same radiologist. Results: From February 2018 to June 2021, 126 mHSPC patients were randomized, 64 in EZ arm and 62 in E arm. A total of 111 patients, 54 from E arm and 57 from EZ arm, were eligible for WB-DW-MRI assessment (15 patients were excluded because of the absence of bone target lesions at MRI or specific contraindications to MRI). Bone response at 6 months was observed in 41 patients (76%) in E arm and 41 patients (72%) in EZ arm; the corresponding bone response at 12 months were 44 (82%) and 44 (77%), respectively (OR 0.77; 95%IC 0.30-1.93; p = 0.6). Complete response was the best overall bone response after 12 months in 9 patients (17%) from E arm and in 11 patients (19%) from EZ arm. In the same period, treatment was interrupted due to disease progression in 7 (13%) and 7 (12%) patients in E and EZ arm, respectively. Conclusions: The addition of Zoledronic Acid to Enzalutamide and ADT did not improve bone disease response in patients with mHSPC. WB-DW-MRI was able to detect bone responses in a great proportion of patients. Clinical trial information: NCT03336983 .

Prognostic Value of Thyroid Hormone Ratio in Patients With Advanced Metastatic Renal Cell Carcinoma: Results From the Threefour Study (Meet-URO 14)

Background

Thyroid hormone impairment, represented as an alteration in levels of thyroid hormones and a lower fT3/fT4 ratio, has been correlated with a worse prognosis for both cancer and non-cancer patients. The role of baseline thyroid function in patients with metastatic renal cell carcinoma (mRCC) however, has not been studied yet.

Materials and Methods

We recorded clinical data, baseline biochemical results, and oncological outcomes from 10 Oncology Units in Italy. We stratified patients into three groups according to the fT3/fT4 ratio value and subsequently analyzed differences in progression-free survival (PFS) and overall survival (OS) in the three groups. We also performed univariate and multivariate analyses to find prognostic factors for PFS and OS.

Results

We analyzed 134 patients treated with systemic treatment for mRCC. Median PFS in the low, intermediate, and high fT3/fT4 ratio group were 7.5, 12.1, and 21.7 months respectively (p<0.001); median OS in the three groups were 36.5, 48.6, and 70.5 months respectively (p =0.006). The low fT3/fT4 ratio maintained its prognostic role at the multivariate analysis independently from IMDC and other well-established prognostic factors. The development of iatrogenic hypothyroidism was not associated with a better outcome.

Conclusion

We found that baseline thyroid hormone impairment, represented by a low fT3/fT4 ratio, is a strong prognostic factor in patients treated for mRCC in first line setting and is independent of other parameters currently used in clinical practice.

Use of nivolumab (N) and cabozantinib (C) for treatment of the metastatic renal cell carcinoma (mRCC) in the Veneto region: Results of AMOUR study

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Background: Second (2L) or third-line (3L) treatment options for mRCC have dramatically changed in the last years. The standard of care as per Italian Regulatory Agencies approvals is N or C. To date, there are no criteria for the choice between N and C, which both demonstrated OS gain in the pivotal trials. Methods: We planned a retrospective, real world analysis of the use of N and C as 2L and 3L treatment in 17 Oncology Units of Veneto Region. All consecutive patients (pts) with mRCC treated in advanced setting in 2017-2018 were included. Results: We identified 170 pts, 73% males, median age 68.4 years. All pts started a 2L treatment while only 59% received a 3L treatment. In our cohort, patients with NLR > 3 at treatment start had a shorter OS (43 vs 90 months (mos), p < 0.0001); IMDC classification maintained its prognostic role. In 2L, N was administrated in 108 pts (63%), C in 29 pts (17%); in 3L N was administrated in 42 pts (25%), C in 49 pts (29%). Reported oncologists’ reasons for 2L choice were: change of mechanism of action compared to first line (28%), response to previous TKI (21.2%), intolerance to TKI (17.6%), previous toxicity (12.9%), tumor burden (11.2%), age of the patient (4.1%). Median OS and PFS in 2L were 28.4 and 6.6 mos for N, 16.8 and 6.6 mos for 2L C. Median OS and PFS in 3L were 27 and 5.2 mos for N, 16.6 and 7.5 mos for C. 46 pts received the sequence of drugs N > C, 12 the opposite sequence C > N. Median OS for N > C vs C > N were 96.6 vs 36 mos (p > 0.0001); median PFS for both the sequences were similar at 5.7 mos (p = ns). The cost per patient of the sequence N > C is 51.606 € while for the sequence C > N is 31.480,00 €. Between the two sequences a cost effectiveness per month of survival analysis was performed: the cost per month of OS for the sequence N > C was 534,18 € while for the sequence C > N was 874,46 €, heavily higher. Conclusions: In our real-world setting cohort, most of the pts received N as 2L treatment and a minority received C. Outcome of single drug are superimposable to published literature. With the limits of the retrospective nature of the study, with a cost per month of OS lower a much longer OS, the sequence N > C appear to be a better treatment strategy.

MDM2 gene amplification as selection tool for innovative targeted approaches in PD-L1 positive or negative muscle-invasive urothelial bladder carcinoma

AIMS

According to The Cancer Genome Atlas (TCGA), around 9% of bladder carcinomas usually show abnormalities of the murine double minute 2 (MDM2) gene, but a few studies have been investigated them. We profiled MDM2 gene amplification in a series of urothelial carcinomas (UC) considering the molecular subtypes and expression of programmed death ligand 1 (PD-L1).

METHODS

117 patients with muscle-invasive UC (pT2-3) without (N0) or with (N+) lymph-node metastases were revised. Only cases with availability of in toto specimens and follow-up were studied. Tissue microarray was built. p53, ER, RB1, GATA-3, CK20, CK5/6, CD44 and PD-L1 (clone sp263) immunoexpression was evaluated. Fluorescent in situ hybridisation was assessed by using the HER-2/neu, FGFR-3, CDKN2A and MDM2 probes. True (ratio 12q/CEP12 >2) MDM2 gene amplification was distinguished from polyploidy/gains (ratio <2, absolute copy number of MDM-2 >2). MDM2 and PD-L1 values were correlated to the TCGA molecular phenotypes. Statistical analysis was performed.

RESULTS

6/50 (12%) cases (5 N0 and 1 N+) were amplified for MDM2 without matching to molecular phenotypes. Of 50, 14 (37%) cases expressed PD-L1 at 1% cut-off; 3/50 (9%) at >50% cut-off; of these, 2 cases on side of neoplasia among inflammatory cells. Only one out of six (17%) cases amplified for MDM2 showed expression (>50% cut-off) of PD-L1. MDM2 amplification was independent to all documented profiles (k test=0.3) and was prevalent in recurrent UC.

CONCLUSION

MDM2 amplification has been seen in both PD-L1 positive and negative muscle-invasive bladder UC independently from the TCGA molecular phenotypes. MDM2 and PD-L1 might be assessed in order to predict a better response to combo/single targeted therapies.

Impact of COVID-19 outbreak on cancer immunotherapy in Italy: a survey of young oncologists

Background

The coronavirus disease 2019 (COVID-19) pandemic has overwhelmed the health systems worldwide. Data regarding the impact of COVID-19 on cancer patients (CPs) undergoing or candidate for immune checkpoint inhibitors (ICIs) are lacking. We depicted the practice and adaptations in the management of patients with solid tumors eligible or receiving ICIs during the COVID-19 pandemic, with a special focus on Campania region.

Methods

This survey (25 questions), promoted by the young section of SCITO (Società Campana di ImmunoTerapia Oncologica) Group, was circulated among Italian young oncologists practicing in regions variously affected by the pandemic: high (group 1), medium (group 2) and low (group 3) prevalence of SARS-CoV-2–positive patients. For Campania region, the physician responders were split into those working in cancer centers (CC), university hospitals (UH) and general hospitals (GH). Percentages of agreement, among High (H) versus Medium (M) and versus Low (L) group for Italy and among CC, UH and GH for Campania region, were compared by using Fisher’s exact tests for dichotomous answers and χ² test for trends relative to the questions with 3 or more options.

Results

This is the first Italian study to investigate the COVID-19 impact on cancer immunotherapy, unique in its type and very clear in the results. The COVID-19 pandemic seemed not to affect the standard practice in the prescription and delivery of ICIs in Italy. Telemedicine was widely used. There was high consensus to interrupt immunotherapy in SARS-CoV-2–positive patients and to adopt ICIs with longer schedule interval. The majority of the responders tended not to delay the start of ICIs; there were no changes in supportive treatments, but some of the physicians opted for delaying surgeries (if part of patients’ planned treatment approach). The results from responders in Campania did not differ significantly from the national ones.

Conclusion

Our study highlights the efforts of Italian oncologists to maintain high standards of care for CPs treated with ICIs, regardless the regional prevalence of COVID-19, suggesting the adoption of similar solutions. Research on patients treated with ICIs and experiencing COVID-19 will clarify the safety profile to continue the treatments, thus informing on the most appropriate clinical conducts.

Activity of Platinum-Based Chemotherapy in Patients With Advanced Prostate Cancer With and Without DNA Repair Gene Aberrations

IMPORTANCE

DNA repair gene aberrations occur in 20% to 30% of patients with castration-resistant prostate cancer (CRPC), and some of these aberrations have been associated with sensitivity to poly(ADP-ribose) polymerase (PARP) inhibition platinum-based treatments. However, previous trials assessing platinum-based treatments in patients with CRPC have mostly included a biomarker-unselected population; therefore, efficacy in these patients is unknown.

OBJECTIVE

To characterize the antitumor activity of platinum-based therapies in men with CRPC with or without DNA repair gene alterations.

DESIGN, SETTING, AND PARTICIPANTS

In this case series, data from 508 patients with CRPC treated with platinum-based therapy were collected from 25 academic centers from 12 countries worldwide. Patients were grouped by status of DNA repair gene aberrations (ie, cohort 1, present; cohort 2, not detected; and cohort 3, not tested). Data were collected from January 1986 to December 2018. Data analysis was performed in 2019, with data closure in April 2019.

EXPOSURE

Treatment with platinum-based compounds either as monotherapy or combination therapy.

MAIN OUTCOMES AND MEASURES

The primary end points were as follows: (1) antitumor activity of platinum-based therapy, defined as a decrease in prostate-specific antigen (PSA) level of at least 50% and/or radiological soft tissue response in patients with measurable disease and (2) the association of response with the presence or absence of DNA repair gene aberrations.

RESULTS

A total of 508 men with a median (range) age of 61 (27-88) years were included in this analysis. DNA repair gene aberrations were present in 80 patients (14.7%; cohort 1), absent in 98 (19.3%; cohort 2), and not tested in 330 (65.0%; cohort 3). Of 408 patients who received platinum-based combination therapy, 338 patients (82.8%) received docetaxel, paclitaxel, or etoposide, and 70 (17.2%) received platinum-based combination treatment with another partner. A PSA level decrease of at least 50% was seen in 33 patients (47.1%) in cohort 1 and 26 (36.1%) in cohort 2 (P = .20). In evaluable patients, soft tissue responses were documented in 28 of 58 patients (48.3%) in cohort 1 and 21 of 67 (31.3%) in cohort 2 (P = .07). In the subgroup of 44 patients with BRCA2 gene alterations, PSA level decreases of at least 50% were documented in 23 patients (63.9%) and soft tissue responses in 17 of 34 patients (50.0%) with evaluable disease. In cohort 3, PSA level decreases of at least 50% and soft tissue responses were documented in 81 of 284 patients (28.5%) and 38 of 185 patients (20.5%) with evaluable disease, respectively.

CONCLUSIONS AND RELEVANCE

In this study, platinum-based treatment was associated with relevant antitumor activity in a biomarker-positive population of patients with advanced prostate cancer with DNA repair gene aberrations. The findings of this study suggest that platinum-based treatment may be considered an option for these patients.

Prognostic role of T3/T4 ratio in metastatic renal cell carcinoma (mRCC): Preliminary results of the threeFOUR multicenter study (Meet-Uro 14)

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Background: Thyroid hormones metabolism can be altered in patients (pts) with chronic diseases and/or undergoing cancer treatments. The prognostic role of T3/T4 ratio has been investigated in metastatic colorectal cancer pts in whom a high T3/T4 ratio predicted longer survival. No data are available in mRCC. Methods: We retrospectively reviewed the clinical charts of pts with mRCC treated in first line for metastatic disease at 8 Italian Oncology Units before March 2017, having at least one response assessment and baseline complete thyroid panel data available. T3/T4 was calculated as the ratio of the two value of hormones and categorized in tertiles. Results: We identified 96 pts, median age 62 years (range 27-82), 72% males. Sunitinib wad administered in 56% of pts, pazopanib in 38%, nivolumab and ipilimumab in 6%. According to Heng Score, 33% of the pts were at favorable risk, 58% at intermediate risk, 9% at poor risk. With a median follow-up time of 42.8 months, median PFS was 24.8 months, estimated median OS was 71.6 months. Tertile distribution of patients was 36.4% in the high, 29.1% in the medium and 34.5% in the low subgroup. A baseline high tertile value (≥ 0.35) predicted longer PFS (39.4 vs 21.8 1vs 4.5 months, p = 0.01), while median OS has not been reached in the three tertiles, with survival at 24 months being 69.7%, 82.1% and 91.4%, respectively in the low, medium, high group (p = ns). The high T3/T4 ratio is also strongly associated with the chance to achieve a partial or complete response (42.8% vs 39.9% vs 21%, X squared test, p < 0.001). Heng prognostic model retained its prognostic role in this cohort (median OS was 77.1 vs 48.4 vs 22.3 months, p < 0.001, respectively for favorable, intermediate or poor risk group) and also predicted PFS (median PFS 38.2 vs 17.2 vs 8.4 months, p = 0.004). Baseline NLR ≥ 3 predicted shorter OS (46.5 vs 77.1 months, p = 0.02) in the whole group. Conclusions: In our retrospective multicenter experience, a high T3/T4 ratio was associated with longer PFS and a higher probability to respond to the treatment. Median OS had not been reached for all the subgroups, probably due to a favorable patients selection. A longer follow-up is needed to validate the prognostic value of T3/T4 ratio in this cohort.

A signature of miRNAs in the blood to help prognosticate prostate cancer at the time of diagnosis

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Background: Prostate cancer (PCa) is the most commonly diagnosed cancer in men. Around 80% of PCas are diagnosed as early, localised stage yet a subset of these will metastasise and eventually prove fatal. Management decisions are based on risk stratification systems. However, these systems are not able to clearly distinguish indolent from aggressive PCa’s and as a result many patients with indolent cancers may be over treated. Circulating microRNAs (miRNA) may be an easily accessible, suitable biomarker to distinguish true indolent from clinically significant early PCas thus reducing overtreatments. Methods: Blood samples from 24 men with benign prostatic hypertrophy (BPH, n = 8), localised PCa (n = 8) or metastatic PCa (n = 8) were collected at time of diagnosis. All men had intact prostates and were naïve to any endocrine or other cancer therapy. A platform of circulating miRNAs were analysed in serum using Abcam FireflyTM technology. Data collected were independently verified using real-time qPCR (Exiqon TM ). The miRNAs identified as being significantly different between groups were then analysed in a published dataset. Results: Serum levels of seven of the miRs examined were significantly different in patients with prostate cancer compared to control across both platforms (miR-10b, miR-125b, miR-210, miR-21, miR-378a, miR-483 and miR93 all with P values < 0.005). A further four miRNAs could differentiate between the benign and metastatic cohorts (miR-126 P = 0.008, miR-150 P = 0.05, miR375 P = 0.007). Kaplein-Meier analysis further identified that the serum levels of four miRNAs showed significant association with survival rates (miR-21 P = 0.032, miR-126 P = 0.032, miR-150 P = 0.032, miR-93 P = 0.019). On examination in a cohort of 280 men from The Cancer Genome Atlas (TCGA), four miRs from the cohort had significantly different expression in patients who eventually relapsed (miR-21 P = 0.048, miR-375 P = 0.021, miR-210 P = 0.0003, miR-93 P = 0.008) Conclusions: Our circulating miRNA based signature could be used to stratify men at prostate cancer diagnosis and help identify those who are likely to harbour micro metastases and would benefit more from an early radical treatment. The data is being validated in larger cohorts.

A circulating miRNA signature to help prognosticate at prostate cancer diagnosis

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Background: Prostate cancer (PCa) is the most commonly diagnosed cancer in men. Around 80% of PCas are diagnosed as early, localised stage yet a subset of these will metastasise and eventually prove fatal. Management decisions are based on risk stratification systems. However, these systems are not able to clearly distinguish indolent from aggressive PCa’s and as a result many patients with indolent cancers may be over treated. Circulating microRNAs (miRNA) may be an easily accessible, suitable biomarker to distinguish true indolent from clinically significant early prostate cancers (PCa) thus reducing overtreatments. Methods: Blood samples from 24 men with benign prostatic hypertrophy (BPH, n = 8), localised PCa (n = 8) or metastatic PCa (n = 8) were collected at time of diagnosis. All men had intact prostates and were naïve to any endocrine or other cancer therapy. A platform of circulating miRNAs were analysed in serum using Abcam Firefly technology. Data collected were independently verified using real-time qPCR (Exiqon). The miRNAs identified as being significantly different between groups were then analysed in a published dataset. Results: Serum levels of seven of the miRs examined were significantly different in patients with prostate cancer compared to control across both platforms (miR-10b, miR-125b, miR-210, miR-21, miR-378a, miR-483 and miR93 all with P values < 0.005). A further four miRNAs could differentiate between the benign and metastatic cohorts (miR-126 P = 0.008, miR-150 P = 0.05, miR375 P = 0.007). Kaplein-Meier analysis further identified that the serum levels of four miRNAs showed significant association with survival rates (miR-21 P = 0.032, miR-126 P = 0.032, miR-150 P = 0.032, miR-93 P = 0.019). On examination in a cohort of 280 men from The Cancer Genome Atlas (TCGA), four miRs from the cohort had significantly different expression in patients who eventually relapsed (miR-21 P = 0.048, miR-375 P = 0.021, miR-210 P = 0.0003, miR-93 P = 0.008) Conclusions: Our circulating miRNA based signature could be used to stratify men at prostate cancer diagnosis and help identify those who are likely to harbour micro metastases and would benefit more from an early radical treatment. The data is being validated in larger cohorts.

Amplification-Free Detection of Circulating microRNA Biomarkers from Body Fluids Based on Fluorogenic Oligonucleotide-Templated Reaction between Engineered Peptide Nucleic Acid Probes: Application to Prostate Cancer Diagnosis

Highly abundant in cells, microRNAs (or miRs) play a key role as regulators of gene expression. A proportion of them are also detectable in biofluids making them ideal noninvasive biomarkers for pathologies in which miR levels are aberrantly expressed, such as cancer. Peptide nucleic acids (PNAs) are engineered uncharged oligonucleotide analogues capable of hybridizing to complementary nucleic acids with high affinity and high specificity. Herein, novel PNA-based fluorogenic biosensors have been designed and synthesized that target miR biomarkers for prostate cancer (PCa). The sensing strategy is based on oligonucleotide-templated reactions where the only miR of interest serves as a matrix to catalyze an otherwise highly unfavorable fluorogenic reaction. Validated in vitro using synthetic RNAs, these newly developed biosensors were then shown to detect endogenous concentrations of miR in human blood samples without the need for any amplification step and with minimal sample processing. This low-cost, quantitative, and versatile sensing technology has been technically validated using gold-standard RT-qPCR. Compared to RT-qPCR however, this enzyme-free, isothermal blood test is amenable to incorporation into low-cost portable devices and could therefore be suitable for widespread public screening.

Volume of Bone Metastasis Assessed with Whole-Body Diffusion-weighted Imaging Is Associated with Overall Survival in Metastatic Castration-resistant Prostate Cancer

Purpose To determine the correlation between the volume of bone metastasis as assessed with diffusion-weighted (DW) imaging and established prognostic factors in metastatic castration-resistant prostate cancer (mCRPC) and the association with overall survival (OS). Materials and Methods This retrospective study was approved by the institutional review board; informed consent was obtained from all patients. The authors analyzed whole-body DW images obtained between June 2010 and February 2013 in 53 patients with mCRPC at the time of starting a new line of anticancer therapy. Bone metastases were identified and delineated on whole-body DW images in 43 eligible patients. Total tumor diffusion volume (tDV) was correlated with the bone scan index (BSI) and other prognostic factors by using the Pearson correlation coefficient (r). Survival analysis was performed with Kaplan-Meier analysis and Cox regression. Results The median tDV was 503.1 mL (range, 5.6-2242 mL), and the median OS was 12.9 months (95% confidence interval [CI]: 8.7, 16.1 months). There was a significant correlation between tDV and established prognostic factors, including hemoglobin level (r = -0.521, P < .001), prostate-specific antigen level (r = 0.556, P < .001), lactate dehydrogenase level (r = 0.534, P < .001), alkaline phosphatase level (r = 0.572, P < .001), circulating tumor cell count (r = 0.613, P = .004), and BSI (r = 0.565, P = .001). A higher tDV also showed a significant association with poorer OS (hazard ratio, 1.74; 95% CI: 1.02, 2.96; P = .035). Conclusion Metastatic bone disease from mCRPC can be evaluated and quantified with whole-body DW imaging. Whole-body DW imaging-generated tDV showed correlation with established prognostic biomarkers and is associated with OS in mCRPC. (©) RSNA, 2016 Online supplemental material is available for this article.

Phase I trial outcomes in older patients with advanced solid tumours

Background:

This study had two aims: (a) to test the hypothesis that advanced age is associated with lower levels of tolerability and clinical benefit to experimental Phase I trial agents; (b) to assess the validity of the Royal Marsden Hospital (RMH) prognostic score as a patient selection tool in older patients.

Methods:

Clinico-pathological characteristics and treatment outcomes of all patients treated consecutively from 2005 to 2009 in phase I trials at the RMH were recorded. All toxicity and clinical outcome data were compared between patients aged below and above 65 years of age.

Results:

One thousand and four patients were treated in 30 Phase I trials, with 315 (31%) patients aged 65 years and older. Grade 3–5 toxicities (22.8% vs 24.8% (P=0.52)), trial discontinuation (6% vs 4% P=0.33), and dose interruptions (8.0% vs 8.0% (P=0.96)) were observed at similar rates in patients below and above 65 years of age, respectively. The overall response rate 5.2% vs 4.1%, progression-free survival (PFS) 1.9 vs 3.5 months and clinical benefit rate (CBR) at 6 months 15.2% vs 14.3% were comparable in both groups. To avoid bias due to the potential therapeutic benefit of abiraterone, comparisons were repeated excluding prostate cancer patients with similar results (ORR 4.6% vs 4%, PFS 1.8 vs 3.0 months, CBR at 6 months 13.5% vs 9.5%). Multivariate analysis indicated that the previously identified RMH score (including albumin and lactate dehydrogenase levels) was an accurate predictor of outcome.

Conclusions:

Phase I clinical trials should be considered in patients with advanced cancers regardless of age, as older patients who enter these have similar safety and efficacy outcomes as their younger counterparts. The RMH prognostic score can assist in the selection of suitable older patients.

AZD3514, an oral selective androgen receptor down-regulator in patients with castration-resistant prostate cancer - results of two parallel first-in-human phase I studies

BACKGROUND

AZD3514 is a first-in-class, orally bio-available, androgen-dependent and -independent androgen receptor inhibitor and selective androgen-receptor down-regulator (SARD).

METHODS

In study 1 and 2, castration-resistant prostate cancer (CRPC) patients (pts) were initially recruited into a once daily (QD) oral schedule (A). In study 1, pharmacokinetic assessments led to twice daily (BID) dosing (schedule B) to increase exposure. Study 2 explored a once daily schedule.

RESULTS

In study 1, 49 pts were treated with escalating doses of AZD3514 (A 35 pts, B 14 pts). Starting doses were 100 mg (A) and 1000 mg (B). The AZD3514 formulation was switched from capsules to tablets at 1000 mg QD. 2000 mg BID was considered non-tolerable due to grade (G) 2 toxicities (nausea [N], vomiting [V]). No adverse events (AEs) met the dose-limiting toxicity (DLT) definition. Thirteen pts received AZD3514 in study 2, with starting doses of 250 mg QD. The most frequent drug-related AEs were N: G1/2 in 55/70 pts (79 %); G3 in 1 pt (1.4 %); & V: G1/2 in 34/70 pts (49 %) & G3 in 1 pt (1.4 %). PSA declines (≥50 %) were documented in 9/70 patients (13 %). Objective soft tissue responses per RECIST1.1 were observed in 4/24 (17 %) pts in study 1.

CONCLUSION

AZD3514 has moderate anti-tumour activity in pts with advanced CRPC but with significant levels of nausea and vomiting. However, anti-tumour activity as judged by significant PSA declines, objective responses and durable disease stabilisations, provides the rationale for future development of SARD compounds.

First-in-human study of CH5132799, an oral class I PI3K inhibitor, studying toxicity, pharmacokinetics, and pharmacodynamics, in patients with metastatic cancer

PURPOSE

This phase I dose-escalation study investigated the maximum-tolerated dose (MTD), dose-limiting toxicities (DLT), safety, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary clinical activity of CH5132799.

EXPERIMENTAL DESIGN

Patients with metastatic solid tumors were eligible for the study. CH5132799 was administered orally once daily or twice daily in 28-day cycles.

RESULTS

Thirty-eight patients with solid tumors received CH5132799 at 2 to 96 mg once daily or 48 to 72 mg twice daily. The MTD was 48 mg on the twice-daily schedule but was not reached on the once daily schedule. DLTs were grade 3 elevated liver function tests (LFT), grade 3 fatigue, grade 3 encephalopathy, grade 3 diarrhea, and grade 3 diarrhea with grade 3 stomatitis; all DLTs were reversible. Most drug-related adverse events were grade 1/2. Diarrhea (34%) and nausea (32%) were the most common events. Mean Cmax and AUC0-24 in steady state at MTD were 175 ng/mL and 1,550 ng·h/mL, respectively, consistent with efficacious exposure based on preclinical modeling. Reduction in SUVmax with [(18)F] fluorodeoxyglucose positron emission tomography (FDG-PET) was observed in 5 of 7 patients at MTD. A patient with PIK3CA-mutated clear cell carcinoma of the ovary achieved a partial response by GCIG CA125 criteria and further, a heavily pretreated patient with triple-negative breast cancer had marked improvement in her cutaneous skin lesions lasting six cycles.

CONCLUSION

CH5132799 is well tolerated at the MTD dose of 48 mg twice daily. At this dose, the drug had a favorable PK and PD profile and preliminary evidence of clinical activity.

First-in-human Phase I study of EZN-4176, a locked nucleic acid antisense oligonucleotide to exon 4 of the androgen receptor mRNA in patients with castration-resistant prostate cancer

BACKGROUND

Prostate cancer remains dependent of androgen receptor (AR) signalling, even after emergence of castration resistance. EZN-4176 is a third-generation antisense oligonucleotide that binds to the hinge region (exon 4) of AR mRNA resulting in full-length AR mRNA degradation and decreased AR protein expression. This Phase I study aimed to evaluate EZN-4176 in men with castration-resistant prostate cancer (CRPC).

METHODS

Patients with progressing CRPC were eligible; prior abiraterone and enzalutamide treatment were allowed. EZN-4176 was administered as a weekly (QW) 1-h intravenous infusion. The starting dose was 0.5 mg kg(-1) with a 4-week dose-limiting toxicity (DLT) period and a 3+3 modified Fibonacci dose escalation design. After determination of the DLT for weekly administration, an every 2 weeks schedule was initiated.

RESULTS

A total of 22 patients were treated with EZN-4176. At 10 mg kg(-1) QW, two DLTs were observed due to grade 3-4 ALT or AST elevation. No confirmed biochemical or soft tissue responses were observed. Of eight patients with <5 circulating tumour cells at baseline, a conversion to <5 was observed in three (38%) patients. The most common EZN-4176-related toxicities (all grades) were fatigue (59%), reversible abnormalities in liver function tests ALT (41%) and AST (41%) and infusion-related reactions including chills (36%) and pyrexia (14%).

CONCLUSION

Activity of EZN-4176 at the doses and schedules explored was minimal. The highest dose of 10 mg kg(-1) QW was associated with significant but reversible transaminase elevation.

Abstract C173: A first-in-human Phase I study of DS-3078a, an oral TORC1/2 inhibitor, in patients with advanced solid tumors: Preliminary results

Background: The phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway is frequently deregulated in cancer due to mutations in PIK3CA and AKT, hyperactivation of upstream receptor kinases, and loss of function of PTEN. DS-3078a is a dual inhibitor of mTOR complex 1 (TORC1) and 2 (TORC2) that modulate the PI3K/AKT/mTOR pathway. This first-in-human study was conducted to determine the safety, tolerability, maximum tolerated dose (MTD), pharmacokinetics (PK), and pharmacodynamics (PD) of DS-3078a.

Methods: Dose escalation was performed using an accelerated titration method with single patient cohorts starting at 20 mg followed by a continuous reassessment method according to a Bayesian regression logistic model. DS-3078a was administered orally in a continuous once daily (QD) schedule in 28-day cycles. PK parameters including area under the curve (AUC) and maximum plasma concentration (Cmax) were assessed on cycle 1 days 1 and 8. PD analyses were performed on cycle 1 days 1 and 15 in platelet-rich plasma (PRP) for changes in phospho-AKT and, when available, in paired tumor biopsies for phospho-AKT and -S6.

Results: Seventeen patients (pts) with a median age of 61 years (range 38-72 years) were evaluable for dose limiting toxicities (DLT) according to NCI-CTCAE v 4.0. Mesothelioma (n=4) and neuroendocrine carcinoma (n=3) were the most common tumor types. Other tumor types included adenoid cystic, renal, ovarian, cervical, peritoneal, colorectal, and lung carcinoma, and unknown primary. Pts were treated at seven different dose levels of DS-3078a (20, 40, 80, 160, 320, 450, and 640 mg). MTD had been exceeded at 640 mg with DLT of grade 3 vomiting and grade 2 refractory nausea resulting in two pts not being able to complete 75% of the cycle 1 dose. The lower dose of 450 mg QD was well tolerated by 6 pts and 4 additional pts will be treated at this dose level to confirm MTD. The most common non-DLT drug-related toxicities at any cycle included grade ≤2 nausea (61%), vomiting (56%), diarrhea (50%), fatigue (33%), anorexia (28%), mucositis (28%), and hyperglycemia (17%). The mean Cmax and AUC value on day 1 at 450 mg QD was 542 ng/ml and 1898 ng.h/ml, respectively. Preliminary PD data showed up to 89% inhibition of Akt phosphorylation in platelets and up to 60% inhibition retained at 24 hours post-dose at ≥320 mg QD in some pts. The best response according to RECIST v1.1 was stable disease ≥6 months in 3 pts (ovarian, renal, and peritoneal carcinoma) with minor tumor response observed in a pt with renal carcinoma.

Conclusion: DS-3078a was well tolerated up to and pharmacodynamically active at 450 mg QD. A continuous twice daily dosing schedule has been opened to explore other schedules which may optimize the biological effects of DS-3078a. Clinical trial information NCT01588676.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):C173.

Citation Format: Marta Capelan, Prasana Kumar, Anthony W. Tolcher, Andrea Zivi, Madhuri Desai, Kyriakos P. Papadopoulos, Giorgio Senaldi, Amita Patnaik, Udai Banerji, Drew D. Rasco. A first-in-human Phase I study of DS-3078a, an oral TORC1/2 inhibitor, in patients with advanced solid tumors: Preliminary results. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr C173.

Antitumour activity of enzalutamide (MDV3100) in patients with metastatic castration-resistant prostate cancer (CRPC) pre-treated with docetaxel and abiraterone

BACKGROUND

The new generation anti-androgen enzalutamide and the potent CYP17 inhibitor abiraterone have both demonstrated survival benefits in patients with metastatic castration-resistant prostate cancer (CRPC) progressing after docetaxel. Preliminary data on the antitumour activity of abiraterone after enzalutamide have suggested limited activity. The antitumour activity and safety of enzalutamide after abiraterone in metastatic CRPC patients is still unknown.

PATIENTS AND METHODS

We retrospectively identified patients treated with docetaxel and abiraterone prior to enzalutamide to investigate the activity and safety of enzalutamide in a more advanced setting. Prostate specific antigen (PSA), radiological and clinical assessments were analysed.

RESULTS

39 patients with metastatic CRPC were identified for this analysis (median age 70years, range: 54-85years). Overall 16 patients (41%) had a confirmed PSA decline of at least 30%. Confirmed PSA declines of ⩾50% and ⩾90% were achieved in 5/39 (12.8%) and 1/39 (2.5%) respectively. Of the 15 patients who responded to abiraterone, two (13.3%) also had a confirmed ⩾50% PSA decline on subsequent enzalutamide. Among the 22 abiraterone-refractory patients, two (9%) achieved a confirmed ⩾50% PSA decline on enzalutamide.

CONCLUSION

Our preliminary case series data suggest limited activity of enzalutamide in the post-docetaxel and post-abiraterone patient population.

A first-in-human study of the oral selective androgen receptor down-regulating drug (SARD) AZD3514 in patients with castration-resistant prostate cancer (CRPC)

4511

Background: AZD3514 is a first in class, orally bio-available drug that inhibits androgen-dependent and –independent androgen receptor (AR) signaling through two distinct mechanisms; inhibition of ligand-driven nuclear AR translocation and down-regulation of AR levels. Methods: A rolling six design was employed initially using a once a day (QD) schedule (A). PK assessments led to a change to twice daily (BD) dosing (B) to increase exposure. PK profiles were studied over 96 hours after a single dose and over 24 hours at start of/following 21 days continuous dosing. PD analyses included PSA and CTC quantification. Results: 49 CRPC patients (pts) have been treated with escalating doses of AZD3514 (A 35 pts, B 14 pts). Starting doses were 100 mg (A) and 1000 mg (B). The AZD3514 formulation was switched from capsules to tablets at 1000mg (QD). 2000mg BD was considered non-tolerable due to multiple grade 2 toxicities (nausea [N], vomiting [V], fatigue). No adverse events (AEs) met the DLT definition. The most frequent drug-related AE’s were N; G1/2 36/49 (73%), G3 2/49 (4%) and V; G1/2 24/49 (49%) & G3 3/49 (6%). N/V were managed with oral anti-emetics. Dose proportional increases in plasma concentrations were observed following a single dose. Geometric mean (%CV) Cmax and AUC at MTD were 9,608 (38.5) ng/mL and 61,734 (40.6) ng.hr/mL, respectively. Compared with single dose continuous dosing led to a mean decrease of 26% in exposure. Maximum PSA and CTC declines are summarized below. Objective soft tissue responses per RECIST1.1 were observed in 2/26 (8%) pts. One pt with abiraterone resistant disease remained on study for 19 months. At 6 and 12 months 21 (43%) and 8 (16%) pts remained on study without evidence of bone or soft tissue progression, respectively. Conclusions: AZD3514 has antitumor activity in patients with advanced CRPC. Clinical trial information: NCT01162395. [Table: see text]

A first-in-human phase I trial of AR-12, a PDK-1 inhibitor, in patients with advanced solid tumors

2608

Background: AR-12 (OSU-03012) is an oral celecoxib analogue lacking COX-2 inhibitory activity that inhibits pyruvate dehydrogenase kinase isoenzyme 1 (PDK-1), AKT and impacts the endoplastic reticulum stress pathway. Preclinical studies indicate antitumor activity of AR-12 in various models and enhanced activity in combination. We completed a first in human clinical trial to determine its safety and tolerability, maximum tolerated dose (MTD) and recommended phase II dose (RD). Secondary objectives included assessment of tumor response, pharmacokinetics (PK) and pharmacodynamics (PD) including food effect. Methods: Patients (pts) with advanced solid tumors, ECOG PS 0-1, and adequate organ function were recruited in a modified 3+3 dose-escalation study. Pts received a run-in dose of AR-12 to analyze PK-PD and food effect, followed by continuous daily (QD) dosing in 28-day cycles. A twice daily (BID) cohort was initiated based on safety data. PD analysis was performed in platelet-rich plasma (PRP) and paired tumor biopsies when feasible. Results: 35 pts received at least one dose of study drug; 30 were evaluable for dose limiting toxicities (DLT) at dose ranges 100-3200mg QD and 800-1600mg BID. No DLT were observed in the QD cohort; DLT in the BID cohort are listed in table 1. Drug-related events (NCI-CTCAE v3) included rash (G2-2pts; G3-1pt), fatigue (G2-2pts; G3-4pts), nausea (G2-7pts; G3-1pt) and bloating (G2-1pt). Cmax after single dose was dose-proportional but high PK variability was observed, likely due to inadequate disintegration and dissolution of the formulation in the stomach. At RD, partial GSK3ß inhibition in PRP after 4 hours suggests AKT-pathway modulation. Best response (RECIST v1.0) was stable disease >6 cycles for 2 pts. Conclusions: The RD based on safety data is 800mg BID. Signs of pathway modulation were observed in concordance with the expected mechanism of action but were short-lasting. Considering limited drug absorption and PK variability, a new formulation of the drug will be developed to overcome these limitations. Clinical trial information: NCT00978523. [Table: see text]

First-in-human phase I study of EZN-4176, a locked nucleic acid antisense oligonucleotide (LNA-ASO) to androgen receptor (AR) mRNA in patients with castration-resistant prostate cancer (CRPC)

5052

Background: EZN-4176 is a third generationLNA-ASO that binds the ligand binding domain of AR mRNA resulting in full length AR mRNA degradation and decreased AR protein expression. Methods: Patients (pts) (performance status ECOG≤1) with progressing CRPC were eligible; prior abiraterone and enzalutamide treatment were allowed. EZN-4176 was administered as a weekly (QW) one-hour intravenous infusion. The starting dose was 0.5 mg/Kg with a 4-week dose-limiting toxicity (DLT) period. After determination of the DLT and the maximum tolerated dose (MTD) for weekly administration, a fortnightly schedule (Q2W) was initiated; a 3+3 modified Fibonacci dose escalation design was pursued. PD studies evaluated AR expression in tissue utilizing antibodies to the amino and carboxy-termini of the AR. Results: 22 pts were enrolled (median age 70.6 years, range 59 – 84 years). One pt was treated with the Q2W schedule. Two DLTs (G3/G4 ALT/AST elevation) occurred at 10 mg/Kg, which was therefore identified as the MTD for the weekly schedule. Multiple pts treated at 6.5 and 10 mg/Kg (5/9 pts, 55%) developed ≥G2 ALT and/or AST elevation after the first cycle requiring dose reduction and treatment delay. The most frequent adverse events (AEs) all-grades were fatigue (21/22 pts, 95.4%), nausea (10/22 pts, 45.4%), constipation (8/22 pts, 36.3%), AST (8/22 pts, 36.3%) and ALT (10/22 pts, 45.4%) elevation. The most frequent G3/4 AEs were AST (4/22 pts, 18.1%) and ALT (5/22 pts, 22.7%) elevation. Maximum PSA and circulating tumor cells (CTCs) declines are summarized below. There were no objective soft tissue responses. PD studies did not document any knockdown of AR expression Conclusions: EZN-4176 has limited antitumour activity in CRPC at its MTD for weekly administration. Safety, PK, PD and efficacy data will be presented. Clinical trial information: NCT01337518. [Table: see text]

Antitumour activity of docetaxel following treatment with the CYP17A1 inhibitor abiraterone: clinical evidence for cross-resistance?

BACKGROUND

Abiraterone and docetaxel are both approved treatments for men with metastatic castration-resistant prostate cancer (mCRPC). Abiraterone pre-docetaxel is currently undergoing evaluation in a phase III study. In vitro studies indicate that taxanes may act by disrupting androgen receptor signalling. We hypothesised that prior abiraterone exposure would adversely impact docetaxel efficacy.

PATIENTS AND METHODS

We retrospectively evaluated activity of docetaxel in mCRPC patients previously treated with abiraterone, using Prostate Cancer Working Group and radiological criteria.

RESULTS

Of the 54 patients treated with abiraterone, 35 subsequently received docetaxel. Docetaxel resulted in a prostate-specific antigen (PSA) decline of ≥50% in nine patients [26%, 95% confidence interval (CI) 13% to 43%], with a median time to PSA progression of 4.6 months (95% CI 4.2% to 5.9%). PSA declines ≥30% were achieved by 13 patients (37%, 95% CI 22% to 55%). The median overall survival was 12.5 months (95% CI 10.6-19.4). All patients who failed to achieve a PSA fall on abiraterone and were deemed abiraterone-refractory were also docetaxel-refractory (N = 8). In the 24 patients with radiologically evaluable disease, partial responses were reported in four patients (11%), none of whom were abiraterone-refractory.

CONCLUSION

The activity of docetaxel post-abiraterone appears lower than anticipated and no responses to docetaxel were observed in abiraterone-refractory patients.

Durable radiologic and clinical disease stability beyond PSA progression in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone acetate (AA)

4553

Background: AA, a potent oral CYP17A1 inhibitor is approved for treatment of mCRPC with a survival advantage of 4.9 months. In clinical practice, response evaluation remains challenging for pts with mCRPC. CTC conversion from CTC ≥ 5 to CTC < 5 with treatment predicts for improved overall survival in mCRPC. We hypothesized that pts continue to have durable disease stability beyond PSA progression on AA. Methods: Prostate Specific Antigen (PSA) responses, radiological responses and CTC conversion rates were retrospectively analysed in pts treated on AA at our institution. CTCs, PSA and imaging were obtained at predefined time points during these studies. Radiological and PSA progression were defined by standard Prostate Cancer Working Group Criteria II. Clinical progression consisted of worsening disease related pain, skeletal events or declining performance status.Pearson’s chi-squared test and the Kaplan-Meier method were used for this analysis. Results: 141 patients [ECOG Performance Status 0-2; Median Age: 69.7 (range 44.7-87.1); 85 post-docetaxel, 56 pre-docetaxel] received AA. The median duration of clinical and radiological stable disease (SD) was 16.8 months (n=55) and 5.6 months (n=75) in patients with a baseline CTCs count of ≤ 5 cells/7.5mls and ≥ 5 cells/7.5 mls respectively. In the 105 patients with documented PSA progression on AA there was a median 5.7-month delay in detecting radiological and/or clinical progression (95% CI: 4.2, 8.4; range 0.3, 35.6 months). Radiological and clinical SD of ≥ 1 year, ≥ 2 years and ≥ 3 years on AA was observed in 43/141 (30.5%), 21/141 (14.9%) and 12/141 (8.5%) respectively. Conclusions: Radiological and clinical disease stabilization beyond PSA progression is maintained in a high proportion of mCRPC patients treated with AA. Future studies should evaluate whether continued AA treatment beyond PSA and radiological progression can impact outcome.

Phase II escalation study of sorafenib in patients with metastatic renal cell carcinoma who have been previously treated with anti-angiogenic treatment

OBJECTIVE

To assess both clinical and biological efficacy and toxicity of sorafenib in patients with metastatic renal cell carcinoma (mRCC) previously treated with an anti-angiogenic vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor.

METHODS

Sorafenib is an orally active multikinase inhibitor approved for the treatment of mRCC. Drug-focused translational research on tissues (i.e. B-RAF) and plasma (VEGFR-α, circulating endothelial cells, endothelial progenitor cells) was performed to define biological predictive and prognostic markers and their related kinetics. Patients with mRCC pretreated with an anti-angiogenic treatment, an Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-2 and adequate organ function were eligible. Patients received sorafenib 400 mg twice a day continuously in 4-week cycles. Patients with no progressive disease at 12 weeks continued to receive sorafenib at the standard dose, whereas progressing patients received an increased dose (600 mg twice a day) with early disease restaging after 4 weeks. Patients who progressed at 600 mg twice a day went off study. Efficacy (overall tumour control) was assessed by Response Evaluation Criteria in Solid Tumors.

RESULTS

In all, 19 patients were entered. The baseline characteristics were as follows: ECOG PS 0-1 94.8%; median (range) age 62 (41-81) years; nephrectomy 100%; surgery for metastatic disease 26.4%; clear cell 79.1%; papillary cell 15.7%; sarcomatoid/high grade 5.2%; two or more metastatic sites 84%. Overall, 11 patients (58%) had disease control at 6 months without significant correlation between response to prior therapy and hypertension. Progression-free survival (PFS) of 8.3 months was observed. Of six patients for whom the dose was escalated due to early progression, three benefitted with PFS of >3 months. Three (15.7%) of 19 patients had a V600E mutation and one had a K601E mutation; PFS appeared to be substantially shorter in these patients compared with 15 patients with wild-type B-RAF (2.5 vs 9.1 month, P < 0.05). The most common toxicity (National Cancer Institute Common Toxicity Criteria, NCIC 3.0, all patients) was grade ≥1 diarrhoea and grade 2-3 hand-foot syndrome in 11 patients. Grade 3 mucositis was observed in one patient.

CONCLUSIONS

Sorafenib at doses of 400-600 mg twice a day continuously results in acceptable and well tolerated salvage treatment after VEGFR tyrosine kinase inhibitor failure. In progressive patients, treatment with a higher dose could be a valid option and B-RAF mutations may be an interesting predictive marker to be studied in a larger randomized trial.

Response to abiraterone acetate in the postchemotherapy setting in patients with castration-resistant prostate cancer whose disease progresses early on docetaxel

17

Background: Abiraterone acetate (AA) has recently been approved for men with metastatic castration-resistant prostate cancer (CRPC) following docetaxel chemotherapy. AA inhibits CYP17, reducing androgen production and thereby impacting androgen receptor (AR) signalling. Recent evidence suggests taxanes also impact AR signalling, raising concerns about potential cross-resistance. We have previously shown that docetaxel has no antitumor activity in AA refractory patients. We have now evaluated the antitumor activity of AA post-docetaxel to determine the activity of AA in docetaxel refractory patients.

Methods: Forty four men with CRPC treated with docetaxel (75 mg/m2 every 21 days) followed by post-chemotherapy AA at the Royal Marsden Hospital were identified. Radiological response by RECIST, PSA response by PSAWG2 criteria and symptomatic benefit were evaluated.

Results: An average of 9 cycles of docetaxel were given (range 3-17); 7 patients discontinued chemotherapy due to progression of disease and 10 for toxicity. Of 40 patients with PSA data available, 26 (65%) had a PSA decline of at least 50%. At commencement of AA, median age was 68 years. Bone, nodal and visceral metastases were present in 38 (86%), 23 (52%) and 6 (14%) of the cohort respectively. An average of 5 months of treatment were delivered and 23 patients continue on AA. Of the 44, 7 (16%) patients had a 50% or greater PSA decline on AA. None of the 7 patients who were docetaxel refractory had a subsequent PSA, radiological or clinical response to AA. Of the 6 patients who received less than 5 cycles of docetaxel due to toxicity, 2 had subsequent PSA response on AA. There was no relationship between length of time on LHRH agonist and PSA response to AA.

Conclusions: Our data suggest that patients who are refractory to docetaxel do not respond to AA. Overall, in conjunction with our other evidence that in AA-refractory patients docetaxel has no antitumor activity, these data provide further evidence for cross-resistance between these two agents.

Abstract C9: Treatment response to abiraterone acetate (AA) in patients with castration-resistant prostate cancer (CRPC) based on circulating tumor cells (CTCs), prostate-specific antigen (PSA), and imaging

Background: AA, a potent oral irreversible inhibitor of CYP17A1, has been recently approved for patients with CRPC progressing after docetaxel. CTC count ≥ 5/7.5 ml correlates with worse survival in CRPC. In this analysis we evaluated PSA responses, radiological responses and CTC conversion rates in relation to patient outcome.

Methods: 141 patients (ECOG Performance Status 0-2; Median Age: 69.7; 85 post-docetaxel, 56 pre-docetaxel) treated with AA at the Royal Marsden NHS Foundation Trusts between December 2005 and March 2011 were included in this retrospective analyses. CTCs were enumerated using CellSearch at screening, baseline, at multiple time points during the study and at treatment discontinuation. PSA and imaging (Computer Tomography and Bone Scans) were obtained at the same time points as CTC collection. The Kaplan-Meier method was utilized for these analyses.

Results: Baseline CTCs of ≥ 5 cells/7.5 ml were detectable in 17/53 (32.1%) pre-docetaxel patients (3 inevaluable) and 58/77 (75.3%) post-docetaxel patients (8 inevaluable at baseline). CTC conversion (≥ 5 to &lt; 5 cells/7.5 ml) was observed in 10/17 (58.8%) pre-docetaxel patients and in 12/52 (23.1%) (6 inevaluable) post-docetaxel patients. PSA responses by PCWG II were observed in 16/22 (72.7%) of patients who attained a CTC conversion. PSA responses were seen in 8/47 (17.0%) patients in the absence of a corresponding CTC conversion. The median duration of radiological SD was 12.13 months (n=55) and 5.4 months (n=75) in patients with a baseline CTCs count of ≤ 5 cells/7.5mls and ≥ 5 cells/7.5 mls respectively. Overall, radiological stable disease was observed for a median of 6 months (95% CI: 4.2, 8.4; range 0.3, 35.6) beyond PSA progression in the 105 patients who experienced PSA progression. Radiological and clinical disease stability during treatment of ≥ 1 year, ≥ 2 years and ≥ 3 years was observed in 43/141 (30.5%), 21/141 (14.9%) and 12/141 (8.5%) respectively.

Conclusion: Radiological and clinical disease stabilization beyond PSA progression is seen in a significant proportion of patients treated with AA. CTCs conversion correlates with PSA response and radiological disease stability.

Citation Format: Diletta Bianchini, Alison Reid, Gerhardt Attard, Johann De Bono, Shahneen Sandhu, Amy Cassidy Mulick, Deborah Mukherji, Carmel Pezaro, Andrea Zivi, Aurelius Omlin, Ajit Sarvadikar, Emilda Thompson. Treatment response to abiraterone acetate (AA) in patients with castration-resistant prostate cancer (CRPC) based on circulating tumor cells (CTCs), prostate-specific antigen (PSA), and imaging [abstract]. In: Proceedings of the AACR Special Conference on Advances in Prostate Cancer Research; 2012 Feb 6-9; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2012;72(4 Suppl):Abstract nr C9.

Horizon scanning for novel therapeutics for the treatment of prostate cancer

Treatment options for patients with advanced prostate cancer (PCa) remain limited. Improved understanding of the underlying molecular drivers of PCa pathogenesis, progression and resistance development has provided the fundamental basis for rational targeted drug design. Key findings in recent years include the identification of ETS gene rearrangements, the dissection of PCa molecular heterogeneity and the discovery that castration-resistant prostate cancer (CRPC) remains androgen driven despite the androgen-depleted milieu, thus making androgen receptor (AR) signaling a continued focus of molecularly targeted treatments. AR ligand-independent activation of tyrosine kinase prosurvival signaling cascades and angiogenesis have also been implicated in disease progression. A multitude of new molecularly targeted agents that abrogate AR signaling, inhibit the mitogenic and prosurvival signal transduction pathways, perturb the tumor-bone microenvironment, impair tumor vasculature, facilitate immune modulation and induce apoptosis are in clinical development and are highly likely to change the current treatment paradigm. It is clear that the success of these molecular targeted therapies hinges in part on optimal patient selection based on the molecular disease profile and an improved understanding of the mechanistic basis of acquired resistance. This review outlines the current clinical development of molecular targeted treatments in CRPC, with particular emphasis on agents that are in the later stages of clinical development, and details the challenges and future direction of developing these antitumor agents.

The changing therapeutic landscape of castration-resistant prostate cancer

Castration-resistant prostate cancer (CRPC) has a poor prognosis and remains a significant therapeutic challenge. Before 2010, only docetaxel-based chemotherapy improved survival in patients with CRPC compared with mitoxantrone. Our improved understanding of the underlying biology of CRPC has heralded a new era in molecular anticancer drug development, with a myriad of novel anticancer drugs for CRPC entering the clinic. These include the novel taxane cabazitaxel, the vaccine sipuleucel-T, the CYP17 inhibitor abiraterone, the novel androgen-receptor antagonist MDV-3100 and the radioisotope alpharadin. With these developments, the management of patients with CRPC is changing. In this Review, we discuss these promising therapies along with other novel agents that are demonstrating early signs of activity in CRPC. We propose a treatment pathway for patients with CRPC and consider strategies to optimize the use of these agents, including the incorporation of predictive and intermediate end point biomarkers, such as circulating tumor cells.

Changing therapeutic paradigms in castrate-resistant prostate cancer

Prostate cancer is the most common cancer, and the second leading cause of death from cancer, in males in most Western countries. Advanced prostate cancer is initially sensitive to androgen deprivation therapy, but usually progresses to the castration-resistant state. There is now incontrovertible evidence that castration-resistant prostate cancer (CRPC) remains hormone driven, with intratumoral steroid synthesis fueling tumor growth. Several novel agents targeted androgen receptor signaling are currently being evaluated including abiraterone and MDV3100. Recent results of the phase III trial of abiraterone acetate in post-docetaxel patients has shown an overall survival benefit in advanced CRPC. This new treatment is likely to become a new standard of care for patients with metastatic CRPC.

Abiraterone and increased survival in metastatic prostate cancer

BACKGROUND

Biosynthesis of extragonadal androgen may contribute to the progression of castration-resistant prostate cancer. We evaluated whether abiraterone acetate, an inhibitor of androgen biosynthesis, prolongs overall survival among patients with metastatic castration-resistant prostate cancer who have received chemotherapy.

METHODS

We randomly assigned, in a 2:1 ratio, 1195 patients who had previously received docetaxel to receive 5 mg of prednisone twice daily with either 1000 mg of abiraterone acetate (797 patients) or placebo (398 patients). The primary end point was overall survival. The secondary end points included time to prostate-specific antigen (PSA) progression (elevation in the PSA level according to prespecified criteria), progression-free survival according to radiologic findings based on prespecified criteria, and the PSA response rate.

RESULTS

After a median follow-up of 12.8 months, overall survival was longer in the abiraterone acetate-prednisone group than in the placebo-prednisone group (14.8 months vs. 10.9 months; hazard ratio, 0.65; 95% confidence interval, 0.54 to 0.77; P<0.001). Data were unblinded at the interim analysis, since these results exceeded the preplanned criteria for study termination. All secondary end points, including time to PSA progression (10.2 vs. 6.6 months; P<0.001), progression-free survival (5.6 months vs. 3.6 months; P<0.001), and PSA response rate (29% vs. 6%, P<0.001), favored the treatment group. Mineralocorticoid-related adverse events, including fluid retention, hypertension, and hypokalemia, were more frequently reported in the abiraterone acetate-prednisone group than in the placebo-prednisone group.

CONCLUSIONS

The inhibition of androgen biosynthesis by abiraterone acetate prolonged overall survival among patients with metastatic castration-resistant prostate cancer who previously received chemotherapy. (Funded by Cougar Biotechnology; COU-AA-301 ClinicalTrials.gov number, NCT00638690.).

Clinical and molecular determinants of survival in pancreatic cancer patients treated with second-line chemotherapy: results of an Italian/Swiss multicenter survey

BACKGROUND

Increased knowledge about the treatment of pancreatic cancer has influenced the management of locally advanced and metastatic disease. Nonetheless, prognosis remains dismal (24%, 1-year survival). The impact on overall survival (OS) of second-line therapy has not been clarified and the use of platinum salts and/or fluoropyrimidines is hotly debated. It is the hope that future treatment can be tailored to predict chemosensitivity in order to improve outcomes in patients with locally advanced and metastatic pancreatic cancer. Since DNA-damaging agents could be one therapeutic option, a retrospective multicenter study was performed to evaluate the efficacy of salvage treatment with the hypothesis that levels of the DNA repair gene excision repair cross complementing 1 (ERCC1) could influence OS.

PATIENTS AND METHODS

In a population of 160 patients treated with fluoropyrimidine-based second-line chemotherapy, expression levels of ERCC1 were determined by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). In 108 patients with locally advanced and metastatic pancreatic cancer treated with either fluoropyrimidines and platinum salts (group A=58) or fluoropyrimidines alone (group B=50), ERCC1 levels were correlated with OS, time to progression and response to chemotherapy.

RESULTS

Median survival was significantly higher in group A with low ERCC1 levels [11.9 versus 9.9 months; p ≤ 0.05] (median follow-up 24 months). Moreover in the same group, a trend towards longer time to progression was observed. No differences in OS were observed when ERCC1 was studied (low versus high) in patients not treated with platinum salts. On multivariate analysis of pretreatment prognostic factors, ERCC1 emerged as an independent predictive factor for OS.

CONCLUSION

The results of this study indicate that ERCC1 may predict survival in pancreatic cancer patients treated by platinum and fluoropyrimidine as second-line chemotherapy.

Horizon scanning for novel therapeutics for the treatment of prostate cancer

IMPORTANCE OF THE FIELD

Treatment options for patients with advanced prostate cancer (PCa) remain limited. Improved understanding of the underlying molecular drivers of prostate cancer pathogenesis, progression and resistance development has provided the fundamental basis for rational targeted drug design.

AREAS COVERED IN THIS REVIEW

This review will discuss the most recent developments in the field of prostate cancer therapies including key findings such as the identification of ETS gene rearrangements, the dissection of prostate cancer molecular heterogeneity and the discovery that castration-resistant prostate cancer (CRPC) remains androgen-driven despite the androgen-depleted milieu, thus making androgen receptor signaling a continued focus of molecularly targeted treatments. A multitude of new molecularly targeted agents are in clinical development and are highly likely to change the current treatment paradigm.

WHAT THE READER WILL GAIN

This review will outline the current clinical development of molecular targeted treatments in CRPC.

TAKE HOME MESSAGE

Unraveling the complex molecular biology that underpins this heterogeneous disease may pave the way to personalized therapy with a wide range of rationally targeted agents and combination treatments. In conclusion, we can predict that the rational clinical development of new targeted drugs will improve the outcome of men with prostate cancer in the years ahead.

Phase II dose escalation study of sorafenib in patients with metastatic renal cell carcinoma (mRCC) who have had prior treatment with VEGFR-TKI antiangiogenic treatment

e16027

Background: Sorafenib is an orally active multikinase inhibitor (Raf kinase, VEGFR 1, 2, 3 and PDGFR inhibitor) for the treatment of advanced RCC. The purpose of this study was to assess the efficacy and toxicity of Sorafenib in mRCC patients (pts) previously treated with an anti-angiogenic VEGFR-TKI using escalating dose levels. Methods: Pts with mRCC, PS 0–2 and adequate organ function were eligible. Pts received Sorafenib 400 mg/BID/continuously in 4-wk cycles. Pts with no progressive disease (evaluated at 12 weeks) continued to receive Sorafenib at the standard dose, while progressive pts received an increasing dose (600 mg BID) with early disease restaging after 4 weeks. Pts who progressed at 600 mg BID were taken off study. Efficacy was assessed by RECIST criteria. Results: 18 pts were entered; baseline characteristics: PS 0–1: 94%; median age 62 years (41–82); nephrectomy: 100%; surgery for metastatic disease: 28%, clear-cell 78%, papillary-cell 16%, sarcomatoid 6%.≥ 2 metastatic sites: 84%. 10 pts were refractory to cytokine treatment and all progressed or experienced unacceptable toxicity after anti-angiogenic VEGFR-TKI treatment, Sunitinib (13 pts) or Pazopanib (5 pts). Median number of cycles was 7.5 (1–16). Overall, 72% of pts had disease control without significant correlations between response to prior therapy and hypertension. 14 pts had progression free survival (PFS) of 4.3 months (mos). 4 pts are still in treatment with a median PFS > 8 mos. Of 6 pts in which the dose was escalated, 3 benefitted with a PFS of > 3 mos. The most common toxicity (NCIC 3.0, all pts) was grade (g) ≥ 1 diarrhea in 10 pts, g2–3 hand-foot syndrome in 7 pts and g-3 mucositis in 1 pt. Other hematological and non-hematological toxicities were g1 with a frequency < 15%. Conclusions: Sorafenib at doses of 400–600 mg/BID/continuosly results in acceptable and well tolerated salvage treatment after VEGFR-TKI failure. In progressive patients, treatment with a higher dose could be a valid option. Final and mature data will be presented in combination with translational research evaluating biological characteristics on tissue and blood.

No significant financial relationships to disclose.

Dose finding study of the combination of satraplatin and gemcitabine in patients with advanced solid tumors

e13534

Background: The potential advantage of combining satraplatin (S) a novel oral platinum with Gem is attractive. MTD and DLT of combination S and Gem in patients (pts) with advanced solid tumors was evaluated. Methods: Cohorts of 3–6 pts (modified Fibonacci) received escalating doses of i.v. Gem on days (d) 1, 8 and 15 Q 28 d followed by oral S on d 1–5. Seventeen pts with metastatic solid tumors were separated into 2 groups: A) Pts that had progressed following cytotoxic therapy and B) Pts who had received no prior chemotherapy. Starting dose was Gem 800 mg in both groups, S 40 mg and 60 mg for A and B respectively. Results: Group A. 6 previously treated pts with 1 or 2 regimens (3 prostate, 1 hepatocarcinoma, 1 bladder and 1 thymic ca) received 25 cycles, median 2 (2–12). 2 DLTs (G3 transaminases) were observed in 6 pts treated at level 1. Other G3 major toxicities were: thrombocytopenia (1 pt) and diarrhea (1 pt). 2 pts had PSA declines, with TTP of 630 days in 1 of them. Group B. 11 pts with no prior chemotherapy (4 hepatocarcinoma, 4 pancreas, 1 renal, 1 unknown origin and 1 gallbladder), received 38 cycles, median 2 (1–12). 1 DLT (G3 diarrhea) was observed in 8 pts treated at level 1 (2 not evaluable; received Gem d1 only), DLT (G3 thrombocytopenia) was observed in 3 pts treated at level 2 (Gem 1000, S 60). Other G3 toxicities were: thrombocytopenia (3 pts) and neutropenia (3 pts). 1 CR (pancreas) and 1 PR (gallbladder) were observed. Gem d8 or d15 was omitted in 11 of 17 pts during the 1st cycle. Conclusions: In this study the combination of S and Gem showed a clinically acceptable toxicity profile with promising antitumor activity. However, since in cycle 1, it was not possible to administer Gem on both d8 and d15 on 11 occasions, a 2nd study was initiated with S d1–3 and Gem d1 and 8 given on a Q 21 d schedule. Sponsored by GPC Biotech

No significant financial relationships to disclose.