Adjuvant Pazopanib Versus Placebo After Nephrectomy in Patients With Localized or Locally Advanced Renal Cell Carcinoma: Final Overall Survival Analysis of the Phase 3 PROTECT Trial

Most studies indicate no benefit of adjuvant therapy with VEGFR tyrosine kinase inhibitors in advanced renal cell carcinoma (RCC). PROTECT (NCT01235962) was a randomized, double-blind, placebo-controlled phase 3 study to evaluate adjuvant pazopanib in patients with locally advanced RCC at high risk of relapse after nephrectomy (pazopanib, n = 769; placebo, n = 769). The results of the primary analysis showed no difference in disease-free survival between pazopanib 600 mg and placebo. Here we report the final overall survival (OS) analysis (median follow-up: pazopanib, 76 mo, interquartile range [IQR] 66-84; placebo, 77 mo, IQR 69-85). There was no significant difference in OS between the pazopanib and placebo arms (hazard ratio 1.0, 95% confidence interval 0.80-1.26; nominal p > 0.9). OS was worse for patients with T4 disease compared to those with less advanced disease and was better for patients with body mass index (BMI) ≥30 kg/m² compared to those with lower BMI. OS was significantly better for patients who remained diseasefree at 2 yr after treatment compared with those who relapsed within 2 yr. These findings are consistent with the primary outcomes from PROTECT, indicating that adjuvant pazopanib does not confer a benefit in terms of OS for patients following resection of locally advanced RCC. PATIENT SUMMARY: In the randomized, double-blind, placebo-controlled phase 3 PROTECT study, overall survival was similar for patients with locally advanced renal cell carcinoma (RCC) at high risk of relapse after nephrectomy who received adjuvant therapy with pazopanib or placebo. Pazopanib is not recommended as adjuvant therapy following resection of locally advanced RCC. This trial is registered at Clinicaltrials.gov as NCT01235962.

Molecular Subsets in Renal Cancer Determine Outcome to Checkpoint and Angiogenesis Blockade

Integrated multi-omics evaluation of 823 tumors from advanced renal cell carcinoma (RCC) patients identifies molecular subsets associated with differential clinical outcomes to angiogenesis blockade alone or with a checkpoint inhibitor. Unsupervised transcriptomic analysis reveals seven molecular subsets with distinct angiogenesis, immune, cell-cycle, metabolism, and stromal programs. While sunitinib and atezolizumab + bevacizumab are effective in subsets with high angiogenesis, atezolizumab + bevacizumab improves clinical benefit in tumors with high T-effector and/or cell-cycle transcription. Somatic mutations in PBRM1 and KDM5C associate with high angiogenesis and AMPK/fatty acid oxidation gene expression, while CDKN2A/B and TP53 alterations associate with increased cell-cycle and anabolic metabolism. Sarcomatoid tumors exhibit lower prevalence of PBRM1 mutations and angiogenesis markers, frequent CDKN2A/B alterations, and increased PD-L1 expression. These findings can be applied to molecularly stratify patients, explain improved outcomes of sarcomatoid tumors to checkpoint blockade versus antiangiogenics alone, and develop personalized therapies in RCC and other indications.

Impact of COVID-19 pandemic on treatment patterns in metastatic clear cell renal cell carcinoma

BACKGROUND

The coronavirus pandemic has provoked discussions among healthcare providers how to manage cancer patients when faced with the threat of severe acute respiratory syndrome related coronavirus 2 (SARS-CoV-2) infection. Immune checkpoint inhibitor (ICI) containing regimens are standard of care in the majority of metastatic clear cell renal cell carcinoma (mccRCC) patients. It remains unclear whether therapies should be modified in response to the COVID-19 pandemic.

METHODS

We performed an online survey among physicians involved in the treatment of mccRCC, and 41 experts responded. Questions focused on criteria relevant for treatment decision outside the pandemic and the modifications of systemic therapy during COVID-19.

FINDINGS

For the majority of experts (73%), the combination of International metastatic renal cell carcinoma Database Consortium (IMDC) risk category and patient fitness are two important factors for decision-making. The main treatment choice in fit, favourable risk patients outside the pandemic is pembrolizumab/axitinib for 53%, avelumab/axitinib, sunitinib or pazopanib for 13% of experts each. During the pandemic, ICI-containing regimens are chosen less often in favour of a tyrosine kinase inhibitors (TKI) monotherapy, mainly sunitinib or pazopanib (35%).In fit, intermediate/poor-risk patients outside the pandemic, over 80% of experts choose ipilimumab/nivolumab, in contrast to only 41% of physicians during COVID-19, instead more TKI monotherapies are given. In patients responding to established therapies with ICI/ICI or ICI/TKI combinations, most participants modify treatment regimen by extending cycle length, holding one ICI or even both.

CONCLUSION

mccRCC treatment modifications in light of the coronavirus pandemic are variable, with a shift from ICI/ICI to ICI/TKI or TKI monotherapy.

Pancreatic tropism of metastatic renal cell carcinoma

Renal cell carcinoma (RCC) is characterized by a particularly broad metastatic swath, and, enigmatically, when the pancreas is a destination, the disease is associated with improved survival. Intrigued by this observation, we sought to characterize the clinical behavior, therapeutic implications, and underlying biology. While pancreatic metastases (PM) are infrequent, we identified 31 patients across 2 institutional cohorts and show that improved survival is independent of established prognostic variables, that these tumors are exquisitely sensitive to antiangiogenic agents and resistant to immune checkpoint inhibitors (ICIs), and that they are characterized by a distinctive biology. Primary tumors of patients with PM exhibited frequent PBRM1 mutations, 3p loss, and 5q amplification, along with a lower frequency of aggressive features such as BAP1 mutations and loss of 9p, 14q, and 4q. Gene expression analyses revealed constrained evolution with remarkable uniformity, reduced effector T cell gene signatures, and increased angiogenesis. Similar findings were observed histopathologically. Thus, RCC metastatic to the pancreas is characterized by indolent biology, heightened angiogenesis, and an uninflamed stroma, likely underlying its good prognosis, sensitivity to antiangiogenic therapies, and refractoriness to ICI. These data suggest that metastatic organotropism may be an indicator of a particular biology with prognostic and treatment implications for patients.

Deep androgen receptor suppression in prostate cancer exploits sexually dimorphic renal expression for systemic glucocorticoid exposure

BACKGROUND

Enzalutamide and apalutamide are potent next-generation androgen receptor (AR) antagonists used in metastatic and non-metastatic prostate cancer. Metabolic, hormonal and immunologic effects of deep AR suppression are unknown. We hypothesized that enzalutamide and apalutamide suppress 11β-hydroxysteroid dehydrogenase-2 (11β-HSD2), which normally converts cortisol to cortisone, leading to elevated cortisol concentrations, increased ratio of active to inactive glucocorticoids and possibly suboptimal response to immunotherapy. On-treatment glucocorticoid changes might serve as an indicator of active glucocorticoid exposure and resultant adverse consequences.

PATIENTS AND METHODS

Human kidney tissues were stained for AR and 11β-HSD2 expression. Patients in three trials [neoadjuvant apalutamide plus leuprolide, enzalutamide ± PROSTVAC (recombinant poxvirus prostate-specific antigen vaccine) for metastatic castration-resistant prostate cancer (CRPC) and enzalutamide ± PROSTVAC for non-metastatic castration-sensitive prostate cancer] were analyzed for cortisol and its metabolites using liquid chromatography-mass spectrometry (LC-MS/MS). Progression-free survival was determined in the metastatic CRPC study of enzalutamide ± PROSTVAC for those with glucocorticoid changes above and below the median.

RESULTS

Concurrent AR and 11β-HSD2 expression occurs only in the kidneys of men. A statistically significant rise in cortisol concentration, cortisol/cortisone ratio and tetrahydrocortisol/tetrahydrocortisone ratio with AR antagonist treatment occurred uniformly across all three trials. In the trial of enzalutamide ± PROSTVAC for metastatic CRPC, high cortisol/cortisone ratio in the enzalutamide arm was associated with significantly improved progression-free survival. However, in the enzalutamide + PROSTVAC arm, the opposite trend was observed.

CONCLUSION

Enzalutamide and apalutamide treatment toggles renal 11β-HSD2 and significantly increases indicators of and exposure to biologically active glucocorticoids, which is associated with clinical outcomes.

Descriptive comparison of hospital formulary decisions with published oncology valuation methods

INTRODUCTION

As cost of cancer therapy continues to increase, several organizations have developed rubrics to ascertain treatment. No studies have evaluated these methods for hospital formulary decision-making. We applied different value measurement tools to formulary decisions from one hospital system to assess their operational utility.

METHODS

We evaluated four value systems: National Comprehensive Cancer Network Evidence Blocks, DrugAbacus drug pricing, European Society for Medical Oncology clinical benefit scale, and the American Society of Clinical Oncology net health benefit. Each value score or cost was assessed against our hospital formulary requests between 2012 and 2016. Formulary requests accepted and rejected were compared with respect to their relative numbers of National Comprehensive Cancer Network blocks, difference between DrugAbacus and actual cost, and European Society for Medical Oncology and American Society of Clinical Oncology scores.

RESULTS

Twenty-two chemotherapy requests were included, with 20 approvals and 2 rejections. No correlation was observed between number of evidence blocks and formulary acceptance (p = 0.13). Most drugs had a higher actual price than the DrugAbacus suggested cost (p = 0.036). No significant differences were observed in European Society for Medical Oncology (p = 0.90) or American Society of Clinical Oncology (p = 0.70) scores between drugs that were accepted or rejected. When evaluating monthly cost per point of American Society of Clinical Oncology score, a numerical difference between groups was observed (median = $369.7 versus $1256.8 per point, p = 0.61).

CONCLUSIONS

Existing oncology value assessment systems only variably inform hospital formulary decisions. The American Society of Clinical Oncology net health benefit score deserves further study as a method to systematically quantify the clinical safety and efficacy of formulary medication addition relative to cost.

Comparative Effectiveness of Tumor Response Assessment Methods: Standard of Care Versus Computer-Assisted Response Evaluation

PURPOSE

To compare the effectiveness of metastatic tumor response evaluation with computed tomography using computer-assisted versus manual methods.

MATERIALS AND METHODS

In this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study, 11 readers from 10 different institutions independently categorized tumor response according to three different therapeutic response criteria by using paired baseline and initial post-therapy computed tomography studies from 20 randomly selected patients with metastatic renal cell carcinoma who were treated with sunitinib as part of a completed phase III multi-institutional study. Images were evaluated with a manual tumor response evaluation method (standard of care) and with computer-assisted response evaluation (CARE) that included stepwise guidance, interactive error identification and correction methods, automated tumor metric extraction, calculations, response categorization, and data and image archiving. A crossover design, patient randomization, and 2-week washout period were used to reduce recall bias. Comparative effectiveness metrics included error rate and mean patient evaluation time.

RESULTS

The standard-of-care method, on average, was associated with one or more errors in 30.5% (6.1 of 20) of patients, whereas CARE had a 0.0% (0.0 of 20) error rate ( P < .001). The most common errors were related to data transfer and arithmetic calculation. In patients with errors, the median number of error types was 1 (range, 1 to 3). Mean patient evaluation time with CARE was twice as fast as the standard-of-care method (6.4 minutes v 13.1 minutes; P < .001).

CONCLUSION

CARE reduced errors and time of evaluation, which indicated better overall effectiveness than manual tumor response evaluation methods that are the current standard of care.

Abstract 2505: Comprehensive molecular and genomic characterization of pancreatic tropism in metastatic renal cell carcinoma

Introduction & Objectives: Patients with metastatic renal cell carcinoma (mRCC) involving the pancreas have been shown to exhibit a relatively indolent course, yet the biologic explanation is unclear. We sought to characterize the genomic landscape of patients with mRCC harboring pancreatic metastases (PM) to identify molecular drivers of pancreatic tropism.

Materials & Methods: mRCC patients harboring PM from UTSW and Cleveland Clinic were identified. Clinicopathologic data and oncologic outcomes were analyzed. Samples were obtained from primary tumors, metastatic sites (including pancreatic or other distant metastases), and matched normal tissue. Whole exome (WES) and RNA sequencing of tumors was conducted. Patient-derived xenograft (PDX) models were generated from a subset of patients, and the engrafted tumors were analyzed.

Results: 31 mRCC patients with PM were included with 54 tumor samples derived from the primary tumor or thrombus (24), PM (21), or other metastatic sites (9). Median follow-up was 101 months. Clinicopathologic characteristics were similar between the two institutional cohorts, and all but one patient were favorable or intermediate IMDC risk. All patients had clear cell histology. 8 patients (26%) were metastatic at diagnosis, and median time to metastasis in the remaining patients was 74 months (IQR 32-120). Overall (OS) and cancer-specific (CSS) survival did not vary by IMDC risk group. OS was strikingly superior for mRCC patients with PM than a historic control of mRCC patients without PM (p&lt;0.001), even after controlling for IMDC risk score. Morphologically, tumors largely displayed low-grade acinar patterns. WES with matched normal tissue and RNAseq were completed with adequate quality for 48 and 30 samples, respectively. 14 PDX lines were generated, of which 5 (36%) engrafted stably (≥2 passages). WES from 2 tumorgraft specimens revealed preservation of specific mutations in the corresponding human samples.

Conclusions: mRCC patients with PM exhibit remarkably favorable survival outcomes. The relatively indolent biology of these tumors is reflected histologically and genomically and can be recapitulated in PDX models. Understanding tumor heterogeneity may help refine prognostic models for mRCC and hold implications for improved personalization of therapy.

Citation Format: Nirmish Singla, Jacob Choi, Oreoluwa Onabolu, Layton Woolford, Christina Stevens, Vanina Tcheuyap, Tiffani McKenzie, Zhiqun Xie, Tao Wang, Renee McKay, Alana Christie, Payal Kapur, Brian Rini, James Brugarolas. Comprehensive molecular and genomic characterization of pancreatic tropism in metastatic renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2505.

Robotic partial nephrectomy after pazopanib treatment in a solitary kidney with segmental vein thrombosis

OBJECTIVE

To demonstrate our surgical technique of robotic partial nephrectomy (RPN) in a patient with a solitary kidney who received neoadjuvant Pazopanib, highlighting the multidisciplinary approach.

MATERIALS AND METHODS

In our video, we present the case of 77-year-old male, Caucasian with 6.6cm left renal neoplasm in a solitary kidney. An initial percutaneous biopsy from the mass revealed clear cell RCC ISUP 2. After multidisciplinary tumor board meeting, Pazopanib (800mg once daily) was administered for 8 weeks with repeat imaging at completion of therapy. Post-TKI image study was compared with the pre-TKI CT using the Morphology, Attenuation, Size, and Structure criteria showing a favorable response to the treatment. Thereafter, a RPN was planned3. Perioperative surgical outcomes are presented.

RESULTS

Operative time was 224 minutes with a cold ischemia time of 53 minutes. Estimated blood loss was 800ml and the length of hospital stay was 4 days. Pathology demonstrated a specimen of 7.6cm with a tumor size of 6.5cm consistent with clear cell renal carcinoma ISUP 3 with a TNM staging pT1b Nx. Postoperative GFR was maintained at 24 ml / min compared to the preoperative value of 33ml / min.

CONCLUSIONS

A multidisciplinary approach is effective for patients in whom nephron preservation is critical, providing na opportunity to select those that may benefi t from TKI therapy. Pazopanib may allow for PN in a highly selective subgroup of patients who would otherwise require radical nephrectomy. Prospective data will be necessary before this strategy can be disseminated into clinical practice. Available at: http://www.intbrazjurol.com.br/video-section/20180240_Garisto_et_al.

Avelumab plus Axitinib versus Sunitinib for Advanced Renal-Cell Carcinoma

BACKGROUND

In a single-group, phase 1b trial, avelumab plus axitinib resulted in objective responses in patients with advanced renal-cell carcinoma. This phase 3 trial involving previously untreated patients with advanced renal-cell carcinoma compared avelumab plus axitinib with the standard-of-care sunitinib.

METHODS

We randomly assigned patients in a 1:1 ratio to receive avelumab (10 mg per kilogram of body weight) intravenously every 2 weeks plus axitinib (5 mg) orally twice daily or sunitinib (50 mg) orally once daily for 4 weeks (6-week cycle). The two independent primary end points were progression-free survival and overall survival among patients with programmed death ligand 1 (PD-L1)-positive tumors. A key secondary end point was progression-free survival in the overall population; other end points included objective response and safety.

RESULTS

A total of 886 patients were assigned to receive avelumab plus axitinib (442 patients) or sunitinib (444 patients). Among the 560 patients with PD-L1-positive tumors (63.2%), the median progression-free survival was 13.8 months with avelumab plus axitinib, as compared with 7.2 months with sunitinib (hazard ratio for disease progression or death, 0.61; 95% confidence interval [CI], 0.47 to 0.79; P<0.001); in the overall population, the median progression-free survival was 13.8 months, as compared with 8.4 months (hazard ratio, 0.69; 95% CI, 0.56 to 0.84; P<0.001). Among the patients with PD-L1-positive tumors, the objective response rate was 55.2% with avelumab plus axitinib and 25.5% with sunitinib; at a median follow-up for overall survival of 11.6 months and 10.7 months in the two groups, 37 patients and 44 patients had died, respectively. Adverse events during treatment occurred in 99.5% of patients in the avelumab-plus-axitinib group and in 99.3% of patients in the sunitinib group; these events were grade 3 or higher in 71.2% and 71.5% of the patients in the respective groups.

CONCLUSIONS

Progression-free survival was significantly longer with avelumab plus axitinib than with sunitinib among patients who received these agents as first-line treatment for advanced renal-cell carcinoma. (Funded by Pfizer and Merck [Darmstadt, Germany]; JAVELIN Renal 101 ClinicalTrials.gov number, NCT02684006.).

Overall survival and response to radiation and targeted therapies among patients with renal cell carcinoma brain metastases

OBJECTIVE

The object of this retrospective study was to investigate the impact of targeted therapies on overall survival (OS), distant intracranial failure, local failure, and radiation necrosis among patients treated with radiation therapy for renal cell carcinoma (RCC) metastases to the brain.

METHODS

All patients diagnosed with RCC brain metastasis (BM) between 1998 and 2015 at a single institution were included in this study. The primary outcome was OS, and secondary outcomes included local failure, distant intracranial failure, and radiation necrosis. The timing of targeted therapies was recorded. Multivariate Cox proportional-hazards regression was used to model OS, while multivariate competing-risks regression was used to model local failure, distant intracranial failure, and radiation necrosis, with death as a competing risk.

RESULTS

Three hundred seventy-six patients presented with 912 RCC BMs. Median OS was 9.7 months. Consistent with the previously validated diagnosis-specific graded prognostic assessment (DS-GPA) for RCC BM, Karnofsky Performance Status (KPS) and number of BMs were the only factors prognostic for OS. One hundred forty-seven patients (39%) received vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs). Median OS was significantly greater among patients receiving TKIs (16.8 vs 7.3 months, p < 0.001). Following multivariate analysis, KPS, number of metastases, and TKI use remained significantly associated with OS.The crude incidence of local failure was 14.9%, with a 12-month cumulative incidence of 13.4%. TKIs did not significantly decrease the 12-month cumulative incidence of local failure (11.4% vs 14.5%, p = 0.11). Following multivariate analysis, age, number of BMs, and lesion size remained associated with local failure. The 12-month cumulative incidence of radiation necrosis was 8.0%. Use of TKIs within 30 days of SRS was associated with a significantly increased 12-month cumulative incidence of radiation necrosis (10.9% vs 6.4%, p = 0.04).

CONCLUSIONS

Use of targeted therapies in patients with RCC BM treated with intracranial SRS was associated with improved OS. However, the use of TKIs within 30 days of SRS increases the rate of radiation necrosis without improving local control or reducing distant intracranial failure. Prospective studies are warranted to determine the optimal timing to reduce the rate of necrosis without detracting from survival.

Association of PD-L1, PD-L2, and Immune Response Markers in Matched Renal Clear Cell Carcinoma Primary and Metastatic Tissue Specimens

Objectives

Immune checkpoint therapy has been promising in renal cell carcinoma, but no validated clinically relevant biomarkers exist. Metastatic deposits may have discordant biomarker expression.

Methods

Fifty matched pairs of primary and metastatic kidney tumors were evaluated via immunohistochemistry for immune checkpoint proteins PD-1, PD-L1, and PD-L2 and the T-cell and macrophage surface markers CD3, FOXP3, and CD163. Semiquantitative scores incorporating prevalence of both tumor and nontumor labeling were compared between metastatic and primary kidney tumor specimens.

Results

A large minority of patients had discordant expression of PD-1 (31.2%), PD-L1 (22.5%), or PD-L2 (21.5%) between primary and metastatic sites. The expression of the novel marker PD-L2 correlated with both PD-1 (r = 0.47, P = .02) and PD-L1 (r = 0.67, P < .001) in metastatic deposits.

Conclusions

This study demonstrates that renal clear cell carcinoma primary tumors and metastatic deposits have some discordance in the expression of PD-L1, PD-1, and PD-L2.

Novel Agents and Drug Development Needs in Advanced Clear Cell Renal Cancer

The treatment of metastatic clear cell renal cancer is changing rapidly, with the focus switching from vascular endothelial growth factor-targeted therapies to immune checkpoint inhibitors and novel combinations. Specifically, recent data with programmed death ligand inhibitors is revolutionizing the standard approach to metastatic renal cell carcinoma. However, there is speculation around a number of newer potentially therapeutic targets, such as indoleamine 2,3-dioxygenase, transforming growth factor-β, interleukin-10, and adenosine. In this article, we review novel treatments, promising combinations, and consideration in both trial design and clinical application of therapeutics that will influence practice in the future.

Cases from the irAE Tumor Board: A Multidisciplinary Approach to a Patient Treated with Immune Checkpoint Blockade Who Presented with a New Rash

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment paradigms for a broad spectrum of malignancies. Because immune checkpoint inhibitors rely on immune reactivation to eliminate cancer cells, they can also lead to the loss of immune tolerance and result in a wide range of phenomena called immune-related adverse events (irAEs). At our institution, the management of irAEs is based on multidisciplinary input obtained at an irAE tumor board that facilitates expedited opinions from various specialties and allows for a more uniform approach to these patients. In this article, we describe a case of a patient with metastatic urothelial carcinoma who developed a maculopapular rash while being treated with a programmed death-ligand 1 inhibitor. We then describe the approach to management of dermatologic toxicities with ICIs based on the discussion at our irAE Tumor Board. KEY POINTS: Innocuous symptoms such as pruritis or a maculopapular rash may herald potentially fatal severe cutaneous adverse reactions (SCARs); therefore, close attention must be paid to the symptoms, history, and physical examination of all patients.Consultation with dermatology should be sought for patients with grade 3 or 4 toxicity or SCARs and prior to resumption of immune checkpoint inhibitors for patients with grade 3 or higher toxicity.A multidisciplinary immune-related adverse events (irAE) tumor board can facilitate timely input and expertise from various specialties, thereby ensuring a streamlined approach to management of irAEs.

HSD3B1(1245A>C) variant regulates dueling abiraterone metabolite effects in prostate cancer

BACKGROUND

A common germline variant in HSD3B1(1245A>C) encodes for a hyperactive 3β-hydroxysteroid dehydrogenase 1 (3βHSD1) missense that increases metabolic flux from extragonadal precursor steroids to DHT synthesis in prostate cancer. Enabling of extragonadal DHT synthesis by HSD3B1(1245C) predicts for more rapid clinical resistance to castration and sensitivity to extragonadal androgen synthesis inhibition. HSD3B1(1245C) thus appears to define a subgroup of patients who benefit from blocking extragonadal androgens. However, abiraterone, which is administered to block extragonadal androgens, is a steroidal drug that is metabolized by 3βHSD1 to multiple steroidal metabolites, including 3-keto-5α-abiraterone, which stimulates the androgen receptor. Our objective was to determine if HSD3B1(1245C) inheritance is associated with increased 3-keto-5α-abiraterone synthesis in patients.

METHODS

First, we characterized the pharmacokinetics of 7 steroidal abiraterone metabolites in 15 healthy volunteers. Second, we determined the association between serum 3-keto-5α-abiraterone levels and HSD3B1 genotype in 30 patients treated with abiraterone acetate (AA) after correcting for the determined pharmacokinetics.

RESULTS

Patients who inherit 0, 1, and 2 copies of HSD3B1(1245C) have a stepwise increase in normalized 3-keto-5α-abiraterone (0.04 ng/ml, 2.60 ng/ml, and 2.70 ng/ml, respectively; P = 0.002).

CONCLUSION

Increased generation of 3-keto-5α-abiraterone in patients with HSD3B1(1245C) might partially negate abiraterone benefits in these patients who are otherwise more likely to benefit from CYP17A1 inhibition.

FUNDING

Prostate Cancer Foundation Challenge Award, National Cancer Institute.

Next-generation sequencing (NGS) of cell-free circulating tumor DNA and tumor tissue in patients with advanced urothelial cancer: a pilot assessment of concordance

Background

Advances in cancer genome sequencing have led to the development of various next-generation sequencing (NGS) platforms. There is paucity of data regarding concordance of different NGS tests carried out in the same patient.

Methods

Here, we report a pilot analysis of 22 patients with metastatic urinary tract cancer and available NGS data from paired tumor tissue [FoundationOne (F1)] and cell-free circulating tumor DNA (ctDNA) [Guardant360 (G360)].

Results

The median time between the diagnosis of stage IV disease and the first genomic test was 23.5 days (0-767), after a median number of 0 (0-3) prior systemic lines of treatment of advanced disease. Most frequent genomic alterations (GA) were found in the genes TP53 (50.0%), TERT promoter (36.3%); ARID1 (29.5%); FGFR2/3 (20.5%), PIK3CA (20.5%) and ERBB2 (18.2%). While we identified GA in both tests, the overall concordance between the two platforms was only 16.4% (0%-50%), and 17.1% (0%-50%) for those patients (n = 6) with both tests conducted around the same time (median difference = 36 days). On the contrary, in the subgroup of patients (n = 5) with repeated NGS in ctDNA after a median of 1 systemic therapy between the two tests, average concordance was 55.5% (12.1%-100.0%). Tumor tissue mutational burden was significantly associated with number of GA in G360 report (P < 0.001), number of known GA (P = 0.009) and number of variants of unknown significance (VUS) in F1 report (P < 0.001), and with total number of GA (non-VUS and VUS) in F1 report (P < 0.001).

Conclusions

This study suggests a significant discordance between clinically available NGS panels in advanced urothelial cancer, even when collected around the same time. There is a need for better understanding of these two possibly complementary NGS platforms for better integration into clinical practice.

Drug Holiday in Metastatic Renal-Cell Carcinoma Patients Treated With Vascular Endothelial Growth Factor Receptor Inhibitors

INTRODUCTION

Tyrosine kinase inhibitor (TKI) therapy in metastatic renal-cell carcinoma (mRCC) is noncurative and may be associated with significant toxicities. Some patients may receive treatment breaks as a result of TKI-related adverse effects or planned drug holidays.

PATIENTS AND METHODS

In this retrospective study, mRCC patients who underwent drug holidays during TKI therapy at 2 different institutions were analyzed. A drug holiday was defined as a period of drug cessation for ≥ 3 months for reasons other than progressive disease.

RESULTS

Of the 112 patients, the median duration of the first drug holiday for the overall cohort was 16.8 months (95% confidence interval, 12.5-26.4), and 40 patients (36%) remain on the first drug holiday. Overall, patients received a median of 2 lines of treatment. Complete response before the initial drug holiday (n = 14) was associated with a longer surveillance period (P = .0004). The observed median survival of this cohort was 71.7 months (range, 1.3 to 93+ months).

CONCLUSION

Some selected mRCC patients with a favorable response to TKIs may be eligible for drug holidays. The cohort evaluated in this retrospective study represents a highly selected group of patients with indolent disease biology.

Abstract A100: Seamless phase I/II clinical trials in oncology: retrospective analysis of the last 7 years

Introduction: Drug development has evolved from the conventional sequence of three-phase clinical trial process to a seamless approach of adding cohorts to first-in-human trials to investigate both safety and efficacy in various cancers. In this retrospective study, we evaluated the prevalence of large early-phase studies in adult cancer patients; described the clinical characteristics, design, and statistical plan of these studies; and identified which investigational drugs using this seamless strategy were included in the accelerated approval program by the Food and Drug Administration (FDA).

Methods: All abstracts presented at the American Society of Clinical Oncology (ASCO) annual meetings from 2010 to 2017 were reviewed. Clinical studies conducted in the pediatric population as well as abstracts reporting trials in progress were excluded. Seamless clinical trials were defined as any phase I/II studies with a sample size of 100 or more patients. The Center for Drug Evaluation and Research (CDER) drug approvals report was used to access the list of drugs included in the accelerated approval program by FDA.

Results: We identified a total of 1786 early-phase trials enrolling more than 57,500 patients with malignant neoplasms. More frequently these studies included patients with advanced solid tumors (87%) and targeted therapy and immunotherapy agents were investigated in 64% and 15% of the cases, respectively. Of the 1786 trials, 51 were identified as seamless phase I/II with a sample size of 100 or more patients, representing only 3% of the total number of trials (n=1786) but 15% of the total number of patients (n=57,559). These seamless trials had a median number of 3 (1-13) expansion cohorts and a higher fraction (65%) were presented in the last 3 years (2014-2017), compared with 35% of the studies with results presented between 2010-2013. Fifty active investigational new drugs (67% targeted therapy, 18% immunotherapy, 10% antibody-drug conjugate, 2.0% chemotherapy, 3.9% other) were studied as single agents (53%) or in combination with other therapies (47%). Of the 51 identified large seamless phase I/II trials, only 29 (57%) studies had published results. Further, of these 29 studies, a planned statistical analysis for the calculation of the expansion cohorts’ sample-size was not available in 69% of the cases. The overall rate of significant (grade 3-4) adverse events was 49% (range, 0-100%), and at least one toxic death was reported in 5 of these studies. The pooled response rate (CR+PR) per study was 20% (range, 0.9-77). Considering the group of drugs studied in the 51-seamless phase I/II trials identified here, the FDA granted accelerated approval to 8 drugs and 1 other agent was given priority review.

Conclusions: Approximately two-thirds of the studies identified were presented after the year 2014, suggesting an increased use of the seamless approach. While the high rate of accelerated approvals granted by the FDA endorses the observed preliminary clinical benefit of these drugs, the absence of a prespecified statistical plan is a weakness of most of the published studies.

Citation Format: Pedro Barata, Brian Hobbs, Brian Rini, Channing Paller, Dan Normolle, Elizabeth Garrett-Mayer, Eric Rubin, Gary Rosner, Greg Pond, Jane Perlmutter, Lesley Seymour, Lillian Siu, Nolan Wages, Percy Ivy, Tatiana Prowell, Timothy Yap, David Hong. Seamless phase I/II clinical trials in oncology: retrospective analysis of the last 7 years [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A100.