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Featured researches published by Petros Grivas.


The Lancet | 2016

Atezolizumab in patients with locally advanced and metastatic urothelial carcinoma who have progressed following treatment with platinum-based chemotherapy: a single-arm, multicentre, phase 2 trial

Jonathan E. Rosenberg; Jean H. Hoffman-Censits; Thomas Powles; Michiel S. van der Heijden; Arjun Vasant Balar; Andrea Necchi; Nancy A. Dawson; Peter H. O'Donnell; Ani Balmanoukian; Yohann Loriot; Sandy Srinivas; M. Retz; Petros Grivas; Richard W. Joseph; Matthew D. Galsky; Mark T. Fleming; Daniel P. Petrylak; Jose Luis Perez-Gracia; Howard A. Burris; Daniel Castellano; Christina Canil; Joaquim Bellmunt; Dean F. Bajorin; Dorothee Nickles; Richard Bourgon; Garrett Michael Frampton; Na Cui; Sanjeev Mariathasan; Oyewale O. Abidoye; Gregg Fine

BACKGROUND Patients with metastatic urothelial carcinoma have few treatment options after failure of platinum-based chemotherapy. In this trial, we assessed treatment with atezolizumab, an engineered humanised immunoglobulin G1 monoclonal antibody that binds selectively to programmed death ligand 1 (PD-L1), in this patient population. METHODS For this multicentre, single-arm, two-cohort, phase 2 trial, patients (aged ≥18 years) with inoperable locally advanced or metastatic urothelial carcinoma whose disease had progressed after previous platinum-based chemotherapy were enrolled from 70 major academic medical centres and community oncology practices in Europe and North America. Key inclusion criteria for enrolment were Eastern Cooperative Oncology Group performance status of 0 or 1, measurable disease defined by Response Evaluation Criteria In Solid Tumors version 1.1 (RECIST v1.1), adequate haematological and end-organ function, and no autoimmune disease or active infections. Formalin-fixed paraffin-embedded tumour specimens with sufficient viable tumour content were needed from all patients before enrolment. Patients received treatment with intravenous atezolizumab (1200 mg, given every 3 weeks). PD-L1 expression on tumour-infiltrating immune cells (ICs) was assessed prospectively by immunohistochemistry. The co-primary endpoints were the independent review facility-assessed objective response rate according to RECIST v1.1 and the investigator-assessed objective response rate according to immune-modified RECIST, analysed by intention to treat. A hierarchical testing procedure was used to assess whether the objective response rate was significantly higher than the historical control rate of 10% at an α level of 0·05. This study is registered with ClinicalTrials.gov, number NCT02108652. FINDINGS Between May 13, 2014, and Nov 19, 2014, 486 patients were screened and 315 patients were enrolled into the study. Of these patients, 310 received atezolizumab treatment (five enrolled patients later did not meet eligibility criteria and were not dosed with study drug). The PD-L1 expression status on infiltrating immune cells (ICs) in the tumour microenvironment was defined by the percentage of PD-L1-positive immune cells: IC0 (<1%), IC1 (≥1% but <5%), and IC2/3 (≥5%). The primary analysis (data cutoff May 5, 2015) showed that compared with a historical control overall response rate of 10%, treatment with atezolizumab resulted in a significantly improved RECIST v1.1 objective response rate for each prespecified immune cell group (IC2/3: 27% [95% CI 19-37], p<0·0001; IC1/2/3: 18% [13-24], p=0·0004) and in all patients (15% [11-20], p=0·0058). With longer follow-up (data cutoff Sept 14, 2015), by independent review, objective response rates were 26% (95% CI 18-36) in the IC2/3 group, 18% (13-24) in the IC1/2/3 group, and 15% (11-19) overall in all 310 patients. With a median follow-up of 11·7 months (95% CI 11·4-12·2), ongoing responses were recorded in 38 (84%) of 45 responders. Exploratory analyses showed The Cancer Genome Atlas (TCGA) subtypes and mutation load to be independently predictive for response to atezolizumab. Grade 3-4 treatment-related adverse events, of which fatigue was the most common (five patients [2%]), occurred in 50 (16%) of 310 treated patients. Grade 3-4 immune-mediated adverse events occurred in 15 (5%) of 310 treated patients, with pneumonitis, increased aspartate aminotransferase, increased alanine aminotransferase, rash, and dyspnoea being the most common. No treatment-related deaths occurred during the study. INTERPRETATION Atezolizumab showed durable activity and good tolerability in this patient population. Increased levels of PD-L1 expression on immune cells were associated with increased response. This report is the first to show the association of TCGA subtypes with response to immune checkpoint inhibition and to show the importance of mutation load as a biomarker of response to this class of agents in advanced urothelial carcinoma. FUNDING F Hoffmann-La Roche Ltd.


Cancer | 2014

A randomized phase 2 trial of gemcitabine/cisplatin with or without cetuximab in patients with advanced urothelial carcinoma

Maha Hussain; Stephanie Daignault; Neeraj Agarwal; Petros Grivas; Arlene O. Siefker-Radtke; Igor Puzanov; Gary R. MacVicar; Ellis G. Levine; Sandy Srinivas; Przemyslaw Twardowski; Mario A. Eisenberger; David I. Quinn; Ulka N. Vaishampayan; Evan Y. Yu; Scott J. Dawsey; Kathleen C. Day; Mark L. Day; Mahmoud M. Al-Hawary; David C. Smith

Epidermal growth factor receptor overexpression is associated with poor outcomes in urothelial carcinoma (UC). Cetuximab (CTX) exhibited an antitumor effect in in vivo UC models. The efficacy of gemcitabine/cisplatin (GC) with or without CTX in patients with advanced UC was evaluated.


Cancer | 2014

Double-Blind, Randomized, Phase 2 Trial of Maintenance Sunitinib Versus Placebo After Response to Chemotherapy in Patients With Advanced Urothelial Carcinoma

Petros Grivas; Stephanie Daignault; Scott T. Tagawa; David M. Nanus; Walter M. Stadler; Robert Dreicer; Manish Kohli; Daniel P. Petrylak; David J. Vaughn; Kathryn Bylow; Steven G. Wong; Joseph L. Sottnik; Evan T. Keller; Mahmoud M. Al-Hawary; David C. Smith; Maha Hussain

Angiogenesis contributes to the progression of urothelial carcinoma (UC). In the current study, the authors investigated the role of maintenance sunitinib in patients with advanced UC.


Virchows Archiv | 2011

Expression of the ribonucleases Drosha, Dicer, and Ago2 in colorectal carcinomas

Dionysios J. Papachristou; Angeliki Korpetinou; Efstathia Giannopoulou; Anna G. Antonacopoulou; Helen Papadaki; Petros Grivas; Chrisoula D. Scopa; Haralabos P. Kalofonos

The pathogenesis of colorectal carcinoma (CRC) is a complex process that involves the recruitment of both genetic and epigenetic mechanisms. Recent studies underline the cardinal role of small, noncoding RNA molecules, called microRNAs (miRs), in the pathobiology of numerous physiological and pathological processes, including oncogenesis. MiR biogenesis and maturation is mainly regulated by the nuclear ribonuclease Drosha and the cytoplasmic ribonucleases Dicer and Ago2. In the present study, we investigated the expression and distribution of these molecules in three colon cancer cell lines and in human CRC samples. Drosha, Dicer, and Ago2 mRNA and protein expression was assessed with real-time PCR, western blotting, and immunofluorescence. Our experiments showed that Drosha, Dicer, and Ago2 were expressed in all the cell lines and in the majority of the CRC samples examined. The mRNA levels of Dicer were significantly augmented in stage III compared to stage II tumors. Our results suggest that Drosha, Dicer, and Ago2 are possibly implicated in CRC pathobiology and that Dicer might have a role in the progression of these tumors to advanced stages.


Urology | 2013

A Phase II Trial of Neoadjuvant nab-paclitaxel, Carboplatin, and Gemcitabine (ACaG) in Patients With Locally Advanced Carcinoma of the Bladder

Petros Grivas; Maha Hussain; Khaled S. Hafez; Stephanie Daignault-Newton; David P. Wood; Cheryl T. Lee; Alon Z. Weizer; James E. Montie; Brent K. Hollenbeck; Jeffrey S. Montgomery; Ajjai Alva; David C. Smith

OBJECTIVE To assess the activity of neoadjuvant nab-paclitaxel, carboplatin, gemcitabine (ACaG) followed by cystectomy in patients with muscle-invasive urothelial carcinoma of the bladder. METHODS Patients who were candidates for cystectomy received nab-paclitaxel 260 mg/m(2) on day 1, carboplatin area under the curve 5 on day 1, and gemcitabine 800 mg/m(2) on days 1 and 8, every 21 days for 3 cycles. The first 3 patients received nab-paclitaxel 100 mg/m(2) weekly and were not included in the efficacy analysis of evaluable patients. Efficacy was assessed by the percentage of patients with pathologic complete response (pT0) at cystectomy. Progression-free and overall survival was estimated using the Kaplan-Meier methods. RESULTS Of 29 patients enrolled, 26 received the planned 3 cycles with 82 cycles overall; doses were reduced in 16 patients. Of 29 patients, nearly all patients experienced grade 3-4 neutropenia; 17 patients (58.6%) required growth factor, and 16 patients (55.2%) experienced grade 3-4 thrombocytopenia; there was 1 toxicity-related death. Nonhematological toxicity was generally tolerable. Twenty-two of 26 patients were evaluable for the primary endpoint: 6 patients (27.3%, 95% confidence interval [CI] 10.7-50.2) had pT0, 6 pTis, 1 pT1, 54.5% of patients had no residual muscle-invasive disease (<pT2N0), and 81.8% had pN0 at cystectomy. By intent-to-treat (ITT) analysis, the pT0 rate was 27.6% (95% CI 12.7-47.2). CONCLUSION Neoadjuvant nab-paclitaxel, carboplatin, gemcitabine is feasible but grade 3-4 myelotoxicity is common. Although the regimen has activity, the pT0 rate is lower than those reported with cisplatin-based regimens and did not meet the predefined threshold to support further investigation. Taxane-based regimens remain investigational for neoadjuvant therapy of bladder cancer.


Trends in Molecular Medicine | 2011

Tackling transcription factors: challenges in antitumor therapy.

Petros Grivas; Hippokratis Kiaris; Athanasios G. Papavassiliou

New drugs that have recently received approval clinically justify targeting signal transduction enzymes (i.e. kinases and phosphatases) in the treatment of various cancers. Unfortunately, clinical responses are not always consistent with results from preclinical models. For example, the prognosis of patients with advanced solid tumors has largely remained unchanged. Redundancy and wide-ranging crosstalk between signaling pathways, as well as polymorphisms or mutations in targeted molecules, could partially account for such modest effects [1].


Journal of Clinical Oncology | 2017

A Phase II Study of Intermittent Sunitinib in Previously Untreated Patients With Metastatic Renal Cell Carcinoma

Moshe Chaim Ornstein; Laura S. Wood; Paul Elson; Kimberly D Allman; Jennifer Beach; Allison Martin; Beth Zanick; Petros Grivas; Tim Gilligan; Jorge A. Garcia; Brian I. Rini

Purpose Sunitinib is a standard initial therapy in metastatic renal cell carcinoma (mRCC), but chronic dosing requires balancing toxicity with clinical benefit. The feasibility and clinical outcome with intermittent sunitinib dosing in patients with mRCC was explored. Patients and Methods Patients with treatment-naïve, clear cell mRCC were treated with four cycles of sunitinib (50 mg once per day, 4 weeks of receiving treatment followed by 2 weeks of no treatment). Patients with a ≥ 10% reduction in tumor burden (TB) after four cycles had sunitinib held, with restaging scans performed every two cycles. Sunitinib was reinitiated for two cycles in those patients with an increase in TB by ≥ 10%, and again held with ≥ 10% TB reduction. This intermittent sunitinib dosing continued until Response Evaluation Criteria in Solid Tumors-defined disease progression while receiving sunitinib, or unacceptable toxicity occurred. The primary objective was feasibility, defined as the proportion of eligible patients who underwent intermittent therapy. Results Of 37 patients enrolled, 20 were eligible for intermittent therapy and all patients (100%) entered the intermittent phase. Patients were not eligible for intermittent sunitinib because of progressive disease (n = 13), toxicity (n = 1), or consent withdrawal (n = 3) before the end of cycle 4. The objective response rate was 46% after the first four cycles of therapy. The median increase in TB during the periods off sunitinib was 1.6 cm (range, -2.9 to 3.4 cm) compared with the TB immediately before stopping sunitinib. Most patients exhibited a stable sawtooth pattern of TB reduction while receiving sunitinib and TB increase while not receiving sunitinib. Median progression-free survival to date is 22.4 months (95% CI, 5.4 to 37.6 months) and median overall survival is 34.8 months (95% CI, 14.8 months to not applicable). Conclusion Periodic extended sunitinib treatment breaks are feasible and clinical efficacy does not seem to be compromised.


Clinical Genitourinary Cancer | 2017

Efficacy and Safety of Gemcitabine Plus Either Taxane or Carboplatin in the First-Line Setting of Metastatic Urothelial Carcinoma: A Systematic Review and Meta-Analysis.

Andrea Necchi; Gregory R. Pond; Daniele Raggi; Patrizia Giannatempo; Nicholas J. Vogelzang; Petros Grivas; Matthew D. Galsky; Joaquim Bellmunt; Guru Sonpavde

&NA; Although gemcitabine plus carboplatin (GCa) is the conventional first‐line chemotherapy for cisplatin‐ineligible metastatic urothelial carcinoma, its results are suboptimal. A meta‐analysis evaluated the results of gemcitabine with either carboplatin or a taxane (GT). Literature was searched for studies including GT (paclitaxel or docetaxel) and GCa. We pooled trial level data including response‐rate, progression‐free survival, overall survival (OS), and Grade 3 to 4 side effects. Trial characteristics and outcomes were univariably compared between GT and GCa. Those factors, which were recorded in > 12 trials, were analyzed. Multivariable regression models were used adjusting for Eastern Cooperative Oncology Group performance status 2 and the presence of visceral metastases. Each trial was weighted by its sample size. Twenty‐seven arms of trials totaling 1032 patients were selected, of which 13 contained GT (n = 484) and 14 GCa (n = 548). The percentage of patients with Eastern Cooperative Oncology Group performance status 2 was statistically significantly different between the 2 groups (median, 8.7% vs. 23.9%; P = .003). No efficacy outcome was statistically significantly different. Median OS was 13.2 months (range, 10‐15.8 months) for GT and 10 months (range, 3.3‐20 months) for GCa (P = .12). However, statistically significant increases in the frequency of Grade 3 to 4 anemia (P = .010) and thrombocytopenia (P = .010) for GCa, and neuropathy (P = .040) for GT were observed. No difference in OS according to treatment was found multivariably (P = .79). In this analysis, a similar response rate and survival and worse neurotoxicity were observed with GT compared with GCa, for which hematologic toxicity was more frequent. GT is an alternative to GCa for advanced cisplatin‐ineligible urothelial cancer.


Annals of Oncology | 2017

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

Pedro C. Barata; Vadim S. Koshkin; P. Funchain; Davendra Sohal; A. Pritchard; Stefan Klek; T. Adamowicz; Dharmesh Gopalakrishnan; Jorge A. Garcia; Brian I. Rini; Petros Grivas

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.


Critical Reviews in Oncology Hematology | 2013

Predicting response to hormonal therapy and survival in men with hormone sensitive metastatic prostate cancer

Petros Grivas; Diane M. Robins; Maha Hussain

Androgen deprivation is the cornerstone of the management of metastatic prostate cancer. Despite several decades of clinical experience with this therapy there are no standard predictive biomarkers for response. Although several candidate genetic, hormonal, inflammatory, biochemical, metabolic biomarkers have been suggested as potential predictors of response and outcome, none has been prospectively validated nor has proven clinical utility to date. There is significant heterogeneity in the depth and duration of hormonal response and in the natural history of advanced disease; therefore to better optimize/individualize therapy and for future development, identification of biomarkers is critical. This review summarizes the current data on the role of several candidate biomarkers that have been evaluated in the advanced/metastatic disease setting.

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Hamid Emamekhoo

University of Wisconsin-Madison

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Sumanta K. Pal

City of Hope National Medical Center

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