Clinician-to-clinician connectedness and access to gastric cancer surgery at National Cancer Institute-designated cancer centers.

BACKGROUND: For patients with gastric cancer, the pathway from primary care (PC) clinician to gastroenterologist to cancer specialist (medical oncologist or surgeons) is referral dependent. The impact of clinician connectedness on disparities in quality gastric cancer care, such as at National Cancer Institute-designated cancer centers (NCI-CC), remains underexplored. This study evaluated how clinician connectedness influences access to gastrectomy at NCI-CC. METHODS: Maryland's All-Payer Claims Database was used to evaluate 667 patients who underwent gastrectomy for cancer from 2013 to 2018. Two separate referral linkages, defined as ≥9 shared patients, were examined: (1) PC clinicians to gastroenterologists at NCI-CC and (2) gastroenterologists to cancer specialists at NCI-CC. Multiple logistic regression models determined associations between referral linkages and odds of undergoing gastrectomy at NCI-CC. RESULTS: Only 15% of gastrectomies were performed at NCI-CC. Patients of gastroenterologists with referral links to cancer specialists at NCI-CC were more likely to be <65 years, male, White, and privately insured. Every additional referral link between PC clinician and gastroenterologist at NCI-CC and between gastroenterologist and cancer specialist at NCI-CC increased the odds of gastrectomy at NCI-CC by 71% and 26%, respectively. Black patients had half the odds as White patients in receiving gastrectomy at NCI-CC; however, adjusting for covariates including clinician-to-clinician connectedness attenuated this observation. CONCLUSION: Patients of clinicians with low connectedness and Black patients are less likely to receive gastrectomy at NCI-CC. Enhancing clinician connectedness is necessary to address disparities in cancer care. These results are relevant to policy makers, clinicians, and patient advocates striving for health equity.

Patterns of Failure Following Preoperative Chemotherapy and Stereotactic Body Radiation Therapy and Resection for Patients with Borderline Resectable or Locally Advanced Pancreatic Cancer.

BACKGROUND: The role of neoadjuvant stereotactic body radiation therapy (SBRT) in the treatment of pancreatic adenocarcinoma (PDAC) is controversial and the optimal target volumes and dose-fractionation are unclear. The aim of this study is to report on treatment outcomes and patterns of failure of patients with borderline resectable (BL) or locally advanced (LA) pancreatic cancer following preoperative chemotherapy and SBRT. METHODS: We conducted a single-institution, retrospective study of patients with BL or LA PDAC. Patients received neoadjuvant chemotherapy and SBRT was prescribed to 30 Gy over 5 fractions to the pancreas planning tumor volume (PTV). A subset of patients received a simultaneous integrated boost to the high risk vascular PTV and/or elective nodal irradiation (ENI). Following neoadjuvant chemoradiation, all patients underwent subsequent resection. Overall survival (OS), progression-free survival (PFS), locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMPFS), and locoregional control (LRC) estimates were obtained using Kaplan-Meier analysis. RESULTS: Twenty-two patients with BL (18) or LA (4) PDAC were treated with neoadjuvant chemotherapy and SBRT followed by resection from 2011-2022. Following neoadjuvant treatment, 5 patients (23%) achieved a pathologic complete response (pCR) and 16 patients (73%) had R0 resection. At 24 months, there were no isolated locoregional recurrences (LRRs), 9 isolated distant recurrences (DRs), and 5 combined LRRs and DRs. Two LRRs were in-field, 2 LRRs were marginal, and 1 LRR was both in-field and marginal. 2-year median LRC, LRRFS, DMPFS, PFS, and OS were 77.3%, 45.5%, 31.8%, 31.8%, and 59.1%, respectively. For BL and LA cancers, 2-year LRC, DMPFS, and OS were 83% vs. 75%, (p = 0.423), 39% vs. 0% (p = 0.006), and 61% vs. 50% (p = 0.202), respectively. ENI was associated with improved LRC (p = 0.032) and LRRFS (p = 0.033). Borderline resectability (p = 0.018) and lower tumor grade (p = 0.027) were associated with improved DMPFS. CONCLUSIONS: Following preoperative chemotherapy and SBRT, locoregional failure outside of the target volume occurred in 3 of 5 recurrences; ENI was associated with improved LRC and LRRFS. Further studies are necessary to define the optimal techniques for preoperative radiation therapy.

Evolving applications of liquid biopsies in gastrointestinal cancers.

Liquid biopsy is a test that allows for the diagnosis and analysis of cancer by sampling cancer cells or byproducts present in biological fluids such as blood or urine. It has the potential to create a new paradigm in oncologic care, being a less invasive approach than conventional tissue biopsy. Liquid biopsy has multifaceted applications for longitudinal disease monitoring in terms of surveillance, treatment response, and identification of emerging resistance mechanisms. Multiple assays currently exist or are in development for detecting circulating tumor cells, DNA, RNA, exosomes, proteins, fragmentomic markers, and metabolomes. Here, we review the applications of liquid biopsy in gastrointestinal cancers, emphasizing its use in both perioperative and advanced settings. We also examine its role in screening, diagnostics, and other cancer-related scenarios.

Phase 1 Study of Hypofractionated Proton Beam Radiation Therapy in Adjuvant Pancreatic Cancer (PROTON-PANC).

PURPOSE: Despite improvement in systemic therapy, patients with pancreatic ductal adenocarcinoma (PDAC) frequently experience local recurrence. We sought to determine the safety of hypofractionated proton beam radiation therapy (PBT) during adjuvant chemotherapy. METHODS AND MATERIALS: Nine patients were enrolled in a single-institution phase 1 trial (NCT03885284) between 2019 and 2022. Patients had PDAC of the pancreatic head and underwent R0 or R1 resection and adjuvant modified FOLFIRINOX (mFFX) chemotherapy. The primary endpoint was to determine the dosing schedule of adjuvant PBT (5 Gy × 5 fractions) using limited treatment volumes given between cycles 6 and 7 of mFFX. Patients received PBT on days 15 to 19 in a 28-day cycle before starting cycle 7 (dose level 1, DL1) or on days 8 to 12 in a 21-day cycle before starting cycle 7 (DL2). RESULTS: The median patient age was 66 years (range, 52-78), and the follow-up time from mFFX initiation was 12.5 months (range, 6.2-37.4 months). No patients received preoperative therapy. Four had R1 resections and 5 had node-positive disease. Three patients were enrolled on DL1 and 6 patients on DL2. One dose-limiting toxicity (DLT) occurred at DL2 (prolonged grade 3 neutropenia resulting in discontinuation of mFFX after cycle 7). No other DLTs were observed. Four patients completed 12 cycles of mFFX (range, 7-12; median, 11). No patients have had local recurrence. Five of 9 patients had recurrence: 3 in the liver, 1 in the peritoneum, and 1 in the bone. Six patients are still alive, 4 of whom are recurrence-free. The median time to recurrence was 12 months (95% CI, 4 to not reached [NR]), and median overall survival was NR (95% CI, 6 to NR; 2-year survival rate, 57%). CONCLUSIONS: PBT integrated within adjuvant mFFX was well tolerated, and no local recurrence was observed. These findings warrant further exploration in a phase 2 trial.

Perioperative therapy landscape for locally advanced, resectable esophageal cancer: an updated literature review.

Background and Objective: The poor oncologic outcomes associated with esophageal cancer (EC) are primarily due to its presentation at an advanced stage and patient comorbidities. While multimodal therapy improves overall outcomes, there is a lack of uniform practice in terms of perioperative management, partly because this is a rapidly evolving field in a heterogeneous patient population. With numerous recent studies incorporating precision medicine with radiographic, pathologic, and genomic biomarkers and with emerging trials using targeted therapies, it is necessary for providers who care for these patients to be familiar with the current and evolving treatment standards to optimize patient outcomes. The objective of this paper is to perform an updated review of the main historical and recently emerging studies that impact the perioperative management of patients with locally advanced, upfront-resectable EC. Methods: We mined and reviewed PubMed and American Society of Clinical Oncology databases for pivotal works shaping the current perioperative treatment landscape in locally advanced EC. Key Content and Findings: EC are a vastly heterogeneous disease, and treatment options vary based on tumor anatomic location, histology, and patient comorbidities. Perioperative chemotherapy (CTX), chemoradiation (CRT), and, recently, immunotherapy have improved survival in patients with locally advanced disease. However, optimizing sequencing, de-escalating therapy, and incorporating novel targeted therapies in the perioperative setting are promising strategies that are under ongoing investigation to improve patient outcomes further. Conclusions: There is an ongoing need to identify predictive biomarkers and novel treatment strategies to personalize perioperative approaches and optimize outcomes of patients with EC.

Propagated Circulating Tumor Cells Uncover the Potential Role of NFκB, EMT, and TGFß Signaling Pathways and COP1 in Metastasis.

Circulating tumor cells (CTCs), a population of cancer cells that represent the seeds of metastatic nodules, are a promising model system for studying metastasis. However, the expansion of patient-derived CTCs ex vivo is challenging and dependent on the collection of high numbers of CTCs, which are ultra-rare. Here we report the development of a combined CTC and cultured CTC-derived xenograft (CDX) platform for expanding and studying patient-derived CTCs from metastatic colon, lung, and pancreatic cancers. The propagated CTCs yielded a highly aggressive population of cells that could be used to routinely and robustly establish primary tumors and metastatic lesions in CDXs. Differential gene analysis of the resultant CTC models emphasized a role for NF-κB, EMT, and TGFß signaling as pan-cancer signaling pathways involved in metastasis. Furthermore, metastatic CTCs were identified through a prospective five-gene signature (BCAR1, COL1A1, IGSF3, RRAD, and TFPI2). Whole-exome sequencing of CDX models and metastases further identified mutations in constitutive photomorphogenesis protein 1 (COP1) as a potential driver of metastasis. These findings illustrate the utility of the combined patient-derived CTC model and provide a glimpse of the promise of CTCs in identifying drivers of cancer metastasis.

Napabucasin plus nab-paclitaxel with gemcitabine versus nab-paclitaxel with gemcitabine in previously untreated metastatic pancreatic adenocarcinoma: an adaptive multicentre, randomised, open-label, phase 3, superiority trial.

Background: Compared with normal cells, tumour cells contain elevated levels of reactive oxygen species (ROS). Increased levels of the antioxidant protein NAD(P)H:quinone oxidoreductase 1 (NQO1) and phosphorylated signal transducer and activator of transcription 3 (pSTAT3) correlate negatively with the survival of patients with pancreatic cancer. Napabucasin is an investigational, orally administered ROS generator bioactivated by NQO1. Methods: In the open-label, phase 3 CanStem111P study (NCT02993731), adults with previously untreated metastatic pancreatic adenocarcinoma (mPDAC) were randomised (1:1) to napabucasin plus nab-paclitaxel with gemcitabine or nab-paclitaxel with gemcitabine alone. The primary endpoint was overall survival (OS). In exploratory analyses, OS was evaluated in the subgroup of patients with tumours positive for pSTAT3 (biomarker-positive). Findings: Between 30 January 2017 and 20 February 2019, a total of 1779 patients were screened across 165 study sites in Austria, Australia, Belgium, Canada, China, Czech Republic, France, Germany, Italy, Japan, Korea, Netherlands, Poland, Portugal, Russia, Singapore, Spain, Taiwan, Ukraine, and the US. Of the 565 and 569 patients randomised to the napabucasin and control treatment arms, respectively, 206 and 176 were biomarker-positive. Median (95% confidence interval [CI]) OS in the napabucasin and control treatment arms was 11.4 (10.5-12.2) and 11.7 (10.7-12.7) months, respectively (hazard ratio, 1.07; 95% CI, 0.93-1.23). Due to the lack of OS improvement in the napabucasin arm, CanStem111P was terminated due to futility. In the biomarker-positive subgroup, no difference between treatment arms was found for OS. Grade ≥3 adverse events were reported in 85.4% and 83.9% of napabucasin-treated and control-treated patients, respectively. The incidence of gastrointestinal-related grade ≥3 events was higher with napabucasin (diarrhoea: 11.6% vs 4.9%; abdominal pain: 10.0% vs 4.8%). Interpretation: Our findings suggested that although the addition of napabucasin to nab-paclitaxel with gemcitabine did not improve efficacy in patients with previously untreated mPDAC, the safety profile of napabucasin was consistent with previous reports. CanStem111P represents the largest cohort of patients with mPDAC administered nab-paclitaxel with gemcitabine in the clinical trial setting. Our data reinforce the value of nab-paclitaxel plus gemcitabine as a platform for novel therapeutics approaches in mPDAC. Funding: The Sumitomo Pharma Oncology, Inc.

Adjuvant nab-Paclitaxel + Gemcitabine in Resected Pancreatic Ductal Adenocarcinoma: Results From a Randomized, Open-Label, Phase III Trial.

PURPOSE: This randomized, open-label trial compared the efficacy and safety of adjuvant nab-paclitaxel + gemcitabine with those of gemcitabine for resected pancreatic ductal adenocarcinoma (ClinicalTrials.gov identifier: NCT01964430). METHODS: We assigned 866 treatment-naive patients with pancreatic ductal adenocarcinoma to nab-paclitaxel (125 mg/m2) + gemcitabine (1,000 mg/m2) or gemcitabine alone to one 30-40 infusion on days 1, 8, and 15 of six 28-day cycles. The primary end point was independently assessed disease-free survival (DFS). Additional end points included investigator-assessed DFS, overall survival (OS), and safety. RESULTS: Two hundred eighty-seven of 432 patients and 310 of 434 patients completed nab-paclitaxel + gemcitabine and gemcitabine treatment, respectively. At primary data cutoff (December 31, 2018; median follow-up, 38.5 [interquartile range [IQR], 33.8-43 months), the median independently assessed DFS was 19.4 (nab-paclitaxel + gemcitabine) versus 18.8 months (gemcitabine; hazard ratio [HR], 0.88; 95% CI, 0.729 to 1.063; P = .18). The median investigator-assessed DFS was 16.6 (IQR, 8.4-47.0) and 13.7 (IQR, 8.3-44.1) months, respectively (HR, 0.82; 95% CI, 0.694 to 0.965; P = .02). The median OS (427 events; 68% mature) was 40.5 (IQR, 20.7 to not reached) and 36.2 (IQR, 17.7-53.3) months, respectively (HR, 0.82; 95% CI, 0.680 to 0.996; P = .045). At a 16-month follow-up (cutoff, April 3, 2020; median follow-up, 51.4 months [IQR, 47.0-57.0]), the median OS (511 events; 81% mature) was 41.8 (nab-paclitaxel + gemcitabine) versus 37.7 months (gemcitabine; HR, 0.82; 95% CI, 0.687 to 0.973; P = .0232). At the 5-year follow-up (cutoff, April 9, 2021; median follow-up, 63.2 months [IQR, 60.1-68.7]), the median OS (555 events; 88% mature) was 41.8 versus 37.7 months, respectively (HR, 0.80; 95% CI, 0.678 to 0.947; P = .0091). Eighty-six percent (nab-paclitaxel + gemcitabine) and 68% (gemcitabine) of patients experienced grade ≥ 3 treatment-emergent adverse events. Two patients per study arm died of treatment-emergent adverse events. CONCLUSION: The primary end point (independently assessed DFS) was not met despite favorable OS seen with nab-paclitaxel + gemcitabine.

The Role of Immunotherapy in Pancreatic Cancer.

Pancreatic adenocarcinoma remains one of the most lethal cancers globally, with a significant need for improved therapeutic options. While the recent breakthroughs of immunotherapy through checkpoint inhibitors have dramatically changed treatment paradigms in other malignancies based on considerable survival benefits, this is not so for pancreatic cancer. Chemotherapies with modest benefits are still the cornerstone of advanced pancreatic cancer treatment. Pancreatic cancers are inherently immune-cold tumors and have been largely refractory to immunotherapies in clinical trials. Understanding and overcoming the current failures of immunotherapy through elucidating resistance mechanisms and developing novel therapeutic approaches are essential to harnessing the potential durable benefits of immune-modulating therapy in pancreatic cancer patients.

Cytotoxic Chemotherapy in Advanced Pancreatic Cancer.

Advanced pancreatic cancer remains one of the deadliest malignancies in 2022. Although there has been significant progress in treatment options with improved outcomes in many cancers, this growth has been slow in pancreatic cancer. This article examines specific components of approved first- and second-line therapies for advanced pancreatic cancer treatment and their effectiveness and concludes with a brief exploration of future directions for targeted therapies.

The Next Frontier in Pancreatic Cancer: Targeting the Tumor Immune Milieu and Molecular Pathways.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with abysmal prognosis. It is currently the third most common cause of cancer-related mortality, despite being the 11th most common cancer. Chemotherapy is standard of care in all stages of pancreatic cancer, yet survival, particularly in the advanced stages, often remains under one year. We are turning to immunotherapies and targeted therapies in PDAC in order to directly attack the core features that make PDAC notoriously resistant to chemotherapy. While the initial studies of these agents in PDAC have generally been disappointing, we find optimism in recent preclinical and early clinical research. We find that despite the immunosuppressive effects of the PDAC tumor microenvironment, new strategies, such as combining immune checkpoint inhibitors with vaccine therapy or chemokine receptor antagonists, help elicit strong immune responses. We also expand on principles of DNA homologous recombination repair and highlight opportunities to use agents, such as PARP inhibitors, that exploit deficiencies in DNA repair pathways. Lastly, we describe advances in direct targeting of driver mutations and metabolic pathways and highlight some technological achievements such as novel KRAS inhibitors.

The current state of molecular profiling in gastrointestinal malignancies.

This is a review of the current state of molecular profiling in gastrointestinal (GI) cancers and what to expect from this evolving field in the future. Individualized medicine is moving from broad panel testing of numerous genes or gene products in tumor biopsy samples, identifying biomarkers of prognosis and treatment response, to relatively noninvasive liquid biopsy assays, building on what we have learned in our tumor analysis and growing into its own evolving predictive and prognostic subspecialty. Hence, the field of GI precision oncology is exploding, and this review endeavors to summarize where we are now in preparation for the journey ahead.

A randomized phase II study of SM-88 plus methoxsalen, phenytoin, and sirolimus in patients with metastatic pancreatic cancer treated in the second line and beyond.

BACKGROUND: This trial explores SM-88 used with methoxsalen, phenytoin, and sirolimus (MPS) in pretreated metastatic pancreatic ductal adenocarcinoma (mPDAC) METHODS: Forty-nine patients were randomized to daily 460 or 920 mg oral SM-88 with MPS (SM-88 Regimen). The primary endpoint was objective response rate (RECIST 1.1). RESULTS: Thirty-seven patients completed ≥ one cycle of SM-88 Regimen (response evaluable population). Disease control rate (DCR), overall survival (OS), and progression-free survival (PFS) did not differ significantly between dose levels. Stable disease was achieved in 9/37 patients (DCR, 24.3%); there were no complete or partial responses. Quality-of-life (QOL) was maintained and trended in favor of 920 mg. SM-88 Regimen was well tolerated; a single patient (1/49) had related grade 3 and 4 adverse events, which later resolved. In the intention-to-treat population of 49 patients, the median overall survival (mOS) was 3.4 months (95% CI: 2.7-4.9 months). Those treated in the second line had an mOS of 8.1 months and a median PFS of 3.8 months. Survival was higher for patients with stable versus progressive disease (any line; mOS: 10.6 months vs. 3.9 months; p = 0.01). CONCLUSIONS: SM-88 Regimen has a favorable safety profile with encouraging QOL effects, disease control, and survival trends. This regimen should be explored in the second-line treatment of patients with mPDAC. CLINICALTRIALS: gov Identifier: NCT03512756.

Gastric carcinoma's primary presentation as multiple cutaneous nodules throughout the body.

Cutaneous metastasis resulting from internal primary tumors remains a rare phenomenon. The prompt recognition of these metastases is important, as they are an indicator of advanced disease and poor prognosis. We report the case of a 44-year-old Caucasian man presenting with a four-month history of multiple cutaneous nodules on the face, trunk, and upper extremities. Results from skin biopsy revealed strands and cords of atypical cells concerning for poorly differentiated metastatic carcinoma. An esophagogastroduodenoscopy was performed and a poorly differentiated signet-ring type invasive adenocarcinoma at the lesser curvature of the stomach was found. As the cancer had already metastasized to the skin and bones, the patient was started on chemotherapy with an oxaliplatin-based regimen and denosumab for the bone metastases, with resultant objective response and diagnostic control for greater than one year to the present date.

Randomized Phase II Study of PARP Inhibitor ABT-888 (Veliparib) with Modified FOLFIRI versus FOLFIRI as Second-line Treatment of Metastatic Pancreatic Cancer: SWOG S1513.

PURPOSE: PARP inhibitors synergize with topoisomerase inhibitors, and veliparib plus modified (m) FOLFIRI (no 5-FU bolus) had preliminary activity in metastatic pancreatic cancers. This study evaluated the safety and efficacy of second-line treatment with veliparib and mFOLFIRI versus FOLFIRI (control) for metastatic pancreatic cancer. PATIENTS AND METHODS: This randomized phase II clinical trial led by the SWOG Cancer Research Network enrolled patients between September 1, 2016 and December 13, 2017. The median follow-up was 9 months (IQR 1-27). BRCA1/2 and homologous recombination DNA damage repair (HR-DDR) genetic defects were tested in blood and tumor biopsies. Patients received veliparib 200 mg twice daily, days 1-7 with mFOLFIRI days 3-5, or FOLFIRI in 14-day cycles. RESULTS: After 123 of planned 143 patients were accrued, an interim futility analysis indicated that the veliparib arm was unlikely to be superior to control, and the study was halted. Median overall survival (OS) was 5.4 versus 6.5 months (HR, 1.23; P = 0.28), and median progression-free survival (PFS) was 2.1 versus 2.9 months (HR, 1.39; P = 0.09) with veliparib versus control. Grade 3/4 toxicities were more common with veliparib (69% vs. 58%, P = 0.23). For cancers with HR-DDR defects versus wild-type, median PFS and OS were 7.3 versus 2.5 months (P = 0.05) and 10.1 versus 5.9 months (P = 0.17), respectively, with FOLFIRI, and 2.0 versus 2.1 months (P = 0.62) and 7.4 versus 5.1 months (P = 0.10), respectively, with veliparib plus mFOLFIRI. CONCLUSIONS: Veliparib plus mFOLFIRI did not improve survival for metastatic pancreatic cancer. FOLFIRI should be further studied in pancreatic cancers with HR-DDR defects.

MEK inhibitors in non-V600 BRAF mutations and fusions.

Mutations in BRAF at the 600th codon have proven sensitive to combination BRAF and MEK inhibition. Mutations outside this codon, however, are approximately as common but do not have approved targeted therapy approaches. Herein, we discuss targeting these non-V600 mutation and fusions in BRAF with MEK inhibitors.

Adjuvant Chemotherapy Use in Patients With Locally Advanced Rectal Cancer: A Single-Institution Experience.

BACKGROUND: National Comprehensive Cancer Network guidelines for the treatment of locally advanced rectal cancer advocate neoadjuvant chemoradiotherapy followed by total mesorectal excision and adjuvant chemotherapy (AC). The aim of this retrospective study was to determine our local patterns of AC use and to examine factors that influenced initiation and completion of AC among patients with stage II/III rectal cancer. PATIENTS AND METHODS: The study population consisted of stage II/III rectal cancer patients who were treated at the University of Rochester from 2011 to 2014. Chart reviews were conducted to determine rates of AC initiation and completion. The documented reasons for failure to initiate or complete AC were examined. A multivariate analysis was also completed to evaluate factors that may have influenced the initiation and use of AC. RESULTS: Eighty-one patients were included in the analysis. Median age was 62 years, and 53 (65.4%) were male. Median time from surgery to initiation of AC in those who received AC was 8.0 weeks. Forty-seven patients (58.0%) completed their prescribed AC course. Twenty-four patients (29.6%) did not start AC and 9 patients (11.1%) were unable to complete their course of AC. Primary reasons for not undergoing AC were patient preference (37.5%) and prolonged surgical recovery (33.3%). Primary reasons for not completing AC were treatment toxicities (55.5%) and patient preference (22.2%). Multivariate analysis identified a positive association between clinical stage III disease at diagnosis and initiation of AC. There was no independent association between pathologic response to neoadjuvant therapy at time of surgery and receipt of AC. CONCLUSION: A large proportion of patients at a single academic center did not start or complete their prescribed postoperative AC for locally advanced rectal cancer. Ongoing studies are investigating a total neoadjuvant approach, which may result in better chemotherapy adherence and further improve the pathologic downstaging rate.

Trametinib Activity in Patients with Solid Tumors and Lymphomas Harboring BRAF Non-V600 Mutations or Fusions: Results from NCI-MATCH (EAY131).

PURPOSE: Substantial preclinical evidence and case reports suggest that MEK inhibition is an active approach in tumors with BRAF mutations outside the V600 locus, and in BRAF fusions. Thus, Subprotocol R of the NCI-MATCH study tested the MEK inhibitor trametinib in this population. PATIENTS AND METHODS: The NCI-MATCH study performed genomic profiling on tumor samples from patients with solid tumors and lymphomas progressing on standard therapies or with no standard treatments. Patients with prespecified fusions and non-V600 mutations in BRAF were assigned to Subprotocol R using the NCI-MATCHBOX algorithm. The primary endpoint was objective response rate (ORR). RESULTS: Among 50 patients assigned, 32 were eligible and received therapy with trametinib. Of these, 1 had a BRAF fusion and 31 had BRAF mutations (13 and 19 with class 2 and 3 mutations, respectively). There were no complete responses; 1 patient (3%) had a confirmed partial response (patient with breast ductal adenocarcinoma with BRAF G469E mutation) and 10 patients had stable disease as best response (clinical benefit rate 34%). Median progression-free survival (PFS) was 1.8 months, and median overall survival was 5.7 months. Exploratory subgroup analyses showed that patients with colorectal adenocarcinoma (n = 8) had particularly poor PFS. No new toxicity signals were identified. CONCLUSIONS: Trametinib did not show promising clinical activity in patients with tumors harboring non-V600 BRAF mutations, and the subprotocol did not meet its primary endpoint.

Development of 2 Bromodomain and Extraterminal Inhibitors With Distinct Pharmacokinetic and Pharmacodynamic Profiles for the Treatment of Advanced Malignancies.

PURPOSE: Bromodomain and extraterminal (BET) proteins are key epigenetic transcriptional regulators, inhibition of which may suppress oncogene expression. We report results from 2 independent first-in-human phase 1/2 dose-escalation and expansion, safety and tolerability studies of BET inhibitors INCB054329 (study INCB 54329-101; NCT02431260) and INCB057643 (study INCB 57643-101; NCT02711137). PATIENTS AND METHODS: Patients (≥18 years) with advanced malignancies, ≥1 prior therapy, and adequate organ functions received oral INCB054329 (monotherapy) or INCB057643 (monotherapy or in combination with standard-of-care) in 21-day cycles (or 28-day cycles depending on standard-of-care combination). Primary endpoints were safety and tolerability. RESULTS: Sixty-nine and 134 patients received INCB054329 and INCB057643, respectively. Study INCB 54329-101 has been completed; INCB 57643-101 is currently active, but not recruiting (no patients were receiving treatment as of January 8, 2019). Terminal elimination half-life was shorter for INCB054329 versus INCB057643 (mean [SD], 2.24 [2.03] vs. 11.1 [8.27] hours). INCB054329 demonstrated higher interpatient variability in oral clearance versus INCB057643 (CV%, 142% vs. 45.5%). Most common (>20%) any-grade treatment-related adverse events were similar for both drugs (INCB054329; INCB057643): nausea (35%; 30%), thrombocytopenia (33%; 32%), fatigue (29%; 30%), decreased appetite (26%; 22%). Two confirmed complete responses and 4 confirmed partial responses with INCB057643 were reported as best responses. CONCLUSIONS: INCB057643 exhibited a more favorable PK profile versus INCB054329; exposure-dependent thrombocytopenia was observed with both drugs which limited the target inhibition that could be safely maintained. Further efforts are required to identify patient populations that can benefit most, and an optimal dosing scheme to maximize therapeutic index.