Ampullary Adenocarcinoma, Version 1.2023, NCCN Clinical Practice Guidelines in Oncology.

Ampullary cancers refer to tumors originating from the ampulla of Vater (the ampulla, the intraduodenal portion of the bile duct, and the intraduodenal portion of the pancreatic duct), while periampullary cancers may arise from locations encompassing the head of the pancreas, distal bile duct, duodenum, or ampulla of Vater. Ampullary cancers are rare gastrointestinal malignancies, and prognosis varies greatly based on factors such as patient age, TNM classification, differentiation grade, and treatment modality received. Systemic therapy is used in all stages of ampullary cancer, including neoadjuvant therapy, adjuvant therapy, and first-line or subsequent-line therapy for locally advanced, metastatic, and recurrent disease. Radiation therapy may be used in localized ampullary cancer, sometimes in combination with chemotherapy, but there is no high-level evidence to support its utility. Select tumors may be treated surgically. This article describes NCCN recommendations regarding management of ampullary adenocarcinoma.

Clinical Activity and Safety of Cediranib and Olaparib Combination in Patients with Metastatic Pancreatic Ductal Adenocarcinoma without BRCA Mutation.

LESSONS LEARNED: Cediranib and olaparib combination did not result in clinically meaningful activity in patients with metastatic pancreatic ductal adenocarcinoma without known BRCA mutation. BACKGROUND: Cediranib, a vascular endothelial growth factor receptor inhibitor, suppresses expression of BRCA1/2 and RAD51 inducing homologous recombination DNA repair deficiency (HRD) in several cancer cell lines and xenograft models [1]. Olaparib provides a clinical benefit in patients with metastatic pancreatic adenocarcinoma (mPDAC) with germline BRCA mutation (gBRCAmt) [2]. We hypothesized that cediranib induces HRD in the absence of gBRCAmt and synergizes with olaparib, resulting in an objective response in patients with mPDAC. METHODS: Patients with mPDAC with at least one prior systemic chemotherapy were enrolled. Patients with known gBRCAmt were excluded. Patients took cediranib 30 mg daily and olaparib 200 mg twice daily, orally. The primary endpoint was objective response (OR) rate. RESULTS: Nineteen patients received the study drugs. Seven patients came off treatment before the first restaging scan: six because of clinical progression and one because of an adverse event. No OR was observed. Six patients had stable disease (SD) as a best overall response. The median duration of SD was 3.1 months. The median overall survival was 3.4 months. Common treatment-related adverse events were fatigue, hypertension, and diarrhea. CONCLUSION: Cediranib and olaparib combination did not result in clinically meaningful activity in patients with mPDAC without gBRCAmt.

Pancreatic Adenocarcinoma, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology.

Pancreatic cancer is the fourth leading cause of cancer-related death among men and women in the United States. A major challenge in treatment remains patients' advanced disease at diagnosis. The NCCN Guidelines for Pancreatic Adenocarcinoma provides recommendations for the diagnosis, evaluation, treatment, and follow-up for patients with pancreatic cancer. Although survival rates remain relatively unchanged, newer modalities of treatment, including targeted therapies, provide hope for improving patient outcomes. Sections of the manuscript have been updated to be concordant with the most recent update to the guidelines. This manuscript focuses on the available systemic therapy approaches, specifically the treatment options for locally advanced and metastatic disease.

Immune-Related Adverse Events and Immune Checkpoint Inhibitor Efficacy in Patients with Gastrointestinal Cancer with Food and Drug Administration-Approved Indications for Immunotherapy.

INTRODUCTION: Immune-related adverse event (IRAE) onset may represent a clinical biomarker for anti-programmed cell death protein 1 (PD-1) antibody response based on emerging evidence from patients with various advanced malignancies. This phenomenon has not been previously reported in a multidisease cohort of patients with gastrointestinal (GI) cancer with Food and Drug Administration (FDA)-approved indications to receive immune checkpoint inhibitor therapy. MATERIALS AND METHODS: The study was a multicenter retrospective cohort analysis of 76 patients with GI cancer who had received anti-PD-1 antibodies for FDA-approved indications. The primary and secondary outcomes of the study were progression-free survival (PFS) and overall survival (OS) in patients based upon IRAE presence, respectively. PFS and OS were estimated by the Kaplan-Meier method; a Cox proportional-hazards model adjusted for IRAE onset, patient age, and enrolling institution was used to analyze outcomes. RESULTS: Median PFS and OS were prolonged in patients who experienced IRAEs compared with those who did not experience them (PFS: not reached [NR] vs. 3.9 months [hazard ratio (HR) 0.13, 95% confidence interval (CI) 0.05-0.3, p < .001]; OS: NR vs. 7.4 months [HR 0.11, 95% CI 0.03-0.36, p < .001]). Among patients who experienced IRAEs, there were no significant differences in PFS and OS by either initial IRAE severity, management, or time to onset. CONCLUSION: Patients with gastrointestinal cancer who experienced IRAEs while on anti-PD-1 antibodies demonstrated significant improvements in PFS and OS compared with their counterparts who did not develop IRAEs. Although these findings add to results from studies in other tumor types, larger prospective studies are needed prior to clinical adoption of IRAE onset as a biomarker for immune checkpoint inhibitor response. IMPLICATIONS FOR PRACTICE: Predictive clinical biomarkers for immune checkpoint inhibitor response have been understudied in the field of immuno-oncology. Immune-related adverse event onset appears to be one such biomarker. Across tumor types, immune-related adverse event onset has been associated with response to anti-programmed cell death protein 1 (PD-1) antibodies. The results of this study demonstrate this for the first time in patients with gastrointestinal cancer receiving anti-PD-1 antibodies. Before immune-related adverse event onset can be adopted clinically as a predictive biomarker for immune checkpoint inhibitor response, however, larger prospective studies are needed to better understand the nuances between immune-related adverse event characteristics (severity, site, management, timing of onset) and immune checkpoint inhibitor effectiveness.

A phase 1b dose escalation study of Wnt pathway inhibitor vantictumab in combination with nab-paclitaxel and gemcitabine in patients with previously untreated metastatic pancreatic cancer.

Vantictumab is a fully human monoclonal antibody that inhibits Wnt pathway signaling through binding FZD1, 2, 5, 7, and 8 receptors. This phase Ib study evaluated vantictumab in combination with nab-paclitaxel and gemcitabine in patients with untreated metastatic pancreatic adenocarcinoma. Patients received vantictumab at escalating doses in combination with standard dosing of nab-paclitaxel and gemcitabine according to a 3 + 3 design. A total of 31 patients were treated in 5 dosing cohorts. Fragility fractures attributed to vantictumab occurred in 2 patients in Cohort 2 (7 mg/kg every 2 weeks), and this maximum administered dose (MAD) on study was considered unsafe. The dosing schedule was revised to every 4 weeks for Cohorts 3 through 5, with additional bone safety parameters added. Sequential dosing of vantictumab followed by nab-paclitaxel and gemcitabine was also explored. No fragility fractures attributed to vantictumab occurred in these cohorts; pathologic fracture not attributed to vantictumab was documented in 2 patients. The study was ultimately terminated due to concerns around bone-related safety, and thus the maximum tolerated dose (MTD) of the combination was not determined. The MAD of vantictumab according to the revised dosing schedule was 5 mg/kg (n = 16).

Pancreatic Adenocarcinoma, Version 1.2019.

The NCCN Guidelines for Pancreatic Adenocarcinoma discuss the diagnosis and management of adenocarcinomas of the exocrine pancreas and are intended to assist with clinical decision-making. These NCCN Guidelines Insights discuss important updates to the 2019 version of the guidelines, focusing on postoperative adjuvant treatment of patients with pancreatic cancers.

Dual Src and EGFR inhibition in combination with gemcitabine in advanced pancreatic cancer: phase I results : A phase I clinical trial.

Pancreatic adenocarcinoma remains a major therapeutic challenge, as the poor (<8%) 5-year survival rate has not improved over the last three decades. Our previous preclinical data showed cooperative attenuation of pancreatic tumor growth when dasatinib (Src inhibitor) was added to erlotinib (EGFR inhibitor) and gemcitabine. Thus, this study was designed to determine the maximum-tolerated dose of the triplet combination. Standard 3 + 3 dose escalation was used, starting with daily oral doses of 70 mg dasatinib and 100 mg erlotinib with gemcitabine on days 1, 8, and 15 (800 mg/m2) of a 28-day cycle (L0). Nineteen patients were enrolled, yet 18 evaluable for dose-limiting toxicities (DLTs). One DLT observed at L0, however dasatinib was reduced to 50 mg (L-1) given side effects observed in the first two patients. At L-1, a DLT occurred in 1/6 patients and dose was re-escalated to L0, where zero DLTs reported in next four patients. Dasatinib was escalated to 100 mg (L1) where 1/6 patients experienced a DLT. Although L1 was tolerable, dose escalation was stopped as investigators felt L1 was within the optimal therapeutic window. Most frequent toxicities were anemia (89%), elevated aspartate aminotransferase (79%), fatigue (79%), nausea (79%), elevated alanine aminotransferase (74%), lymphopenia (74%), leukopenia (74%), neutropenia (63%), and thrombocytopenia (63%), most Grade 1/2. Stable disease as best response was observed in 69% (9/13). Median progression-free and overall survival was 3.6 and 8 months, respectively. Dasatinib, erlotinib, and gemcitabine was safe with manageable side effects, and with encouraging preliminary clinical activity in advanced pancreatic cancer.

Phase II study of the Multikinase inhibitor of angiogenesis, Linifanib, in patients with metastatic and refractory colorectal cancer expressing mutated KRAS.

Background Targeting angiogenesis in advanced colorectal cancer (CRC) has been one of the many factors prolonging survival. Bevacizumab was the first agent to demonstrate this, but even after progression on bevacizumab, continued VEGF-inhibition continues to improve survival. Combining epidermal growth factor receptor monoclonal antibodies with standard frontline therapies have also improved clinical outcomes, yet the improved benefit is not observed in patients with mutant KRAS. Thus, an unmet medical need exists to develop additional therapeutic options for patients with KRAS mutant CRC. Methods Patients received the anti-angiogenic agent linifanib at the recommended phase II dose of 17.5 mg. Primary endpoint was objective response rate (ORR), with a goal of 10%. Secondary endpoints were progression-free survival (PFS), overall survival (OS), and safety. Simon's optimal two-stage design was used to assess futility. Linifanib was considered inactive if two or fewer patients among the first 30 achieved an objective response. Results Thirty patients were enrolled on study. Grade 3 treatment-related toxicities occurring in at least two patients were fatigue, hypertension, proteinuria, diarrhea, nausea, oral pain, vomiting, thrombocytopenia, and arthralgia. Although no responses were observed, 63.5% of patients achieved stable disease. The median PFS and OS were 4.7 months and 9.5 months, respectively. Stopping rules for lack of clinical efficacy led to study closure. Conclusion Despite observing zero responses, a majority of patients had stable disease and eight patients had stable disease lasting longer than 5 months. These results suggest that linifanib has some anti-tumor activity in KRAS mutant metastatic and refractory CRC.

A phase I trial investigating pulsatile erlotinib in combination with gemcitabine and oxaliplatin in advanced biliary tract cancers.

Advanced biliary tract cancers (ABTC) are among the deadliest malignancies with limited treatment options after progression on standard-of-care chemotherapy, which includes gemcitabine (GEM) and oxaliplatin (OX). The epidermal growth factor receptor inhibitor erlotinib has been explored in ABTC with modest efficacy. Erlotinib given continuously may antagonize the action of chemotherapy against cycling tumor cells, but pulsatile dosing of erlotinib with chemotherapy may improve efficacy. The purpose of this study was to assess the safety of pulsatile erlotinib with GEMOX. This was a single-institution phase Ib study that enrolled adult patients with unresectable or metastatic biliary tract, pancreas, duodenal, or ampullary carcinomas that have not received any prior treatment for their disease. Dose escalation followed a standard 3 + 3 design, and dose-limiting toxicities (DLTs) were any treatment-related, first course non-hematologic grade ≥ 3 toxicity, except nausea/vomiting, or grade 4 hematologic toxicity. A dose expansion cohort in ABTC was treated at the MTD. Twenty-eight patients were enrolled and 4 dose levels were explored. The MTD was erlotinib 150 mg + GEM 800 mg/m2 + OX 85 mg/m2. DLTs were diarrhea and anemia. Most frequent toxicities were nausea (78 %), fatigue (71 %), neuropathy (68 %), and diarrhea (61 %), predominantly grade 1-2. In the ABTC patients, the objective response and disease control rates were 29 % and 94 %, respectively, and median overall survival was 18 months. Erlotinib plus GEMOX was well tolerated. Encouraging anti-tumor activity was seen as evidenced by a high disease control rate and longer median OS than standard chemotherapy in the patients with ABTC.

Pancreatic Adenocarcinoma, Version 2.2017, NCCN Clinical Practice Guidelines in Oncology.

Ductal adenocarcinoma and its variants account for most pancreatic malignancies. High-quality multiphase imaging can help to preoperatively distinguish between patients eligible for resection with curative intent and those with unresectable disease. Systemic therapy is used in the neoadjuvant or adjuvant pancreatic cancer setting, as well as in the management of locally advanced unresectable and metastatic disease. Clinical trials are critical for making progress in treatment of pancreatic cancer. The NCCN Guidelines for Pancreatic Adenocarcinoma focus on diagnosis and treatment with systemic therapy, radiation therapy, and surgical resection.

Safety and Efficacy of Avelumab in Small Bowel Adenocarcinoma.

INTRODUCTION: Small bowel adenocarcinomas (SBAs) are rare and frequently treated like large intestinal adenocarcinomas. However, SBAs have a very different microenvironment and could respond differently to the same therapies. Our previous data suggested that SBAs might benefit from targeting the PD-1/PD-L1 axis based on PD-L1 staining in almost 50% of SBA tissue samples tested. Thus, we designed a phase 2 study to explore safety and efficacy of avelumab in SBA. PATIENTS AND METHODS: Patients with advanced or metastatic disease were enrolled; ampullary tumors were considered part of the duodenum and allowed. Prior PD-1/PD-L1 inhibition was not allowed. Avelumab (10 mg/kg) was given every 2 weeks, and imaging was performed every 8 weeks. Primary endpoint was response rate. RESULTS: Eight patients (n = 5, small intestine; n = 3, ampullary) were enrolled, with a majority (88%) being male and a median age of 61 years. Of 7 efficacy-evaluable patients, 2 (29%) experienced partial responses; stable disease occurred in 3 additional patients (71%). Median progression-free survival was 3.35 months. Most frequent, related toxicities were anemia, fatigue, and infusion-related reaction (25% each), mostly grade ≤2; grade 3 hypokalemia and hyponatremia occurred in one patient, and another reported grade 4 diabetic ketoacidosis. CONCLUSIONS: Despite the observed benefit, accrual was slower than expected and the study was closed early due to feasibility. A general clinic observation was that patients were receiving immunotherapy off-label as the availability of these agents increased. Off-label availability and disease rarity were likely drivers of insufficient accrual.

External Validation of a Clinical Score for Patients With Neuroendocrine Tumors Under Consideration for Peptide Receptor Radionuclide Therapy.

Importance: Despite the benefit of peptide receptor radionuclide therapy (PRRT) for patients with well-differentiated neuroendocrine tumors (WD NETs), no clinical metric to anticipate benefit from the therapy for individual patients has been previously defined. Objective: To assess whether the prognostic ability of the clinical score (CS) could be validated in an external cohort of patients with WD NETs. Design, Setting, and Participants: This multicenter cohort study's analysis included patients with WD NETs who were under consideration for peptide receptor radionuclide therapy (PRRT) with lutetium-177 (177Lu)-dotatate between March 1, 2016, and March 17, 2020. The original cohort included patients from Vanderbilt-Ingram Cancer Center. The validation cohort included patients from Ochsner Medical Center, Markey Cancer Center, and Rush Medical Center. Patients with paragangliomas, pheochromocytomas and neuroblastomas were excluded. Statistical analysis was performed from June to November 2021. Exposures: PRRT with 177Lu-dotatate or alternate therapies such as everolimus, sunitinib, or capecitabine plus temozolomide. Main Outcomes and Measures: The primary outcome was progression-free survival (PFS) and was estimated by the Kaplan-Meier method; a Cox proportional-hazards model adjusting for primary tumor site, tumor grade, and number of PRRT doses administered was used to analyze association between CS and outcomes. Results: A total of 126 patients (median age [IQR] age: 63.6 [52.9-70.7] years; 64 male individuals) were included in the validation cohort, and the combined cohort (validation and original cohorts combined) had a total of 248 patients (median [IQR] patient age: 63.3 [53.3-70.3] years; 126 male individuals). In the validation cohort, on multivariable analysis, for each 2-point increase in CS, PFS decreased significantly (hazard ratio, 2.61; 95% CI, 1.64-4.16). After finding an association of the CS with PFS in the validation cohort, the original and validation cohorts were combined into the cohort for this analysis. On multivariable analysis, for each 2-point increase in CS, PFS decreased significantly (hazard ratio, 2.52; 95% CI, 1.89-3.36). Conclusions and Relevance: Increases in CS were associated with worsening PFS in the validation cohort, validating findings from the original cohort. These findings suggest that the CS, to our knowledge, represents the first clinical metric to estimate anticipated benefit from PRRT for patients with WD NETs and may be a clinical tool for patients being considered for PRRT.

First-Line Nivolumab Plus Low-Dose Ipilimumab for Microsatellite Instability-High/Mismatch Repair-Deficient Metastatic Colorectal Cancer: The Phase II CheckMate 142 Study.

PURPOSE: Nivolumab received US Food and Drug Administration approval as a single agent or in combination with ipilimumab in patients with microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) metastatic colorectal cancer (mCRC) that progressed following treatment with a fluoropyrimidine, oxaliplatin, and irinotecan based on CheckMate 142. Presented are results of nivolumab plus low-dose ipilimumab in the first-line therapy cohort from the phase II CheckMate 142 study. PATIENTS AND METHODS: Patients with no prior treatment in the metastatic setting for MSI-H/dMMR CRC were treated with nivolumab every 2 weeks plus low-dose ipilimumab every 6 weeks until disease progression. The primary end point was objective response rate (investigator assessment; RECIST v1.1). RESULTS: Median age of treated patients was 66 years (N = 45). Median follow-up was 29.0 months. Objective response rate and disease control rate were 69% (95% CI, 53 to 82) and 84% (95% CI, 70.5 to 93.5), respectively, with 13% complete response rate. Median duration of response was not reached; 74% of responders had ongoing responses at data cutoff. Median progression-free survival and median overall survival were not reached with minimum follow-up of 24.2 months (24-month rates, 74% and 79%, respectively). Clinical benefit was observed regardless of baseline demographic and tumor characteristics, including BRAF or KRAS mutation status. In a post hoc analysis, of 14 patients who discontinued treatment and did not receive subsequent therapy, 10 remained progression-free. Patient-reported outcomes were stable over the treatment period. Grade 3-4 treatment-related adverse events occurred in 22% of patients; 13% discontinued because of any-grade treatment-related adverse events. CONCLUSION: Nivolumab plus low-dose ipilimumab demonstrated robust and durable clinical benefit and was well tolerated as a first-line treatment for MSI-H/dMMR mCRC. Based on these promising data, randomized studies are warranted.

First-in-human phase I/II, open-label study of the anti-OX40 agonist INCAGN01949 in patients with advanced solid tumors.

BACKGROUND: OX40 is a costimulatory receptor upregulated on antigen-activated T cells and constitutively expressed on regulatory T cells (Tregs). INCAGN01949, a fully human immunoglobulin G1κ anti-OX40 agonist monoclonal antibody, was designed to promote tumor-specific immunity by effector T-cell activation and Fcγ receptor-mediated Treg depletion. This first-in-human study was conducted to determine the safety, tolerability, and preliminary efficacy of INCAGN01949. METHODS: Phase I/II, open-label, non-randomized, dose-escalation and dose-expansion study conducted in patients with advanced or metastatic solid tumors. Patients received INCAGN01949 monotherapy (7-1400 mg) in 14-day cycles while deriving benefit. Safety measures, clinical activity, pharmacokinetics, and pharmacodynamic effects were assessed and summarized with descriptive statistics. RESULTS: Eighty-seven patients were enrolled; most common tumor types were colorectal (17.2%), ovarian (8.0%), and non-small cell lung (6.9%) cancers. Patients received a median three (range 1-9) prior therapies, including immunotherapy in 24 patients (27.6%). Maximum tolerated dose was not reached; one patient (1.1%) receiving 350 mg dose reported dose-limiting toxicity of grade 3 colitis. Treatment-related adverse events were reported in 45 patients (51.7%), with fatigue (16 (18.4%)), rash (6 (6.9%)), and diarrhea (6 (6.9%)) being most frequent. One patient (1.1%) with metastatic gallbladder cancer achieved a partial response (duration of 6.3 months), and 23 patients (26.4%) achieved stable disease (lasting >6 months in one patient). OX40 receptor occupancy was maintained over 90% among all patients receiving doses of ≥200 mg, while no treatment-emergent antidrug antibodies were detected across all dose levels. Pharmacodynamic results demonstrated that treatment with INCAGN01949 did not enhance proliferation or activation of T cells in peripheral blood or reduce circulating Tregs, and analyses of tumor biopsies did not demonstrate any consistent increase in effector T-cell infiltration or function, or decrease in infiltrating Tregs. CONCLUSION: No safety concerns were observed with INCAGN01949 monotherapy in patients with metastatic or advanced solid tumors. However, tumor responses and pharmacodynamic effects on T cells in peripheral blood and post-therapy tumor biopsies were limited. Studies evaluating INCAGN01949 in combination with other therapies are needed to further evaluate the potential of OX40 agonism as a therapeutic approach in patients with advanced solid tumors. TRIAL REGISTRATION NUMBER: NCT02923349.

Treatment of early-stage pancreatic cancer.

Pancreatic cancer is the fourth leading cause of cancer death, and it is estimated that over 43,000 people would be diagnosed with and over 36,000 people would die of pancreatic cancer in the United States in 2010. Surgical resection remains the only chance for possible cure, but only 15% to 20% of patients newly diagnosed with pancreatic cancer are considered for surgical resection. Of these, the median five-year survival rate is still less than 20%, with most resections resulting in recurrent disease. This suggests that even seemingly resectable pancreatic cancer has microscopic systemic spread before operative intervention occurs. Both adjuvant and neoadjuvant therapies have been studied in an effort to improve survival for patients with resectable pancreatic cancer.

Recent advances in the treatment of pancreatic cancer.

Pancreatic ductal adenocarcinoma is one of the deadliest solid tumor malignancies and is projected to become a leading cause of cancer-related death in coming years. Improving quality of life and survival amongst these patients will require new ideas and novel therapies in a multidisciplinary approach. This review will cover the most recent advances in the comprehensive treatment of pancreatic cancer and place them within a historical context when necessary. Treatment of all disease stages will be discussed, but the focus is on systemic therapy as novel drugs and new treatment combinations enter the clinic. This will include more aggressive chemotherapy in earlier disease stages, approved uses for immunotherapy, and targetable mutations. In addition, negative trials of importance and controversial topics will be noted.

Phase I Study of Trifluridine/Tipiracil Plus Irinotecan and Bevacizumab in Advanced Gastrointestinal Tumors.

PURPOSE: This two-part phase Ib trial determined the maximum tolerated dose (MTD) of the combination of trifluridine/tipiracil (FTD/TPI) and irinotecan in patients with advanced gastrointestinal tumors, and evaluated the safety, pharmacokinetics, and antitumor activity of the FTD/TPI, irinotecan, and bevacizumab triplet combination in previously treated metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: Dose escalation (3+3 design) in advanced gastrointestinal tumors was followed by expansion in mCRC. During dose escalation, patients received FTD/TPI (20-35 mg/m2 twice daily; days 1-5 of a 14-day cycle) and irinotecan (120-180 mg/m2; day 1). During expansion, the MTD of FTD/TPI and irinotecan plus bevacizumab (5 mg/kg; day 1) was administered. RESULTS: Fifty patients (26 across six dose-escalation cohorts and 24 in the expansion phase) were enrolled. Two dose-limiting toxicities (fatigue and neutropenia) were observed in the dose-escalation phase, and MTD was defined as FTD/TPI 25 mg/m2 twice daily plus irinotecan 180 mg/m2. In the expansion phase, 83% (20/24) experienced any-cause grade ≥3 adverse events (AEs) with the triplet combination, most frequently neutropenia (42%), leukopenia (25%), and diarrhea (12%). AEs of any-cause led to dosing interruptions, modifications, and discontinuations in 29%, 17%, and 4% of patients, respectively. No treatment-related deaths occurred. Three patients (12%) experienced partial responses and 16 (67%) patients had stable disease lasting >4 months. The median progression-free survival was 7.9 months (95% confidence interval, 5.1-13.4 months). CONCLUSIONS: Tolerability and activity observed in this phase I trial support further investigation of the FTD/TPI-irinotecan-bevacizumab combination in previously treated mCRC.

Phase Ib Study of Wnt Inhibitor Ipafricept with Gemcitabine and nab-paclitaxel in Patients with Previously Untreated Stage IV Pancreatic Cancer.

PURPOSE: The recombinant fusion protein ipafricept blocks Wnt signaling, and in combination with gemcitabine and nab-paclitaxel caused tumor regression in xenografts. This phase Ib study evaluated the combination of ipafricept with nab-paclitaxel + gemcitabine in patients with untreated metastatic pancreatic adenocarcinoma (mPDAC). PATIENTS AND METHODS: Dose escalation started with standard dose nab-paclitaxel + gemcitabine and ipafricept (3.5 mg/kg days 1, 15). Because of fragility fractures seen with different anti-Wnt agents, following cohorts had ≥6 patients treated with ipafricept 3 to 5 mg/kg on day 1, and included bone marker monitoring and prophylactic bisphosphonates as indicated. On the basis of preclinical data, sequential dosing was evaluated in cohort 4 (ipafricept day 1 followed nab-paclitaxel + gemcitabine day 3). Objectives included safety, MTD, recommended phase II dose, pharmacokinetics, immunogenicity, pharmacodynamics, and efficacy. RESULTS: A total of 26 patients were enrolled, five in cohort 1 and seven each in cohorts 2-4. ipafricept-related adverse events (AEs) of any grade included fatigue, nausea, vomiting, anorexia, and pyrexia. ipafricept-related AEs grade ≥3 included two events of aspartate aminotransferase elevation, and one each of nausea, rash, vomiting, and leucopenia. No dose-limiting toxicities or fragility fractures were observed. Nine patients (34.6%) had partial response, 12 (46.2%) stable disease as best response, with clinical benefit rate of 81%. Median progression-free survival was 5.9 m [95% confidence interval (CI), 3.4-18.4], median overall survival was 9.7 m (95% CI, 7.0-14). The study was terminated by the sponsor due to bone-related toxicity within this therapeutic program and concerns for commercial viability. One patient remains on therapy under compassionate use. CONCLUSIONS: Ipafricept can be administered with nab-paclitaxel + gemcitabine with reasonable tolerance. Wnt pathway remains a therapeutic target of interest in mPDAC.

Phase I Trial of Trametinib with Neoadjuvant Chemoradiation in Patients with Locally Advanced Rectal Cancer.

PURPOSE: The RAS/RAF/MEK/ERK signaling pathway is critical to the development of colorectal cancers, and KRAS, NRAS, and BRAF mutations foster resistance to radiation. We performed a phase I trial to determine the safety of trametinib, a potent MEK1/2 inhibitor, with 5-fluorouracil (5-FU) chemoradiation therapy (CRT) in patients with locally advanced rectal cancer (LARC). PATIENTS AND METHODS: Patients with stage II/III rectal cancer were enrolled on a phase I study with 3+3 study design, with an expansion cohort of 9 patients at the MTD. Following a 5-day trametinib lead-in, with pre- and posttreatment tumor biopsies, patients received trametinib and CRT, surgery, and adjuvant chemotherapy. Trametinib was given orally daily at 3 dose levels: 0.5 mg, 1 mg, and 2 mg. CRT consisted of infusional 5-FU 225 mg/m2/day and radiation dose of 28 daily fractions of 1.8 Gy (total 50.4 Gy). The primary endpoint was to identify the MTD and recommended phase II dose. IHC staining for phosphorylated ERK (pERK) and genomic profiling was performed on the tumor samples. RESULTS: Patients were enrolled to all dose levels, and 18 patients were evaluable for toxicities and responses. Treatment was well tolerated, and there was one dose-limiting toxicity of diarrhea, which was attributed to CRT rather than trametinib. At the 2 mg dose level, 25% had pathologic complete response. IHC staining confirmed dose-dependent decrease in pERK with increasing trametinib doses. CONCLUSIONS: The combination of trametinib with 5-FU CRT is safe and well tolerated, and may warrant additional study in a phase II trial, perhaps in a RAS/RAF-mutant selected population.

Advanced pancreatic cancer clinical trials: The continued underrepresentation of older patients.

OBJECTIVES: Older patients make up the majority of patients with pancreatic cancer, with a median age of 71 years at diagnosis. However, older patients are underrepresented in clinical trials in pancreatic cancer. This study investigates trends in age distribution of patients enrolled in clinical trials for advanced pancreatic cancer over time, and examines outcomes and toxicity in older patient subgroups from two studies conducted by Eastern Cooperative Oncology Group and American College of Radiology Imaging Network (ECOG-ACRIN) in this disease. MATERIALS AND METHODS: 16,042 patients from 38 phase III clinical trials for locally advanced or metastatic pancreatic adenocarcinoma published between 1997 and 2016 were identified and included in this analysis. Outcomes and toxicity by age were examined in two of the trials, ECOG-ACRIN trials E2297 and E6201, which included a total of 1146 patients. RESULTS: The median age across the trials was 62.7 years; median ages for individual trials ranged from 57 years to 66 years. Weighted linear regression showed no significant change in median age over time. Combined analysis of the two ECOG-ACRIN trials demonstrated higher rates of fatigue, thrombocytopenia, and infection in those ≥75 years compared with those <75 years, but despite this showed no difference in overall survival (OS) or progression-free survival (PFS) (OS: 5.7 vs. 5.6 months and PFS: 2.8 vs 3.5 months). CONCLUSIONS: Enrollment of older adults in phase III pancreatic cancer clinical trials has not increased over time, despite increasing number of older patients seen in clinic. Increased efforts are needed to enhance enrollment of older patients in clinical trials, and to promote trials specifically for older patients, in order to improve the evidence base for treating this patient population.