Polo-like Kinase 1 Inhibition in KRAS-Mutated Metastatic Colorectal Cancer

Inhibition of Polo-like kinase 1 (Plk1) is a promising new target and therapeutic strategy in metastatic colorectal cancer, especially those with KRAS mutations. New data support further development of onvansertib, and highlights the role of circulating tumor DNA in phase I clinical trials. See related article by Ahn et al., p. 2039.

Efficacy and Safety of Radiation Segmentectomy with 90Y Resin Microspheres for Hepatocellular Carcinoma

Background Limited data are available on radiation segmentectomy (RS) for treatment of hepatocellular carcinoma (HCC) using yttrium 90 (90Y) resin microsphere doses determined by using a single-compartment medical internal radiation dosimetry (MIRD) model. Purpose To evaluate the efficacy and safety of RS treatment of HCC with 90Y resin microspheres using a single-compartment MIRD model and correlate posttreatment dose with outcomes. Materials and Methods This retrospective single-center study included adult patients with HCC who underwent RS with 90Y resin microspheres between July 2014 and December 2022. Posttreatment PET/CT and dosimetry were performed. Adverse events were assessed using the Common Terminology Criteria for Adverse Events, version 5.0. Per-lesion and overall response rates (ie, complete response [CR], objective response, disease control, and duration of response) were assessed at imaging using the Modified Response Evaluation Criteria in Solid Tumors, and overall survival (OS) was assessed using Kaplan-Meier analysis. Results Among 67 patients (median age, 69 years [IQR, 63-78 years]; 54 male patients) with HCC, median tumor absorbed dose was 232 Gy (IQR, 163-405 Gy). At 3 months, per-lesion and overall (per-patient) CR was achieved in 47 (70%) and 41 (61%) of 67 patients, respectively. At 6 months (n = 46), per-lesion rates of objective response and disease control were both 94%, and per-patient rates were both 78%. A total of 88% (95% CI: 79 99) and 72% (95% CI: 58, 90) of patients had a per-lesion and overall duration of response of 1 year or greater. At 1 month, a grade 3 clinical adverse event (abdominal pain) occurred in one of 67 (1.5%) patients. Median posttreatment OS was 26 months (95% CI: 20, not reached). Disease progression at 2 years was lower in the group that received 300 Gy or more than in the group that received less than 300 Gy (17% vs 61%; P = .047), with no local progression in the former group through the end of follow-up. Conclusion Among patients with HCC who underwent RS with 90Y resin microspheres, 88% and 72% achieved a per-lesion and overall duration of response of 1 year or greater, respectively, with one grade 3 adverse event. In patients whose tumors received 300 Gy or more according to posttreatment dosimetry, a disease progression benefit was noted. © RSNA, 2024 Supplemental material is available for this article.

Protein biomarkers and alternatively methylated cell-free DNA detect early stage pancreatic cancer

OBJECTIVE

Pancreatic ductal adenocarcinoma (PDAC) is commonly diagnosed at an advanced stage. Liquid biopsy approaches may facilitate detection of early stage PDAC when curative treatments can be employed.

DESIGN

To assess circulating marker discrimination in training, testing and validation patient cohorts (total n=426 patients), plasma markers were measured among PDAC cases and patients with chronic pancreatitis, colorectal cancer (CRC), and healthy controls. Using CA19-9 as an anchor marker, measurements were made of two protein markers (TIMP1, LRG1) and cell-free DNA (cfDNA) pancreas-specific methylation at 9 loci encompassing 61 CpG sites.

RESULTS

Comparative methylome analysis identified nine loci that were differentially methylated in exocrine pancreas DNA. In the training set (n=124 patients), cfDNA methylation markers distinguished PDAC from healthy and CRC controls. In the testing set of 86 early stage PDAC and 86 matched healthy controls, CA19-9 had an area under the receiver operating characteristic curve (AUC) of 0.88 (95% CI 0.83 to 0.94), which was increased by adding TIMP1 (AUC 0.92; 95% CI 0.88 to 0.96; p=0.06), LRG1 (AUC 0.92; 95% CI 0.88 to 0.96; p=0.02) or exocrine pancreas-specific cfDNA methylation markers at nine loci (AUC 0.92; 95% CI 0.88 to 0.96; p=0.02). In the validation set of 40 early stage PDAC and 40 matched healthy controls, a combined panel including CA19-9, TIMP1 and a 9-loci cfDNA methylation panel had greater discrimination (AUC 0.86, 95% CI 0.77 to 0.95) than CA19-9 alone (AUC 0.82; 95% CI 0.72 to 0.92).

CONCLUSION

A combined panel of circulating markers including proteins and methylated cfDNA increased discrimination compared with CA19-9 alone for early stage PDAC.

A Large-Scale Proteomics Resource of Circulating Extracellular Vesicles for Biomarker Discovery in Pancreatic Cancer

Pancreatic cancer has the worst prognosis of all common tumors. Earlier cancer diagnosis could increase survival rates and better assessment of metastatic disease could improve patient care. As such, there is an urgent need to develop biomarkers to diagnose this deadly malignancy earlier. Analyzing circulating extracellular vesicles (cEVs) using 'liquid biopsies' offers an attractive approach to diagnose and monitor disease status. However, it is important to differentiate EV-associated proteins enriched in patients with pancreatic ductal adenocarcinoma (PDAC) from those with benign pancreatic diseases such as chronic pancreatitis and intraductal papillary mucinous neoplasm (IPMN). To meet this need, we combined the novel EVtrap method for highly efficient isolation of EVs from plasma and conducted proteomics analysis of samples from 124 individuals, including patients with PDAC, benign pancreatic diseases and controls. On average, 912 EV proteins were identified per 100μL of plasma. EVs containing high levels of PDCD6IP, SERPINA12 and RUVBL2 were associated with PDAC compared to the benign diseases in both discovery and validation cohorts. EVs with PSMB4, RUVBL2 and ANKAR were associated with metastasis, and those with CRP, RALB and CD55 correlated with poor clinical prognosis. Finally, we validated a 7-EV protein PDAC signature against a background of benign pancreatic diseases that yielded an 89% prediction accuracy for the diagnosis of PDAC. To our knowledge, our study represents the largest proteomics profiling of circulating EVs ever conducted in pancreatic cancer and provides a valuable open-source atlas to the scientific community with a comprehensive catalogue of novel cEVs that may assist in the development of biomarkers and improve the outcomes of patients with PDAC.

Results from a phase 1a/1b study of botensilimab (BOT), a novel innate/adaptive immune activator, plus balstilimab (BAL; anti-PD-1 antibody) in metastatic heavily pretreated microsatellite stable colorectal cancer (MSS CRC)

LBA8

Background: BOT promotes optimized T cell priming, activation and memory formation by strengthening antigen presenting cell/T cell co-engagement. As an Fc-enhanced next-generation anti–CTLA-4 antibody, BOT also promotes intratumoral regulatory T cell depletion and reduces complement fixation. We present results from patients with MSS CRC treated with BOT + BAL in an expanded phase 1a/1b study; NCT03860272. Methods: Patients (pts) with metastatic MSS CRC received BOT 1 or 2 mg/kg every 6 weeks (Q6W) + BAL 3 mg/kg every 2 weeks. Crossover from monotherapy to combination therapy was permitted (rescue) as well as fixed-dosing (150 mg BOT Q6W + 450 mg BAL every 3 weeks). Results: Fifty-nine combination pts were evaluable for efficacy/safety (treated as of 19 May 2022 with ≥1 Q6W imaging assessment), including one rescue and one fixed-dose pt. Median pt age was 57 (range, 25-83), 58% were female, and 76% received at least three prior lines of therapy including prior immunotherapy (34%). Median follow-up was 6.4 months (range, 1.6-29.5). In all pts, objective response rate (ORR) was 22% (95% CI, 12-35), disease control rate (DCR) was 73% (95% CI, 60-84), and median duration of response (DOR) was not reached (NR), with 9/13 responses ongoing. The 12-month overall survival (OS) rate was 61% (95% CI, 42-75), with median OS NR. Of the 13 responders, 9 had RAS mutations (7 KRAS, 2 NRAS), 0 had BRAF mutations, 0/10 had a TMB of ≥10 mutations/Mb, and 1/7 was PD-L1 positive (≥1% combined positive score). A subgroup analysis was conducted by the dose of BOT received . In 1 mg/kg pts (n=8), ORR was 38% (3/8; 95% CI, 9-76) and DCR was 100% (8/8; 95% CI, 63-100); in 2 mg/kg pts (n=50), ORR was 20% (10/50; 95% CI, 10-34) and DCR was 70% (35/50; 95% CI, 55-82). All grade treatment-related adverse events (TRAEs) occurred in 88% of pts, including grade 3 in 32%, and grade 4 in 2% of pts. Diarrhea/colitis was the only grade 3/4 TRAE occurring in more than three pts (15% grade 3, 2% grade 4). The most common grade 3 TRAEs outside of diarrhea/colitis were fatigue (5%) and pyrexia (5%). There were no grade 5 TRAEs reported. Fifteen percent of pts had a TRAE leading to discontinuation of BOT alone and 12% had a TRAE leading to discontinuation of both BOT + BAL. Conclusions: In heavily pretreated metastatic MSS CRC pts, BOT + BAL continues to demonstrate promising clinical activity with durable responses and was well tolerated with no new immune-mediated safety signals. A larger pt set, analyses by subgroup, and additional translational data will be presented at the meeting. A randomized phase 2 trial in MSS CRC pts is enrolling (NCT05608044). Clinical trial information: NCT03860272 .

Priming of Sorafenib Prior to Radiofrequency Ablation Does Not Increase Treatment Effect in Hepatocellular Carcinoma

BACKGROUND

Preclinical studies have shown that modulation of the tumor microvasculature with anti-angiogenic agents decreases tumor perfusion and may increase the efficacy of radiofrequency ablation (RFA) in hepatocellular carcinoma (HCC). Retrospective studies suggest that sorafenib given prior to RFA promotes an increase in the ablation zone, but prospective randomized data are lacking.

AIMS

We conducted a randomized, double-blind, placebo-controlled phase II trial to evaluate the efficacy of a short-course of sorafenib prior to RFA for HCC tumors sized 3.5-7 cm (NCT00813293).

METHODS

Treatment consisted of sorafenib 400 mg twice daily for 10 days or matching placebo, followed by RFA on day 10. The primary objectives were to assess if priming with sorafenib increased the volume and diameter of the RFA coagulation zone and to evaluate its impact on RFA thermal parameters. Secondary objectives included feasibility, safety and to explore the relationship between tumor blood flow on MRI and RFA effectiveness.

RESULTS

Twenty patients were randomized 1:1. Priming with sorafenib did not increase the size of ablation zone achieved with RFA and did not promote significant changes in thermal parameters, although it significantly decreased blood perfusion to the tumor by 27.9% (p = 0.01) as analyzed by DCE-MRI. No subject discontinued treatment owing to adverse events and no grade 4 toxicity was observed.

CONCLUSION

Priming of sorafenib did not enhance the effect of RFA in intermediate sized HCC. Future studies should investigate whether longer duration of treatment or a different antiangiogenic strategy in the post-procedure setting would be more effective in impairing tumor perfusion and increasing RFA efficacy.

Use of MRI and Ga-68 DOTATATE for the detection of neuroendocrine liver metastases

PURPOSE

To compare detection rates of NET liver metastases of MRI and Ga-68-DOTATATE PET/CT to provide more clarity when selecting diagnostic imaging tests for NET staging.

METHODS

In this IRB-approved single-institution retrospective study, all patients with pathology-proven NET who underwent Ga-68-DOTATATE and MRI scans within 8 weeks of each other (3/2017-2/2020) were reviewed. Number of metastases for each patient on diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) MRI, and Ga-68 DOTATATE were recorded by two blinded radiologists, followed by consensus review with two separate blinded readers for MRI and nuclear medicine. Per-lesion and -modality scoring at each lesion location were then performed in consensus. Per-patient linear regression was performed comparing MRI and Ga-68 DOTATATE detection rates for each reader and in consensus, and per-lesion-matched pair difference means were used to compare detection frequency between modalities.

RESULTS

32 patients (mean age 59 years, 59.4% male) and 90 liver metastases were analyzed. Intraclass coefficients (ICC) [95% CI] between the two readers were 0.97 [0.95, 0.99], 0.89 [0.82, 0.94], and 0.98 [0.97, 0.99] for Ga-68 DOTATATE, DWI, and DCE, respectively. Matched per-lesion mean differences were + 0.17 ± 0.07 (p = 0.01) and + 0.22 ± 0.06 (p =  < 0.001) for DWI versus Ga-68 DOTATATE and DCE vs Ga-68 DOTATATE, respectively, favoring MRI. Case-based linear regressions estimate that DWI and DCE detect 1.28 [1.07, 1.49] and 1.33 [1.12, 1.54] lesions, respectively, for each one detected on Ga-68 DOTATATE.

CONCLUSION

MRI detects more hepatic NET metastasis in comparison to Ga-68 DOTATATE. Liver MRI should be performed in concert with Ga-68 DOTATATE in NET staging.

Large scale proteomics of circulating extracellular vesicles to reveal novel biomarkers for pancreatic cancer

523

Background: Robust biomarkers are urgently needed to assist in diagnosing pancreatic cancer. Earlier cancer diagnosis could increase survival rates by an estimated 5-fold and more reliable and real-time assessment of treatment effects in patients with cancer could improve quality of life and reduce healthcare costs. Isolation of circulating extracellular vesicles (cEVs) as ‘liquid biopsies’ offers an advantageous approach to diagnose and monitor disease status. Methods: We conducted a comprehensive proteomics study of cEVs from plasma samples to identify EV proteins that may be used as biomarkers for the diagnosis and prognosis of pancreatic cancer. Patients with pancreatic ductal adenocarcinoma (PDAC) of various tumor stages, chronic pancreatitis, intraductal papillary mucinous neoplasm (IPMN), and age-matched controls were enrolled. EVs were isolated directly from plasma samples using the affinity-based EVTrap method then subject to quantitation by liquid chromatography-tandem mass spectrometry. Results: A total of 124 patients (93 with PDAC, 12 with chronic pancreatitis, 8 with IPMN and 11 controls) were included in the discovery cohort. The isolation of EVs with EVtrap allowed the identification on average of 912 EV proteins per 100µL of sample. Principal component analysis of the cEV proteome showed clear separation between PDAC and benign pancreatic diseases. Individuals with IPMN were more closely related to controls, whereas chronic pancreatitis cases were more related to PDAC. At the functional level, we noted that cytokeratin, protein folding chaperons, and actin dynamics regulators were among protein clusters more highly altered in the cEV of patients with PDAC. We further identified new cEV markers associated with metastatic disease, such as PSMB4, RUVBL2, and ANKAR, as well as other EV proteins with strong correlation to prognosis, such as CRP, RALB, and CD55. Finally, we validated a 7-protein PDACEV signature in a validation cohort of 36 separate patients (24 with PDAC, 6 with chronic pancreatitis and 6 with IPMN) which yielded an 89% prediction accuracy for the diagnosis of PDAC. Conclusions: This study provides a valuable resource to the scientific community with a comprehensive catalog of novel proteins on circulating EVs that may assist in the development of novel biomarkers and improve the outcomes of patients with pancreatic cancer.

A Multi-step Approach to Adapting a Mind-Body Resiliency Intervention for Fear of Cancer Recurrence and Uncertainty in Survivorship (IN FOCUS)

BACKGROUND

For cancer survivors, there is a paucity of fear of recurrence (FOR) interventions that integrate empirically supported mind-body and psychological skills for managing FOR and are delivered in scalable formats.

OBJECTIVE

To adapt an evidence-based resiliency intervention to address FOR among cancer survivors.

METHODS

A multidisciplinary team of researchers, clinicians, and patient stakeholders followed an iterative intervention adaptation process (ORBIT). In Step 1, we sought to define key FOR management skills through a literature review and feedback from stakeholders. In Step 2, we integrated findings into a treatment manual and refined procedures for in-person delivery to groups of cancer survivors, defined as adults who had completed primary cancer treatment for non-metastatic cancer. In Step 3, we conducted a single arm trial to assess initial acceptability and change in FOR severity with 23 cancer survivors (N=4 intervention groups). In Step 4, we conducted additional qualitative interviews with 28 cancer survivors (N=6 focus groups stratified by FOR severity, N=15 individual interviews) to define adaptive and maladaptive strategies for coping with FOR and to identify preferences for delivery. In Step 5, we refined the treatment manual and procedures for testing in a future pilot randomized feasibility trial.

RESULTS

We identified critical feedback using a combination of qualitative and quantitative methods. The single arm trial suggested preliminary feasibility and sustained reductions in FOR severity, yet need for refinement (i.e., eligibility, delivery modality), prompting additional qualitative interviews for further targeting. The resulting intervention (IN FOCUS) is comprised of virtual, synchronous, group-delivered sessions that offer an integrated approach to FOR management by teaching cognitive-behavioral techniques, meditation, relaxation training, adaptive health behaviors, and positive psychology skills. Sessions are targeted by applying skills to FOR and associated healthcare engagement.

CONCLUSIONS

IN FOCUS is a targeted intervention for teaching mind-body resiliency skills to groups of cancer survivors with elevated FOR. Next steps are testing feasibility in a pilot randomized trial.

Organoid Sensitivity Correlates with Therapeutic Response in Patients with Pancreatic Cancer

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) remains a significant health issue. For most patients there are no options for targeted therapy and existing treatments are limited by toxicity. The HOPE trial (Harnessing Organoids for PErsonalized Therapy) was a pilot feasibility trial aiming to prospectively generate patient derived organoids (PDOs) from patients with PDAC and test their drug sensitivity and correlation with clinical outcomes.

EXPERIMENTAL DESIGN

PDOs were established from a heterogeneous population of patients with PDAC including both basal and classical PDAC subtypes.

RESULTS

A method for classifying PDOs as sensitive or resistant to chemotherapy regimens was developed to predict the clinical outcome of study subjects. Drug sensitivity testing on PDOs correlated with clinical responses to treatment in individual patients.

CONCLUSION

These data support the investigation of PDOs to guide treatment in prospective interventional trials in PDAC.

Neoadjuvant Yttrium-90 Transarterial Radioembolization with Resin Microspheres Prescribed Using the Medical Internal Radiation Dose Model for Intrahepatic Cholangiocarcinoma

PURPOSE

To evaluate outcomes of patients with intrahepatic cholangiocarcinoma (iCCA) undergoing neoadjuvant yttrium-90 (⁹⁰Y) transarterial radioembolization (TARE) with resin microspheres prescribed using the Medical Internal Radiation Dose (MIRD) model.

MATERIALS AND METHODS

This retrospective institutional review board-approved study included 37 patients with iCCA treated with ⁹⁰Y-TARE from October 2015 to September 2020. The primary outcome was overall survival (OS) from ⁹⁰Y-TARE. The secondary outcomes were progression-free survival (PFS), Response Evaluation Criteria In Solid Tumors 1.1 imaging response, and downstaging to resection. Patients with tumor proximity to the middle hepatic vein (<1 cm) and/or insufficient future liver remnant were treated with neoadjuvant intent (n = 21). Patients were censored at the time of surgery or at the last follow-up for the Kaplan-Meier survival analysis.

RESULTS

For 31 patients (69 years; interquartile range, 64-74 years; 20 men [65%]) included in the study, the first-line therapy was ⁹⁰Y-TARE for 23 (74%) patients. Imaging assessment at 6 months showed a disease control rate of 86%. The median PFS was 5.4 months (95% confidence interval [CI], 3-not reached). The PFS was higher after first-line ⁹⁰Y-TARE (7.4 months [95% CI, 5.3-not reached]) than that after subsequent ⁹⁰Y-TARE (2.7 months [95% CI, 2-not reached]) (P = .007). The median OS was 22 months (95% CI, 7.3-not reached). The 1- and 2-year OS rates were 60% (95% CI, 41%-86%) and 40% (95% CI, 19.5%-81%). In patients treated with neoadjuvant intent, 11 of 21 patients (52%) underwent resections. The resection margins were R0 and R1 in 8 (73%) and 3 (27%) of 11 patients, respectively. On histological review in 10 patients, necrosis of ≥90% tumor was achieved in 7 of 10 patients (70%).

CONCLUSIONS

First-line ⁹⁰Y-TARE prescribed using the MIRD model as neoadjuvant therapy for iCCA results in good survival outcome and R0 resection for unresectable patients.

Effect of High-Dose vs Standard-Dose Vitamin D3 Supplementation on Body Composition among Patients with Advanced or Metastatic Colorectal Cancer: A Randomized Trial

Simple Summary

Skeletal muscle and adipose tissue express the vitamin D receptor and may be a mechanism through which vitamin D supplementation slows cancer progression and reduces cancer death. It is unknown if high-dose vitamin D₃ impacts skeletal muscle and adipose tissue, as compared with standard-dose vitamin D₃, in patients with advanced or metastatic colorectal cancer. In this exploratory analysis of a phase II randomized trial, high-dose vitamin D₃ did not lead to changes of body weight, body mass index, muscle area, muscle attenuation, visceral adipose tissue area, or subcutaneous adipose tissue area, as compared with standard-dose vitamin D₃. High-dose vitamin D₃ did not change body composition in patients receiving chemotherapy for advanced or metastatic colorectal cancer.

Abstract

Skeletal muscle and adipose tissue express the vitamin D receptor and may be a mechanism through which vitamin D supplementation slows cancer progression and reduces cancer death. In this exploratory analysis of a double-blind, multicenter, randomized phase II clinical trial, 105 patients with advanced or metastatic colorectal cancer who were receiving chemotherapy were randomized to either high-dose vitamin D₃ (4000 IU) or standard-dose (400 IU) vitamin D₃. Body composition was measured with abdominal computed tomography at enrollment (baseline) and after cycle 8 of chemotherapy (16 weeks). As compared with standard-dose vitamin D₃, high-dose vitamin D₃ did not significantly change body weight [−0.7 kg; (95% CI: −3.5, 2.0)], body mass index [−0.2 kg/m²; (95% CI: −1.2, 0.7)], muscle area [−1.7 cm²; (95% CI: −9.6, 6.3)], muscle attenuation [−0.4 HU; (95% CI: −4.2, 3.2)], visceral adipose tissue area [−7.5 cm²; (95% CI: −24.5, 9.6)], or subcutaneous adipose tissue area [−8.3 cm²; (95% CI: −35.5, 18.9)] over the first 8 cycles of chemotherapy. Among patients with advanced or metastatic colorectal cancer, the addition of high-dose vitamin D₃, vs standard-dose vitamin D₃, to standard chemotherapy did not result in any changes in body composition.

Self-guided behavioral skills training: A public health approach to promoting nurturing care environments

The World Health Organization identified the promotion of "Nurturing Care Environments" as a global health priority. Responsive caregiving, 1 of 5 domains describing nurturing care, is critical for healthy child development. Relatively little research has evaluated population-level interventions aimed to increase responsive caregiving during the first 1,000 days of an infant's life. In this pilot study, we evaluated an intervention designed for population-level dissemination that targeted responsive caregiving. The self-guided behavioral skills training aimed to teach mothers to imitate infant vocalizations. The intervention was delivered within an on-line asynchronous training. All 3 mothers increased vocal imitative behavior following training without receiving coaching or behavior-specific feedback from an implementer. The results offer a preliminary proof of concept with implications for population-level intervention design and evaluation.

Randomized Phase III Trial of Pegvorhyaluronidase Alfa With Nab-Paclitaxel Plus Gemcitabine for Patients With Hyaluronan-High Metastatic Pancreatic Adenocarcinoma

PURPOSE

To evaluate the efficacy and safety of pegvorhyaluronidase alfa (PEGPH20) plus nab-paclitaxel/gemcitabine (AG) in patients with hyaluronan-high metastatic pancreatic ductal adenocarcinoma (PDA).

PATIENTS AND METHODS

HALO 109-301 was a phase III, randomized, double-blind, placebo-controlled study. Patients ≥ 18 years of age with untreated, metastatic, hyaluronan-high PDA were randomly assigned 2:1 to PEGPH20 plus AG or placebo plus AG. Treatment was administered intravenously in 4-week cycles (3 weeks on, 1 week off) until progression or intolerable adverse events: PEGPH20 3.0 µg/kg twice per week for cycle 1 and once per week thereafter; nab-paclitaxel 125 mg/m² once per week; and gemcitabine 1,000 mg/m² once per week. The primary end point was overall survival (OS); secondary end points included progression-free survival (PFS), objective response rate (ORR), and safety. Response was independently assessed per RECIST v1.1.

RESULTS

At data cutoff, 494 patients were randomly assigned, with 492 (327 for PEGPH20 and 165 for placebo) included in intention-to-treat analyses. Baseline characteristics were balanced for PEGPH20 plus AG versus placebo plus AG. There were 330 deaths, with a median OS of 11.2 months for PEGPH20 plus AG versus 11.5 months for placebo plus AG (hazard ratio [HR], 1.00; 95% CI, 0.80 to 1.27; P = .97); median PFS was 7.1 months versus 7.1 months (HR, 0.97 [95% CI, 0.75 to 1.26]); ORR was 47% versus 36% (ORR ratio, 1.29 [95% CI, 1.03 to 1.63]). Grade ≥ 3 adverse events with a ≥ 2% higher rate with PEGPH20 plus AG than with placebo plus AG included fatigue (16.0% v 9.6%), muscle spasms (6.5% v 0.6%), and hyponatremia (8.0% v 3.8%).

CONCLUSION

The addition of PEGPH20 to AG increased the ORR but did not improve OS or PFS. The safety profile of PEGPH20 plus AG was consistent with that found in previous studies. These results do not support additional development of PEGPH20 in metastatic PDA.

Phase 1b study of a small molecule antagonist of human chemokine (C-C motif) receptor 2 (PF-04136309) in combination with nab-paclitaxel/gemcitabine in first-line treatment of metastatic pancreatic ductal adenocarcinoma

Background In pancreatic ductal adenocarcinoma (PDAC), the chemokine (C-C motif) ligand 2 (CCL2)/chemokine (C-C motif) receptor 2 (CCR2) axis plays a key role in immunosuppressive properties of the tumor microenvironment, patient prognosis, and chemoresistance. This phase Ib study assessed the effects of the orally administered CCR2 inhibitor PF-04136309 in combination with nab-paclitaxel and gemcitabine in patients with previously untreated metastatic PDAC. Methods Patients received PF-04136309 twice daily (BID) continuously plus nab-paclitaxel (125 mg/m2) and gemcitabine (1000 mg/m2) administered on days 1, 8, and 15 of each 28-day cycle. The primary objectives were to evaluate safety and tolerability, characterize dose-limiting toxicities (DLTs), and determine the recommended phase II dose (RP2D) of PF-04136309. Results In all, 21 patients received PF-04136309 at a starting dose of 500 mg or 750 mg BID. The RP2D was identified to be 500 mg BID. Of 17 patients treated at the 500 mg BID starting dose, three (17.6%) experienced a total of four DLTs, including grade 3 dysesthesia, diarrhea, and hypokalemia and one event of grade 4 hypoxia. Relative to the small number of patients (n = 21), a high incidence (24%) of pulmonary toxicity was observed in this study. The objective response rate for 21 patients was 23.8% (95% confidence interval: 8.2-47.2%). Levels of CD14 + CCR2+ inflammatory monocytes (IM) decreased in the peripheral blood, but did not accumulate in the bone marrow. Conclusions PF-04136309 in combination with nab-paclitaxel plus gemcitabine had a safety profile that raises concern for synergistic pulmonary toxicity and did not show an efficacy signal above nab-paclitaxel and gemcitabine. ClinicalTrials.gov identifier: NCT02732938.

Association of immune related adverse events with superior outcomes in patients with hepatocellular carcinoma (HCC) treated with nivolumab

e16630

Background: Nivolumab, an anti-PD1 antibody, is FDA approved in patients (pts) with HCC. Anti-PD-1 promotes hyperstimulation of host immunity and is associated with a spectrum of toxicities known as immune-related adverse events (irAEs). In other malignancies, higher rates of irAEs are associated with improved cancer outcomes. This study shows correlation between irAEs and efficacy in pts with HCC treated with nivolumab. Methods: Demographic and toxicity data were collected retrospectively on all pts with HCC treated with nivolumab at a single institution from Jan 2012 – Sept 2019. Response was evaluated using RECISTv1.1. Adverse events were assessed according to CTCAEv5.0. Categorical variables were assessed by Fisher's exact test. Survival was estimated with the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate analyses were performed by the Cox-regression model. Results: 30 pts were treated; irAEs were detected in 16 (53%). There was no difference in baseline characteristics among those who did and did not experience irAEs (Table). The most frequent irAEs were elevated AST/ALT (n = 7; 44%), rash (n = 4; 25%), and hypothyroid (n = 4; 25%). 3 G3 (rash and transaminitis) and 1 G4 AE (pured red cell apalasia) were observed. Among all pts, overall response rate (RR) and disease control rate (DCR) were 13 and 50%, respectively. Median progression free survival (PFS) and overall survival (OS) were 27 and 56 weeks (w), respectively. The RR and DCR were higher among irAEs vs non-irAEs, although this did not reach statistical significance (RR 25 vs 0%; p = 0.05; DCR 62 vs 35%; p = 0.19). Median PFS and OS were longer in those with irAEs vs non-irAE; PFS 33 vs 16 w (HR: 0.26; CI 95%: 0.076-0.89; p = 0.028); (OS 69 vs 21 w HR: 0.18; CI 95%: 0.05-0.58; p = 0.002). On multivariate analysis, viral etiology was associated with prolonged PFS (p = 0.002) and MELD was associated with reduced OS (p = 0.004). Conclusions: Development of irAEs was associated with prolonged PFS and OS in pts with HCC treated with nivolumab. Further study is needed to determine whether type of irAE, onset time, or duration affect cancer outcomes. [Table: see text]

GI oncology molecular tumor board: Fostering collaboration and clinical education for personalized therapy

11029

Background: In recent years, genomic profiling has become standard of care for several gastrointestinal (GI) cancers. In addition to standard of care indications, comprehensive genomic profiling has led to novel and expanded applications of targeted therapy, chemotherapy, and immunotherapy and facilitated identification of potential clinical trials. A GI molecular tumor board (MTB) was developed with a goal of improving understanding of the biological effects of genomic alterations and their therapeutic implications to enhance personalized therapy. Methods: Foundation Medicine (FM) collaborated with physicians in the GI oncology group of an academic medical center to develop a GI MTB starting March 2019. As of December 2019, 27 GI oncology cases were presented where FoundationOneCDx testing was performed and a clinical question was posed. Cases were discussed by faculty, fellows, research staff, and a clinical genomic scientist and oncologist from FM. Impacted signaling pathways and biomarkers were discussed for each case alongside clinical content so that physicians could consider therapeutic options and clinical trials. Presenting faculty were asked to complete a questionnaire for each case presented to assess the impact of the MTB discussion on clinician knowledge and patient-level treatment recommendations. Results: Of 27 questionnaires sent to 7 providers, 17 (63%) were completed. Respondents indicated that as a result of the MTB, the treatment plan was changed in 2 cases (12%), reinforced in 9 cases (53%) and in 6 cases (35%) there was no effect. On a Likert scale of 1-4 where 1 is “rare/poorly” and 4 is “great” mean scores were as follows: Did this MTB help you understand the biological effects of the main genomic alteration(s) reported in the case presented? 3.3. Did this MTB help you understand the possible therapeutic implications of the main genomic alterations in the case presented? 3.3. Did this MTB improve your understanding of the role of next generation sequencing and comprehensive genomic profiling in making treatment decisions? 3.4. Conclusions: The results of our questionnaire indicate that treatment decisions were changed in a minority of cases based on the MTB. In most cases, clinical decision making was reinforced and understanding of the biological effects of genomic alterations and their therapeutic implications were improved. Based on this feedback we will continue to refine and integrate the GI MTB into clinical care for patients with GI malignancies, and share our experience locally with other disease groups.

AGEN1181, a clinical stage Fc-engineered anti-CTLA-4 antibody with improved therapeutic potential for the treatment of patients with advanced malignancies

TPS3157

Background: AGEN1181 is a novel Fc-optimized anti-CTLA4 antibody, currently being evaluated in an ongoing multi-center, open-label, phase 1 study in all advanced solid tumors as mono-therapy and combination with anti-PD-1 antibody, AGEN2034 (NCT03860272). AGEN1181 is Fc-engineered to harness a novel mechanism for enhanced FcγR-dependent functionality relative to first-generation CTLA-4 antibodies. In pre-clinical models, AGEN1181 enhances T cell priming, depletion of intratumoral regulatory T cells (Treg) and improved memory formation compared to first-generation anti-CTLA-4 antibodies. Most notably, AGEN1181 demonstrates improved binding to FcyRIIIA and superior T cell responsiveness in populations that only express the low affinity FcγRIIIA receptor relative to first-generation IgG1 CTLA-4 antibodies. The combination of AGEN1181 and AGEN2034 further enhances T cell activation and effector function. Methods: This phase 1 study is an open-label, multi-center dose-escalation designed to evaluate the safety, tolerability, dose limiting toxicity (DLT) PK, and pharmacodynamic profiles of patients with refractory advanced solid tumors who did not receive an anti-CTLA4 previously. The study is being conducted in 3 arms; with patients assigned using a standard 3+3 dose escalation design in the mono-therapy arms with AGEN1181 and an accelerated design in the combination with AGEN2034 arm. AGEN1181 is administered as IV infusion as mono-therapy on Day 1 of every 3 weeks (0.1,0.3,1,2,4 mg/kg), every 6-weeks (1,2,4 mg/kg) in parallel cohorts and every 6-weeks (0.1,0.3,1,2,4 mg/kg) in combination with AGEN2034 (3mg/kg Q2Weeks) until disease progression or unacceptable toxicity (maximum 2 years). All 3 Arms are open and enrolling patients. The study is expected to enroll approximately 80 evaluable patients with solid tumors. Dose reductions are not allowed in the event of AGEN1181-related toxicities. Currently 3 cohorts have been completed, first cohort in the combination arm and the fourth cohort in the monotherapy arm are enrolling. Preclinical and clinical assessment of AGEN1181 supports continued development as a potential therapy for refractory or relapsed advanced solid tumors. Clinical trial information: NCT03860272 .

Safety and efficacy of chemotherapy in older adults with locally advanced and metastatic pancreatic ductal adenocarcinoma (PDAC)

654

Background: PDAC is often diagnosed in patients (pts) ≥75yrs. However, older adults comprise a small proportion of subjects in prospective trials, and there is little reported on the safety and efficacy of chemotherapy in this population. Methods: Records were reviewed on all pts ≥75yrs treated with chemotherapy for locally advanced and metastatic PDAC at a single institution from April 2010 - March 2018. Response rate (RR), progression free survival (PFS), overall survival (OS) and toxicities were compared among the different regimens, and among pts < or ≥80yrs. Survival was estimated with the Kaplan-Meier method and compared by log-rank test. Univariate analyses were performed by Fisher’s exact test and multivariate analyses by a Cox-regression model to identify factors associated with PFS and OS in this population. Results: 67 pts were treated, median age 81yrs (range: 75-90), stage III (34, 51%) and IV (33, 49%). Chemotherapy regimens included: gemcitabine alone (39), gemcitabine/nab-paclitaxel (17), gemcitabine/vinorebine (1), FOLFOX (8) and FOLFIRINOX (2). 59 (88%) pts required dose adjustments due to toxicity; no differences by age or regimen. RR, PFS, and OS did not differ by age or regimen (Table), although sample size was small. Age >80yrs was associated with reduced PFS (p 0.03). On univariate analyses liver metastases and performance status (PS)>1 were associated with reduced OS; PS>1 was associated with reduced OS on multivariate analysis. Conclusions: Among pts with locally advanced and metastatic PDAC ≥75yrs, there were no differences in RR, PFS or OS by chemotherapy regimen. PS was the only variable associated with reduced OS. Older adults with PS 0-1 are likely to benefit from chemotherapy for non-resectable PDAC.[Table: see text]

Treatment burden following standard of care open versus robotic D2 gastrectomy plus neoadjuvant chemotherapy (NAC) for locally advanced gastric cancer (LAGC)

303

Background: Phase III trials demonstrate improved short-term outcomes after laparoscopic gastrectomy for LAGC compared to open. We hypothesized that robotic D2 gastrectomy after NAC (NAC/RG) yields benefits across multiple outcome domains vs standard of care treatment for LAGC. Methods: Single institution, interrupted time series comparing SOC plus open gastrectomy (OG,2008-2013) for LAGC (T2-4Nany/TanyN+) vs universal neoadjuvant plus RG (2013-2018). Treatment burden was a composite of adverse events affecting: efficiency (postoperative length of stay, reoperation or 90 d readmission), oncology (positive margins, < 16 resected nodes), cumulative major morbidity (90 d comprehensive complication index) and pain (narcotic consumption). Predictors were evaluated via multivariate modeling, and 2-year overall survival was estimated by Kaplan-Meier/log-rank tests. Results: After exclusions, 87 subjects underwent surgical resection (55 OG; 32 RG) with equivalent baseline characteristics: demographics, BMI, comorbidity (Charlson), tumor size, and clinical AJCC staging; male sex was more likely in RG (69% vs. 44%, p = 0.02). NAC administration increased from 35% in SOC/OG cohort to 100% in NAC/RG. All four domains of efficiency, oncologic efficacy, morbidity, and pain (narcotic use) improved. Treatment burden declined from 86% in OG to 56% after RG (p = 0.003). Multivariable modeling demonstrated OR 0.23 for treatment burden in RG compared to OG (95% CI 0.07-0.72, p = 0.012), whereas sex, extent of resection (total vs subtotal), tumor size, and T stage had no effect. These differences persisted in NAC subgroup (n = 51) comparisons between RG and OG treatment burden, as well as pathologic T stage, tumor size, and AJCC stage. No detriment in 2-year overall survival was observed after adoption of NAC/RG (80% RG vs. SOC 60%, p = 0.048). Conclusions: After NAC, robot-assisted D2 gastrectomy was associated with decreased treatment burden relative to OG. Frequencies of unfavorable hospitalization, adverse oncological outcomes, major morbidity, and narcotic consumption all improved after RG in this interrupted time series. Prospective trials are needed.

Analysis of OX40 agonist antibody (PF-04518600) in patients with hepatocellular carcinoma

523

Background: PF-04518600 (PF-8600) is a humanized agonist IgG2 monoclonal antibody to the tumor necrosis factor superfamily receptor OX40. PF-8600 was given to patients (pts) with advanced/metastatic hepatocellular carcinoma (HCC) in dose expansion of a phase 1 study (NCT02315066). Safety and tolerability were primary endpoints and exploratory endpoints included biomarker analyses. Methods: Pts received either 30 mg (Arm 1) or 250 mg (Arm 2) of PF-8600 intravenously Q2W. Pts had pathologic diagnosis of advanced HCC, a Child-Pugh score of A or B7, and had ≤2 prior lines of therapy, or if treatment naïve, had declined standard of care. Radiological tumor assessments were conducted Q8W. Biopsy samples collected at baseline and wk 6 were analyzed by immunohistochemistry and RNA sequencing for pharmacodynamic (PD) analyses. Whole blood samples were collected longitudinally for DNA extraction for high-throughput sequencing of the T cell receptor β-chain. Results: Arm 1 enrolled 16 pts (mean age 65.6 yrs; range 54-81 yrs; prior PD-1/PD-L1: 5 pts) and Arm 2 enrolled 19 pts (mean age 61.7 yrs; range 26-79 yrs; prior PD-1/PD-L1: 3 pts). All grade treatment related adverse events (TRAEs) occurred in 69% of pts in Arm 1 and 58% of pts in Arm 2. The rate of ≥Grade 3 TRAEs was 31% and 16% in Arms 1 and 2, respectively. For both arms combined, the most common (≥10%) TRAEs were rashes and pruritus. In Arm 1, 8 pts (50%) and in Arm 2, 10 pts (53%) achieved stable disease (SD), with a mean duration of 18.4 (range: 14.0-30.3 wks) and 17.4 wks (range: 8.0-31.9 wks), respectively. PD effects were more evident in Arm 1 than Arm 2, including increased OX40 tumor expression and positive changes in gene signatures, reflecting an active anti-tumor immune response. Conclusions: PF-8600 was generally well tolerated and provided meaningful disease control. While safety and efficacy were not significantly different between the 2 doses, there were potential differences in the PD data. The safety and relative durability of SD in HCC pts may provide a rationale for exploration of combination therapy in this pt population. Clinical trial information: NCT02315066.

HALO 109-301: A randomized, double-blind, placebo-controlled, phase 3 study of pegvorhyaluronidase alfa (PEGPH20) + nab-paclitaxel/gemcitabine (AG) in patients (pts) with previously untreated hyaluronan (HA)-high metastatic pancreatic ductal adenocarcinoma (mPDA)

638

Background: HA is a major component of the tumor microenvironment (TME) in PDA. PEGPH20 degrades tumor HA, remodeling the TME. In PDA models, PEGPH20 has shown antitumor activity and increased TME delivery of anticancer agents to improve efficacy. A randomized phase 2 study showed promising results for PEGPH20+AG (PAG) in mPDA and identified HA accumulation as a biomarker. We present results from a phase 3 study (NCT02715804) of PAG for pts with HA-high mPDA. Methods: Pts ≥18 years with untreated HA-high mPDA were randomized (stratified by geographic region) 2:1 to PAG or placebo+AG (AG). HA status was prospectively determined with VENTANA HA RxDx Assay, with HA-high defined as ≥50% staining of a tumor sample. Treatment was administered IV in 4-wk cycles (3 wks on, 1 wk off) until progression or intolerable adverse events (AEs): PEGPH20 3.0 µg/kg twice wkly for Cycle 1 and once wkly (QW) thereafter, A 125 mg/m2 QW and G 1000 mg/m2 QW. Prophylactic enoxaparin 1 mg/kg was given daily for thromboembolism (TE) risk. The primary endpoint was overall survival (OS); secondary endpoints included progression-free survival (PFS), objective response rate (ORR) and safety. Response was independently assessed per RECIST v1.1. The estimated sample size was ~500 pts to detect a hazard ratio (HR) for OS of 0.67 (93% power, 2-sided α = 0.05) after 330 deaths. Results: As of 20 May 2019, 494 pts were randomized with 492 (327 for PAG and 165 for AG) included in ITT analyses (2 pts excluded due to site violations). Baseline characteristics were balanced for PAG vs AG. After 330 deaths, median OS for PAG vs AG was 11.2 vs 11.5 mo (HR 1.00, 95% CI 0.80–1.27; P = 0.97); median PFS was 7.1 vs 7.1 mo (HR 0.97, 95% CI 0.75–1.26); confirmed ORR was 34% vs 27%. Grade (G) 3+ AEs (PAG vs AG) included neutropenia (44% vs 47%), thrombocytopenia (21% vs 16%) and fatigue (16% vs 10%); G3+ rates were 6% vs 7% for TE events, 5% vs 2% for bleeding events and 13% vs 5% for musculoskeletal events. Conclusions: PAG did not improve clinical outcomes vs AG. The PAG safety profile was consistent with that of previous studies. Clinical trial information: NCT02715804.

Abstract B005: A phase I study of A166, a novel anti-HER2 antibody-drug conjugate (ADC), in patients with locally advanced/metastatic solid tumors

A Phase I study of A166, a Novel Anti-HER2 Antibody-Drug Conjugate (ADC), in Patients with Locally Advanced/Metastatic Solid Tumors. Purpose: A166 is an Antibody Drug Conjugate (ADC) targeting HER2-expressing cancer cells, aiming for post trastuzumab/TDM1 population and patients with HER2 expressing cancers not commonly treated with trastuzumab and TDM1. The antibody has the same amino acid sequence as trastuzumab, and it is designed to provide uniform distribution of payload molecules, using an innovative antibody-drug linker and duostatin-5 (an MMAF derivative) as payload. This ongoing phase I, open-label, first-in-human study is evaluating the safety, pharmacokinetics (PK), and dose-limiting toxicities (DLT) of A166 to determine the Maximum-Tolerated Dose (MTD) and/or recommended phase II dose (RP2D). Methods: Patients with advance solid tumors received escalating doses of A166 (0.3, 1.2, 3.6, and 4.8 mg/kg), administered intravenously (IV) every three weeks. Patients must have had documented HER2 positivity defined as positive, or amplified on in situ hybridization (ISH) or next-generation sequencing (NGS), or HER2 expression, defined as at least 1+ by validated immunohistochemistry (IHC) test or an activating HER2 mutation. Dose escalations were guided by a Bayesian logistic regression model (BLRM). Assessments include archival tumor molecular status, PK, and efficacy by Response Evaluation Criteria in Solid Tumors (RECIST). Results: 23 subjects [median age 68 (range 50-83), 17 female, 6 male, PS 0-1], have been treated. All patients had metastatic disease: 7 breast, 7 GC/GEJ/EC; 4 CRC, 5 other (lacrimal gland, vulvar, bladder, NSCLC, and ovarian). HER2 expression was available for all 23 patients: 12 (3+), 2 (2+ and amplified), 7 (amplified), 1 (1+), and 1 (HER2 mutated), and most had received previous HER2 targeted therapies (1-7 lines). No significant &gt; Grade 3 AEs at doses below 3.6 mg/kg have been observed. Based on safety and efficacy outcomes, dose levels (DLs) 3.6 and 4.8 mg/kg were expanded to a total of 7 and 8 patients respectively. In these two cohorts, 4 patients experienced grade 2 ophthalmic toxicities involving the ocular surface (3 keratitis, 1 blurred vision), and 2 had Grade 3 keratitis. Treatment was discontinued (n=3) or delayed (n=3), and patients were treated with topical steroids and aggressive lubrication. All patients have resolved/resolving status of the ophthalmic toxicities, with a duration from onset to recovery/improvement of symptoms of 2-3 weeks. Other common drug-related and reversible Grade 1-2 AEs include blurry vision (n=4), peripheral neuropathy (n=3), anemia (n=2), leukopenia (n=2), thrombocytopenia (n=2). No cardiac or liver toxicities have been noted. Preliminary response assessment found that efficacy is evident at DL 3.6 and 4.8 mg/kg. Of 8 evaluable patients at 3.6-4.8 DL, 4/8 had PR, and 6/8 had DCR. Among PRs, 3 had prior anti-HER2 therapies, including 2/3 with prior TDM1. Conclusion: A166 has been well tolerated and shows promising anti-tumor activity in patients with heavily pre-treated HER2-positive cancers. The ophthalmic AEs have been reversible and manageable with supportive management. A detailed regimen for early diagnosis and intervention has been developed to further investigate the management of these toxicities in future cohorts, and three additional dose levels (6.0, 7.2, 8.4 mg/kg) will be added to the escalation phase.

Citation Format: Diana M Lopez, Minal Barve, Judy Wang, Andrea J. Bullock, Eirini Pectasides, Ulka Vaishampayan, Alexander I. Spira, Susanna Ulahannan, Amita Patnaik, Rachel E. Sanborn, Dragan Cicic, Qiuqing Ang, Gregory Bergonio, Jordi Rodon Ahnert. A phase I study of A166, a novel anti-HER2 antibody-drug conjugate (ADC), in patients with locally advanced/metastatic solid tumors [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B005. doi:10.1158/1535-7163.TARG-19-B005

Chronic intestinal pseudo-obstruction in a patient with metastatic gastro-oesophageal junction cancer receiving treatment with pembrolizumab

Acute gastrointestinal (GI) immune-related adverse events (irAE) are commonly reported by patients with cancer undergoing treatment with immune checkpoint inhibitors (CPI); however chronic irAEs are rare. We present a case of a 71-year-old woman with metastatic gastro-oesophageal junction (GOJ) adenocarcinoma who developed delayed-onset chronic intestinal pseudo-obstruction (CIPO) while receiving second-line pembrolizumab. Repeated CT scans of the abdomen/pelvis found no small bowel obstruction, and evaluations for bowel inflammation, infection and paraneoplastic syndrome were negative. Bowel rest and glucocorticoids were associated with transient symptom resolution; however, symptoms recurred within 1 month. The patient was ultimately supported with total parenteral nutrition and intestinal motility agents. After 4 months, the GOJ cancer remained stable with no signs of progression. As CPI use expands, the incidence of rare irAEs, such as CIPO, may increase.

Angiogenic Factor and Cytokine Analysis among Patients Treated with Adjuvant VEGFR TKIs in Resected Renal Cell Carcinoma

PURPOSE

The use of VEGFR TKIs for the adjuvant treatment of renal cell carcinoma (RCC) remains controversial. We investigated the effects of adjuvant VEGFR TKIs on circulating cytokines in the ECOG-ACRIN 2805 (ASSURE) trial.

EXPERIMENTAL DESIGN

Patients with resected high-risk RCC were randomized to sunitinib, sorafenib, or placebo. Plasma from 413 patients was analyzed from post-nephrectomy baseline, 4 weeks, and 6 weeks after treatment initiation. Mixed effects and Cox proportional hazards models were used to test for changes in circulating cytokines and associations between disease-free survival (DFS) and cytokine levels.

RESULTS

VEGF and PlGF increased after 4 weeks on sunitinib or sorafenib (P < 0.0001 for both) and returned to baseline at 6 weeks on sunitinib (corresponding to the break in the sunitinib schedule) but not sorafenib (which was administered continuously). sFLT-1 decreased after 4 weeks on sunitinib and 6 weeks on sorafenib (P < 0.0001). sVEGFR-2 decreased after both 4 and 6 weeks of treatment on sunitinib or sorafenib (P < 0.0001). Patients receiving placebo had no significant changes in cytokine levels. CXCL10 was elevated at 4 and 6 weeks on sunitinib and sorafenib but not on placebo. Higher baseline CXCL10 was associated with worse DFS (HR 1.41 per log increase in CXCL10, Bonferroni-adjusted P = 0.003). This remained significant after adjustment for T-stage, Fuhrman grade, and ECOG performance status.

CONCLUSIONS

Among patients treated with adjuvant VEGFR TKIs for RCC, drug-host interactions mediate changes in circulating cytokines. Elevated baseline CXCL10 was associated with worse DFS. Studies to understand functional consequences of these changes are under way.

Real-world assessment of healthcare costs for patients with metastatic pancreatic cancer following first-line chemotherapy initiation

e15710

Background: Nab-paclitaxel-gemcitabine (AG) and FOLFIRINOX (FFX) are commonly used regimens for the treatment of metastatic pancreatic cancer (mPDA). This descriptive study aimed to report total healthcare costs following first line (1L) exposure to AG/FFX among patients with mPDA. Methods: Retrospective cohorts of 1L AG and FFX initiators with mPDA were constructed from the MarketScan database (study period 2014-2017). The index date was the date of 1L AG or FFX initiation. Included patients had continuous insurance enrollment. Total healthcare costs (outpatient, inpatient, emergency department, chemotherapy, pharmacy) were assessed at 0-1, 0-3, 0-6, and 0-12 months post-index among patients who remained uncensored (using the last claim date) through the last month of each follow-up interval. Results: 2199 patients initiated AG (N=1352) or FFX (N=847) as their 1L regimen. Compared with AG initiators, FFX patients were younger (59 vs 63 years) and had better baseline health status (FFX/AG): diabetes 43%/57%; cerebrovascular disease 21%/27%. Median time to censoring was 5.4 (AG) and 7.2 (FFX) months. Median treatment duration was 2.1 (AG) and 2.3 (FFX) months. FFX costs were higher than AG costs during each follow-up interval, with the cost differential increasing over time (Table). Conclusions: Higher total healthcare costs were observed for patients with mPDA who initiated 1L FFX compared with 1L AG. Further research using comparative methodology is warranted to fully elucidate these findings and understand cost drivers. [Table: see text]

Exposure-response (E-R) analysis of efficacy of pegvorhyaluronidase alfa (PEGPH20) in combination with nab-paclitaxel + gemcitabine (AG) in patients (Pts) with metastatic pancreatic ductal adenocarcinoma

e15746

Background: PEGPH20 depolymerizes extracellular matrix hyaluronan (HA) and is an investigational agent for the treatment of pts with HA-accumulating tumors. HALO-109-202 (260 pts) was conducted to evaluate the effect of PEGPH20 + AG in pts with mPDA. Methods: E-R models were developed to evaluate the relationship between PEGPH20 exposure and efficacy, including time to PFS, time to OS, and overall response (OR). Results: The final E-R PFS model was a Cox proportional hazards model that included effects of PEGPH20 Cmax and baseline tumor biopsy HA (high or low). Higher PEGPH20 Cmax was associated with a lower risk of radiological progression. Pts with baseline HA≥ 50% (HA-high) tumor biopsy were at a lower risk of radiological progression with PEGPH20 treatment. A similar E-R model evaluated the effect of PEGPH20 on OS, including effects of dose-adjusted PEGPH20 concentration 7 days postdose (D7 Conc), liver metastases, and baseline tumor burden. The model-predicted influence of PEGPH20 D7 Conc on risk of death indicated that with increasing PEGPH20 D7 Conc, the predicted risk of death decreases. Pts with liver metastases and higher baseline tumor burden were predicted to have a higher risk of death. The final E-R efficacy model for OR probability was a linear function of dose-adjusted PEGPH20 AUC in Cycle 1, where increasing exposure was related to a higher predicted OR probability. Conclusions: The E-R analyses demonstrate that improvements in PFS and OS with PEGPH20 + AG is PEGPH20 exposure-dependent, supporting 3 µg/kg as an appropriate dose for further development and emphasizing the need for sufficient PEGPH20 exposure for improved therapeutic effect. Clinical trial information: NCT01839487. [Table: see text]

A phase I open label study evaluating VT1021 in patients with advanced solid tumors

TPS3158

Background: VT1021 is a cyclic pentapeptide that functions as a potent inducer of thrombospondin-1 (Tsp-1) expression in the tumor microenvironment (TME). By triggering the production of Tsp-1, VT1021 reprograms the TME from one that is immune-suppressive and tumor-promoting, to one that activates the adaptive immune system and is tumor-inhibiting. Tsp-1 reprograms the TME to: (i) induce apoptosis in tumor cells that express CD36 on their cell surface, (ii) convert macrophages from M2 to M1 polarization, which promotes phagocytosis and blunts immunosuppression and (iii) inhibit angiogenesis. Preclinical studies have shown robust anti-tumor activities of VT1021 in animal models of ovarian, pancreatic and breast cancer, including complete tumor regression and reprogramming of the immune TME. These observations led to the initiation of the first-in-human study of VT1021. Methods: This study is a first-in-human, Phase 1, open-label, multicenter, dose escalation (Part 1) study with dose expansion (Part 2) in advanced solid tumors. The primary objectives are to assess the safety and tolerability of VT1021, to assess dose-limiting toxicities (DLT), and to determine the maximum tolerated dose (MTD) and the recommended Phase 2 dose (RP2D). Secondary objectives include the evaluation of pharmacokinetics (PK) and pharmacodynamic (PD) effects of VT1021 in tumor and tumor microenvironment, and assessment of preliminary antitumor activity. VT1021 is administered intravenously twice weekly. DLTs will be assessed in the first cycle (Days 1-28) of the dose escalation cohort and are defined as grade 3 adverse events related to VT1021. In Part 1 of the study, 24-30 patients will be enrolled to determine the MTD and RP2D for expansion. In Part 2 of the study, 80-100 patients will be enrolled, grouped into cohorts based on disease subtypes (ovarian, pancreatic, Triple-negative breast cancers, and glioblastoma). Blood samples and biopsy samples from patients will be collected to assess PK properties and PD responses systemically as well as in the TME. No formal statistical hypothesis testing will be conducted in this study. This study is currently open for enrollment in the US. Clinical trial information: NCT03364400.

Effect of High-Dose vs Standard-Dose Vitamin D3 Supplementation on Progression-Free Survival Among Patients With Advanced or Metastatic Colorectal Cancer: The SUNSHINE Randomized Clinical Trial

IMPORTANCE

In observational studies, higher plasma 25-hydroxyvitamin D (25[OH]D) levels have been associated with improved survival in metastatic colorectal cancer (CRC).

OBJECTIVE

To determine if high-dose vitamin D3 added to standard chemotherapy improves outcomes in patients with metastatic CRC.

DESIGN, SETTING, AND PARTICIPANTS

Double-blind phase 2 randomized clinical trial of 139 patients with advanced or metastatic CRC conducted at 11 US academic and community cancer centers from March 2012 through November 2016 (database lock: September 2018).

INTERVENTIONS

mFOLFOX6 plus bevacizumab chemotherapy every 2 weeks and either high-dose vitamin D3 (n = 69) or standard-dose vitamin D3 (n = 70) daily until disease progression, intolerable toxicity, or withdrawal of consent.

MAIN OUTCOMES AND MEASURES

The primary end point was progression-free survival (PFS) assessed by the log-rank test and a supportive Cox proportional hazards model. Testing was 1-sided. Secondary end points included tumor objective response rate (ORR), overall survival (OS), and change in plasma 25(OH)D level.

RESULTS

Among 139 patients (mean age, 56 years; 60 [43%] women) who completed or discontinued chemotherapy and vitamin D3 (median follow-up, 22.9 months), the median PFS for high-dose vitamin D3 was 13.0 months (95% CI, 10.1 to 14.7; 49 PFS events) vs 11.0 months (95% CI, 9.5 to 14.0; 62 PFS events) for standard-dose vitamin D3 (log-rank P = .07); multivariable hazard ratio for PFS or death was 0.64 (1-sided 95% CI, 0 to 0.90; P = .02). There were no significant differences between high-dose and standard-dose vitamin D3 for tumor ORR (58% vs 63%, respectively; difference, -5% [95% CI, -20% to 100%], P = .27) or OS (median, 24.3 months vs 24.3 months; log-rank P = .43). The median 25(OH)D level at baseline for high-dose vitamin D3 was 16.1 ng/mL vs 18.7 ng/mL for standard-dose vitamin D3 (difference, -2.6 ng/mL [95% CI, -6.6 to 1.4], P = .30); at first restaging, 32.0 ng/mL vs 18.7 ng/mL (difference, 12.8 ng/mL [95% CI, 9.0 to 16.6], P < .001); at second restaging, 35.2 ng/mL vs 18.5 ng/mL (difference, 16.7 ng/mL [95% CI, 10.9 to 22.5], P < .001); and at treatment discontinuation, 34.8 ng/mL vs 18.7 ng/mL (difference, 16.2 ng/mL [95% CI, 9.9 to 22.4], P < .001). The most common grade 3 and higher adverse events for chemotherapy plus high-dose vs standard-dose vitamin D3 were neutropenia (n = 24 [35%] vs n = 21 [31%], respectively) and hypertension (n = 9 [13%] vs n = 11 [16%]).

CONCLUSIONS AND RELEVANCE

Among patients with metastatic CRC, addition of high-dose vitamin D3, vs standard-dose vitamin D3, to standard chemotherapy resulted in a difference in median PFS that was not statistically significant, but with a significantly improved supportive hazard ratio. These findings warrant further evaluation in a larger multicenter randomized clinical trial.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01516216.

A phase I/II study of RX-3117, an oral antimetabolite nucleoside, in combination with nab-paclitaxel (nab-pac) as first-line treatment of metastatic pancreatic cancer (met-PC): Preliminary results

420

Background: RX-3117 is an oral small molecule antimetabolite, cyclopentyl pyrimidyl nucleoside that is activated by cancer-enriched uridine cytidine kinase 2. Single agent RX-3117 has demonstrated efficacy in a phase III single agent clinical study of RX-3117 in met-PC and bladder cancer. RX-3117 in combination with nab-pac is being evaluated as first line treatment of met-PC cancer. Methods: This is a multicenter, open label phase I/II study (NCT03189914). Eligible subjects (aged ≥ 18 years) have histologically or radiologically proven met-PC with no prior therapies for metastatic disease, ECOG PS 0-1, and normal lab values. phase I identified the MTD dose that is being further evaluated in the phase II: RX-3117 (700 mg administered orally once-daily for 5 consecutive days with 2 days off per week) and nab-pac (125 mg/m2 administered once weekly) for 3 weeks with 1 week off per 4-week cycle. The Safety Committee reviewed data from phase I before moving to phase II. The primary endpoint of phase II (dose expansion) is an adequate number of responders based on PFS at 4 months and/or objective clinical response per RECIST v1.1. Results: As of September 21, 2018, 8 phase I subjects and 13 phase II subjects were enrolled and treated (9 males and 12 females, median age 67 years). The most common (≥ 15%) related adverse events were nausea, diarrhea, fatigue, alopecia, decreased appetite, rash, vomiting, and anemia. Fourteen subjects had at least one on-study scan (after 2 cycles). One subject experienced a complete response (CR) after 6 cycles of therapy with normalization of CA19.9 (-76%). Three subjects exhibited a partial response (PR): two after 2 cycles (39-47%) and one after 4 cycles of therapy (36%). Eight subjects had stable disease for at least 2 months, and 4 subjects had PFS of at least 4 months. The disease control rate (CR+PR+SD) was 86% in evaluable subjects while the overall response rate (CR+PR) was 29%. Conclusions: RX-3117 in combination with nab-pac appears to be safe and well tolerated in subjects with met-PC. Antitumor activity per RECIST was observed in 12 subjects. Phase II of the clinical study is currently ongoing. Clinical trial information: NCT03189914.

Halo 110-101: Early safety results of pegvorhyaluronidase alfa (PEGPH20; PVHA) + cisplatin (C) + gemcitabine (G) ± atezolizumab (ATZ) in patients (pts) with locally advanced or metastatic cholangiocarcinoma (CCA) and gallbladder cancer (GBC)

408

Background: Standard of care for CCA/GBC is C-G therapy. MAbs (ATZ, pembrolizumab) targeting PD-L1 show promise in treating CCA/GBC. Hyaluronan (HA), which may impede drug and immune cell access, is high (67%) in CCA/GBC tumors. PEGPH20 enzymatically degrades HA. HALO 110-101 (NCT03267940) evaluates safety and activity of PEG-C-G-ATZ or PEG-C-G versus C-G in CCA/GBC pts. Methods: This study comprises two parts. In Run-In (RI) six pts were enrolled in PEG-C-G arm, then six pts in PEG-C-G-ATZ arm. Eight additional pts may be enrolled for tolerability. In Expansion (EX), up to 50 pts will be enrolled for efficacy. Treatment (Tx) cycle is 21 days (d). PEGPH20 dose is 3 μg/kg on d1, eight and 15 and ATZ dose is 1200 mg (one–three hours after PEGPH20) on d1 (PEG-C-G-ATZ only). C-G is dosed at 25 mg/m2 C and 1000 mg/m2 G on d2 and nine. In C-G arm (EX only), C-G is dosed on d1 and 8. Primary endpoints are ORR (RECIST v1.1), AEs (NCI CTCAE v4.03), laboratory/safety (RI only); secondary endpoints are PK; DOR, DCR, PFS; OS, OS by PD-L1 expression; ORR and DOR (imRECIST). Results: Eighteen pts have been enrolled (nine in each arm). The mean (SD) age is 57 (12.2) yrs in PEG-C-G and 69 (8.8) yrs in PEG-C-G-ATZ. 56% were men. All pts experienced ≥ 1 AE. The most common AEs are nausea, fatigue (50% each); decreased appetite (44%); anemia, constipation (39% each); thrombocytopenia, oedema peripheral, AST increased, myalgia (33% each). To date, there has been one dose-limiting toxicity (febrile neutropenia) in the PEG-C-G arm. There have been no deaths due to AEs. Conclusions: The overall safety profile of PEGPH20 + C + G ± ATZ is acceptable and consistent with safety observed for the individual components. There were no DLTs resulting in a dose reduction of PEGPH20, which is being dosed at 3 μg/kg in the EX phase. Clinical trial information: NCT03267940. [Table: see text]

Germline cancer susceptibility gene variants, somatic second hits, and survival outcomes in patients with resected pancreatic cancer

PURPOSE

Germline variants in double-strand DNA damage repair (dsDDR) genes (e.g., BRCA1/2) predispose to pancreatic adenocarcinoma (PDAC) and may predict sensitivity to platinum-based chemotherapy and poly(ADP) ribose polymerase (PARP) inhibitors. We sought to determine the prevalence and significance of germline cancer susceptibility gene variants in PDAC with paired somatic and survival analyses.

METHODS

Using a customized next-generation sequencing panel, germline/somatic DNA was analyzed from 289 patients with resected PDAC ascertained without preselection for high-risk features (e.g., young age, personal/family history). All identified variants were assessed for pathogenicity. Outcomes were analyzed using multivariable-adjusted Cox proportional hazards regression.

RESULTS

We found that 28/289 (9.7%; 95% confidence interval [CI] 6.5-13.7%) patients carried pathogenic/likely pathogenic germline variants, including 21 (7.3%) dsDDR gene variants (3 BRCA1, 4 BRCA2, 14 other dsDDR genes [ATM, BRIP1, CHEK2, NBN, PALB2, RAD50, RAD51C]), 3 Lynch syndrome, and 4 other genes (APC p.I1307K, CDKN2A, TP53). Somatic sequencing and immunohistochemistry identified second hits in the tumor in 12/27 (44.4%) patients with germline variants (1 failed sequencing). Compared with noncarriers, patients with germline dsDDR gene variants had superior overall survival (hazard ratio [HR] 0.54; 95% CI 0.30-0.99; P = 0.05).

CONCLUSION

Nearly 10% of PDAC patients harbor germline variants, although the majority lack somatic second hits, the therapeutic significance of which warrants further study.

A Phase II and Biomarker Study of Sorafenib Combined with Modified FOLFOX in Patients with Advanced Hepatocellular Carcinoma

PURPOSE

Sorafenib is a standard first-line treatment for advanced hepatocellular carcinoma (HCC). The phase III SHARP trial showed a median time-to-progression (mTTP) of 5.5 months, overall response rate (ORR) of 2%, and median overall survival (mOS) of 10.7 months with sorafenib. FOLFOX4 has shown modest activity in advanced HCC. We evaluated the combination of sorafenib and modified (m)FOLFOX in a single-arm, multicenter phase II study.

PATIENTS AND METHODS

The study included Child-Pugh A patients with advanced HCC and no prior systemic therapies. Patients received sorafenib 400 mg twice a day for 2 weeks, followed by concurrent mFOLFOX [5-fluorouracil (5-FU) 1,200 mg/m²/day for 46 hours, leucovorin 200 mg/m², and oxaliplatin 85 mg/m² biweekly]. The primary endpoint was mTTP with an alternative hypothesis of 7 months, and secondary endpoints included ORR, mOS, and circulating biomarkers.

RESULTS

The study enrolled 40 patients: HCV/EtOH/HBV, 43%/28%/13%; Child-Pugh A5, 70%. Notable grade 3/4 adverse events (AE) included AST/ALT elevation (28%/15%), diarrhea (13%), hyperbilirubinemia (10%), hand-foot syndrome (8%), and bleeding (8%). mTTP was 7.7 months [95% confidence interval (CI): 4.4-8.9], ORR 18%, and mOS 15.1 months (7.9-16.9). Sorafenib + mFOLFOX increased plasma PlGF, VEGF-D, sVEGFR1, IL12p70, and CAIX and CD4⁺ and CD8⁺ effector T lymphocytes and decreased plasma sVEGFR2 and s-c-KIT and regulatory T cells (Tregs). Shorter TTP was associated with high baseline sVEGFR1. Shorter TTP and OS were associated with increases in Tregs and CD56^Dim natural killer (NK) cells after sorafenib alone and plasma sMET after combination treatment (all P < 0.05).

CONCLUSIONS

Sorafenib + mFOLFOX met the prespecified endpoint with encouraging efficacy but moderate hepatotoxicity. Thus, this regimen may be effective in select patients with adequate liver reserve. Biomarker evaluations suggested a correlation between time-to-progression (TTP) and angiogenic biomarkers and circulating Tregs.

Association of Alterations in Main Driver Genes With Outcomes of Patients With Resected Pancreatic Ductal Adenocarcinoma

Importance

Although patients with resected pancreatic adenocarcinoma are at high risk for disease recurrence, few biomarkers are available to inform patient outcomes.

Objective

To evaluate the alterations of the 4 main driver genes in pancreatic adenocarcinoma and patient outcomes after cancer resection.

Design, Setting, and Participants

This study analyzed protein expression and DNA alterations for the KRAS, CDKN2A, SMAD4, and TP53 genes by immunohistochemistry and next-generation sequencing in formalin-fixed, paraffin-embedded tumors in 356 patients with resected pancreatic adenocarcinoma who were treated at the Dana-Farber/Brigham and Women's Cancer Center (October 26, 2002, to May 21, 2012), University of Rochester Medical Center (March 1, 2006, to November 1, 2013), or Stanford Cancer Institute (September 26, 1995, to May 22, 2013). Associations of driver gene alterations with disease-free survival (DFS) and overall survival (OS) were evaluated using Cox proportional hazards regression with estimation of hazard ratios (HRs) and 95% CIs and adjustment for age, sex, tumor characteristics, institution, and perioperative treatment. Data were collected September 9, 2012, to June 28, 2016, and analyzed December 17, 2016, to March 14, 2017.

Main Outcomes and Measures

The DFS and OS among patients with resected pancreatic adenocarcinoma.

Results

Of the 356 patients studied, 191 (53.7%) were men and 165 (46.3%) were women, with a median (interquartile range [IQR]) age of 67 (59.0-73.5) years. Patients with KRAS mutant tumors had worse DFS (median [IQR], 12.3 [6.7 -27.2] months) and OS (20.3 [11.3-38.3] months) compared with patients with KRAS wild-type tumors (DFS, 16.2 [8.9-30.5] months; OS, 38.6 [16.6-63.1] months) and had 5-year OS of 13.0% vs 30.2%. Particularly poor outcomes were identified in patients with KRAS G12D-mutant tumors, who had a median (IQR) OS of 15.3 (9.8-32.7) months. Patients whose tumors lacked CDKN2A expression had worse DFS (median, 11.5 [IQR, 6.2-24.5] months) and OS (19.7 [10.9-37.1] months) compared with patients who had intact CDKN2A (DFS, 14.8 [8.2-30.5] months; OS, 24.6 [14.1-44.6] months). The molecular status of SMAD4 was not associated with DFS or OS, whereas TP53 status was associated only with shorter DFS (HR, 1.33; 95% CI, 1.02-1.75; P = .04). Patients had worse DFS and OS if they had a greater number of altered driver genes. Compared with patients with 0 to 2 altered genes, those with 4 altered genes had worse DFS (HR, 1.79 [95% CI, 1.24-2.59; P = .002]) and OS (HR, 1.38 [95% CI, 0.98-1.94; P = .06]). Five-year OS was 18.4% for patients with 0 to 2 gene alterations, 14.1% for those with 3 alterations, and 8.2% for those with 4 alterations.

Conclusions and Relevance

Patient outcomes are associated with alterations of the 4 main driver genes in resected pancreatic adenocarcinoma.

Neoadjuvant therapy outcomes in nonmetastatic pancreatic cancer

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Background: The optimal multidisciplinary treatment algorithm for pancreatic ductal adenocarcinoma (PDAC) is not well established. We studied outcomes in non-metastatic PDAC treated with chemotherapy and stereotactic body radiation therapy (SBRT) with or without pancreatic resection. Methods: Between August 2011 and July 2015, 73 patients with non-metastatic PDAC were treated with chemotherapy and SBRT with or without resection. Variables considered included: ECOG, CA 19-9, clinical stage, vascular involvement, pathologic stage and margin status. Resectability status was determined by an expert abdominal radiologist on initial staging imaging. Chemotherapy included FOLFIRINOX, FOLFOX, gemcitabine monotherapy (gem) or with nab-paclitaxel (gem/nab). SBRT was delivered as 30 Gy in 3 fractions over 5 days via CyberKnife. The Kaplan-Meier method and log-rank test were used to compare median overall survival (mOS), local progression free survival (LPFS) and metastasis free survival (MFS). Results: After a median follow-up of 19.3 months (mo) the mOS was 30.0 mo (95% CI, 19.4 to 36.5). The surgical group had longer mOS (36.5 vs 19.4 mo; P < 0.001), LPFS (29.0 vs 16.3 mo; P = 0.03) and MFS (29.0 vs 15.1 mo; P < 0.001) as compared to the nonsurgical group. FOLFIRINOX or gem/nab was associated with better mOS as compared to other chemotherapy (33.2 vs 12.8 mo; P < 0.001). There was a trend towards longer mOS in pts with initial imaging deemed less resectable (36.5 vs 30.1 vs 13.0 mo in unresectable vs borderline vs resectable; P = 0.19). In a multivariate analysis significant predictors of OS were resection, ECOG and FOLFIRINOX or gem/nab chemotherapy. Conclusions: Patients who had surgery after neoadjuvant chemotherapy and SBRT had significantly longer mOS, LPFS and MFS than those without surgery. FOLFIRINOX or gem/nab and better ECOG were also associated with improved outcomes. Worse resectablity status per imaging was associated with longer OS despite less likelihood of surgery; This may reflect more intensive neoadjuvant therapy or suggest that radiologic resectability status is a poor predictor of OS. Further investigation of factors underlying this discrepancy may have implications on neoadjuvant strategy and resectability determination.

A phase 2 and biomarker study of sorafenib combined with FOLFOX in patients with advanced hepatocellular carcinoma (HCC)

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Background: Sorafenib is the standard first line treatment for advanced HCC and showed a median time to progression (TTP) of 5.5 months and an overall response rate (ORR) of 2% in the phase III SHARP trial. FOLFOX has shown modest activity in HCC with a progression free survival (PFS) of 2.9 months and ORR of 8% in a phase III trial. In this single-arm, multicenter phase 2 and biomarker study, sorafenib plus FOLFOX was evaluated in the first line treatment of advanced HCC. Methods: Patients with histologically proven advanced HCC, Child Pugh A liver function, and no prior systemic therapies received sorafenib 400mg orally twice daily during a 2-week lead-in, followed by concurrent modified FOLFOX (5-FUCI 1200mg/m2/day for 46 hours and LV 400mg/m2 bolus, Oxaliplatin 85mg/m2) on day 1 and 15 of each 28-day cycle. The primary endpoint was TTP, calculated from date of study entry to date of radiological or clinical disease progression. Serial plasma anti-angiogenic and anti-inflammatory biomarkers were evaluated. Results: The study enrolled 40 patients with advanced HCC: median age, 65 years; male 85%; Child Pugh A5, 70%; BCLC stage C, 95%; HCC etiology, HCV 40%, HBV 13%, alcohol 13%. Grade 3/4 adverse events were notable for AST (23%), ALT (15%), bilirubin (10%), diarrhea (10%), anemia (10%), hypertension (5%), hand-foot syndrome (5%), and thrombocytopenia (5%). Dose reductions for sorafenib and FOLFOX were done in 73% and 65% of patients, respectively. The median TTP was 8.8 months (95%CI, 6.5-11.2). The ORR was 18%, and the stable disease rate was 55%. Among 36 patients with a baseline AFP ≥ 5 ng/mL, 10 (28%) had a ≥ 50% drop in AFP. Low baseline plasma levels of sVEGFR1, VEGF-C, and bFGF and high levels of s-cMET and IL-12 tended to associate with longer TTP (p < 0.10). Decreased s-cMET at day 15 and decreased s-cMET and IL-2 at day 43 were associated with longer TTP (p < 0.05). Conclusions: Sorafenib+FOLFOX demonstrated encouraging clinical efficacy with moderate toxicity in the first line treatment of advanced HCC. Initial biomarker evaluation suggested a correlation between TTP and baseline angiogenic markers as well as changes in IL-2 and s-cMET. Complete biomarker analysis will be presented at the meeting. Clinical trial information: NCT01775501.

HALO 110-101: A phase Ib, randomized, open-label study of PEGPH20 (pegvorhyaluronidase alfa) in combination with cisplatin (CIS) + gemcitabine (GEM) (PEGCISGEM) or atezolizumab and CIS + GEM (PEGCISGEMATEZO) in hyaluronan-high subjects with locally advanced or metastatic cholangiocarcinoma and gallbladder cancer

TPS543

Background: Cholangiocarcinoma (CCA) is treated with CIS and GEM (CISGEM), but prognosis is poor. Hyaluronan (HA) accumulation in solid tumors may impede drug and immune cell access. PEGPH20 targets tumors that accumulate HA (HA-high). This study (NCT03267940) plans to enroll 70 subjects to evaluate the safety and activity of PEGPH20 + programmed cell death-ligand 1 (PD-L1) agent atezolizumab, (PEGCISGEMATEZO), & PEGPH20 + CISGEM (PEGCISGEM) in HA-high subjects with CCA and gallbladder cancer. Study will comprise initial run-in and expansion portions. Primary endpoints include incidence of AEs and other laboratory/safety parameters and ORR (RECIST v1.1). Secondary endpoints include PK parameters; DOR, DCR, PFS, and ORR (RECIST v1.1 and immune-modified RECIST); and OS and OS by PD-L1 expression. Methods: ~6 HA-high subjects will be enrolled in PEGCISGEM arm run-in portion and undergo at ≥1 cycle; subsequently, 6 HA-high subjects will enter the PEGCISGEMATEZO arm. Treatment period will be 21-day cycles. In the expansion portion, ~50 HA-high subjects will be enrolled and randomized in a 2:2:1 ratio into PEGCISGEMATEZO, PEGCISGEM, and CISGEM arms. PEGPH20 is planned to be administered at 3.0 μg/kg on Days 1, 8 and 15 of all cycles in both portions. ATEZO will be administered at 1200 mg 1–3 hours after PEGPH20 on Day 1 of each 21-day cycle in the PEGCISGEMATEZO arm in both portions. In the PEGCISGEM & PEGCISGEMATEZO arms, dosing schedule for CISGEM is the same during both portions, with administration of 25 mg/m2 CIS and 1000 mg/m2 GEM on Days 2 and 9 of each cycle. In CISGEM control arm (expansion only), dosing schedule will be on Days 1 and 8 of each cycle. Treatment will continue until death, withdrawal of consent, disease progression, or unacceptable toxicity. Tumor response will be evaluated using RECIST v1.1. AEs will be graded per NCI CTCAE v4.03. Tumor samples will be tested retrospectively for PD-L1 expression. Safety data will be periodically monitored by an independent data monitoring committee. Clinical trial information: NCT03267940.

HALO 202: Randomized Phase II Study of PEGPH20 Plus Nab-Paclitaxel/Gemcitabine Versus Nab-Paclitaxel/Gemcitabine in Patients With Untreated, Metastatic Pancreatic Ductal Adenocarcinoma

Purpose Metastatic pancreatic ductal adenocarcinoma is characterized by excessive hyaluronan (HA) accumulation in the tumor microenvironment, elevating interstitial pressure and impairing perfusion. Preclinical studies demonstrated pegvorhyaluronidase alfa (PEGPH20) degrades HA, thereby increasing drug delivery. Patients and Methods Patients with previously untreated metastatic pancreatic ductal adenocarcinoma were randomly assigned to treatment with PEGPH20 plus nab-paclitaxel/gemcitabine (PAG) or nab-paclitaxel/gemcitabine (AG). Tumor HA levels were measured retrospectively using a novel affinity histochemistry assay. Primary end points were progression-free survival (PFS; overall) and thromboembolic (TE) event rate. Secondary end points included overall survival, PFS by HA level, and objective response rate. An early imbalance in TE events in the PAG arm led to a clinical hold; thereafter, patients with TE events were excluded and enoxaparin prophylaxis was initiated. Results A total of 279 patients were randomly assigned; 246 had HA data; 231 were evaluable for efficacy; 84 (34%) had HA-high tumors (ie, extracellular matrix HA staining ≥ 50% of tumor surface at any intensity). PFS was significantly improved with PAG treatment overall (hazard ratio [HR], 0.73; 95% CI, 0.53 to 1.00; P = .049) and for patients with HA-high tumors (HR, 0.51; 95% CI, 0.26 to 1.00; P = .048). In patients with HA-high tumors (PAG v AG), the objective response rate was 45% versus 31%, and median overall survival was 11.5 versus 8.5 months (HR, 0.96; 95% CI, 0.57 to 1.61). The most common treatment-related grade 3/4 adverse events with significant differences between arms (PAG v AG) included muscle spasms (13% v 1%), neutropenia (29% v 18%), and myalgia (5% v 0%). TE events were comparable after enoxaparin initiation (14% PAG v 10% AG). Conclusion This study met its primary end points of PFS and TE event rate. The largest improvement in PFS was observed in patients with HA-high tumors who received PAG. A similar TE event rate was observed between the treatment groups in stage 2 of the trial.

Lymph node metastases in resected pancreatic ductal adenocarcinoma: predictors of disease recurrence and survival

Background:

Few studies have simultaneously assessed the prognostic value of the multiple classification systems for lymph node (LN) metastases in resected pancreatic ductal adenocarcinoma (PDAC).

Methods:

In 600 patients with resected PDAC, we examined the association of LN parameters (AJCC 7th and 8th editions, LN ratio (LNR), and log odds of metastatic LN (LODDS)) with pattern of recurrence and patient survival using logistic regression and Cox proportional hazards regression, respectively. Regression models adjusted for age, sex, margin status, tumour grade, and perioperative therapy.

Results:

Lymph node metastases classified by AJCC 7th and 8th editions, LNR, and LODDS were associated with worse disease free-survival (DFS) and overall survival (OS) (all P_trend<0.01). American Joint Committee on Cancer 8th edition effectively predicted DFS and OS, while minimising model complexity. Lymph node metastases had weaker prognostic value in patients with positive margins and distal resections (both P_interaction<0.03). Lymph node metastases by AJCC 7th and 8th editions did not predict the likelihood of local disease as the first site of recurrence.

Conclusions:

American Joint Committee on Cancer 8th edition LN classification is an effective and practical tool to predict outcomes in patients with resected PDAC. However, the prognostic value of LN metastases is attenuated in patients with positive resection margins and distal pancreatectomies.

Abstract CT066: Global phase 3, randomized, double-blind, placebo-controlled study evaluating PEGylated recombinant human hyaluronidase PH20 (PEGPH20) plus nab-paclitaxel and gemcitabine in patients with previously untreated, hyaluronan (HA)-high, stage IV pancreatic ductal adenocarcinoma

Background: Poor outcome in pancreatic ductal adenocarcinoma (PDA) is associated partly with stromal hyaluronan (HA) accumulation, which may compromise chemotherapy access to tumors. In animal models, PEGPH20 degrades HA in tumors. Key endpoint data from a phase 2 study showed that PEGPH20 plus chemotherapy improved efficacy over chemotherapy alone in tumors retrospectively identified to accumulate HA (“HA-High”). The objectives of this phase 3 study are to compare efficacy and safety of standard-dose nab-paclitaxel (NAB) and gemcitabine (GEM) combined with either PEGPH20 or placebo in patients with HA-High, previously untreated, Stage IV PDA. Primary endpoints are progression-free survival (PFS) and overall survival (OS). Secondary endpoints are objective response rate, duration of response, and safety.

Methods: 420 patients ≥18 years with untreated HA-High metastatic PDA, ECOG PS 0-1 will be randomized (stratified by geographic region: North America/Europe/Other) 2:1 to NAB 125 mg/m2 + GEM 1000 mg/m2 + PEGPH20 3.0 μg/kg or to placebo. Patients with HA-High tumors will be prospectively identified by the co-developed VENTANA HA RxDx Assay, which indicates HA in the extracellular matrix. HA-High status (indicating patients who may achieve clinical benefit) was determined by Halozyme to be ≥50% staining based on clinical outcome data from a phase 2 study. Treatment will be provided in 4 week cycles (Wk 13, Wk 4 rest) until disease progression, unacceptable toxicity, death, or consent withdrawal. PEGPH20 or placebo will be given twice weekly (Cycle 1) then weekly (Cycles 2+), NAB + GEM once weekly for all cycles. Dexamethasone will be given before and after PEGPH20 administrations to reduce treatment related musculoskeletal symptoms and enoxaparin will be given to minimize thromboembolic events. Tumor response will be assessed by an independent central imaging vendor using RECIST v1.1. Adverse events will be graded per NCI CTCAE v4.03. An independent Data Monitoring Committee will evaluate safety and data for PFS and OS. Trial initiated Q12016 (EudraCT 2015-004068-13; NCT02715804).

Citation Format: Lei Zheng, Andrew E. Hendifar, Michele Reni, William P. Harris, Michel Ducreux, Andrea J. Bullock, Pippa G. Corrie, Tara Seery, Dimitrios Chondros, Eric Van Cutsem. Global phase 3, randomized, double-blind, placebo-controlled study evaluating PEGylated recombinant human hyaluronidase PH20 (PEGPH20) plus nab-paclitaxel and gemcitabine in patients with previously untreated, hyaluronan (HA)-high, stage IV pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT066. doi:10.1158/1538-7445.AM2017-CT066

Randomized phase II study of PEGPH20 plus nab-paclitaxel/gemcitabine (PAG) vs AG in patients (Pts) with untreated, metastatic pancreatic ductal adenocarcinoma (mPDA)

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Background: Hyaluronan (HA) accumulation in the tumor microenvironment produces elevated tumor pressure, vascular compression, and reduced drug delivery. PEGPH20 degrades HA, increasing the access and therapeutic index of anticancer agents. Methods: In Stage 1 of this phase II study, pts with untreated mPDA were randomized 1:1 to PAG (P; 3 µg/kg IV 2x/wk x 3 wks in C1, then 1x/wk x 3 wks in C2+, plus AG) vs AG every 28 days. An imbalance in thromboembolic (TE) events in the PAG arm led to a clinical hold (~40% of pts discontinued PEGPH20), exclusion of pts at high risk for TE events and enoxaparin prophylaxis in both study arms. In Stage 2, randomization was 2:1 to PAG vs AG. Tumor HA was tested using a novel assay (VENTANA HA RxDx). Primary endpoints were PFS (evaluable pts) and TE event rate (Stage 2). Secondary endpoints were PFS by HA level and ORR. Results: 279 pts were randomized; 231 are evaluable for efficacy. Of 246 pts with HA data, 84 (34%) were HA-High. As of December 16, 2016, the primary PFS endpoint was statistically significant for PAG vs AG (HR 0.73, 95% CI 0.53-1.00; p = 0.048) (Table). PFS in HA-High pts was also statistically significant in the PAG vs AG arm (HR 0.51; 95% CI 0.26-1.00; p = 0.048). ORR in HA-High pts was 46% (PAG) vs 34% (AG). Overall survival in HA-High pts (exploratory) was 11.5 months (mo) (PAG) and 8.5 mo (AG) (HR 0.96, 95% CI 0.57-1.61). TE events were similar (PAG 14% vs AG 10%) following enoxaparin initiation. All grade treatment-related AE included peripheral edema (PAG 63% vs AG 26%), muscle spasms (56% vs 3%), neutropenia (34% vs 19%), and myalgia (26% vs 7%). Conclusions: Randomized Phase II study met both primary endpoints (PFS and TE event rate), with the largest improvement in the secondary endpoint of PFS in HA-High pts. These data support HA as a potential predictive biomarker for patient selection of PEGPH20, currently investigated in the ongoing global Phase III HALO 301 study with PFS and OS as co-primary endpoints. Clinical trial information: NCT01839487. [Table: see text]

Understanding the non-curative potential of palliative chemotherapy: Do patients hear what they want to hear?

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Background: Misconceptions about the curative potential of PC are common, and may arise from gaps in informed consent. Another contributing factor could be patients’ desire, or lack of desire, for information about prognosis and PC outcomes. Methods: We surveyed 137 patients with advanced colorectal (N = 102) or pancreatic cancer (N = 35) within 2 weeks of consultation about 1st or 2ndline PC, as part of randomized trial of a PC education intervention at 6 US sites. Patients rated how much information they wanted about PC risks/benefits, including impact on prognosis. Responses ranged from no information to as much as possible on a 5-point Likert scale. They reported decision-making preferences; whether a doctor discussed curability, and how likely they thought PC was to cure their cancer. Chi square and Wilcoxon tests examined whether information and decision-making preferences, or curability discussions were associated with expectations of cure. Multivariable logistic regressions evaluated whether associations were modified by age, race, gender, marital status, or cancer type. Results: Only 44.5% of patients accurately reported that their cancer was not at all likely to be cured by PC. Most patients wanted a lot, or as much information as possible about PC risks/benefits, including likelihood of cure (81.7%), cancer control (84.7%), and impact on length of life (80.3%). Most patients preferred shared (70.8%) versus active or passive decision-making. Neither decision-making nor prognostic information preferences were associated with expectations of cure. Patients (13.9%) who did not recall curability discussions were less likely to have accurate expectations (21% v 48%; OR, 0.29; 95% CI, 0.07-.97). Patient characteristics did not significantly confound this association. Conclusions: Most patients value shared decision-making and want maximal information about PC risks/benefits, including impact on prognosis. Despite wanting prognostic information and reporting curability discussions, many patients report inaccurate expectations about cure from PC. Future studies should examine whether these assertions reflect misunderstandings, differences in belief, or expressions of hope.

Results of a randomized phase II trial of an anti-notch 2/3, tarextumab (OMP-59R5, TRXT, anti-Notch2/3), in combination with nab-paclitaxel and gemcitabine (Nab-P+Gem) in patients (pts) with untreated metastatic pancreatic cancer (mPC)

279

Background: Tarextumab (TRXT), fully human IgG2 antibody inhibits signaling of Notch2/ 3 receptors. Tumor regression seen in Notch3 (N3) expressing pt-derived pancreatic cancer xenografts when TRXT combined with Nab-P+Gem. Phase 2, randomized, placebo-controlled trial conducted to evaluate efficacy, safety of combination in mPC. Methods: Pts randomized 1:1 to TRXT or placebo (PL). TRXT given IV at 15 mg/kg q 2wks (D 1, 15), nab-P 125 mg/m2, GEM 1000mg/m2 on D1, 8, 15 q 28 days. Tissue for N3 gene expression determination was required. Primary endpoints: overall survival (OS) in all and in 3 subgroups determined by Notch 3 gene expression. Secondary: safety, progression-free survival (PFS) and overall response rate (ORR). Results: N = 177 pts randomized. Performance status (0 or 1), CA19-9 stratum (0 – ULN, > ULN – 59ULN, ≥ 59ULN) balanced. Clinical trial information: NCT01647828. .  Conclusions: Addition of TRXT to Nab-P+Gem did not improve OS in 1st line mPC. A potential detrimental effect on PFS and ORR was seen in subjects with N3 < 25%ile.[Table: see text]

Interim results of a randomized phase II study of PEGPH20 added to nab-paclitaxel/gemcitabine in patients with stage IV previously untreated pancreatic cancer

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Background: Poor outcome in pancreatic cancer (PDA) is associated partly with stromal hyaluronan (HA) accumulation, which compromises chemotherapy perfusion. PEGPH20, PEGylated recombinant human hyaluronidase, potentiates chemotherapy by depleting HA in tumors. Methods: In an ongoing, phase II, open-label, randomized study of PEGPH20+nab-paclitaxel (Nab)+Gemcitabine (Gem) (PAG) vs Nab+Gem (AG) in previously untreated stage IV PDA, pts receive PEGPH20 3 µg/kg twice weekly (C1), then weekly (C2+) with standard AG dosing. HA status was tested retrospectively. After a temporary clinical hold (Apr-Jul 2014) for an imbalance in thromboembolic (TE) events (29% PAG vs 15% AG), the protocol was amended to exclude high-TE-risk pts and add enoxaparin (LMWH) prophylaxis. Endpoints are PFS and TE events (primary); PFS and ORR by HA level and OS (secondary). Efficacy and safety data through Dec 2014 are for pts enrolled up to clinical hold (Stage 1); TE data are through Sep 2015 (Stage 2). Results: 135 pts were treated (74 PAG, 61 AG). PFS results are shown below (median follow-up 7 mo). In HA-high pts receiving PAG vs AG, ORR was 52% (1 CR) vs 24% (P=.038); ORR was 37% vs 38% in HA-low pts. OS was 12 mo vs 9 mo (HR=0.62) despite 12/23 PAG pts discontinuing PEGPH20 at clinical hold. Common ADRs (PAG vs AG) included peripheral edema (58% vs 31%), muscle spasms (55% vs 1.6%), and neutropenia (32% vs 18%). TE events were: Stage 1 42% vs 25% (no LMWH); Stage 2 (with LMWH; 40 mg/d or 40 mg/d increased to 1 mg/kg/d) 28% vs 29%; (1 mg/kg/d) 5% vs 6%; overall (40 mg/d or 1 mg/kg/d) 13% each arm (to be updated). Conclusions: Pts with HA-high tumors receiving PAG, vs AG, showed significant improvements in PFS and ORR and a trend toward improved OS. PAG was well tolerated, with TE events reduced with LMWH prophylaxis. A global phase III trial of PAG will initiate Q1 2016. Clinical Trial Information: NCT01839487. Clinical trial information: NCT01839487. [Table: see text]