Impact of Neoadjuvant Concurrent Chemoradiation (NACCRT) on Operability and Survival in Locally Advanced Inoperable Breast Cancer

PURPOSE/OBJECTIVE(S)

Inoperable locally advanced breast cancers (LABC) are treated with neoadjuvant chemotherapy (NACT). However, many patients remain inoperable after NACT due to an inadequate response. We, therefore, investigated the role of neoadjuvant concurrent chemoradiation (NACCRT) in this setting.

MATERIALS/METHODS

Patients with inoperable Stage III LABC were prospectively recruited in the study between May 2017 and December 2021. NACT consisted of 4 cycles of q3weekly Adriamycin (60 mg/m2) and Cyclophosphamide (600mg/m2), and 4 cycles of q3weekly Paclitaxel (175 mg/m2). Concurrent radiotherapy with 6 MV X-rays was given using a 3D conformal technique to a total dose of 46 Gy (2 Gy/fraction, 5 days/week) to the involved breast, axilla, supraclavicular fossa, and internal mammary chain (upper 3 intercostal spaces) along with the first two cycles of paclitaxel. A 0.5 cm bolus was used to boost the skin till the appearance of hyperpigmentation. All patients were assessed for surgery after the completion of the planned neoadjuvant treatment. Adjuvant treatments were given based on the receptor status. The impact of neoadjuvant CTRT on the pathological complete response (pCR), operability, and survival was analyzed. Event-free survival (EFS) and Overall Survival (OS) were analyzed using the Kaplan-Meier method.

RESULTS

The study enrolled 202 female patients with a median age of 52 years, with 23.7% having IIIA, 65.3% IIIB, and 10.8% having IIIC disease. Hormone-receptor (HR) positive disease was observed in 90/202 (44.6%) patients, triple-negative (TNBC) in 50/202 (24.8%) and Her2/neu positive in 62/202 (30.7%) patients. Modified radical mastectomy was performed in 88.1% of patients, with 8.5% remaining inoperable and 3.4% declining surgery due to clinical complete response (cCR). Among the patients who underwent MRM, 65/178 (32.2%) patients had a pCR. pCR was observed in 13/81 (16%) with HR-positive disease, 21/46 (45.6%) with TNBC, and 31/51 (60.7%) patients with Her2/neu-positive disease. Grade 3 skin reactions were observed in 39/202 (19.3%). Postoperative wound morbidity requiring hospitalization was observed in 19/178 (10.6%) patients. The median follow-up was 42 months, with 4-year EFS and OS of 63.8% and 71.5%, respectively. Six out of 7 patients who were in cCR and declined surgery are alive and remain in cCR. On subgroup analysis of Her 2 positive patients, pCR was significantly associated with improved EFS and OS (89.8% vs 33.3%, p = 0.001 and 89.1% vs 44.4%, p = 0.001 respectively).

CONCLUSION

Our study demonstrates the feasibility and efficacy of NACCRT in improving operability, pCR rates and survival outcomes in patients with inoperable LABC. The results suggest that NACCRT can be considered for use in clinical practice with careful patient selection. These findings contribute to the ongoing efforts to optimize treatment for this patient population and warrant further investigation in larger, randomized trials.

Phase II study (daNIS-1) of the anti–TGF-β monoclonal antibody (mAb) NIS793 with and without the PD-1 inhibitor spartalizumab in combination with nab-paclitaxel/gemcitabine (NG) versus NG alone in patients (pts) with first-line metastatic pancreatic ductal adenocarcinoma (mPDAC)

TPS761

Background: Overall survival remains short for pts with mPDAC despite approved therapies, highlighting the need for more effective treatment options. While TGF-β can act as a tumor suppressor in normal tissue and early-stage PDAC, it is associated with tumorigenic processes (such as enhanced genomic instability, neoangiogenesis, epithelial-to-mesenchymal transition, and metastasis) observed in late-stage PDAC. Within the pancreatic tumor microenvironment (TME), TGF-β activates stellate cells and cancer-associated fibroblasts, thereby promoting fibrotic network development and immune exclusion, maintaining an immunosuppressive TME. Preclinical data in murine models have shown that addition of TGF-β blockade to anti-PD-1 therapy or NG augmented the antitumor activity of those agents, leading to tumor regression. These data provide the rationale for combining TGF-β-targeting agents with chemotherapy and/or immunotherapy. This study investigates NIS793, a human IgG2 mAb that binds TGF-β1 and 2, with and without spartalizumab (PD-1 antagonist) combined with NG in treatment-naïve mPDAC. Methods: This is a phase II open-label, randomized study (NCT04390763) with a safety run-in period followed by randomization. Eligible pts are adults with previously untreated mPDAC with measurable disease as per RECIST 1.1 and ECOG performance status score ≤1. Pts are excluded if they have a microsatellite-unstable tumor. The safety run-in was completed and confirmed a dose of NIS793 (intravenously [IV] 2100 mg Q2W) + spartalizumab (IV 400 mg Q4W) + nab-paclitaxel (IV 125 mg/m2 on Days 1, 8, and 15) + gemcitabine (IV 1000 mg/m2 on Days 1, 8, and 15). In the randomized part, pts will be randomized 1:1:1 to NIS793 + spartalizumab + NG (n = 50) or NIS793 + NG (n = 50) or NG (n = 50). Treatment will continue until disease progression, unacceptable toxicity, discontinuation by investigator’s/pt’s choice, or withdrawal of consent. The primary objective is to evaluate the progression-free survival per RECIST v1.1 of NIS793 + NG with or without spartalizumab, versus NG alone. Secondary objectives include safety and tolerability, antitumor activity, overall survival, change in tumoral CD8 and PD-L1 status, and characterization of immunogenicity and pharmacokinetics. Efficacy will be assessed by investigator per RECIST v1.1 and iRECIST at screening, every 8 weeks for 1 year and then every 12 weeks until disease progression. The study is ongoing and has an estimated enrollment of 161 pts. There are currently 31 sites participating across 14 countries. The study is funded by Novartis. Clinical trial information: NCT04390763 .

Quantitation of the ataxia-telangiectasia-mutated and Rad3-related inhibitor elimusertib (BAY-1895344) in human plasma using LC-MS/MS

Ataxia-telangiectasia-mutated and Rad3-related (ATR) is master regulator of the DNA-damage response that, through multiple mechanisms, can promote cancer cell survival in response to replication stress from sources, including chemotherapy and radiation. Elimusertib (BAY-1895344) is an orally available small-molecule ATR inhibitor currently in preclinical and clinical development for cancer treatment. To support these studies and define elimusertib pharmacokinetics, we developed a HPLC-MS method for its quantitation. A 50-μL volume of plasma was subjected to acetonitrile protein precipitation and then chromatographic separation using a Phenomenex Polar-RP column (2 × 50 mm, 4 μm) and a gradient mobile phase consisting of 0.1% formic acid in acetonitrile and water during a 7-min run time. Mass spectrometric detection was achieved using a SCIEX 4000 triple-stage mass spectrometer with electrospray positive-mode ionization. With a stable isotopic internal standard, the assay was linear from 30 to 5000 ng/mL and proved to be both accurate (93.5-108.2%) and precise (<6.3% coefficient of variation) fulfilling criteria from the Food and Drug Administration guidance on bioanalytical method validation. This LC-MS/MS assay will support several ongoing clinical studies by defining elimusertib pharmacokinetics.

Phase II study (daNIS-1) of the anti-TGF-β monoclonal antibody (mAb) NIS793 with and without the PD-1 inhibitor spartalizumab in combination with nab-paclitaxel/gemcitabine (NG) versus NG alone in patients (pts) with first-line metastatic pancreatic ductal adenocarcinoma (mPDAC)

TPS4183

Background: Overall survival remains low for pts with mPDAC despite approved therapies, highlighting the need for further innovative treatment options. Intra-tumoral fibrosis that characterizes PDAC has been associated with a state of immune exclusion and may constitute a mechanical obstacle to the intra-tumoral penetration of chemotherapy as well as contribute to the lack of efficacy of immunotherapy. TGF-β plays a key role in regulating the tumor microenvironment and emerging evidence points to its role as a pivotal activator of cancer-associated fibroblasts, leading to the development of fibrotic networks. Preclinical data in murine models have shown that TGF-β blockade augmented the antitumor activity of both NG and anti-PD-1 therapy, leading to tumor regression. These data provide the rationale for combining TGF-β-targeting agents with immunotherapy and chemotherapy. NIS793 is a human IgG2 mAb that binds to TGF-β. This study investigates NIS793 with and without spartalizumab (PD-1 antagonist) combined with NG in treatment naïve mPDAC. Methods: This is a phase II open-label, randomized, multicenter study (NCT04390763) beginning with a safety run-in period followed by randomization. Eligible pts are adults with previously untreated mPDAC and ECOG performance status score ≤1. Pts are excluded if they have a microsatellite-unstable tumor. The safety run-in data will be analyzed after ≥6 pts have received NIS793 (intravenously [IV] 2100 mg Q2W) + spartalizumab (IV 400 mg Q4W) + nab-paclitaxel (IV 125 mg/m2 on Days 1, 8 and 15) + gemcitabine (IV 1000 mg/m2 on Days 1, 8 and 15) for 1 cycle (28 days) to assess the safety and tolerability of the combination. In the randomized part, pts will be randomized 1:1:1 to NIS793 + spartalizumab + NG (n = 50) or NIS793 + NG (n = 50) or NG (n = 50). Treatment will continue until unacceptable toxicity, disease progression, discontinuation by investigator’s/pt’s choice, or withdrawal of consent. The primary objective is to evaluate the progression-free survival per RECIST 1.1, of NIS793 + NG ± spartalizumab versus NG alone. Secondary objectives include safety and tolerability, antitumor activity, overall survival, change in tumoral CD8 and PD-L1 status, and characterization of immunogenicity and pharmacokinetics. Efficacy will be assessed locally per RECIST v1.1 and iRECIST at screening, every 8 weeks for 1 year and then every 12 weeks until disease progression. Blood and tumor samples will be taken at baseline and during study treatment for pharmacokinetic, immunogenicity and biomarker assessments. This study is ongoing and will enroll pts from 31 sites across 14 countries. The first pt was treated on October 22, 2020. Enrollment for the randomized part of the study started on August 09, 2021. Clinical trial information: NCT04390763.

NSABP FC-12: A single-arm, phase II study to evaluate treatment with gevokizumab in patients with stage II/III colon cancer who remain ctDNA+ after curative surgery and adjuvant chemotherapy

TPS3642

Background: Detection of circulating tumor DNA (ctDNA) in patients (pts) following surgery is indicative of presence of minimal/molecular residual disease (MRD) and confers a near-certain risk of disease recurrence. Therapeutic strategies to treat MRD following standard curative therapies are needed because the risk of recurrence is high and therapeutic intervention may provide clinical benefit to patients. Gevokizumab is a recombinant humanized monoclonal antibody targeting interleukin-1β (IL-1β), which is involved in all phases of the malignant process (tumorigenesis, invasion, metastasis, angiogenesis, progression, and the modulation of anti-tumor immunity). Gevokizumab has been validated in pre-clinical colon cancer (CC) models and safety established in the advanced-stage clinical setting. In this trial in progress, we aim to test the efficacy of gevokizumab in pts with early-stage CC with MRD (ctDNA-positivity) following definitive treatment. Methods: NSABP FC-12 is a single-arm, multi-centered phase II study that will include pts with stage II/III CC who test MRD+ within 6 wks following completion of curative surgery and ≥3 mos of adjuvant chemotherapy. MRD will be assessed using a personalized and tumor-informed ctDNA assay (Signatera bespoke assay). Gevokizumab will be given at a flat dose of 120 mg IV every 28 days for 13 cycles. The primary endpoint is relapse-free survival (RFS) following initiation of study therapy through one year of follow-up. Secondary endpoints are rate of ctDNA clearance at 8 wks from start of study therapy, as well as safety, toxicity, pharmacokinetics, and immunogenicity of gevokizumab. Exploratory and correlative endpoints will include outcomes associated with ctDNA clearance kinetics, tumor mutations, tumor mutational burden, circulating methylated DNA, tumor immune microenvironment profile, peripheral blood immune profile, and stool microbiome analyses. The enrollment period will be ̃12 mos. Pts will be followed for 18 mos following enrollment with ctDNA analysis at prespecified timepoints until imaging is positive for recurrence of disease or death. CT scans will be at 6-mo intervals. RFS will be determined in pts who clear ctDNA at 8 wks compared to those who do not. A single-stage design to test the null hypothesis that the 12-mo RFS is P≥0.20 versus the alternative (HA) that P≥0.35 has a sample size of 31 (alpha=0.151; power 0.811). If ≥9 of 31 pts (29%) are alive and recurrence-free at 12 mos, then gevokizumab will be considered promising for further study. Enrollment continues towards the primary endpoint. Clinical trial information: 05178576.

Nivolumab (NIVO) ± ipilimumab (IPI) in patients (pts) with microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) metastatic colorectal cancer (mCRC): Five-year follow-up from CheckMate 142

3510

Background: NIVO ± IPI is approved in previously treated pts with MSI-H/dMMR mCRC in the US, EU, and Japan, based on findings from the phase 2 CheckMate 142 study (NCT02060188). NCCN guidelines include NIVO + IPI as an initial therapy option for pts with MSI-H/dMMR mCRC. Results from a ~5-year follow-up from CheckMate 142 cohorts 1–3 (C1–3) are reported here. Methods: In this non-randomized, multicohort study, pts with MSI-H/dMMR mCRC were treated as follows: C1 (2L+; NIVO 3 mg/kg Q2W), C2 (2L+; NIVO 3 mg/kg + IPI 1 mg/kg Q3W [4 doses], followed by NIVO 3 mg/kg Q2W) and C3 (1L; NIVO 3 mg/kg Q2W + IPI 1 mg/kg Q6W), until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) by investigator assessment (INV) per RECIST v1.1. Other key endpoints were disease control rate (DCR), duration of response (DOR), progression-free survival (PFS), all by INV and blinded independent central review; overall survival (OS), and safety. Results: In C1 (N = 74), C2 (N = 119), and C3 (N = 45), median (range) follow-up (time from first dose to data cutoff) was 70.0 (66.2–88.7), 64.0 (60.0–75.8), and 52.4 (47.6–57.1) months (mo), respectively. ORR (95% CI) by INV was 39% (28–51), 65% (55–73), and 71% (56–84; Table) and progressive disease (PD) rates were 26%, 12%, and 16% in C1, C2, and C3, respectively. Median DOR was not reached in the 3 cohorts. The 48-mo PFS rates were 36%, 54%, and 51% and 48-mo OS rates were 49%, 71%, and 72% in C1, C2, and C3, respectively (Table). PFS and OS rates with up to 60 mo of follow-up will be presented. Safety data are shown in the table. Conclusions: With extended follow-up of ~5 years, NIVO ± IPI continued to demonstrate durable OS and PFS benefit, with no new safety signals. These updated data further support current treatment recommendations for 2L+ NIVO ± IPI and 1L NIVO + IPI for pts with MSI-H/dMMR mCRC. Clinical trial information: NCT02060188. [Table: see text]

Efficacy and safety of larotrectinib in patients with TRK fusion-positive thyroid carcinoma

OBJECTIVE

Larotrectinib is a highly selective tropomyosin receptor kinase (TRK) inhibitor with demonstrated efficacy across various TRK fusion-positive solid tumours. We assessed the efficacy and safety of larotrectinib in patients with TRK fusion-positive thyroid carcinoma (TC).

METHODS

We pooled data from three phase I/II larotrectinib clinical trials (NCT02576431, NCT02122913, and NCT02637687). The primary endpoint was the investigator-assessed objective response rate (ORR) per Response Evaluation Criteria in Solid Tumors v1.1. Secondary endpoints included duration of response (DoR), progression-free survival (PFS), overall survival (OS), and safety. Data cut-off: July 2020.

RESULTS

Twenty-nine patients (median age: 60; range: 6-80) with TRK fusion-positive TC were treated. Tumour histology was papillary (PTC) in 20 (69%) patients, follicular (FTC) in 2 (7%), and anaplastic (ATC) in 7 (24%) patients. Among 28 evaluable patients, ORR was 71% (95% CI: 51-87); best responses were complete response in 2 (7%) patients, partial response in 18 (64%), stable disease in 4 (14%), progressive disease in 3 (11%), and undetermined in 1 (4%) due to clinical progression prior to the first post-baseline assessment. ORR was 86% (95% CI: 64-97) for PTC/FTC and 29% (95% CI 4-71) for ATC. Median time to response was 1.87 months (range 1.64-3.68). The 24-month DoR, PFS, and OS rates were 81, 69, and 76%, respectively. Treatment-related adverse events were mainly grades 1-2.

CONCLUSION

In TRK fusion-positive TC, larotrectinib demonstrates rapid and durable disease control and a favourable safety profile in patients with advanced disease requiring systemic therapy.

SIGNIFICANCE STATEMENT

NTRK gene fusions are known oncogenic drivers and have been identified in various histologies of thyroid carcinoma, most commonly in papillary thyroid carcinoma. This is the first publication specifically studying a TRK inhibitor in a cohort of TRK fusion-positive thyroid carcinoma patients. In the current study, the highly selective TRK inhibitor larotrectinib showed durable antitumour efficacy and a favourable safety profile in patients with TRK fusion-positive thyroid carcinoma. Our findings show that patients with advanced non-medullary thyroid carcinoma who may require systemic therapy could be considered for testing for gene fusions by next-generation sequencing.

Phase II study of durvalumab following neoadjuvant chemoRT in operable rectal cancer: NSABP FR-2

99

Background: Although immunotherapy shows no benefit in microsatellite stable (MSS) colorectal cancer, preclinical models suggest that radiotherapy (RT) can enhance neoantigen presentation, modulate the microenvironment, and improve the likelihood of anti-tumor activity with checkpoint inhibitor use. Using a “window-of-opportunity” study design, this prospective phase II trial will determine the safety and activity of this approach with the anti-PD-L1 agent durvalumab (MEDI4736). Methods: Stage II/III patients (pts) with MSS rectal cancer undergoing standard NCCN guideline-compliant neoadjuvant chemoradiotherapy (CRT) followed by definitive surgery were eligible. Treatment included durvalumab (750mg IV infusion once every 2 wks) for 4 total doses beginning within 3-7 days after CRT completion followed by surgery within 8-12 wks of the final CRT dose. Primary end point (EP): Improvement in modified neoadjuvant rectal cancer (mNAR) score (goal 10.6) compared to historical controls (15.6) targeting a 20% DFS RR reduction and 3-4% absolute OS improvement. Secondary EPs: toxicity, pCR, cCR, therapy completion, negative surgical margins, sphincter preservation, and exploratory assessments of tumor-infiltrating lymphocytes, tumor Immunoscore, circulating immunologic profiles, and molecular predictors of response. We test H0: mNAR ≥15.6 vs HA: mNAR <15.6 at alpha 0.10 one-sided with statistical significance defined as p<0.1. Results: From May 2018 to October 2020, 45 pts were enrolled with 40 pts evaluable for mNAR. Mean mNAR was 12.03 (80% CI: 9.29-14.97) (p=0.06 one-sided). pCR=22.2%; cCR=31.1%; R0 resection=81.0%, and sphincter preservation=71.4%. Side effects were consistent with both CRT and durvalumab safety profile. Most common grade 3 AEs included diarrhea, lymphopenia, and back pain. There was one grade 4 AE (elevated amylase/lipase) and no grade 5 AEs. Remaining secondary and correlative immunologic end points are still being assessed. Conclusions: Durvalumab immediately following CRT prior to surgery for definitive management of rectal cancer was safe and without unexpected short-term toxicities. The primary end point of mean mNAR score was significantly less than our historical control, warranting further investigation. Correlative analyses for immunologic markers of response including PD-(L)1 expression and Immunoscore are ongoing. NCT 03102047. Support: AstraZeneca-Medimmune, NSABP Foundation. Clinical trial information: NCT03102047.

Pembrolizumab plus azacitidine in patients with chemotherapy refractory metastatic colorectal cancer: a single-arm phase 2 trial and correlative biomarker analysis

Background

DNA mismatch repair proficient (pMMR) metastatic colorectal cancer (mCRC) is not responsive to pembrolizumab monotherapy. DNA methyltransferase inhibitors can promote antitumor immune responses. This clinical trial investigated whether concurrent treatment with azacitidine enhances the antitumor activity of pembrolizumab in mCRC.

Methods

We conducted a phase 2 single-arm trial evaluating activity and tolerability of pembrolizumab plus azacitidine in patients with chemotherapy-refractory mCRC (NCT02260440). Patients received pembrolizumab 200 mg IV on day 1 and azacitidine 100 mg SQ on days 1–5, every 3 weeks. A low fixed dose of azacitidine was chosen in order to reduce the possibility of a direct cytotoxic effect of the drug, since the main focus of this study was to investigate its potential immunomodulatory effect. The primary endpoint of this study was overall response rate (ORR) using RECIST v1.1., and secondary endpoints were progression-free survival (PFS) and overall survival (OS). Tumor tissue was collected pre- and on-treatment for correlative studies.

Results

Thirty chemotherapy-refractory patients received a median of three cycles of therapy. One patient achieved partial response (PR), and one patient had stable disease (SD) as best confirmed response. The ORR was 3%, median PFS was 1.9 months, and median OS was 6.3 months. The combination regimen was well-tolerated, and 96% of treatment-related adverse events (TRAEs) were grade 1/2. This trial was terminated prior to the accrual target of 40 patients due to lack of clinical efficacy. DNA methylation on-treatment as compared to pre-treatment decreased genome wide in 10 of 15 patients with paired biopsies and was significantly lower in gene promoter regions after treatment. These promoter demethylated genes represented a higher proportion of upregulated genes, including several immune gene sets, endogenous retroviral elements, and cancer-testis antigens. CD8⁺ TIL density trended higher on-treatment compared to pre-treatment. Higher CD8⁺ TIL density at baseline was associated with greater likelihood of benefit from treatment. On-treatment tumor demethylation correlated with the increases in tumor CD8⁺ TIL density.

Conclusions

The combination of pembrolizumab and azacitidine is safe and tolerable with modest clinical activity in the treatment for chemotherapy-refractory mCRC. Correlative studies suggest that tumor DNA demethylation and immunomodulation occurs. An association between tumor DNA demethylation and tumor-immune modulation suggests immune modulation and may result from treatment with azacitidine.

Trial registration ClinicalTrials.gov, NCT02260440. Registered 9 October 2014, https://clinicaltrials.gov/ct2/show/NCT02260440.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-021-01226-y.

POS0400 METABOLIC CHANGES INDUCED BY ANTI-MALONDIALDEHYDE/MALINDIALDEHYDE-ACETALDEHYDE ANTIBODIES PROMOTE OSTEOCLAST DEVELOPMENT

Background:

Malondialdehyde (MDA) is a highly reactive compound generated during lipid-peroxidation in conditions associated with oxidative stress. MDA can irreversibly modify proteins (e.g. lysine, arginine and histidine residues). In addition, acetaldehyde can further react with MDA adducts to form malondialdehyde-acetaldehyde (MAA) modification. Such protein modifications can lead to immunogenic neo-epitopes that are recognized by autoantibodies. In fact, anti-MDA/MAA IgG antibodies are significantly increased in the serum of patients with autoimmune diseases, such as rheumatoid arthritis (RA) (1). Interestingly, anti-MDA/MAA antibodies have been shown to promote osteoclast (OC) differentiation in vitro suggesting a potential role for these autoantibodies in bone damage associated with RA (1).

Objectives:

Little is known about the molecular mechanisms activated by autoantibodies in RA. Here, we elucidate the pathways specifically triggered by anti-MDA/MAA autoantibodies in developing osteoclasts.

Methods:

Recombinant human monoclonal anti-MDA/MAA antibodies, which were previously cloned from single synovial B cells of RA patients, were added to different OC assays. OCs were generated from monocyte-derived macrophages in the presence of the cytokines RANK-L and M-CSF. OC development was monitored by light microscopy following tartrate-resistant acid phosphatase staining and by erosion assays using calcium phosphate-coated plates. Bone morphometrics were studied in anti-MDA/MAA-injected mice using X-ray microscopy. Cellular metabolism was analyzed by mass spectrometry, Seahorse XF Analyzer and a colorimetric L-Lactate assay.

Results:

Anti-MDA/MAA antibodies induced a robust OC differentiation in vitro and bone loss in vivo. The anti-MDA/MAA antibodies acted on developing OCs by increasing glycolysis via an Fcγ receptor I-mediated pathway and the upregulation of the transcription factors HIF-1α, Myc and CHREBP. Such regulation of cellular metabolism was exclusively observed in the presence of the osteoclastogenic anti-MDA/MAA clones, whereas other RA-associated autoantibodies (anti-MDA/MAA or anti-citrullinated protein antibodies) had no effect on metabolism. The anti-MDA/MAA treatment induced a shift in the tricarboxylic acid (TCA) cycle activity in developing OCs, leading to the accumulation of citrate and aconitate.

Conclusion:

We described a novel type of autoantibody-induced pathway in RA, which might contribute to increased OC activation and a consequent bone loss. Anti-MDA/MAA antibodies promoted osteoclast development by increasing glycolysis and by modulating the TCA cycle through a signaling pathway that included Fcγ receptor I and a network of transcription factors acting on glycolysis. A TCA cycle bias towards citrate production suggests that the anti-MDA/MAA antibodies might stimulate OCs via increasing lipid biosynthesis in the cells.

References:

[1]Grönwall C. et al. J. Autoimmunity 84 (2017): 29-45.

Acknowledgements:

This Project has received funding from FOREUM, Foundation for Research in Rheumatology, from the European Research Council (ERC) grant agreement CoG 2017 - 7722209_PREVENT RA, the EU/EFPIA Innovative Medicine Initiative grant agreement 777357_RTCure, the Konung Gustaf V:s och Drottning Victorias Frimurarestiftelse and Knut and Alice Wallenberg Foundation.

Disclosure of Interests:

Koji Sakuraba: None declared, Akilan Krishnamurthy: None declared, Alexandra Circiumaru: None declared, Vijay Joshua: None declared, Heidi Wähämaa: None declared, Marianne Engström: None declared, Meng Sun: None declared, Xiaowei Zheng: None declared, Cheng Xu: None declared, Khaled Amara: None declared, Vivianne Malmström Grant/research support from: collaboration with Pfizer, unrelated to the abstract, Sergiu-Bogdan Catrina: None declared, Caroline Grönwall: None declared, Bence Réthi: None declared, Anca Catrina Grant/research support from: collaboration with BMS and Pfizer, unrelated to the present abstract

A Pancreatic Cancer Multidisciplinary Clinic Eliminates Socioeconomic Disparities in Treatment and Improves Survival

AIMS

National studies have demonstrated disparities in the treatment and survival of pancreatic cancer patients based on socioeconomic status (SES). This study aimed to identify specific differences in perioperative management and outcomes based on patient SES and to study the role of a multidisciplinary clinic (MDC) in mitigating any variations.

METHODS

The study analyzed patients undergoing pancreaticoduodenectomy for pancreatic ductal adenocarcinoma in a large hospital system. The patients were categorized into groups of high and low SES and whether they were managed by the authors' pancreatic cancer MDC or not. The study compared differences in disease characteristics, receipt of multimodality therapy, perioperative outcomes, and recurrence-free and overall survival.

RESULTS

Of the 162 low-SES patients and 119 high-SES patients, 54% were managed in the MDC. Outside the MDC, low-SES patients were less likely to receive neoadjuvant chemotherapy and had less minimally invasive surgery, a longer OR time, less enhanced recovery participation, and more major complications (p < 0.05). No SES disparities were observed among the MDC patients. Despite similar tumor characteristics, the low-SES patients had inferior median overall survival (21 vs 32 months; p = 0.005), but the MDC appeared to eliminate this disparity. Low SES correlated with inferior survival for the non-MDC patients (17 vs 32 months; p < 0.001), but not for the MDC patients (24 vs 25 months; p = 0.33). These findings persisted in the multivariable analysis.

CONCLUSION

A pancreatic cancer MDC standardizes treatment decisions, eliminates disparities in surgical outcomes, and improves survival for low-SES patients.

Gutting it Out: Developing Effective Immunotherapies for Patients With Colorectal Cancer

Risk factors for colorectal cancer (CRC) include proinflammatory diets, sedentary habits, and obesity, in addition to genetic syndromes that predispose individuals to this disease. Current treatment relies on surgical excision and cytotoxic chemotherapies. There has been a renewed interest in immunotherapy as a treatment option for CRC given the success in melanoma and microsatellite instable (MSI) CRC. Immunotherapy with checkpoint inhibitors only plays a role in the 4%-6% of patients with MSIhigh tumors and even within this subpopulation, response rates can vary from 30% to 50%. Most patients with CRC do not respond to this modality of treatment, even though colorectal tumors are frequently infiltrated with T cells. Tumor cells limit apoptosis and survive following intensive chemotherapy leading to drug resistance and induction of autophagy. Pharmacological or molecular inhibition of autophagy improves the efficacy of cytotoxic chemotherapy in murine models. The microbiome clearly plays an etiologic role, in some or most colon tumors, realized by elegant findings in murine models and now investigated in human clinical trials. Recent results have suggested that cancer vaccines may be beneficial, perhaps best as preventive strategies. The search for therapies that can be combined with current approaches to increase their efficacy, and new knowledge of the biology of CRC are pivotal to improve the care of patients suffering from this disease. Here, we review the basic immunobiology of CRC, current "state-of-the-art" immunotherapies and define those areas with greatest therapeutic promise for the future.

OP0326 ACPA-INDUCED PAIN-BEHAVIOR, BONE LOSS AND TENDON INFLAMMATION IN MICE: A NOVEL MODEL FOR THE PRE-DISEASE PHASES OF ACPA-POSITIVE RHEUMATOID ARTHRITIS

Background:

In rheumatoid arthritis (RA), anti-citrullinated protein antibodies (ACPAs) are associated with bone loss and pain. Recently, tenosynovitis has been suggested as a predicting factor for arthritis progression in individuals at-risk for RA.

Objectives:

We aimed to investigate if transfer of human ACPAs into mice could induce tenosynovitis and/or subclinical inflammation.

Methods:

Monoclonal ACPA (1325:04C03 and 1325:01B09) and control (1362:01E02) antibodies (mAbs) were generated from synovial plasma or memory B cells of RA patients. 2mg of combination of monoclonal ACPAs or control antibody were injected in BALB/c female mice (age 12-16 weeks) (n= 9). Pain-like behavior was monitored by measuring mechanical hypersensitivity using von Frey filaments every 3 days and estimation by up-down Dixon method. Bone morphometrics was analyzed by micro-CT. Using specially designed mobilization casts, dedicated mouse MRI coils, and gadolinium enhanced contrast medium, the hind limbs of these mice were scanned in a 9.4 T scanner and resulting T1-weighted images were evaluated for signs of soft tissue joint inflammation. The MRI images were scored for the presence of joint involvement and tendon inflammatory changes by 3 readers in a blinded manner.

Figure 1.

NAPA performed on healthy donor mo-DCs incubated with native, PAD2-citrullinated, and PAD4-citrullinated fibrinogen. Alpha, beta, and gamma chains of fibrinogen are shown separately. Each colored line represents a unique peptide. Nested peptides with a common core motif are shown in the same color. Grey bar denotes peptides with identical core motif between samples.

Results:

ACPAs (1325:04C03 and 1325:01B09) induced pain-like behavior (lasting for at least 4 weeks) and reduction of the trabecular and cortical bone thickness in the hind limbs as compared to control monoclonal antibodies (p<0.05). While no macroscopic or MRI signs of synovial inflammation were detected, MRI subclinical inflammation of the tendon sheaths was present in mice injected with ACPAs, but not in those injected with control mAb. Semi-quantitative scoring of the inflammatory tendon changes showed significant higher values in mice injected with ACPA (median of 1, range 0 to 2) than those injected with control mAb (median of 0, range 0 to 1).

Conclusion:

We show that ACPA induces pain-like behavior, bone loss and tendon sheath inflammation in mice, a model that mimics the preclinical state of ACPA positive RA.

References:

[1]Harre, U. et al. J Clin Invest (2012)

[2]Krishnamurthy, A. et al. Ann Rheum Dis (2016, 2019), JI 2019

[3]Wigerblad, G. et al. Ann Rheum Dis (2016, 2019)

[4]KleyerA, Seminars in Arthritis and Rheumatism (2016)

Disclosure of Interests:

Akilan Krishnamurthy: None declared, Yogan Kisten: None declared, Alexandra Circiumaru: None declared, Koji Sakurabas: None declared, Patrik Jarvolli: None declared, Juan Jimenez Jimenez Andrade: None declared, Peter Damberg: None declared, Heidi Wähämaa: None declared, Vivianne Malmström Grant/research support from: VM has had research grants from Janssen Pharmaceutica, Lars Klareskog: None declared, Camilla Svensson: None declared, Bence Réthi: None declared, Anca Catrina: None declared

SAT0017 METABOLIC CHANGES INDUCED BY ANTI-MALONDIALDEHYDE/MALINDIALDEHYDE-ACETALDEHYDE ANTIBODIES PROMOTE OSTEOCLAST DEVELOPMENT

Background:

Malondialdehyde (MDA) is a highly reactive compound produced by lipid-peroxidation in situations associated with oxidative stress. MDA can irreversibly modify proteins residues such as lysine, arginine and histidine. In addition, MDA adducts can further react with acetaldehyde to generate malondialdehyde-acetaldehyde (MAA) modifications. Such modifications can give rise to immunogenic neo-epitopes that are recognized by autoantibodies. In fact, anti-MDA/MAA IgG antibodies are significantly increased in the serum of patients with autoimmune diseases, such as rheumatoid arthritis (RA) (1) and systemic lupus erythematosus (2). Recently, we have shown that anti-MDA/MAA IgG antibodies are able to promote osteoclast (OC) differentiationin vitro(1).

Objectives:

To investigate the molecular mechanisms triggered by anti-MDA/MAA autoantibodies during osteoclastogenesis.

Methods:

OCs were generated from monocyte-derived macrophages in the presence of the cytokines RANK-L and M-CSF. The development of OCs was monitored by light microscopy following tartrate-resistant acid phosphatase (TRAP) staining and erosion area on synthetic calcium phosphate-coated plates. Three different recombinant human monoclonal anti-MDA/MAA antibodies, cloned from single synovial B cells of RA patients, control antibodies and Fab fragments of the antibodies were added to OC cultures. Glycolysis was inhibited by 2-deoxyglucose, and Fc-gamma receptor I or II by anti-CD64 or anti-CD16 neutralizing antibodies. IL-8 levels were measured by enzyme linked immunosorbent assay. Cellular metabolism was monitored using Seahorse XF Analyzer (extracellular acidification rate and oxygen consumption) and a colorimetric L-Lactate assay.

Results:

Lactic acid production correlated with the osteoclastogenetic effect of some but not all anti-MDA/MAA antibodies on OCs (R=0.4758, p=0.0252) suggesting an antibody-mediated regulation of glycolysis. Further, extracellular acidification (ECAR) and oxygen consumption (OCR) rate of the developing OCs were increased by the osteoclastogenic anti-MDA/MAA clones (maximum increase of 54% for the ECAR and 78% for the OCR by clone 146+:01G07, and maximum increase of 28% for the ECAR and 39% for the OCR by clone 1103:01H05), but not by the non-osteoclastogenetic anti-MDA/MAA clones or control antibodies. The glycolysis inhibitor 2-deoxyglucose completely abolished the osteoclastogenetic effect of the anti-MDA/MAA clones at drug concentrations that did not influenced baseline OC development. Fab2 fragments of the osteocalstogenetic anti-MDA/MAA clones had no effect on OC development and metabolism. In accordance with this, Fc-gamma receptor I neutralizing antibodies completely abolished the osteocalstogenetic effect of the anti-MDA/MAA clones. The osteoclastogenetic effect of the anti-MDA/MAA antibodies was independent of IL-8 production. In contrast to anti MDA/MAA antibodies, ACPA-mediated osteoclastogenesis was independent of glycolysis and Fc-gamma receptors but dependent on IL-8.

Conclusion:

Our results describe a novel glycolysis-dependent mechanism by which anti-MDA/MAA antibodies promote osteoclast development that is different from the one previously described for ACPA.

References:

[1] C. Grönwall et al. Journal of Autoimmunity 84 (2017) 29-45.

[2] C. Wang et al. Arthritis and Rheumatism 62 (2010) 2064-2072

Disclosure of Interests:

Koji Sakuraba: None declared, Akilan Krishnamurthy: None declared, Alexandra Circiumaru: None declared, Meng Sun: None declared, Vijay Joshua: None declared, Marianne Engström: None declared, Xiaowei Zheng: None declared, Cheng Xu: None declared, Khaled Amara: None declared, Vivianne Malmström Grant/research support from: VM has had research grants from Janssen Pharmaceutica, Sergiu-Bogdan Catrina: None declared, Caroline Grönwall: None declared, Bence Réthi: None declared, Anca Catrina: None declared

FRI0005 DIVERSITY OF ANTI-CITRULLINATED PROTEIN ANTIBODY COMPOSITIONS INFLUENCE SYNOVIAL FIBROBLAST REACTIVITY

Background:

Anti-citrullinated protein antibodies (ACPAs) play an important role in rheumatoid arthritis (RA) pathogenesis. We hypothesized that the effect of these antibodies is mediated by their binding to synovial fibroblasts and inducing an increased mobility of fibroblasts1.

Objectives:

In our study, we analyzed and compared fibroblast modulation by ACPA pools obtained from different patients or by a set of monoclonal ACPAs with different fine specificity that were obtained from different tissue sites.

Methods:

Synovial fibroblasts were isolated from RA patients synovial tissue biopsies. Individual polyclonal ACPA and control IgGs were purified from sera of four ACPA-positive RA patients by affinity purification on protein G and CCP-2 columns. Monoclonal antibodies were derived from memory B cell isolated from blood2, synovial fluid or bronchoalveolar lavage of RA patients. Whole antibodies and F(ab’)2 fragments were tested in fibroblast migration using IncuCyte live-cell analysis. Blocking experiments were performed with soluble citrullinated proteins in SF migration. Cross-reactivity of the antibodies to citrullinated and acetylated epitopes was tested using PAD inhibitors (Cl-amidine and GSK199), histone acetyltransferases (anacardic acid) and deacetylases (trichostatin A). Binding patterns of monoclonal ACPAs, both whole and F(ab’)2 fragments were analyzed in synovial biopsies obtained from both healthy donors and RA patients.

Results:

Three out of four tested individual ACPA were able to promote fibroblast migration. Five out of nine tested monoclonal ACPAs stimulated fibroblast migration. One of these antibodies, clone 1325:01B09 is characterized by cross-reactivity to citrullinated, homocitrullinated and acetylated targets. The effect of 1325:01B09 on fibroblast migration was completely abolished by Cl-amidine or by pre-incubating the antibody with citrullinated fibrinogen or histone but not citrullinated enolase or vimentin. Despite the cross-reactivity to acetylated epitopes, neither anacardic acid nor trichostatin A could modulate the 1325:01B09 effect on fibroblast migration. F(ab’)2 fragments of this antibody stimulated fibroblast migration and labelled podoplanin-positive fibroblasts in inflamed RA synovium similarly to the intact antibody, indicating an Fc-independent effect.

Conclusion:

The effect on fibroblast mobility was likely to be mediated by binding to citrullinated epitopes but not through Fc receptors. Detection of fibroblast modulating ACPAs in majority of RA patients indicated that fibroblasts might be key cellular targets in disease pathogenesis, although individual variability might exist in the composition of ACPA cellular targets.

References:

[1]Sun M, Rethi B, Krishnamurthy A, et al. Anticitrullinated protein antibodies facilitate migration of synovial tissue-derived fibroblasts. Ann Rheum Dis 2019;78(12):1621-31. doi: 10.1136/annrheumdis-2018-214967 [published Online First: 2019/09/05]

[2]Amara K, Lena Israelsson, Ragnhild Stålesen, et al. A Refined Protocol for Identifying Citrulline-specific Monoclonal Antibodies from Single Human B Cells from Rheumatoid Arthritis Patient Material. Bio-protocol 2019;9(16)

Disclosure of Interests:

Meng Sun: None declared, Bence Réthi: None declared, Akilan Krishnamurthy: None declared, Vijay Joshua: None declared, Alexandra Circiumaru: None declared, Marianne Engström: None declared, Caroline Grönwall: None declared, Vivianne Malmström Grant/research support from: VM has had research grants from Janssen Pharmaceutica, Khaled Amara: None declared, Lars Klareskog: None declared, Heidi Wähämaa: None declared, Anca Catrina: None declared

Biomarker analysis for UPCI 14-118: Phase II study of pembrolizumab in combination with azacitidine in patients with refractory metastatic colorectal cancer

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Background: DNA mismatch repair (MMR) proficient colorectal cancer (CRC) is resistant to immune checkpoint therapy compared to MMR deficient CRC. DNA hypomethylating agents may promote anti-tumor immune response by re-expression of cancer-testis antigen and reactivating immune genes suppressed by DNA methylation. This trial tested whether epigenetic modulation by concurrent treatment with azacitidine could enhance the anti-tumor activity of pembrolizumab in mCRC. Methods: Phase II trial was conducted to evaluate activity, safety, and tolerability of pembrolizumab in combination with azacitidine in patients with previously treated pMMR metastatic CRC. Patients received pembrolizumab 200 mg IV on day 1 and azacitidine 100 mg daily SQ injection on days 1-5 every 3 weeks. The primary endpoint of the study was ORR. Tumors were biopsied pre-treatment and on-treatment for biomarker studies. Results: 30 patients received at least one dose of therapy. One patient experienced a confirmed partial response, one experienced stable disease. ORR was 3% (1/30; 95% CI, 0.1-17%). Median PFS was 1.9 months, median OS was 6.3 months. Treatment was well tolerated with only one patient (3%) experiencing grade 3 adverse event. The patient with a PR had positive pre-treatment TILs, but no evaluable tumor from on-treatment biopsy. 2 of 6 patients who continued therapy despite PD on first restaging experienced temporary stabilization of disease later. 5 of 16 evaluable biopsy pairs demonstrated increased TILs on treatment compared to baseline; however, all of these patients experienced PD. 10 of 15 paired samples demonstrated decreased methylation of hypermethylated loci on-treatment. Clustering analysis demonstrated a correlation between pre-treatment methylation of immune activation genes with overall survival of the patients. Conclusions: Combining azacitidine and pembrolizumab is safe and tolerable for pMMR mCRC with only limited activity. DNA methylation and TIL changes are detectable after 3 cycles of therapy. DNA methylation of immune activation genes correlate with overall survival. RNA sequencing and peripheral immune cell flow cytometry are ongoing. Clinical trial information: NCT02260440.

NSABP FC-10: Phase IB study of pembrolizumab in combination with premetrexed + oaliplatin in patients (pts) with chemo-refractory metastatic colorectal cancer (mCRC)

TPS262

Background: The majority of mCRC pts are microsatellite stable (MSS), have poor intratumoral CD8+ T cell infiltration, and no clinical response to immunotherapy checkpoint inhibitors. Preclinical studies suggest that chemotherapy may synergize with anti-PD-1. In non-small cell lung cancer (NSCLC), the combination of pembrolizumab (PemB), pemetrexed (PemT), + carboplatin demonstrated synergistic activity. This study will combine PemB with PemT, then that combination + oxaliplatin (Ox). The rationale for addition of Ox to PemT is that enhanced immunogenic cell death may induce CD8+ T cell infiltration into CRC tumors and model the mechanism of cytotoxicity seen in NSCLC. Thus, the combination of PemB+ PemT + Ox may induce synergistic antitumor immune activity. Methods: This multi-center phase Ib trial is actively enrolling pts with incurable mCRC with prior treatment for mCRC including fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy, and if RAS wild-type, anti-EGFR therapy. Measurable disease by imaging (RECIST 1.1) is required. Standard ineligibility includes active infections, systemic steroid use, or other conditions contraindicating immunotherapy. Cohort 1 will receive PemB + PemT; Cohort 2 will receive PemB + PemT + dose-escalated Ox. Imaging will be performed every 6 wks. The primary aim of Cohort 1: to evaluate for safety and efficacy using doses of PemB and PemT that have been studied in NSCLC. The primary aim of Cohort 2: to evaluate the safety, tolerability, and efficacy of PemB in combination with PemT + Ox. The RP2D of the 3-drug combination will be at the MTD taking into account toxicity profiles of study therapy agents. Secondary aims: to evaluate the clinical benefit rate of the doublet and triplet combinations in pts with chemo-refractory MSS mCRC and to estimate progression-free survival and overall survival in pts with MSS mCRC treated with these combinations. The cohorts will be analyzed separately with descriptive intent only. Maximum enrollment is 33 pts. Support: Merck; Lilly; NSABP Foundation, Inc. Clinical trial information: NCT03626922.

Impact of multidisciplinary management in the diagnosis and treatment of neuroendocrine tumors (NET)

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Background: The incidence and prevalence of NETs is increasing and diagnosis and pathologic evaluation of NETs is complex. Given the new advances in local and systemic therapies, multidisciplinary management models have been suggested to assist in treatment decisions. However, scientific data showing definite change in management with multidisciplinary clinic (MDC) review is lacking. We aim to address this need in this study. Methods: 113 GI-NET patients from 2012-18 were reviewed from a dedicated MDC where patients are seen simultaneously by multiple subspecialties, and data on patient characteristics, radiology, tumor pathology and treatment strategies were collected. Change in diagnosis was defined as any change in radiographic or pathologic findings that resulted in a change in the tumor type, grade, site or stage of cancer. Change in management was defined as any recommended change in treatment approach for NETs compared to the prior treatment plan. For patients who did not have a prior treatment plan or were seen directly at MDC, a change of management was considered as yes only if there was a change in diagnosis post MDC. Results: The mean age of patients evaluated was 61, with locally advanced or metastatic disease seen in 81% of patients. Small bowel and pancreatic NETs were the most common primaries (36% each). Significant proportion of NETs were well-differentiated (72%) with < 2 mitosis/10 HPF (47.3%) and Ki-67 of < 3% (36%). Patients were referred to MDC at an average of 2.5 years from diagnosis, with 23% having the MDC as their first visit. 40% had prior resection of primary, 25% were on somatostatin analogues (SSAs) previously and 9% of patients had received prior liver directed therapy (LDT). A significant proportion of patients had change in diagnosis post MDC evaluation: change in site (7%), stage of disease (7%), tumor type (3.5%) and grade (0.1%). A change in management was recommended in 50% of patients, with SSAs recommended in 43.8%, surgery in 25.4% and LDT in 17.5% of the patients. Conclusions: The use of a dedicated MDC to manage NETs had a substantial impact in change in management in a significant percentage of patients evaluated. MDC care for patients diagnosed with NET is recommended for optimal management.

Antibody drug conjugates under investigation in phase I and phase II clinical trials for gastrointestinal cancer

INTRODUCTION

Antibody drug conjugates (ADCs) represent a developing class of anticancer therapeutics which are designed to selectively deliver a cytotoxic payload to tumors, while limiting systemic toxicity to healthy tissues. There are several ADCs which are currently in various stages of clinical development for the treatment of gastrointestinal malignancies.

AREAS COVERED

We discuss the biologic rationale and review the clinical experience with ADCs in the treatment of gastrointestinal malignancies, summarizing the pre-clinical and phase I/II clinical trial data that have been completed or are ongoing.

EXPERT OPINION

While there have been significant advances in the development of ADCs since they were first introduced, several challenges remain. These challenges include (i) the selection of an ideal antigen target which is tumor specific and internalized upon binding, (ii) selection of an antibody which has high affinity for its antigen target and low immunogenicity, (iii) selection of a potent payload which is cytotoxic at sub-nanomolar concentrations, and (iv) optimal design of a linker to confer ADC stability with limited off-site toxicity. Efforts are ongoing to address these issues and innovate the ADC technology to improve the safety and efficacy of these agents.

Phase Ib Results of the Rational Combination of Selumetinib and Cyclosporin A in Advanced Solid Tumors with an Expansion Cohort in Metastatic Colorectal Cancer

MEK inhibition is of interest in cancer drug development, but clinical activity in metastatic colorectal cancer (mCRC) has been limited. Preclinical studies demonstrated Wnt pathway overexpression in KRAS-mutant cell lines resistant to the MEK inhibitor, selumetinib. The combination of selumetinib and cyclosporin A, a noncanonical Wnt pathway modulator, demonstrated antitumor activity in mCRC patient-derived xenografts. To translate these results, we conducted a NCI Cancer Therapy Evaluation Program-approved multicenter phase I/IB trial (NCT02188264) of the combination of selumetinib and cyclosporin A. Patients with advanced solid malignancies were treated with the combination of oral selumetinib and cyclosporin A in the dose escalation phase, followed by an expansion cohort of irinotecan and oxaliplatin-refractory mCRC. The expansion cohort utilized a single-agent selumetinib "run-in" to evaluate FZD2 biomarker upregulation and KRAS-WT and KRAS-MT stratification to identify any potential predictors of efficacy. Twenty and 19 patients were enrolled in dose escalation and expansion phases, respectively. The most common adverse events and grade 3/4 toxicities were rash, hypertension, and edema. Three dose-limiting toxicities (grade 3 hypertension, rash, and increased creatinine) were reported. The MTD was selumetinib 75 mg twice daily and cyclosporin A 2 mg/kg twice daily on a 28-day cycle. KRAS stratification did not identify any differences in response between KRAS-WT and KRAS-MT cancers. Two partial responses, 18 stable disease, and 10 progressive disease responses were observed. Combination selumetinib and cyclosporin A is well tolerated, with evidence of activity in mCRC. Future strategies for concept development include identifying better predictors of efficacy and improved Wnt pathway modulation.Significance: These findings translate preclinical studies combining selumetinib and cyclosporin into a phase I first-in-human clinical trial of such a combination in patients with advanced solid malignancies. Cancer Res; 78(18); 5398-407. ©2018 AACR.

Advanced buffer materials for indoor air CO2 control in commercial buildings

In this study, we evaluated solid sorbents for their ability to passively control indoor CO₂ concentration in buildings or rooms with cyclic occupancy (eg, offices, bedrooms). Silica supported amines were identified as suitable candidates and systematically evaluated in the removal of CO₂ from indoor air by equilibrium and dynamic techniques. In particular, sorbents with various amine loadings were synthesized using tetraethylenepentamine (TEPA), poly(ethyleneimine) (PEI) and a silane coupling agent 3-aminopropyltriethoxysilane (APS). TGA analysis indicates that TEPA impregnated silica not only displays a relatively high adsorption capacity when exposed to ppm level CO₂ concentrations, but also is capable of desorbing the majority of CO₂ by air flow (eg, by concentration gradient). In 10 L flow-through chamber experiments, TEPA-based sorbents reduced outlet CO₂ by up to 5% at 50% RH and up to 93% of CO₂ adsorbed over 8 hours was desorbed within 16 hours. In 8 m³ flow-through chamber experiments, 18 g of the sorbent powder spread over a 2 m² area removed approximately 8% of CO₂ injected. By extrapolating these results to real buildings, we estimate that meaningful reductions in the CO₂ can be achieved, which may help reduce energy requirements for ventilation and/or improve air quality.

Atezolizumab: A novel PD-L1 inhibitor in cancer therapy with a focus in bladder and non-small cell lung cancers

In recent years, immunotherapy has come to the forefront as a major development in cancer treatment. Evasion of the immune system by tumor cells has been identified as one of the hallmarks of cancer and multiple therapies have been developed to counter this process. Programmed cell death 1 ligand 1 (PD-L1), a ligand to programmed cell death protein 1 (PD-1), is expressed by many cancer cells and the binding of PD-L1 to PD-1 results in the suppression of T-cell-mediated immune response against cancer cells. Atezolizumab is a monoclonal antibody that binds to PD-L1 and blocks its interaction with PD-1, thereby enhancing T-cell activity against tumor cells. Atezolizumab has been shown to be well tolerated with no dose-limiting toxicities in phase I trials. Atezolizumab was approved by the U.S. Food and Drug Administration in 2016 for the treatment of platinum-resistant metastatic non-small cell lung cancer (NSCLC) and urothelial cancer based on phase II and preliminary phase III studies that have shown significant improvement in objective response rate and median overall survival. There are 117 ongoing clinical trials of atezolizumab currently. Given its efficacy in NSCLC and urothelial carcinoma, atezolizumab holds much potential in the future of cancer therapeutics.

A phase IB study of the combination of selumetinib (AZD6244, ARRY-142886) and cyclosporin A (CsA) in patients with advanced solid tumors with an expansion cohort in metastatic colorectal cancer (mCRC)

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Background: MEK inhibition is of interest in cancer drug development. However, better strategies are needed to overcome acquired resistance to MEK inhibitors. Preclinical studies have shown Wnt pathway overexpression in KRAS mutant cell lines resistant to the MEK inhibitor, selumetinib. The combination of selumetinib and cyclosporin A (CsA), a non-canonical Wnt pathway modulator, demonstrated antitumor activity in patient-derived xenograft (PDX) models. We conducted an NCI CTEP-approved Phase I/IB trial (NCI # 9571/COMIRB # 13-2628/NCT02188264) of selumetinib and CsA combination. Biomarkers of response are being co-developed. Methods: Patients with advanced solid tumors were treated with the combination of selumetinib and CsA in dose escalation followed by an expansion cohort in patients with irinotecan and oxaliplatin-refractory mCRC (n = 20). The expansion cohort utilized a selumetinib “run-in” to evaluate efficacy in RAS-WT and RAS-MT mCRC to identify those patients most likely to respond to the combination. Results: As of January 2017, 18 patients were enrolled in the dose escalation phase and 20 patients were enrolled in the dose expansion phase. The most common adverse events and grade 3/4 toxicities were rash, hypertension, and edema. Three DLTs - Grade 3 hypertension, rash and increased creatinine were reported. The maximum tolerated dose was identified as selumetinib 75 mg BID and CsA 2 mg/kg BID on a 28-day cycle. The selumetinib “run-in” did not favor a specific RAS type. Two partial responses were noted. Sixteen patients had stable disease, and 6 patients had progression of disease as their best response to therapy. Conclusions: Selumetinib in combination with cyclosporin A appears to be well tolerated with evidence of activity in mCRC. Tumor response data are currently being updated. FZD will be evaluated as a potential biomarker of response. Clinical trial information: NCT02188264.

A phase IB study of the combination of selumetinib (AZD6244; ARRY-142886) and cyclosporin A (CsA) in patients with advanced solid tumors with an expansion cohort in metastatic colorectal cancer (mCRC)

609

Background: Targeting MEK is of interest in the development of novel agents for treatment of many malignancies. However, better strategies are needed to overcome acquired resistance to MEK inhibitors. Preclinical studies have shown Wnt pathway overexpression in KRAS mutant cell lines resistant to the MEK inhibitor, Selumetinib. The combination of selumetinib and cyclosporin A (CsA), a non-canonical WnT pathway modulator, demonstrated antitumor activity in patient-derived xenograft (PDX) models. We are conducting an NCI CTEP-approved Phase I/IB trial (NCI # 9571/COMIRB # 13-2628) of selumetinib and CsA combination. Biomarkers of response to therapy are being co-developed. We hypothesize that this combination will be safe and potentially effective in patients with mCRC and that upregulation of FZD2 may predict for sensitivity. Methods: Phase I trial with initial dose escalation investigating the combination of selumetinib and CsA in patients with advanced solid tumors (n = 18) followed by an expansion cohort in patients with irinotecan and oxaliplatin-refractory mCRC (n = 20). The expansion cohort utilizes a selumetinib “run-in” to evaluate efficacy in RAS-WT and RAS-MT mCRC to identify those patients most likely to respond to the combination. Results: 18 patients were enrolled in the dose escalation phase and 10 patients have been enrolled in the dose expansion phase as of September 2016. Grade 1 or 2 nausea and rash were reported as the most common AEs. Most commonly reported Grade 3 or 4 toxicities were hypertension, elevated liver enzymes and rash. Three DLTs were reported with Grade 3 hypertension noted at dose level 1 and 2 and grade 3 rash reported at dose level 2. The maximum tolerated dose was defined as Selumetinib 75 mg BID and CsA 2 mg/kg BID on a 28-day cycle. Two partial responses and sixteen stable disease responses have been observed. Six patients have exhibited progressive disease. Conclusions: Selumetinib in combination with cyclosporin A appears to be well-tolerated with evidence of activity in solid tumors. Expansion cohort will complete enrollment this month. Clinical trial information: NCT02188264.

The increasing challenge of never smokers with adenocarcinoma lung: Need to look beyond tobacco exposure

BACKGROUND

Lung cancer continues to remain as one of the leading causes of morbidity and mortality worldwide, despite the decreasing trends in smoking prevalence worldwide. An earlier study from the authors' institute reported the increasing trends of "Nonsmoking associated lung cancers."

MATERIALS AND METHODS

All consecutive histologically confirmed patients with lung cancer who presented to the outpatient department over a year (November 2014-October 2015) were included in this current prospective study.

RESULTS

Seven hundred and thirteen patients presented with clinicoradiologically suspicious findings of lung cancer in the said period. A pathological confirmation of lung cancer could be ascertained in 495 patients, and this cohort was further analyzed. The mean age of presentation was 57.76 years; the male to female ratio was approximately 2.5:1. Interestingly, 55.35% of the patients were nonsmokers. Adenocarcinoma (63%) was the predominant histology. Never smokers, both among men (P = 0.02) and women (P = 0.001), presented more frequently with adenocarcinoma histology. Further, 84.9% (45/53) of rural and 76.1% (19/25) of urban women who were never smokers reported exposure to indoor air pollution (secondhand smoke/fuel used for cooking purposes) which was significantly associated with adenocarcinoma histology.

CONCLUSION

Our study confirmed our initial observation of the changing epidemiology of lung cancer in the Indian subcontinent, paralleling the global trends of rise in adenocarcinoma. Lung cancer in never smokers outnumbering that among smokers was another interesting observation. The take-home message for both the clinicians as well as the policymakers is to study factors beyond tobacco exposure to understand the direction of the current lung cancer epidemic.

Chemotherapy delivery for resected colorectal cancer liver metastases: Management and outcomes in routine clinical practice

BACKGROUND

International guidelines recommend peri-operative chemotherapy for patients with resectable colorectal cancer liver metastases (CRCLM). Chemotherapy delivery in routine practice is not well described.

METHODS

All cases of CRC who underwent resection of LM in 2002-2009 were identified using the population-based Ontario Cancer Registry. Electronic treatment records identified chemotherapy delivered within 16 weeks before or after hepatectomy. All pathology reports were reviewed to describe extent of LM. Modified Poisson regression was used to evaluate factors associated with chemotherapy delivery. Cox proportional hazards model and propensity score analysis were used to explore the association between post-operative chemotherapy and cancer-specific (CSS) and overall (OS) survival.

RESULTS

We identified 1310 patients. Sixty-two percent of cases (815/1310) received peri-operative chemotherapy; 25% (200/815) pre-operative, 45% (366/815) post-operative, and 31% (249/815) pre- and post-operative. Utilization of chemotherapy increased over time from 51% in 2002 (57/112) to 73% in 2009 (157/216, p < 0.001). Fifty-four percent of patients received FOLFOX, 41% FOLFIRI, and 10% 5-FU monotherapy. Factors that were independently associated with greater utilization of post-operative chemotherapy included younger age (p < 0.001), female sex (p = 0.050), shorter disease-free interval (p = 0.006), and no prior adjuvant chemotherapy (p < 0.001). Utilization of chemotherapy varied substantially across geographic regions (from 24% to 71%, p = 0.001). Post-operative chemotherapy was associated with improved CSS (HR 0.58, 95%CI 0.44-0.76) and OS (HR 0.49, 95%CI 0.38-0.61); results were consistent in propensity score analysis.

CONCLUSION

Utilization of chemotherapy for resected CRCLM in routine practice has evolved with emerging evidence. Post-operative chemotherapy is associated with improved survival in the general population.

Etanercept decreases synovial expression of tumour necrosis factor-α and lymphotoxin-α in rheumatoid arthritis

OBJECTIVES

Etanercept is an effective tumour necrosis factor (TNF)-α inhibitor drug with the unique ability to block not only TNF-α but also lymphotoxin (LT)-α, at least in vitro. We aimed to investigate the in vivo effect of etanercept on synovial expression of TNF-α and LT-α.

METHOD

Synovial biopsies from 12 rheumatoid arthritis (RA) patients started on etanercept and 11 RA patients started on infliximab were obtained at baseline and 8 weeks after treatment initiation. Synovial expression of TNF-α and LT-α was evaluated by immunohistochemistry followed by computer-assisted image analysis. Differences between paired samples were analysed by the Wilcoxon test and between groups by the Mann-Whitney test. A p-value < 0.05 was considered statistically significant.

RESULTS

Six out of the 12 of the patients started on etanercept achieved an American College of Rheumatology (ACR)50 response. Macroscopic evaluation of the joints during arthroscopy revealed a significant decrease of local inflammation mainly in good ACR50 responders. Synovial expression of both LT-α and TNF-α decreased but the differences did not reach statistical significance at a group level. By contrast, a significant decrease in both LT-α and TNF-α was observed when only good ACR50 responders were analysed. Despite higher levels of baseline synovial TNF-α in the good responders, neither baseline LT-α nor TNF-α could predict clinical response after 8 weeks. A decreasing trend of the synovial levels of LT-α was also observed in good responders to infliximab, but the difference did not reach statistical significance.

CONCLUSIONS

Etanercept treatment modulates the synovial expression of both TNF-α and LT-α in vivo, a mechanism that might partly explain its clinical efficacy in RA.