Multicenter, randomized phase II study of neoadjuvant pembrolizumab plus chemotherapy and chemoradiotherapy in esophageal adenocarcinoma (EAC)

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Background: Recent transformative studies in the treatment of EAC support adjuvant nivolumab for patients with residual disease following neoadjuvant chemoradiotherapy (CRT) (Checkmate 577) and pembrolizumab (P) with chemotherapy in untreated metastatic disease (Keynote 590). We hypothesized that pre-operative P combined with CRT can further improve outcomes in patients with locally advanced EAC. Methods: Patients with cT3-4Nx or T2N1 M0 EAC or gastroesophageal junction (GEJ) adenocarcinoma eligible for curative surgery were randomized (1:1) to receive either full-dose paclitaxel (T)/ carboplatin (C) or T/C + P induction therapy. All patients then received CRT with weekly T/C, RT 41.4Gy in 23 fractions, and P every 3 weeks. Following resection, patients received P for one year. The primary endpoint is rate of major pathologic response (MPR), defined as pathologic complete response or near complete response ( < 10% residual cancer), with 80% power and 0.1 one-sided significance level to detect the difference between a MPR proportion of 30% (historical control) and an alternative hypothesis of 47% (with preoperative P). Tissue was collected for tumor immune microenvironment (TIME) analysis including bulk and single cell RNA(scRNA) expression analysis, DNA sequencing, and flow cytometry. Results: From 8/4/17 to 10/26/20, 40 patients were enrolled: median age 68 [38-81], male 32, esophagus/GEJ type I (n = 16), GEJ II/III (n = 24). CRT was well tolerated, with no grade 3-4 adverse events attributed to P. Notable toxicity included grade 3-4 pneumonitis (13%), anastomotic leak (13%), infection (35%). In 31 evaluable patients to date, the MPR rate was 50.0% (95% CI, 32.7%-67.3%). 1-yr disease free survival was 100% for patients with MPR vs. 31.8% without MPR, p = 0.002. Esophageal/GEJ type I cancers had a significantly higher MPR rate when compared with GEJ type II/III (76.9% vs 37.5%, p = 0.03). scRNA seq on > 100,000 tumor cells revealed EAC/GEJ type I had higher infiltration of activated dendritic cells (p = 0.12), whereas GEJ tumors have significantly higher infiltration of activated B cells (p = 0.02). Conclusions: The addition of P to preoperative CRT for EAC is safe and associated with a significantly higher MPR rate compared to historical data. We found MPR to be significantly enriched in EAC/GEJ type I tumors compared with GEJ II/III, associated with important differences in the baseline tumor immune microenvironment. Clinical trial information: NCT02998268.

Identifying the prevalence of undiagnosed cardiovascular disease risk factors in healthy Indians

Funding Acknowledgements

Type of funding sources: None.

Introduction

 

Cardiovascular disease (CVD) including heart disease and stroke, is the leading cause of death globally and in India. 

The importance of primary prevention, defined as interventions designed to modify adverse risk factors with the goal of preventing an initial CVD event has been established beyond doubt by several population based studies in healthy individuals.

While there have been many studies defining the high prevalence in CVD risk factors in Indian population, this study sought to determine the prevalence of undiagnosed modifiable CVD risk factors in healthy individuals. 

Methods

The  cross sectional, analytical study was carried out at the hospitals, from 1st April 2015 to 31st dec 2017. Subjects between 18 - 70 years of age who were healthy and were undergoing health checkup were included in the study. A total of 5000 patients were screened, those having existing CVD risk factors were excluded from the study. 

This study was approved by the institutional ethics committee of the hospital. Written informed consent was obtained from all subjects. The data collection record sheet was prepared based on validated and standardized questionnaires which was used to enter all data. 

Physical examination for vitals and BMI was done by qualified physicians. Blood investigations were done for diabetes and dyslipidemia and thyroid dysfunction. ACC/AHA criteria was used for diagnosis of  hypertension, ADA criteria for diabetes. Joint British society 3 risk score and ASCVD risk score was calculated using standard calculators.

Results

At screening, 4998 participants aged ≥18 years were approached to participate in study. The study population included 2705 men (68.1%) and 1265 women (31.9%) with a mean age of 68± 18.8 years. The most prevalent risk factor was overweight and obesity (71.2%).

The prevalence of undiagnosed HTN was 73.3%, undiagnosed pre-diabetes was 24.9% and undiagnosed diabetes was 28.3%. Out of total, 44.3% subjects had high level of low-density lipoprotein and 36.6% subjects had low level of high-density lipoprotein, 20.1% subjects had high level of very-low density lipoprotein (VLDL) and 17.3% subjects had high level of triglyceride.

Tobacco smoking was present in 7.7% of the population. The risk estimation predicted 29.1% of the study participants to have more than 10% risk of heart attack/stroke risk at 10 years.

Conclusion

Our study reveals a fairly good snapshot of CVDs risk factors in healthy general population. Increased prevalence of high BMI, undiagnosed HTN, diabetes, dyslipidemia was present in our study population. 

The population had significantly high predicted risk of heart attack/stroke. These findings warrant the need of community based life style modifications, regular health checkup for healthy population for early detection and modification of CVD risk factors.

Can We Avoid Axillary Lymph Node Dissection (ALND) in Patients with 1-2 Positive Sentinel/Low Axillary Lymph Nodes (SLN/LAS+) in the Indian Setting?

The ACOSOG Z0011 study, heralded as a "practice changing" trial, suggested that women with T1-2 breast cancer with 1-2 SLN+, undergoing breast conservation therapy, need not be offered further ALND. However, whether these results are applicable to all women in the Indian setting, it remains debatable. A retrospective audit of all cN0 operated from 2013 to 2018 was conducted. We analyzed the percentage of additional LN positive (LN+) in the ALND group and compared it to the ACOZOG Z11 trial. Of the 2350 cN0 with EBC who underwent LAS, 687 (29%) had positive lymph nodes on final histopathology. Five hundred ninety-seven (86.9%) patients had 1-2 LN+, 40 (5.8%) patients had 3 LN+, and 50 (7.3%) had 4 or more nodes positive. Demographic features in the ACOSOG Z11 are different from those in our study, looking at ACOZOG Z11 versus our cohort-median pT 1.7 cm versus 3 cm, 45% micrometastasis versus 99.16% macrometastasis, and 28-30% grade 3 tumors versus 73.7%. In our cohort 31.82% of the 1-2 LN positive had additional LN+ on ALND. Keeping in mind the difference in clinicopathological features between our cohort and that of ACOZOG Z0011 and that 31.82% of women had additional LN+ on ALND, it may not be appropriate to apply the results of the ACOSOG Z0011 trial directly to our general population. Possibly, only a select subset of patients who match the trial population of the ACOSOG Z11 could be offered observation of the axilla and validated nomograms can be used to identify high-risk patients.

Impact of antibiotic use on response to treatment with immune checkpoint inhibitors

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Background: There is an emerging evidence that the gut microbiome may influence anti-tumor immune response during treatment with checkpoint inhibitors (CPIs). A number of factors can cause gut microbiome dysbiosis including the use of antibiotics (ABX). We hypothesized that the use of ABX during immunotherapy can adversely affect the efficacy of CPIs. We explored the prevalence of ABX use amongst patients (pts) using CPIs, and whether the use of ABX influences the response to CPIs. Methods: We performed an institutional retrospective review of all the pts treated with CPIs from 2/2015-3/2018. A patient was considered to have used ABX if he or she was prescribed ABX within 6 months before or after, initiating CPIs. Statistical analysis was done using logistic regression with overall response rate (ORR) (CR, PR and SD) as the outcome. 9 separate analyses were done: one for each temporality (30 days, 60 days, 6 months) and use-order (before, after, neither) combination. Odds ratios for ORR as univariate analysis, and adjusted for age and sex; and adjusted for age, sex, and tumor type were calculated. Results: Out of 242 pts, 111 were lung, 36 bladder, 35 renal, 16 gastrointestinal and 44 other cancers. 50% (121) pts received nivolumab, 28% (68) pembrolizumab and 21% (52) atezolizumab. 75%, 46% and 32% of the pts received ABX within 6 months, 60 days and 30 days of starting CPIs. Only ABX use in the first 30- or 60-days following CPI initiation was associated with inferior ORR (OR 0.42 [95% CI:0.23,0.76] p = 0.005 for 60-days). ABX use prior to initiation of CPI at any time point, or ABX use in the first 6 months of CPI use did not impact CPI efficacy, Table 1. Conclusions: ABX use within the first 60 days of starting CPI therapy is prevalent (32%). This study suggests that the use of ABX within 60 days following initiation of CPIs significantly negatively impacts the ORR. Unnecessary usage of ABX should be avoided, especially during the early phase of starting CPIs. [Table: see text]

Abstract 3489: Elucidation of taxane resistance in prostate cancer through RNA-Seq analysis of circulating tumor cells

Prostate cancer is the most commonly diagnosed male cancer in the United States. Taxanes are the only established chemotherapy drugs proven to be effective in improving survival of men with advanced prostate cancer through disruption of the AR-signaling axis downstream of microtubule stabilization. However, there is significant heterogeneity in how patients respond to taxanes and most patients ultimately become refractory due to the development of drug resistance. Currently, the molecular basis of clinical taxane resistance in PC is poorly understood. Prostate cancer circulating tumor cells (P-CTCs) are often found in the peripheral blood of patients suffering from metastatic prostate cancer and have been clinically used as prognostic biomarker for metastatic progression and treatment outcome. The objective of this study is to identify clinically relevant mechanisms of taxane resistance through conducting RNA-Seq analysis in P-CTCs isolated from patients before, during and after they become refractory to taxane chemotherapy.

To show feasibility of RNA-Seq experiments with limiting samples such as CTCs and given the presence of contaminating leucocytes, a pilot experiment was performed in which limiting numbers of prostate cancer cells (LNCaP) either pure or enriched following spiking into healthy donor blood, were analyzed by RNA-Seq. Matching healthy donor blood processed with the same enrichment protocol was used as germline control as well as control for the presence of contaminating leucocytes following CTC enrichment. Trimmed reads were aligned to human reference genome (hg38) using STAR. Determination of Fragments Per Kilobase of exon per Million mapped fragments (FPKM) was performed using Cufflinks and heat map was built based on the value of log10(FPKM+1). Gene expression analysis showed that markers of prostate (such as AR, PSMA, KLK3, KLK2, and AMACR) or epithelial lineage (such as EpCAM, CDH1, KRT8 and KRT18) were detected in both pure LNCaP cells-regardless of amount- as well as limited number of captured LNCaP cells in the presence of contaminating leucocytes. In contrast, healthy donor blood was negative for the prostate and epithelial lineage markers and positive for the leucocyte specific markers (such as CD45 and CD16). Gene set enrichment analysis (GSEA) indicated significant enrichment for Andorgen response, MYC, MTOR and RB related pathways in pure and captured LNCap cells compared with healthy donor blood. These data clearly show that by using RNA-Seq we can detect the prostate and epithelial specific gene signatures of limited number of spiked prostate cancer cells using the microfluidic device. Ongoing work includes RNA-Seq analysis of P-CTCs isolated from patients before and after taxane treatment, in order to detect differentially expressed genes, pathways, and potentially driver somatic mutations associated with clinical taxane resistance.

Citation Format: Jiaren Zhang, Ada Gjyrezi, Prashant Thakkar, Giuseppe Galletti, Akanksha Verma, Olivier Elemento, Paraskevi Giannakakou. Elucidation of taxane resistance in prostate cancer through RNA-Seq analysis of circulating tumor cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3489.

To evaluate and compare the efficacy of combined sucrose and non-nutritive sucking for analgesia in newborns undergoing minor painful procedure: a randomized controlled trial

OBJECTIVE

The objective of this study was to evaluate and compare the efficacy of combined sucrose and non-nutritive sucking (NNS) for analgesia in newborn infants undergoing heel-stick procedures.

STUDY DESIGN

This randomized control trial was conducted in the neonatal intensive care unit of a tertiary care hospital over a period of 1 year. One hundred and eighty full-term neonates with birth weight >2200 g and age >24 h were randomized to one of four interventions administered 2 min before the procedure: 2 ml of 30% sucrose (group I, n=45) or NNS (group II, n=45) or both (group III, n=45) or none (group IV, n=45). Primary outcome was composite score based on Premature Infant Pain Profile (PIPP) score.

RESULT

Baseline variables were comparable among the groups. Median (interquartile range) PIPP score was 3 (2 to 4) in group III as compared with 7 (6.5 to 8) in group I, 9 (7 to 11) in group II and 13 (10.5 to 15) in group IV. Group III had significant decrease in the median PIPP score compared with other groups (P=0.000). Median PIPP score also decreased significantly with any intervention as compared with no intervention (P=0.000).

CONCLUSION

Sucrose and/or NNS are effective in providing analgesia in full-term neonates undergoing heel-stick procedures, with the combined intervention being more effective compared with any single intervention.

Identification of low abundance microbiome in clinical samples using whole genome sequencing

Identifying the microbiome composition from primary tissues directly affords an opportunity to study the causative relationships between the host microbiome and disease. However, this is challenging due the low abundance of microbial DNA relative to the host. We present a systematic evaluation of microbiome profiling directly from endoscopic biopsies by whole genome sequencing. We compared our methods with other approaches on datasets with previously identified microbial composition. We applied this approach to identify the microbiome from 27 stomach biopsies, and validated the presence of Helicobacter pylori by quantitative PCR. Finally, we profiled the microbial composition in The Cancer Genome Atlas gastric adenocarcinoma cohort.

Identification of the gastric microbiome from endoscopic biopsy samples using whole genome sequencing

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Background: H. pylori is the primary risk factor for gastric cancer (GC). However, virtually all infected patients do not develop GC, and H. pylori eradication does not reduce GC risk. We established a whole genome sequencing (WGS) pipeline to detect the gastric microbiome from small endoscopic samples directly. With it, we are not only be able to accurately detect H. pylori infection in GC, but also examine the microbiome in samples from other malignancies. Methods: Patients (pts) undergoing upper endoscopy without chronic inflammatory disease or chronic NSAID use were eligible for participation, categorized as follows: (1) active infection (H. pylori identified on biopsy, or positive CLOtest), (2) prior infection (previous H. pylori treatment, or ELISA IgG positive), and (3) gastric cancer. Endoscopic biopsies from 3 locations in the antrum/body were freshly frozen for WGS on a HiSeq2500 platform at ~10X coverage. Our customized computational pipeline successively removes human sequences, with remaining un-mapped reads aligned to 1,400 unique bacteria genomes. Results: 16 biopsy samples taken from 10 pts were sequenced. All H. pylori positive samples detected by our pipeline have been successfully validated by qPCR. Surprisingly, H. pylori was identified in previously treated pts. We also applied our pipeline to control samples to evaluate the performance of bacterial identification. Negative sample are blood samples from HapMap projects with human DNA only. In contrast, positive samples are bacteria enriched samples from Human Microbiome Project. Our identifications matched the previously reported results. Finally, we profiled 37 gastric cancer tumors and matching normal WGS samples from TCGA and found that 40% of them are H. pylori positive. This result is a novel discovery that was not reported in the TCGA GC study. Conclusions: This is the first demonstration of detailed unbiased microbiome detection performed from gastric endoscopic biopsy samples using WGS. We found that standard treatment does not always eradicate H. pylori possibly explaining why H. pylori treatment fails to reduce cancer risk. We also found that ~40% of gastric cancers have evidence of persistent H. pylori bacterial content.

Efficacy and safety over 26 weeks of an oral treatment strategy including sitagliptin compared with an injectable treatment strategy with liraglutide in patients with type 2 diabetes mellitus inadequately controlled on metformin: a randomised clinical trial

AIMS/HYPOTHESIS

The aim of this work was to compare treatment intensification strategies based on orally administered vs injectable incretin-based antihyperglycaemic agents in patients with type 2 diabetes mellitus on metformin monotherapy.

METHODS

In a 26 week, open-label study, 653 patients (baseline HbA1c = 8.2% [66 mmol/mol]) were randomised at 111 sites in 21 countries in a 1:1 ratio to a strategy using oral agents (starting with sitagliptin 100 mg/day) or a strategy using the injectable drug liraglutide starting at a dose of 0.6 mg/day, up-titrated to 1.2 mg/day after 1 week. The following patients with type 2 diabetes mellitus were recruited for the study: those aged 18-79 years, on a stable dose of metformin monotherapy ≥1,500 mg/day for ≥12 weeks, with an HbA1c ≥7.0% (53 mmol/mol) and ≤11.0% (97 mmol/mol) and a fasting fingerstick glucose (FFG) <15 mmol/l (<270 mg/dl) at the randomisation visit, deemed capable by the investigator of using a Victoza pen injection device (containing 6 mg/ml liraglutide; Novo Nordisk, Bagsværd, Denmark). Women taking part in the study agreed to remain abstinent or use an acceptable method of birth control during the study. Randomisation was performed via a computer-generated allocation schedule using an interactive voice response system. After 12 weeks, patients on sitagliptin with HbA1c  ≥ 7.0% (53 mmol/mol) and fasting glucose >6.1 mmol/l had their treatment intensified with glimepiride; patients on liraglutide with HbA1c  ≥ 7.0% (53 mmol/mol) had the dose up-titrated to 1.8 mg/day. The primary analysis assessed whether the strategy using oral drugs was non-inferior to that using an injectable drug regarding HbA1c change from baseline at week 26 using a per-protocol (PP) population and a non-inferiority margin of 0.4%.

RESULTS

In the PP population (522 patients included: oral strategy, n = 269; injectable strategy, n = 253) antihyperglycaemic therapy was intensified at week 12 in 50.2% and 28.5%, respectively. HbA1c decreased over 26 weeks in both treatment strategy groups, with a larger initial reduction at week 12 in the injectable strategy group. The LS mean change in HbA1c at week 26 was -1.3% (95% CI -1.4, -1.2) in the oral strategy group and -1.4% (95% CI -1.5, -1.3) in the injectable strategy group; the study met the non-inferiority criterion. Both treatment regimens were generally well tolerated; hypoglycaemia was reported more often with the oral strategy, while nausea, vomiting, diarrhoea and abdominal pain were reported more often with the injectable strategy.

CONCLUSIONS/INTERPRETATION

An oral, incretin-based treatment strategy with sitagliptin and, if needed, glimepiride may be a good approach in many patients with type 2 diabetes mellitus for managing inadequate glycaemic control on metformin monotherapy, as compared with an injectable treatment strategy with liraglutide. The oral and injectable strategies had similar effects on HbA1c and had good overall tolerability. Trial registration ClinicalTrials.gov NCT01296412 Funding The study was sponsored by Merck Sharp & Dohme Corp., a subsidiary of Merck and Co., Inc., Whitehouse Station, NJ, USA.

Drug susceptibility testing of Mycobacterium tuberculosis against second-line drugs using the Bactec MGIT 960 System

OBJECTIVE

To establish the critical test concentrations for seven second-line anti-tuberculosis drugs in the Bactec Mycobacterial Growth Indicator Tube (MGIT) 960 TB system and to evaluate its efficacy compared to the Bactec 460 TB system.

DESIGN

This study was carried out in three phases. In Phase I, pan-susceptible strains were tested to establish the minimum inhibitory concentration; in Phase II, mostly resistant strains were tested to determine a critical test concentration; and in Phase III, actual clinical isolates were tested to validate the optimal critical concentrations established in Phases I and II.

RESULTS

The critical concentrations established for seven second-line drugs with the Bactec MGIT 960 system are amikacin 1.0 microg/ml, capreomycin 2.5 microg/ml, kanamycin 2.5 microg/ml, ofloxacin 2.0 microg/ml, moxifloxacin 1.0 microg/ml, ethionamide 5.0 microg/ml and para-amino salicylic acid 4.0 microg/ml.

CONCLUSION

The Bactec MGIT 960 System is an accurate and reliable method for rapid drug susceptibility testing (DST) of Mycobacterium tuberculosis against second-line drugs. In the present study, few of the strains were resistant to fluoroquinolones and further DST for this group is required.