A Multi-Arm Two-Stage (MATS) design for proof-of-concept and dose optimization in early-phase oncology trials

The Project Optimus initiative by the FDA's Oncology Center of Excellence is widely viewed as a groundbreaking effort to change the status quo of conventional dose-finding strategies in oncology. Unlike in other therapeutic areas where multiple doses are evaluated thoroughly in dose ranging studies, early-phase oncology dose-finding studies are characterized by the practice of identifying a single dose, such as the maximum tolerated dose (MTD) or the recommended phase 2 dose (RP2D). Following the spirit of Project Optimus, we propose an Multi-Arm Two-Stage (MATS) design for proof-of-concept (PoC) and dose optimization that allows the evaluation of two selected doses from a dose-escalation trial. The design assesses the higher dose first across multiple indications in the first stage, and adaptively enters the second stage for an indication if the higher dose exhibits promising anti-tumor activities. In the second stage, a randomized comparison between the higher and lower doses is conducted to achieve PoC and dose optimization. A Bayesian hierarchical model governs the statistical inference and decision making by borrowing information across doses, indications, and stages. Our simulation studies show that the proposed MATS design yield desirable performance. An R Shiny application has been developed and made available at https://matsdesign.shinyapps.io/mats/.

SPA: Single patient acceleration in oncology dose-escalation trials

Efficient identification of the optimal dose and dosing scheme is one of the most critical and challenging tasks in early-phase oncology trials. The results are far-reaching because advancing a sub-optimal dose to late-stage development may not only jeopardize patients' safety or fail to deliver desired efficacy, but also be costly to sponsors as refined doses must be evaluated further before seeking regulatory approval. A good dose-escalation design is anticipated to yield high accuracy of selecting the correct dose while using fewer patients and keeping the trial duration short. Recently, treating a single patient at each lower dose level until certain events are triggered to switch to larger cohorts has gained much popularity. We name this approach "Single Patient Acceleration" (SPA), which is essentially a variant of the Accelerated Titration Design (ATD) by Simon et al. [25]. Although literature on novel dose-escalation methods is abundant in the past decade, there is a surprisingly lack of research on evaluating the ATD/SPA framework. In this article, we conduct comprehensive simulations to evaluate the performance of dose-escalation designs with or without SPA, and show that SPA improves design efficiency with similar or better accuracy to those without the "single patient" component under certain circumstances (e.g., slow initial enrollment, or the true maximum tolerated dose is at higher candidate dose levels). Potential safety concerns as a cost of efficiency improvement are also investigated in a quantitative manner to illustrate a comprehensive benefit-risk profile of SPA. Practical considerations and recommendations in using SPA are also discussed.

Phase 1 Expansion Cohort of Ramucirumab Plus Pembrolizumab in Advanced Treatment-Naive NSCLC

INTRODUCTION

Data of first-line ramucirumab plus pembrolizumab treatment of programmed death-ligand 1 (PD-L1)-positive NSCLC (cohort E) are reported (NCT02443324).

METHODS

In this multicenter, open-label phase 1a/b trial, patients received ramucirumab 10 mg/kg and pembrolizumab 200 mg every 21 days for up to 35 cycles. PD-L1 positivity was defined as tumor proportion score (TPS) greater than or equal to 1%. Exploratory NanoString biomarker analyses included three T-cell signatures (T-cell-inflamed, Gajewski, and effector T cells) and CD274 gene expression.

RESULTS

Cohort E included 26 patients. Treatment-related adverse events of any grade occurred in 22 patients (84.6%). Treatment-related adverse events of grade greater than or equal to 3 were reported in 11 patients (42.3%); the most frequent was hypertension (n = 4, 15.4%). Objective response rate was 42.3% in the treated population and 56.3% and 22.2% for patients with high (TPS ≥ 50%) and lower levels (TPS 1%-49%) of PD-L1 expression, respectively. Median progression-free survival (PFS) in the treated population was 9.3 months, and 12-month and 18-month PFS rates were 45% each. Median PFS was not reached in patients with PD-L1 TPS greater than or equal to 50% and was 4.2 months in patients with PD-L1 TPS 1% to 49%. Median overall survival was not reached in the treated population, and 12-month and 18-month overall survival rates were 73% and 64%, respectively. Biomarker data suggested a positive association among clinical response, three T-cell signatures, CD274 gene expression, and PD-L1 immunohistochemistry.

CONCLUSIONS

First-line therapy with ramucirumab plus pembrolizumab has a manageable safety profile in patients with NSCLC, and the efficacy signal seems to be strongest in tumors with high PD-L1 expression.

Ramucirumab and durvalumab for previously treated, advanced non-small-cell lung cancer, gastric/gastro-oesophageal junction adenocarcinoma, or hepatocellular carcinoma: An open-label, phase Ia/b study (JVDJ)

BACKGROUND

Emerging evidence supports combining immune checkpoint inhibitors (ICIs) with conventional or targeted therapies to enhance ICI antitumour activity and broaden the spectrum of patients who respond to ICIs. Here, we present the safety and preliminary efficacy of ramucirumab, an anti-VEGFR2 IgG1, plus durvalumab, an anti-PD-L1 IgG1, in previously treated patients with advanced non-small-cell lung cancer (NSCLC), gastric/gastro-oesophageal junction adenocarcinoma (gastric/GEJ), or hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

A 25-centre, phase Ia/b single-arm, non-randomised, multi-cohort study was undertaken in patients with advanced/metastatic disease, Eastern Cooperative Oncology Group performance status, 0-1, progression on prior therapy, no prior ramucirumab or immunotherapy and any PD-L1 status. Patients received ramucirumab (10 mg/kg) plus durvalumab (1125 mg) intravenously Q3W (NSCLC), or ramucirumab (8 mg/kg) plus durvalumab (750 mg) Q2W (gastric/GEJ, HCC).

RESULTS

Phase Ia treatment was found safe for phase Ib expansion; final enrolment was NSCLC (n = 28), gastric/GEJ (n = 29), HCC (n = 28). Grade ≥3 treatment-related adverse events occurred in 32.1%, 37.9% and 42.9% of patients, respectively. The most common were fatigue (35.7%), hypertension (34.5%) and diarrhoea (28.6%), respectively. Two patients died owing to an adverse event; one was treatment-related (hepatitis acute, HCC cohort). Objective response rate was 11% for NSCLC and HCC and 21% for gastric/GEJ. Median progression-free survival and overall survival were, respectively, 2.7 and 11 months in NSCLC; 2.6 and 12.4 months in gastric/GEJ; 4.4 and 10.7 months in HCC, with more prolonged survival in patients with high PD-L1 expression.

CONCLUSION

Ramucirumab/durvalumab exhibited manageable safety. The combination showed antitumour activity in all cohorts, particularly in patients with high PD-L1 expression.

A comparison between electrospinning and rotary-jet spinning to produce PCL fibers with low bacteria colonization

One of the important components in tissue engineering is material structure, providing a model for fixing and the development of cells and tissues, which allows for the transport of nutrients and regulatory molecules to and from cells. The community claims the need for new materials with better properties for use in the clinic. Poly (ε-caprolactone) (PCL) is a biodegradable polymer, semi crystalline, with superior mechanical properties and has attracted an increasing interest due to its usefulness in various biomedical applications. Herein, two different methods (electrospinning versus rotary jet spinning) with different concentrations of PCL produced ultra thin-fibers each with particular characteristics, verified and analyzed by morphology, wettability, thermal and cytotoxicity features and for bacteria colonization. Different PCL scaffold morphologies were found to be dependent on the fabrication method used. All PCL scaffolds showed greater mammalian cell interactions. Most impressively, rotary-jet spun fibers showed that a special rough surface decreased bacteria colonization, emphasizing that no nanoparticle or antibiotic was used; maybe this effect is related with physical (scaffold) and/or biological mechanisms. Thus, this study showed that rotary jet spun fibers possess a special topography compared to electrospun fibers to reduce bacteria colonization and present no cytotoxicity when in contact with mammalian cells.

Ramucirumab plus pembrolizumab in patients with previously treated advanced non-small-cell lung cancer, gastro-oesophageal cancer, or urothelial carcinomas (JVDF): a multicohort, non-randomised, open-label, phase 1a/b trial

BACKGROUND

Pre-clinical and clinical evidence suggests that simultaneous blockade of VEGF receptor-2 (VEGFR-2) and PD-1 or PD-L1 enhances antigen-specific T-cell migration, antitumour activity, and has favourable toxicity. In this study, we aimed to assess the safety and preliminary antitumour activity of ramucirumab (an IgG1 VEGFR-2 antagonist) combined with pembrolizumab (an IgG4 PD-1 antagonist) in patients with previously treated advanced gastric or gastro-oesophageal junction adenocarcinoma, non-small-cell lung cancer, or urothelial carcinoma.

METHODS

We did a multicohort, non-randomised, open-label, phase 1a/b trial at 16 academic medical centres, hospitals, and clinics in the USA, France, Germany, Spain, and the UK. We enrolled adult patients aged 18 years or older with histologically confirmed gastric or gastro-oesophageal junction adenocarcinoma (cohorts A and B), non-small-cell lung cancer (cohort C), or urothelial carcinoma (cohort D), whose disease had progressed on one or two lines of previous therapy (for those with gastric or gastro-oesophageal junction adenocarcinoma) or one to three lines of previous therapy (for those with non-small-cell lung cancer and urothelial carcinoma) that included platinum (for all tumour types) or fluoropyrimidine or both (for gastric or gastro-oesophageal junction adenocarcinoma). Eligibility criteria included presence of measurable disease and an Eastern Cooperative Oncology Group performance status of 0-1. Patients with previously untreated gastric or gastro-oesophageal junction adenocarcinoma and non-small-cell lung cancer were also enrolled (in two additional separate cohorts); the results for these cohorts will be reported separately. The first 21-day treatment cycle was a dose-limiting toxicity observation period (phase 1a; safety run-in), followed by a phase 1b cohort expansion stage. Pembrolizumab 200 mg was administered intravenously on day 1, and intravenous ramucirumab was administered at 8 mg/kg on days 1 and 8 for cohort A or at 10 mg/kg on day 1 for cohorts B, C, and D, every 3 weeks, until disease progression or other discontinuation criteria were met. The primary endpoint was the safety and tolerability of ramucirumab in combination with pembrolizumab assessed by the incidence of adverse events in both phase 1a and 1b and as dose-limiting toxicities during phase 1a. The safety and activity analysis set included all patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, number NCT02443324, and is no longer enrolling patients.

FINDINGS

Between July 30, 2015 and June 24, 2016, we enrolled and treated 92 patients (41 with gastric or gastro-oesophageal junction adenocarcinoma, 27 with non-small-cell lung cancer, and 24 with urothelial carcinoma). Median follow-up was 32·8 months (IQR 28·1-33·6). During the first cycle of treatment (phase 1a safety run-in; n=11), one patient with gastro-oesophageal junction adenocarcinoma who received the 8 mg/kg dose of ramucirumab had grade 3 abdominal pain, colitis, hepatitis, interstitial lung disease, and jaundice, and grade 4 cholestasis, and died on treatment on day 40; the death was deemed related to progressive disease. No additional dose-limiting toxicities occurred and the decision was made to maintain the full planned doses of ramucirumab and pembrolizumab in phase 1b (n=81). Treatment-related adverse events occurred in 75 (82%) of 92 patients, the most common of which was fatigue (in 33 patients [36%]), predominantly of grade 1 or 2 severity. 22 patients (24%) had one or more treatment-related adverse events of grade 3 or worse, most commonly hypertension (six patients; 7%) and colitis (five patients; 5%). Serious adverse events occurred in 53 (58%) of 92 patients, and were deemed related to treatment in 22 (24%) patients. The most common treatment-related serious adverse events were abdominal pain in patients with gastric or gastro-oesophageal junction adenocarcinoma (in three [7%] of 41 patients); asthenia and myocardial infarction in patients with non-small-cell lung cancer (two [7%] of 27 patients), and colitis in patients with urothelial carcinoma (two [8%] of 24 patients). Six (7%) of 92 patients discontinued treatment because of treatment-related adverse events, and one death (from pulmonary sepsis in a patient with gastric or gastro-oesophageal junction adenocarcinoma) was deemed related to treatment. The number of patients achieving an objective response was three (7%; 95% CI 1·5-19·9) of 41 in the gastric or gastro-oesophageal junction adenocarcinoma cohort, eight (30%; 13·8-50·2) of 27 in the non-small-cell lung cancer cohort, and three (13%, 2·7-32·4) in the urothelial carcinoma cohort.

INTERPRETATION

Ramucirumab in combination with pembrolizumab showed a manageable safety profile with favourable antitumour activity in patients with previously treated advanced gastric or gastro-oesophageal junction adenocarcinoma, non-small-cell lung cancer, and urothelial carcinoma. Our results contribute to the growing evidence that supports dual inhibition of the VEGF-VEGFR2 and PD-1-PD-L1 pathways. This combination could be further explored with or without chemotherapy, especially for patients with tumours for which single-agent checkpoint inhibitors have shown no additional benefit over chemotherapy.

FUNDING

Eli Lilly and Company, and Merck and Co.

A phase I dose escalation (DE) study of ERK inhibitor, LY3214996, in advanced (adv) cancer (CA) patients (pts)

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Background: LY3214996 is a selective and potent ERK1/2 inhibitor that has demonstrated tumor growth inhibition in several pre-clinical tumor models with BRAF, RAS, or MAP2K1 mutations. This is the first-in-human Phase 1 Study of LY3214996 in adv CA pts. Methods: The goals of this DE study were to determine a recommended Phase 2 dose (RP2D), safety, pharmacokinetic (PK), and preliminary efficacy of LY3214996 (NCT02857270; I8S-MC-JUAB; Eli Lilly & Co.). Pts with adv CA, ≥18 yrs of age, ECOG ≤1, and with adequate organ function were eligible. Pharmacodynamic (PD) biomarkers including pRSK were evaluated in blood and paired tumor tissue. The DE phase evaluated PO doses using the Bayesian model-based toxicity band method. Results: A total of 51 pts with median age of 62 yrs (range: 21-81) received at least 1 dose of LY3214996 with a median of 3 cycles (range: 1-12). Most pts had a mutation in RAS (N = 33) or BRAF (N = 16) and had a median of 4 prior lines of treatment. The DLTs observed in the study include grade (G) 3 cough and fatigue, G3 dehydration, increased creatinine (Cr), G3 increased CPK, G3 rash > 7 days, and 1 pt with renal failure. TRAEs to LY3214996 occurring in ≥10% of pts included nausea, vomiting, diarrhea, dermatitis acneiform, fatigue, pruritus, and blurred vision. LY3214996 exposures increased with dose. Tumor regression was observed in 7 pts with BRAF/non -BRAF mutant CA including 5 pts who failed prior IO/MAPK inhibitors. Four pts achieved stable disease (2 BRAF, 1 RAS and 1 CRAF mutation) that lasted > 4 mos. Up to 100% pRSK decrease from baseline in tumor was observed. Conclusions: LY3214996 had an acceptable safety profile, favorable PK, and potent tumor PD inhibition at RP2D. This supports further exploration of LY3214996 as monotherapy and in combination in CA pts with activating MAPK pathway alterations. Clinical trial information: NCT02857270.

Ramucirumab (Ram) and durvalumab (Durva) treatment of metastatic non-small cell lung cancer (NSCLC), gastric/gastroesophageal junction (G/GEJ) adenocarcinoma, and hepatocellular carcinoma (HCC) following progression on systemic treatment(s)

2528

Background: A Phase 1b study (NCT02572687) was conducted to examine the combined effects of Ram (anti VEGFR2) and Durva (anti PD-L1). Methods: Patients (pts) with previously-treated, advanced NSCLC (Cohort [CH] A), G/GEJ adenocarcinoma (CH B), HCC (CH C), ECOG PS 0-1, and no prior Ram or IO therapy, received Ram (10 mg/kg) + Durva (1125 mg) Q3W (CH A) or Ram (8 mg/kg) + Durva (750 mg) Q2W (CH B, C). Primary objective was to assess safety; efficacy was also examined. PD-L1 expression of tumor cells (TC) +/- immune cells (IC) in pretreatment tumor biopsies were assessed using SP263 immunohistochemistry. “High” PD-L1 is ≥25% TC for NSCLC and ≥25% TC or IC for G/GEJ, HCC. Results: CH A, B and C enrolled pts with ECOG PS 1 (%) of 43, 66, 68; and average of 2, 2, 1 prior regimens, respectively. The most common grade 3/4 treatment-emergent adverse events (AE) are hypertension (HTN) (14.3, 17.2, 17.9%), anemia (3.6, 24.1, 21.4%), and fatigue (10.7, 10.3, 10.7%). Grade 3/4 AEs of special interest ( > 5% total pts) for Ram: HTN, bleeding events (3.6, 10.3, 10.7%), Venous thromboembolic events (0, 10.3, 7.1%); for Durva: increase in lipase (10.7, 3.4, 10.6%) and AST (3.6, 3.4, 17.9 %). Data from CH B,C suggest a trend toward increased efficacy in pts with high PD-L1 expressing tumors. Conclusions: Ram + Durva generated no unexpected toxicities and demonstrated antitumor activity. Results in pts with high PD-L1 HCC and G/GEJ cancer warrant further evaluation. Clinical trial information: NCT02572687. [Table: see text]

Ramucirumab Plus Pembrolizumab in Patients with Previously Treated Advanced or Metastatic Biliary Tract Cancer: Nonrandomized, Open-Label, Phase I Trial (JVDF)

LESSONS LEARNED

Ramucirumab plus pembrolizumab revealed no unexpected safety findings in patients with advanced or metastatic biliary tract cancer, which is consistent with reports of other tumor cohorts within this phase Ia/b trial.Ramucirumab plus pembrolizumab did not demonstrate an improvement in overall survival when compared with historical controls in biomarker unselected, heavily pretreated patients with advanced or metastatic biliary tract cancer.Patients with programmed death-ligand 1 (PD-L1)-positive tumors had improved overall survival compared with patients with PD-L1-negative disease.

BACKGROUND

Few treatment options exist for patients with advanced biliary tract cancer (BTC) following progression on gemcitabine-cisplatin. Preclinical evidence suggests that simultaneous blockade of vascular endothelial growth factor receptor 2 (VEGFR-2) and programmed death 1 (PD-1) or programmed death-ligand 1 (PD-L1) enhances antitumor effects. We assessed the safety and efficacy of ramucirumab, an IgG1 VEGFR-2 antagonist, with pembrolizumab, an IgG4 PD-1 antagonist, in biomarker-unselected patients with previously treated advanced or metastatic BTC.

METHODS

Patients had previously treated advanced or metastatic adenocarcinoma of the gallbladder, intrahepatic and extrahepatic bile ducts, or ampulla of Vater. Ramucirumab 8 mg/kg was administered intravenously on days 1 and 8 with intravenous pembrolizumab 200 mg on day 1 every 3 weeks. The primary endpoint was safety and tolerability of the combination. Secondary endpoints included objective response rate (ORR), progression-free survival (PFS), and overall survival (OS).

RESULTS

Twenty-six patients were treated at 12 centers in five countries. Hypertension was the most common grade 3 treatment-related adverse event (TRAE), occurring in five patients. One patient experienced a grade 4 TRAE (neutropenia), and no treatment-related deaths occurred. Objective response rate was 4%. Median progression-free survival and overall survival were 1.6 months and 6.4 months, respectively.

CONCLUSION

Ramucirumab-pembrolizumab showed limited clinical activity with infrequent grade 3-4 TRAEs in patients with biomarker-unselected progressive BTC.

Ramucirumab Safety in East Asian Patients: A Meta-Analysis of Six Global, Randomized, Double-Blind, Placebo-Controlled, Phase III Clinical Trials

Purpose Several ramucirumab trials have reported a higher incidence of selected adverse events (AEs) in East Asian (EA) patients with cancer versus non-EA patients. A meta-analysis was conducted across six completed phase III trials to establish the safety parameters of ramucirumab in EA compared with non-EA patients. Materials and Methods Six global, randomized, double-blind, placebo-controlled, phase III registration trials investigating ramucirumab were assessed. Relative risks (RRs) and 95% CIs were calculated for selected all-grade and grade ≥ 3 AEs using fixed-effects and mixed-effects models. Ratio of RR and number needed to harm were calculated for AEs (all grade and grade ≥ 3) between EA and non-EA patients. Results Of 4,996 randomly assigned patients receiving ramucirumab or placebo, 802 (16.1%) were EA (ramucirumab, n = 411; placebo, n = 391) and 4,194 were non-EA (ramucirumab, n = 2,337; placebo, n = 1,857). Patient baseline characteristics were generally balanced between treatment arms in EA and non-EA patients, excluding sex and body weight. Grade ≥ 3 AEs possibly associated with ramucirumab, which were increased in EA versus non-EA patients, included neutropenia (42.1% v 25.5%, respectively) and proteinuria (3.9% v 0.6%, respectively). There was an increase in the RR of several grade ≥ 3 AEs, including hypertension and proteinuria, in ramucirumab-treated EA and non-EA patients compared with placebo. The ratio of RR revealed no significant differences between EA and non-EA patients for all-grade and grade ≥ 3 AEs. Conclusion Despite the enhanced propensity of selected AEs in EA patients relative to non-EA patients, there were no substantial differences in the RR for AEs possibly associated with ramucirumab in these phase III trials.

Interim safety and clinical activity in patients (pts) with locally advanced and unresectable or metastatic gastric or gastroesophageal junction (G/GEJ) adenocarcinoma from a multicohort phase I study of ramucirumab (R) plus durvalumab (D)

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Background: Angiogenesis and immunosuppression are hallmarks of tumor growth. This global phase 1 trial evaluates the combination of R (anti-VEGFR2) and D (anti-PD-L1) in pts with G/GEJ by simultaneously targeting these two processes. Methods: This ongoing, multi-cohort, phase 1a/b trial (NCT02572687) enrolled pts with confirmed G/GEJ adenocarcinoma with prior progression on 1 or 2 lines of systemic therapy, measurable disease, ECOG PS 0-1, and baseline tumor tissue. PD-L1 expression was assessed using the SP-263 IHC; MSI status was determined using PCR. Enrolled pts received R (8 mg/kg IV) and D (750 mg IV) every two weeks on a 28-day cycle. Primary objective was to assess safety and tolerability of R+D; preliminary efficacy was also examined. Results: As of 26-May-2017, 29 G/GEJ adenocarcinoma pts were treated. The median age was 55 y; 69% were male; 66% had ECOG PS of 1; 48% had PD-L1 ≥25% expression in tumor or immune cells, 3.5% were MSI-high; and 72% received study treatment as second line for advanced disease. Median duration of treatment was 2.5 mo for R and 3.0 mo for D. Treatment-emergent adverse events (TEAEs) occurred in 29 (100%) pts and 21 (72%) pts experienced grade 3/4 TEAEs, while treatment-related AEs (TRAE) occurred in 24 (83%) pts; none resulted in treatment discontinuation. Ten (35%) pts had grade 3 TRAEs, and no grade 4 or 5. All grade TRAEs occurring in ≥10% of pts were hypertension (34%), fatigue (31%), headache (24%), diarrhea (21%), pyrexia (10%) and decreased appetite (10%). Five pts (17%) reported a serious adverse event related to study treatment. Preliminary efficacy data (RECIST v1.1) showed 5 of 29 pts (17%) achieved a confirmed PR. Only 1 responding pt was MSI high. The overall response rate for pts with PD-L1 ≥25% was 36%. Median PFS was 2.6 mo (95% CI, 1.45 to 6.28). As of data cut-off, 6 pts (21%) remain on treatment. Conclusions: R+D generated no unexpected toxicity, and demonstrated antitumor activity in pts with previously treated advanced G/GEJ adenocarcinoma. Clinical trial information: NCT02572687.

Safety and antitumor activity of ramucirumab plus pembrolizumab in treatment naïve advanced gastric or gastroesophageal junction (G/GEJ) adenocarcinoma: Preliminary results from a multi-disease phase I study (JVDF)

101

Background: Preclinical evidence suggests simultaneous blockade of vascular endothelial growth factor receptor 2 (VEGFR-2) and programed cell death 1 protein (PD-1) induces synergistic antitumor effects. We assessed safety and preliminary efficacy of ramucirumab (anti-VEGFR-2) plus pembrolizumab (anti-PD-1) in patients (pts) with treatment naïve advanced G/GEJ adenocarcinoma. Methods: This ongoing, multi-cohort, phase 1a/b trial enrolled ECOG PS 0-1 pts with treatment naïve advanced G/GEJ adenocarcinoma with measurable disease and baseline tumor tissue. PD-L1 status was assessed by DAKO PD-L1 22C3 IHC pharmDx assay using the combined positive score with ≥1% being positive. Ramucirumab was administered at 8 mg/kg on Days 1 & 8 with pembrolizumab 200 mg on Day 1 q3W. Primary objective was safety and tolerability of study treatment; preliminary efficacy was examined. Results: As of 31-July-2017, 28 treatment naïve G/GEJ adenocarcinoma pts were treated. Median age was 63 y, 75% male, 57% had ECOG PS of 0, and 68% were PD-L1 positive. At data cutoff, 8 (28%) pts continued to receive study treatment. Median duration of follow-up was 8.1 mo (IQR 6-10). Median treatment duration was 4.3 mo (IQR 2-7). All grades treatment-related adverse events (TRAEs) occurred in 27 (96%) of patients; TRAEs in ≥15% of pts were fatigue (36%), hypertension (25%) and headache (18%). Seventeen (61%) pts experience grade 3 TRAEs, most commonly hypertension (14%), diarrhea (11%), and elevated alanine (7%) or aspartate (7%) aminotransferase. No grade 4-5 TRAEs occurred. An objective response was achieved by 7 (25%) pts, 6 positive and 1 negative for PD-L1. Disease control rate was 68%. Median time to response was 2.7 mo (95% CI 1.3-2.8) and median duration of response was 10 mo (95% CI 9.7-10.3). Median progression-free survival was 5.3 mo (95% CI 3.2-11). Median overall survival has not been reached. Conclusions: Ramucirumab plus pembrolizumab demonstrated encouraging antitumor activity in treatment naïve advanced G/GEJ adenocarcinoma with no grade 4 TRAE observed. Clinical trial information: NCT02443324.

EGFR Gene Copy Number by FISH May Predict Outcome of Necitumumab in Squamous Lung Carcinomas: Analysis from the SQUIRE Study

INTRODUCTION

Necitumumab is a monoclonal antibody targeting EGFR. In the SQUIRE trial, the addition of necitumumab to chemotherapy for squamous cell lung cancer significantly improved overall survival (OS) (hazard ratio [HR] = 0.84); in a post hoc analysis, EGFR copy number gain determined by fluorescence in situ hybridization (FISH) showed a trend toward improved OS (HR = 0.70) and progression-free survival (PFS) (HR = 0.71) with the addition of necitumumab. We present the analysis of granular EGFR FISH data from SQUIRE to examine the potential predictive role of high polysomy and gene amplification, as both were included in the FISH-positive category.

METHODS

Available specimens from SQUIRE underwent FISH analysis in a central laboratory, and each sample was evaluated by using the Colorado EGFR scoring criteria. The correlation of granular FISH parameters with clinical outcomes was assessed.

RESULTS

Samples were available for 557 of 1093 patients; 208 patients (37.3%) were FISH-positive, including 167 (30.0%) with high polysomy and 41 (7.4%) with gene amplification. In patients with high polysomy, the addition of necitumumab resulted in a statistically significant increase in PFS (6.08 versus 5.13 months [p = 0.044]) and nonstatistically significant increase in OS (12.6 versus 9.5 months [p = 0.133]); among patients with gene amplification, the addition of necitumumab did not significantly improve PFS (7.4 versus 5.6 months; [p = 0.334]) but did improve OS (14.8 versus 7.6 months; [p = 0.033]).

CONCLUSIONS

EGFR copy number gain by FISH might have a role as a predictive biomarker for necitumumab in squamous cell lung cancer. In our opinion, these data encourage further studies to prospectively evaluate this potential biomarker.

Ramucirumab (R) plus pembrolizumab (P) in treatment naive and previously treated advanced gastric or gastroesophageal junction (G/GEJ) adenocarcinoma: A multi-disease phase I study

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Background: Angiogenesis and immunosuppression are hallmarks of tumor growth. This is the first study to combine R (anti-VEGFR2) with P (anti-PD-1) to simultaneously target both processes in the tumor microenvironment. Methods: Ongoing, multi-cohort, phase 1a/b trial enrolled pts with G/GEJ adenocarcinoma, measurable disease, ECOG PS 0-1, previously treated (Cohorts A and B) or untreated (Cohort A2) for advanced disease. PD-L1 was positive (tumor proportion score [TPS] ≥1%) or negative (TPS < 1%) using the DAKO PD-L1 22C3 IHC pharmDx assay. R was administered at 8 mg/kg on Days 1&8 (Cohorts A and A2) or 10 mg/kg on Day 1 (Cohort B) with P 200 mg on Day 1 q3W. Primary objective- assess safety and tolerability of R+P; preliminary efficacy will be examined. Results: As of 21-Nov-2016, 41 previously treated G/GEJ pts were enrolled. Median age was 58 y, 76% male, 66% had ECOG PS of 1, 46% were PD-L1+, and 59% received study treatment as third or subsequent line. Median duration on therapy was 2.8 mo and 4.1 mo for A and B, respectively. Overall, 33 (80%) pts experienced a treatment-related AE (TRAE) and similar between cohorts A and B. Ten (24%) pts experienced grade 3-4 TRAEs, most commonly colitis (7%) and hypertension (7%). One treatment-related death occurred (pneumonitis and pulmonary sepsis). Responses occurred in 3 (7%) pts with 46% disease control rate (DCR). Progression-free and overall survival rates at 6 mo were 22.4 % (95% CI, 9.8-38.0) and 51.2% (95% CI, 33.9-66.1) respectively. Nine (22%) pts remain on treatment. Eighteen of 25 planned treatment naïve G/GEJ pts were enrolled. Median age was 70 yr, 83% male, 56% had ECOG PS of 0, and PD-L1 status is pending. Median duration on therapy was 2.1 mo. Twelve (67%) pts experienced a TRAE. Grade 3 TRAEs occurred in 5 (28%) pts (hypertension [n = 3], diarrhea, and acute kidney injury). No grade 4-5 events occurred. Preliminary efficacy data showed 3 (17%) pts responded with 50% DCR. Median PFS is immature and 89% of pts remain on treatment. Conclusions: R+P generated no new safety signals and demonstrated encouraging antitumor activity in treatment naïve and previously treatedadvanced G/GEJ adenocarcinoma. Clinical trial information: NCT02443324.

Enhancement of the adaptive signature design for learning and confirming in a single pivotal trial

Because of the complexity of cancer biology, often the target pathway is not well understood at the time that phase III trials are initiated. A 2-stage trial design was previously proposed for identifying a subgroup of interest in a learn stage, on the basis of 1 or more baseline biomarkers, and then subsequently confirming it in a confirmation stage. In this article, we discuss some practical aspects of this type of design and describe an enhancement to this approach that can be built into the study randomization to increase the robustness of the evaluation. Furthermore, we show via simulation studies how the proportion of patients allocated to the learn stage versus the confirm stage impacts the power and provide recommendations.

A multicohort phase I study of ramucirumab (R) plus pembrolizumab (P): Interim safety and clinical activity in patients with urothelial carcinoma

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Background: Hallmarks of tumor growth include immunosuppression and angiogenesis. This is the first study to combine R (anti-VEGFR2) with P (anti-PD-1) to simultaneously target both processes in the urothelial tumor microenvironment. Methods: This ongoing, multi-cohort, phase 1a/b trial (NCT02443324) enrolled patients (pts) with histologically confirmed transitional cell carcinoma of the urothelium (bladder, urethra, or renal pelvis) with prior progression on platinum-based systemic therapy, measurable disease, ECOG PS 0-1, and baseline tumor tissue. Eligible pts received R at 10 mg/kg on Day 1 given with P 200 mg on Day 1 q3W. PD-L1 was classified as positive (≥1%) or negative using the DAKO PD-L1 22C3 IHC pharmDx assay. Tumor response was assessed every 6 wks (RECIST v1.1). The primary objective was to assess safety and tolerability of adding R to P and preliminary efficacy will be assessed as a secondary objective. Results: As of 23-June-2016, 24 pts have been treated. The median age was 63 years, 58% were male, 50% had ECOG PS 0, 50% were PD-L1 positive and 67% received study treatment as third or subsequent regimen. Median duration of treatment was 2.14 mo and 2.37 mo for R and P, respectively. All grades treatment-related AEs (TRAE) occurred in 13 (54%) pts; TRAEs occurring in ≥10% of pts were fatigue (21%), nausea (17%), pyrexia (13%), elevated alanine aminotransferase (13%) and elevated aspartate aminotransferase (13%). Three (13%) pts had grade 3 TRAEs (hypertension, colitis, pulmonary embolism; n=1 each). No treatment-related grade 4 or 5 events occurred. Preliminary efficacy data showed two (8%) PD-L1 positive pts had confirmed partial response, 10 (42%) pts had stable disease, and 10 (42%) had progressive disease as their best response. Two (8%) pts were not evaluable for response at the time of analysis. Median duration of response has not been reached (>2.92 mo). Median PFS was 1.87 mo (95% CI, 1.28 to 3.38). Five (21%) pts remain on treatment. Conclusions: R plus P generated no new safety signals and demonstrated antitumor activity in pts with previously treated advanced urothelial carcinoma. Clinical trial information: NCT02443324.

Interim safety and clinical activity in patients (pts) with advanced gastric or gastroesophageal junction (G/GEJ) adenocarcinoma from a multicohort phase 1 study of ramucirumab (R) plus pembrolizumab (P)

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Background: Angiogenesis and immunosuppression are hallmarks of tumor growth. This is the first study to combine R (anti-VEGFR2) with P (anti-PD-1) to simultaneously target both processes in the tumor microenvironment. Methods: This ongoing, multi-cohort, phase 1a/b trial (NCT02443324) enrolled pts with confirmed G/GEJ adenocarcinoma with prior progression on systemic therapy, measurable disease, ECOG PS 0-1, and baseline tumor tissue. PD-L1 was classified as positive (≥1%) or negative using the DAKO PD-L1 22C3 IHC pharmDx assay. Two dosing regimens were evaluated, Cohort A (R 8 mg/kg on Days 1&8) and Cohort B (R 10 mg/kg on Day 1), given with P 200 mg on Day 1 q3W. The primary objective was to assess safety and tolerability of adding R to P; preliminary efficacy will be examined. Results: As of 23-Jun-2016, 40 G/GEJ pts have been enrolled (Cohort A: n=23; Cohort B: n=17). First pt treated in Cohorts A and B were on 29-Feb-2016 and 26-Oct-2015, respectively. The median age was 59 y, 75% were male, 65% had ECOG PS of 1, 48% were PD-L1 positive, and 70% received study treatment as third or subsequent regimen. Median duration of treatment was 2.1 mo and 4.1 mo for Cohort A and B, respectively. All grades treatment-related AEs (TRAE) occurred in 31 (78%) pts and similar between cohorts; TRAEs in ≥10% of pts were fatigue (30%), infusion related reaction (12.5%), decreased appetite (12.5%), pruritus (10%), maculopapular rash (10%), and hypertension (10%). Ten (25%) pts had grade 3-4 TRAEs, most commonly colitis (7.5%) and hypertension (7.5%). One treatment-related death occurred (pneumocystis pneumonia and pulmonary sepsis). Preliminary efficacy data showed 3 of 40 (7.5%) pts (PD-L1 negative, n=1; PD-L1 positive, n=2) have responded (1 confirmed and 2 unconfirmed PR) to treatment with a 45% disease control rate. Median PFS was 2.10 mo (95% CI, 1.18 to 4.04) and 2.60 mo (1.38, NR) for Cohorts A and B, respectively. Fifteen (37.5%) pts, including all responders, remain on treatment. Conclusions: R+P generated no new safety signals and demonstrated antitumor activity in pts with previously treated advanced G/GEJ adenocarcinoma. Clinical trial information: NCT02443324.

Associations of serotonin receptor gene HTR3A, HTR3B, and HTR3A haplotypes with bipolar disorder in Chinese patients

Single nucleotide polymorphisms (SNPs) in HTR3A and HTR3B have been reported to be associated with bipolar disorder in European and Japanese populations. We explored the roles of 21 tag SNPs in HTR3A and HTR3B in susceptibility to bipolar disorder in a Chinese cohort. Twenty-one Tag SNPs were genotyped in a study consisting of 130 patients with bipolar disorder, who visited Shandong Mental Health Center between June 2013 and May 2014, and 109 healthy individuals as controls. All of the tag SNPs were genotyped using Sequenom MassArray matrix-assisted laser desorption/ionization time of flight spectrometry. Plink 1.07, Haploview 4.2, and SPSS 20.0 were used for the analysis of the genotypes and the associations of the haplotypes with bipolar disorder. Association analyses of tag SNPs detected significant associations with the A allele in HTR3A rs1176719 (P = 0.030) and the C allele in HTR3A rs1176713 (P = 0.048). Haplotype-based association analyses indicated a statistically significant (P = 0.035) five-SNP haplotype (rs1062613:C, rs11604247:C, rs1176722:G, rs2276302:A, rs1176719:G) of linkage disequilibrium in block 3. Analysis of our small Chinese sample revealed a significant association of HTR3A with bipolar disorder, but yielded no evidence of an association between HTR3B and bipolar disorder. Furthermore, evidence for an association was found for a haplotype of HTR3A. Studies with larger Chinese samples are needed to verify our findings.

The level of residual dispersion variation and the power of differential expression tests for RNA-Seq data

RNA-Sequencing (RNA-Seq) has been widely adopted for quantifying gene expression changes in comparative transcriptome analysis. For detecting differentially expressed genes, a variety of statistical methods based on the negative binomial (NB) distribution have been proposed. These methods differ in the ways they handle the NB nuisance parameters (i.e., the dispersion parameters associated with each gene) to save power, such as by using a dispersion model to exploit an apparent relationship between the dispersion parameter and the NB mean. Presumably, dispersion models with fewer parameters will result in greater power if the models are correct, but will produce misleading conclusions if not. This paper investigates this power and robustness trade-off by assessing rates of identifying true differential expression using the various methods under realistic assumptions about NB dispersion parameters. Our results indicate that the relative performances of the different methods are closely related to the level of dispersion variation unexplained by the dispersion model. We propose a simple statistic to quantify the level of residual dispersion variation from a fitted dispersion model and show that the magnitude of this statistic gives hints about whether and how much we can gain statistical power by a dispersion-modeling approach.

Goodness-of-fit tests and model diagnostics for negative binomial regression of RNA sequencing data

This work is about assessing model adequacy for negative binomial (NB) regression, particularly (1) assessing the adequacy of the NB assumption, and (2) assessing the appropriateness of models for NB dispersion parameters. Tools for the first are appropriate for NB regression generally; those for the second are primarily intended for RNA sequencing (RNA-Seq) data analysis. The typically small number of biological samples and large number of genes in RNA-Seq analysis motivate us to address the trade-offs between robustness and statistical power using NB regression models. One widely-used power-saving strategy, for example, is to assume some commonalities of NB dispersion parameters across genes via simple models relating them to mean expression rates, and many such models have been proposed. As RNA-Seq analysis is becoming ever more popular, it is appropriate to make more thorough investigations into power and robustness of the resulting methods, and into practical tools for model assessment. In this article, we propose simulation-based statistical tests and diagnostic graphics to address model adequacy. We provide simulated and real data examples to illustrate that our proposed methods are effective for detecting the misspecification of the NB mean-variance relationship as well as judging the adequacy of fit of several NB dispersion models.

Length bias correction in gene ontology enrichment analysis using logistic regression

When assessing differential gene expression from RNA sequencing data, commonly used statistical tests tend to have greater power to detect differential expression of genes encoding longer transcripts. This phenomenon, called “length bias”, will influence subsequent analyses such as Gene Ontology enrichment analysis. In the presence of length bias, Gene Ontology categories that include longer genes are more likely to be identified as enriched. These categories, however, are not necessarily biologically more relevant. We show that one can effectively adjust for length bias in Gene Ontology analysis by including transcript length as a covariate in a logistic regression model. The logistic regression model makes the statistical issue underlying length bias more transparent: transcript length becomes a confounding factor when it correlates with both the Gene Ontology membership and the significance of the differential expression test. The inclusion of the transcript length as a covariate allows one to investigate the direct correlation between the Gene Ontology membership and the significance of testing differential expression, conditional on the transcript length. We present both real and simulated data examples to show that the logistic regression approach is simple, effective, and flexible.

Power of association tests in the presence of multiple causal variants

We show that the statistical power of a single single-nucleotide polymorphism (SNP) score test for genetic association reflects the cumulative effect of all causal SNPs that are correlated with the test SNP. Statistical significance of a score test can sometimes be explained by the collective effect of weak correlations between the test SNP and multiple causal SNPs. In a finite population, weak but significant correlations between the test SNP and the causal SNPs can arise by chance alone. As a consequence, when a single-SNP score test shows significance, the causal SNPs contributing to the power of the test are not necessarily located near the test SNP, nor do they have to be in linkage disequilibrium with the test SNP. These findings are confirmed with the Genetic Analysis Workshop 17 mini-exome data. The findings of this study highlight the often overlooked importance of long-range and weak linkage disequilibrium in genetic association studies.

[Studies of the determination of glycyrrhizin acid kali salt by HPLC and the pharmacokinetics]

To find a practive and quick method determining GK concentration in blood by HPLC and to study its pharmacokinetics. GK from Glycyrrhiza uralensis Fisch was extracted and purified. GK were administered to mice by i.v. and ig. The Concentration of GK in blood at expected time was determined by HPLC. The data was dealed with by 3 P 87 programe. The concentration-time curve of i.v. 0.1% GK 40 mg/kg is in accordance with tow-compartment model. t1/2 alpha = 5.128 min, t1/2 beta = 51.196 min, AUC = 7477.642 (micrograms/ml).min, Cl(s) = 0.0956 microgram/min(microgram/ml). The c-t curve of ig. 2.2% GK 500 mg/kg is in accordance with tow compartment model, t1/2 alpha = 15.97 min, t1/2 beta = 200.05 min, AUC = 2453.96(micrograms/ml).min, Cl(s) = 3.642 micrograms/min(micrograms/ml). HPLC is a quick and practive method to determin the concentration of GK in blood.

[Study of the inclusion compound of rutin with beta-cyclodextrin]

In order to improve the solubility of Rutin in aqueous solution and the stability, the inclusion compound of Rutin with beta-CD was manufacted by saturated aqueous solution method. The formation of the inclusion compound was confirmed by IR spectroscopy and differential scauning calorimetry. The content of Rutin in inclusion compound was determined by UV. The results indicated that the inclusion compound of Rutin with beta-CD was formed. Quantitative analysis demmonstrated that the molecular ratio of Rutin to beta-CD in the complex was 1:1 with the inclusion constant of 283.79 L/mol at 30 degrees C. The dissolubility of Rutin in water has added to 643.19 mg/L (20 degrees C).