Tuning LSPR of Thermal Spike-Induced Shape-Engineered Au Nanoparticles Embedded in Si3N4 Thin-Film Matrix for SERS Applications

While gold nanoparticles (Au NPs) are widely used as surface-enhanced Raman spectroscopy (SERS) substrates, their agglomeration and dynamic movement under laser irradiation result in the major drawback in SERS applications, viz., the repeatability of SERS signals. We tune the optical and structural properties of size- and shape-modified Au NPs embedded in a thin silicon nitride (Si3N4) matrix by intense electronic excitation with swift heavy ion (SHI) irradiation with the aim of overcoming this classical SERS disadvantage. We demonstrate the shape evolution of a single layer of Au NPs inserted between amorphous Si3N4 thin films under fluences of 120 MeV Au9+ ions ranging between 1 × 1011 and 1 × 1013 ions cm-2. This shape modification results in the gradual blue shift of the localized surface plasmon resonance (LSPR) dip until 1 × 1012 ions/cm2 and then a sudden diminishment at 1 × 1013 ions/cm2. Finite domain time difference (FDTD) simulations further justify our experimental optical spectra. The dynamical NP aggregation and dissolution, in addition to NP elongation and deformation at different fluences, are noted from 2D grazing incidence small-angle X-ray scattering (GISAXS) profiles, as well as cross-sectional transmission electron microscopy (X-TEM). The systematic shape evolution of metal NPs embedded in the insulating matrix is shown to be due to thermal spike-induced localized melting and a localized pressure hike upon SHI irradiation. Utilizing this specific control over the characteristics of Au NPs, viz., shape, size, interparticle gap, and corresponding optical response via SHI irradiation, we demonstrate their applications as very stable SERS substrates, where the separation between NPs and analyte does not alter under laser illumination. Thus, these irradiated SERS active substrates with controlled NP size and gap provide the optimal conditions for creating localized electromagnetic hotspots that amplify the SERS signals, which do not alter with time or laser exposure. We found that the film irradiated with 1 × 1011 exhibits the highest SERS intensity due to its optimal NP size distribution and shape. Thus, not only our study provides a SERS substrate for stable and repeatable signals but also the understanding depicted here opens new research avenues in designing SERS substrates, photovoltaics, optoelectronic devices, etc. with ion beam irradiation.

Predictors of recurrence following laparoscopic minor hepatectomy for hepatocellular carcinoma in the UK

AIMS

Minor hepatectomy, which is increasingly carried out laparoscopically (LLR), is a cornerstone of curative treatment for hepatocellular carcinoma (HCC). The majority of relevant publications however originate from regions with endemic viral hepatitis. Although the incidence of HCC in the UK is increasing, little is known about outcomes following LLR.

METHODS

Consecutive patients undergoing minor (involving ≤2 segments) LLR or open resection (OLR) at our institute between 2014 and 2021 were compared. Selection from a plethora of factors potentially impacting on overall (OS) and disease free survival (DFS) was optimised with Lasso regression. To enable analysis of patients having repeat resection, multivariate frailty modelling was utilised to calculate hazard ratios (HR).

RESULTS

The analysis of 111 liver resections included 55 LLR and 56 OLR. LLR was associated with a shorter hospital stay (5 ± 2 vs. 7 ± 2 days; p < 0.001) and a lower comprehensive complication index (4.43 vs. 9.96; p = 0.006). Mean OS (52.3 ± 2.3 vs. 49.9 ± 3.0 months) and DFS (33.9 ± 3.4 vs. 36.5 ± 3.6 months; p = 0.59) were comparable between LLR and OLR, respectively (median not reached). Presence of mixed cholangiocarcinoma/HCC, satellite lesions and AFP level predicted OS and DFS. In addition tumour size was predictive of DFS.

CONCLUSIONS

In the studied population minor LLR was associated with shorter hospital stay and fewer complications while offering non-inferior long-term outcomes. A number of predictors for disease free survival have been elucidated that may aid in identifying patients with a high risk of disease recurrence and need for further treatment.

Revealing the Formation Mechanism and Optimizing the Synthesis Conditions of Layered Double Hydroxides for the Oxygen Evolution Reaction

Layered double hydroxides (LDHs), whose formation is strongly related to OH^- concentration, have attracted significant interest in various fields. However, the effect of the real-time change of OH^- concentration on LDHs' formation has not been fully explored due to the unsuitability of the existing synthesis methods for in situ characterization. Here, the deliberately designed combination of NH₃ gas diffusion and in situ pH measurement provides a solution to the above problem. The obtained results revealed the formation mechanism and also guided us to synthesize a library of LDHs with the desired attributes in water at room temperature without using any additives. After evaluating their oxygen evolution reaction performance, we found that FeNi-LDH with a Fe/Ni ratio of 25/75 exhibits one of the best performances so far reported.

Single-atom alloy catalysts designed by first-principles calculations and artificial intelligence

Single-atom-alloy catalysts (SAACs) have recently become a frontier in catalysis research. Simultaneous optimization of reactants' facile dissociation and a balanced strength of intermediates' binding make them highly efficient catalysts for several industrially important reactions. However, discovery of new SAACs is hindered by lack of fast yet reliable prediction of catalytic properties of the large number of candidates. We address this problem by applying a compressed-sensing data-analytics approach parameterized with density-functional inputs. Besides consistently predicting efficiency of the experimentally studied SAACs, we identify more than 200 yet unreported promising candidates. Some of these candidates are more stable and efficient than the reported ones. We have also introduced a novel approach to a qualitative analysis of complex symbolic regression models based on the data-mining method subgroup discovery. Our study demonstrates the importance of data analytics for avoiding bias in catalysis design, and provides a recipe for finding best SAACs for various applications.

Synergistic Effects of Ternary PdO-CeO2-OMS-2 Catalyst Afford High Catalytic Performance and Stability in the Reduction of NO with CO

We developed a robust ternary PdO-CeO₂-OMS-2 catalyst with excellent catalytic performance in the selective reduction of NO with CO using a strategy based on combining components that synergistically interact leading to an effective abatement of these toxic gases. The catalyst affords 100% selectivity to N₂ at the nearly full conversion of NO and CO at 250 °C, high stability in the presence of H₂O, and a remarkable SO₂ tolerance. To unravel the origin of the excellent catalytic performance, the structural and chemical properties of the PdO-CeO₂-OMS-2 nanocomposite were analyzed in the as-prepared and used state of the catalyst, employing a series of pertinent characterization methods and specific catalytic tests. The experimental as well as theoretical results, based on density-functional theory calculations suggest that CO and NO follow different reaction pathways, CO is preferentially adsorbed and oxidized at Pd sites (Pd^II and Pd⁰), while NO decomposes on the ceria surface. Lattice oxygen vacancies at the interfacial perimeter of PdO-CeO₂ and PdO-OMS-2, and the diffusion of oxygen and oxygen vacancies are proposed to play a critical role in this multicenter reaction system.

First-in-human study of LY3039478, an oral Notch signaling inhibitor in advanced or metastatic cancer

Background

Deregulated Notch signaling due to mutation or overexpression of ligands and/or receptors is implicated in various human malignancies. γ-Secretase inhibitors inhibit Notch signaling by preventing cleavage of transmembrane domain of Notch protein. LY3039478 is a novel, potent Notch inhibitor decreases Notch signaling and its downstream biologic effects. In this first-in-human study, we report the safety, pharmacokinetic (PK) profile, pharmacodynamic effects, and antitumor activity of LY3039478 in patients with advanced or metastatic cancer.

Methods

This phase I, open-label, multicenter, nonrandomized, and dose-escalation phase study determined and confirmed the recommended phase II dose of LY3039478 (oral dose: 2.5-100 mg, thrice weekly (TIW) on a 28-day cycle). The primary objectives are to determine (part A) and confirm (part B) a recommended phase II dose that may be safely administered to patients with advanced or metastatic cancer, and secondary objectives include evaluation of safety, tolerability, PK parameters, and preliminary antitumor activity of LY3039478.

Results

A total of 110 patients were treated with LY3039478 monotherapy between 31 October 2012 and 15 July 2016. Dose-limiting toxicities were thrombocytopenia, colitis, and nausea. Most adverse events were gastrointestinal. The recommended phase II dose was 50 mg TIW, because of its better tolerability compared with 75 mg. The PKs of LY3039478 appeared dose proportional. Pharmacodynamic data indicate an ∼80% inhibition of plasma Aβ, and >50% inhibition of Notch-regulated genes hairy and enhancer of split-1, cyclin D1, and Notch-regulated ankyrin repeat at 45-100-mg dose. Clinical activity (tumor necrosis, metabolic response, or tumor shrinkage) was observed in patients with breast cancer, leiomyosarcoma, and adenoid cystic carcinoma.

Conclusion

Potent inhibition of Notch signaling by LY3039478 was well tolerated at doses associated with target engagement, and demonstrated evidence of clinical activity in heavily pretreated patients. Further investigation with LY3039478 as monotherapy and in combination with targeted agent or chemotherapy is ongoing.

Clinicaltrials.gov ID

NCT01695005.

Phase III randomized study of second line ADI-PEG 20 plus best supportive care versus placebo plus best supportive care in patients with advanced hepatocellular carcinoma

Background

Arginine depletion is a putative target in hepatocellular carcinoma (HCC). HCC often lacks argininosuccinate synthetase, a citrulline to arginine-repleting enzyme. ADI-PEG 20 is a cloned arginine degrading enzyme-arginine deiminase-conjugated with polyethylene glycol. The goal of this study was to evaluate this agent as a potential novel therapeutic for HCC after first line systemic therapy.

Methods and patients

Patients with histologically proven advanced HCC and Child-Pugh up to B7 with prior systemic therapy, were randomized 2 : 1 to ADI-PEG 20 18 mg/m2 versus placebo intramuscular injection weekly. The primary end point was overall survival (OS), with 93% power to detect a 4-5.6 months increase in median OS (one-sided α = 0.025). Secondary end points included progression-free survival, safety, and arginine correlatives.

Results

A total of 635 patients were enrolled: median age 61, 82% male, 60% Asian, 52% hepatitis B, 26% hepatitis C, 76% stage IV, 91% Child-Pugh A, 70% progressed on sorafenib and 16% were intolerant. Median OS was 7.8 months for ADI-PEG 20 versus 7.4 for placebo (P = 0.88, HR = 1.02) and median progression-free survival 2.6 months versus 2.6 (P = 0.07, HR = 1.17). Grade 3 fatigue and decreased appetite occurred in <5% of patients. Two patients on ADI-PEG 20 had ≥grade 3 anaphylactic reaction. Death rate within 30 days of end of treatment was 15.2% on ADI-PEG 20 versus 10.4% on placebo, none related to therapy. Post hoc analyses of arginine assessment at 4, 8, 12 and 16 weeks, demonstrated a trend of improved OS for those with more prolonged arginine depletion.

Conclusion

ADI-PEG 20 monotherapy did not demonstrate an OS benefit in second line setting for HCC. It was well tolerated. Strategies to enhance prolonged arginine depletion and synergize the effect of ADI-PEG 20 are underway.

Clinical Trial number

www.clinicaltrials.gov (NCT 01287585).

Manipulating Localized Vibrations of Interstitial Te for Ultra-High Thermoelectric Efficiency in p-Type Cu-In-Te Systems

Thermoelectric materials are of imperative need on account of the worldwide energy crisis. However, their efficiency is limited by the interplay of high electrical and lower thermal conductivities, that is, the figure of merit (ZT). Owing to their unique crystal structures, Cu-In-Te-based chalcogenides are suitable for both and thus have attracted much attention recently as potential thermoelectrics. Here we explore a newly developed Cu-In-Te derivative compound Cu_3.52In_4.16Te₈. With a proper adjustment of Cu₂Te doping, this material shows an ultralow lattice thermal conductivity (κ_L) (0.3 WK^-1m^-1) and, consequently, a figure of merit (ZT) as high as 1.65(±0.15) at 815 K: the highest value reported for p-type Cu-In-Te to date. The reduction in κ_L is directly related to the alteration of local symmetry around the interstitial Te, resulting in an effectively optimized phonon transport through localized "rattling" of the same. Although the Hall carrier concentration reduces upon Cu₂Te addition due to the unpinning of the Fermi level (E_Fermi) toward the conduction band minimum, the power factor remains stable. The knowledge depicted here not only demonstrates the potential of Cu_3.52In_4.16Te₈-based alloys as a promising TE, but also provides guidelines for developing further high-performance thermoelectric materials by enhancing the electronic conductivity.

Evidence of local structural influence on the shape driven magnetic anisotropy in electronically excited Ni nanoparticles embedded in SiO2 matrix

The reliance of modern electronic era on ultrafast data recording has made the search for novel tools to tune nano-scale magnetic-anisotropy (MA) never-ending. We demonstrate a strong correlation between the spin-spin interactions, local atomic structure and the MA of Ni nanoparticles (NPs) embedded inside SiO₂ matrix under swift heavy ion (SHI) irradiation. In contrast to traditional understandings, MA in Ni NPs along with their aspect ratio, first increases upto 5 × 10¹³ ions/cm² SHI fluence (5e13) and gets reduced at highest fluence. Using angle dependent Extented-Xray-Absorption-Fine-Structure (EXAFS) and ab initio molecular dynamics (MD) simulations, we show that the anisotropy induced in local atomic structure upon irradiation is dependent on atomic spin-spin interactions, which gets reduced at highest fluence. The chosen model cluster (Ni₃₈) used in our MD simulations is duly validated by comparing the pair-correlation-function of the structure with the EXAFS-Fourier-Transform. The lattice temperatures for the films irradiated at different fluences, as calculated from thermal-spike-model, are used for the respective MD runs. We conclude that the enhanced disorder in both the local atomic environment and spin alignment destroys the MA at the highest fluence in SHI irradiated Ni NPs. The findings therefore provide rich conceptual insights for designing magnetic devices using SHI-induced phenomena.

Effect of Obesity on Hemoglobin Concentration

Obesity is a disorder of body weight regulatory systems characterized by an accumulation of excess body fat. World Health Organization recommended that 66% of deaths now occur in developing countries and recognizes obesity as a leading risk factor. Obesity is associated with chronic, low grade, systemic inflammation. The inflammatory state play a causal role in the development of insulin resistance, type 2 diabetes and the metabolic syndrome. This descriptive type of cross sectional study will design to evaluate the relation between obesity with hemoglobin concentration. One hundred obese and 100 normal weight persons from both sexes, aged between 25 to 60 years will be selected from Mymensingh Medical College, Mymensingh and locality from July 2014 to January 2016. Data are collected through a simple questionnaire after informed consent taken. The result was calculated and analyzed by using SPSS (statistical package for social science, version 11.5). Statistical significance of difference between two groups were evaluated by unpaired Student's 't' test. Data were expressed as Mean±SE. P value less than 0.05 was taken as the level of significance. Anthropometric measurements such as height and weight were taken in meter and kilogram respectively. Pulse, systolic and diastolic blood pressure was measured by aneroid sphygmomanometer (ALPK2, Japan), laboratory analysis of hemoglobin was done by Cyanmethemoglobin Method. In this study we found that hemoglobin concentration is significantly increased in both male and female obese persons.

Triggering of spin-flipping-modulated exchange bias in FeCo nanoparticles by electronic excitation

The exchange coupling between ferromagnetic (FM)-antiferromagnetic (AF) interfaces is a key element of modern spintronic devices. We here introduce a new way of triggering exchange bias (EB) in swift heavy ion (SHI) irradiated FeCo-SiO2 films, which is a manifestation of spin-flipping at high irradiation fluence. The elongation of FeCo nanoparticles (NPs) in SiO2 matrix gives rise to perpendicular magnetic anisotropy at intermediate fluence. However, a clear shift in hysteresis loop is evident at the highest fluence. This reveals the existence of an AF exchange pinning domain in the NPs, which is identified not to be oxide shell from XANES analysis. Thermal spike calculations along with first-principles based simulations under the framework of density functional theory (DFT) demonstrate that spin flipping of 3d valence electrons is responsible for formation of these AF domains inside the FM NPs. EXAFS experiments at Fe and Co K-edges further unravel that spin-flipping in highest fluence irradiated film results in reduced bond lengths. The results highlight the possibility of miniaturization of magnetic storage devices by using irradiated NPs instead of conventionally used FM-AF multilayers.

Abstract P4-14-26: Phase I expansion of S-222611, a reversible inhibitor of EGFR and HER2, in advanced solid tumors, including HER2-positive breast cancer patients with brain metastases

BACKGROUND

S-222611 is an oral, reversible ErbB tyrosine kinase inhibitor of EGFR and HER2 with potent pre-clinical activity. MTD was not reached during the dose-escalation phase, (maximum dose 1600 mg QD). PK and efficacy data supported a daily dose of 800 mg. An expansion cohort of patients has been treated to further explore safety and efficacy.

METHODS

Subjects with advanced solid tumors expressing EGFR and/or overexpressing HER2 were enrolled. S-222611 800 mg daily was administered until disease progression or unacceptable toxicity.

RESULTS

76 patients were included in this phase 1 expansion cohort with a variety of tumor types. Dose reduction was required because of adverse events in 15 patients; the most frequent of which being diarrhea and elevated bilirubin. Two patients discontinued treatment due to drug- related adverse events. Of the 25 patients with HER2-positive metastatic breast cancer (MBC), 4 partial responses were observed, and prolonged stable disease (≥ 6 months) was observed in 3 additional patients. These 25 patients had received prior HER2-directed therapy as shown in Table 1.

Table 1. Prior therapies received by patients with HER2-positive MBCPrior therapyn (%)Trastuzumab22 (88)T-DM13 (12)Lapatinib16 (64)Chemotherapy23 (92)

Six of these patients had brain metastases, in whom 1 intracranial response and 2 prolonged stable disease (≥ 6 months) were observed (Table 2).

Table 2. HER2-positive MBC patients with brain metastases - best overall response to S-222611Pts #HER2 IHCBrain metastasesBest overall response (RECIST 1.1)Patient 13+Target lesionPRPatient 23+Target lesionSD (≥12 M)Patient 33+Target lesionSD (6.0 M)Patient 43+Non-target lesionSD (4.7 M)Patient 53+Non-target lesionSD (3.3 M)Patient 63+Non-target lesionNE

The patient showing intracranial response was previously treated with lapatinib and capecitabine after diagnosis of BM.

CONCLUSIONS

S-222611 was well tolerated at a dose of 800 mg once daily. Anti-tumour activity, including shrinkage of brain metastases, was evident in a heavily pre-treated population of patients with HER2-positive breast cancer.

Citation Format: Baird RD, Arkenau H-T, Deva S, Cresti N, Garcia-Corbacho J, Hogarth L, Frenkel E, Kawaguchi K, Arimura A, Donaldson K, Posner J, Sarker D, Jodrell D, Plummer R, Spicer J, Italiano A. Phase I expansion of S-222611, a reversible inhibitor of EGFR and HER2, in advanced solid tumors, including HER2-positive breast cancer patients with brain metastases. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-14-26.

Unraveling The Origin of Enhanced Field Emission from Irradiated FeCo-SiO2 Nanocomposites: A Combined Experimental and First-Principles Based Study

This work is driven by the vision of engineering planar field emitters with ferromagnetic metal-insulator nanocomposite thin films, using swift heavy ion (SHI) irradiation method. FeCo nanoparticles inside SiO2 matrix, when subjected to SHI get elongated. Using this, we demonstrate here a planar field emitter with maximum current density of 550 μA/cm(2) at an applied field of 15 V/μm. The film, irradiated with 5 × 10(13) ions/cm(2) fluence (5e13) of 120 MeV Au(9+) ions, shows very high electron emitting quantum efficiency in comparison to its unirradiated counterpart. Surface enhanced Raman spectroscopy analysis of unirradiated and 5e13 films further confirms that the field emission (FE) enhancement is not only due to surface protrusions but also depends on the properties of entire matrix. We find experimental evidence of enhanced valence band density of states (VB DOS) for 5e13 film from XPS, which is verified in the electronic structure of a model FeCo cluster from first-principles based calculations combining density functional theory (DFT) and molecular dynamics (MD) simulations. The MD temperature is selected from the lattice temperature profile inside nanoparticles as deduced from thermal spike model. Increasing the irradiation fluence beyond 5e13, results in reduced VB DOS and melting of surface protrusions, thus causing reduction of FE current density. We finally conclude from theoretical analysis that change in fluence alters the co-ordination chemistry followed by the charge distribution and spin alignment, which influence the VB DOS and concurrent FE as evident from our experiment.

Phase 1 dose-escalation study of S-222611, an oral reversible dual tyrosine kinase inhibitor of EGFR and HER2, in patients with solid tumours

BACKGROUND

S-222611 is a reversible inhibitor of EGFR, HER2 and HER4 with preclinical activity in models expressing these proteins. We have performed a Phase 1 study to determine safety, maximum tolerated dose (MTD), pharmacokinetic profile (PK) and efficacy in patients with solid tumours expressing EGFR or HER2.

PATIENTS AND METHODS

Subjects had advanced tumours not suitable for standard treatment, expressing EGFR or HER2, and/or with amplified HER2. Daily oral doses of S-222611 were escalated from 100mg to 1600 mg. Full plasma concentration profiles for drug and metabolites were obtained.

RESULTS

33 patients received S-222611. It was well tolerated, and the most common toxicities, almost all mild (grade 1 or 2), were diarrhoea, fatigue, rash and nausea. Only two dose-limiting toxicities occurred (diarrhoea and rash), which resolved on interruption. MTD was not reached. Plasma exposure increased with dose up to 800 mg, exceeding levels eliciting pre-clinical responses. The plasma terminal half-life was more than 24h, supporting once daily dosing. Responses were seen over a wide range of doses in oesophageal, breast and renal tumours, including a complete clinical response in a patient with HER2-positive breast carcinoma previously treated with lapatinib and trastuzumab. Four patients have remained on treatment for more than 12 months. Downregulation of pHER3 was seen in paired tumour biopsies from a responding patient.

CONCLUSIONS

Continuous daily oral S-222611 is well tolerated, modulates oncogenic signalling, and has significant antitumour activity. The recommended Phase 2 dose, based on PK and efficacy, is 800 mg/day.

Spectral weight shift in the valence band density of states and concurrent increase in field emission by hydrogenation of FeCo–SiO2 nanocomposites

Roughened surface and enhanced valence electronic states of hydrogen plasma treated FeCo–SiO₂ nanogranular films has made it an efficient field emitter in comparison to its as-grown and furnace annealed counterparts.

Effect of nutrition education on exclusive breastfeeding for nutritional outcome of low birth weight babies

BACKGROUND/OBJECTIVES

Low birth weight (LBW), defined as the body weight at birth of less than 2500 g, is a major public health problem in Bangladesh, where 37% of the babies are born with LBW. The objective of this study is to see the impact of nutrition education on growth of LBW babies with early initiation and exclusive breastfeeding compared to control group.

SUBJECTS/METHODS

A total of 184 LBW babies and their mothers who attended the Maternal Care and Health Training Institute and Dhaka Medical College Hospital were randomly allocated to either intervention or control group. Enrollment of the study population started in May 2008 and was completed in October 2008. Nutrition education was given to mothers twice weekly for 2 months, on initiation of breastfeeding within 1 h, exclusive breastfeeding and increasing their dietary intake. Nutritional status of LBW babies was assessed for length and weight every 2 weeks. Data were analyzed using SPSS/Window's version 12. Comparison of mean of data was done using standard Student's t-test.

RESULTS

Mean initial body weight and length of LBW babies were similar in both groups (2261±198 g vs 2241±244 g, P=0.535 and 43.0±1.3 cm vs 43.0±1.7 cm, P=0.77). Body weight and length of the LBW babies after 2 months increased significantly (3620±229 g vs 3315±301 g, P<0.001 and 50.2±1.3 cm vs 48.7±1.6 cm, P<0.001). It was found that the intervention group suffered less from respiratory illness compared with the control group (39% vs 66%, P<0.001). The rate of early initiation of breastfeeding was also significantly higher with nutrition intervention (59.8% vs 37.2%, P<0.001). Exclusive breastfeeding rate was significantly higher in intervention group (59.8% vs 37%, P=0.003).

CONCLUSIONS

The present study showed that weight and length gain of LBW babies significantly increased by breastfeeding and nutrition education. Therefore, nutrition education on breastfeeding proves to be a strong tool to reduce the high risk of malnutrition and mortality of the LBW babies.

A retrospective analysis of clinical outcome of patients with chemo-refractory metastatic breast cancer treated in a single institution phase I unit

BACKGROUND AND METHODS

Novel approaches to treat chemo-refractory metastatic breast cancer (MBC) are currently under investigation. This retrospective series reviews the outcome of 70 MBC patients who have participated in 30 phase I trials at the Royal Marsden Hospital from 2002 to 2009.

RESULTS

The median treatment lines before phase I trial entry for MBC was 5 (range: 1-12 lines). The overall response rate was 11.4% (95% CI: 4.0-18.9%) and the clinical benefit rate at 4 months was 20% (95% CI: 10.6-29.3). The median time to progression was 7.0 weeks (95% CI: 6.4-7.5) and median overall survival was 8.7 months (95% CI: 7.6-9.8) from start of first phase I treatment. No patients discontinued trial because of treatment-related toxicities. Abnormal lactate dehydrogenase, serum albumin <35 mg per 100 ml, >or=5 previous treatment lines, liver metastases and Eastern Cooperative Group performance status >or=2 at study entry were significantly associated with poor overall survival in multivariate analysis.

CONCLUSION

This retrospective analysis provides evidence that patients with MBC tolerate phase I clinical trials and a significant proportion of patients with chemo-refractory disease, particularly those with triple-negative or Her2-positive breast cancer, may benefit from treatment.

A phase I study evaluating the pharmacokinetics (PK) and pharmacodynamics (PD) of the oral pan-phosphoinositide-3 kinase (PI3K) inhibitor GDC-0941

3538

Background: The PI3K-PTEN-AKT signaling pathway is deregulated in a wide variety of cancers. GDC-0941 is a potent and selective oral inhibitor of class I PI3K and demonstrates activity in a broad range of preclinical models (breast, ovarian, lung, and prostate). Methods: Patients (pts) with histologically confirmed advanced solid tumors and ECOG PS 0–1 were treated with GDC-0941 using a 3+3 escalation design at a single institution. Treatment was a single dose with 1wk washout, followed by GDC-0941 qd on a 3wk on, 1wk off schedule. Objectives were to determine MTD and DLT, evaluate PD endpoints in surrogate (pAKT in platelet rich plasma) and tumor (pAKT and pS6 in paired tumor biopsies and FDG uptake via PET imaging) tissues, and describe anti-tumor activity. Results: Thirteen patients have been enrolled in 4 successive cohorts (15–60 mg qd). GDC-0941 was generally well-tolerated with no drug related Grade 3 or 4 AEs or DLTs to date. Grade 1 diarrhea, nausea, dysgeusia, peripheral sensory neuropathy, dry mouth, thrombocytopenia, and increased aspartate aminotransferase have been observed. Preliminary PK data suggest dose-proportional increases in fasting mean Cmax and AUC. Preliminary PD data show decreased levels of pAKT in platelet rich plasma correlated with GDC-0941 plasma concentrations. GDC-0941 effects on FDG-PET imaging is being assessed, with 1 patient with HER2+ metastatic breast cancer showing a reduction in FDG uptake and improvement of a chest wall lesion (dose level 60 mg qd). Evaluation of PI3K pathway modulation from paired tumor biopsies is underway. Conclusions: GDC-0941 is generally well tolerated when administered qd at doses associated with inhibition of pAKT in surrogate tissues. Evidence of PD activity in tumor tissue has also been observed. Dose-escalation continues and updated PK/PD data will be presented.

[Table: see text]

Persistence of low serum iron and high total iron binding capacity in pregnant women

A cross sectional descriptive type of study was done in 98 women of reproductive age. Among them 25 were in control group of non pregnant women and 73 were pregnant women of 1st, 2nd and 3rd trimester of pregnancy with and without iron supplementation. The period of study was July 2004 to June 2005. The main objective of our study was to compare serum iron and total iron binding capacity in pregnant and non pregnant women. In present study serum iron was significantly increased in 2nd and 3rd trimester of pregnancy that was supplemented with iron when compared with the same category of women who were not supplemented with iron. On the other hand serum total iron binding capacity (TIBC) was significantly increased in 3rd trimester of pregnancy that was not supplemented with iron when compared with the same category of women who were supplemented with iron. It is evident that the significantly low serum iron and high TIBC in pregnant women is due in part to dietary iron deficiency. Therefore, iron therapy in pregnancy is helpful to maintain the serum iron and TIBC nearer to that of non pregnant normal women.

Improving the outcome of patients with castration-resistant prostate cancer through rational drug development

Castration-resistant prostate cancer (CRPC) is now the second most common cause of male cancer-related mortality. Although docetaxel has recently been shown to extend the survival of patients with CRPC in two large randomised phase III studies, subsequent treatment options remain limited for these patients. A greater understanding of the molecular causes of castration resistance is allowing a more rational approach to the development of new drugs and many new agents are now in clinical development. Therapeutic targets include the adrenal steroid synthesis pathway, androgen receptor signalling, the epidermal growth factor receptor family, insulin growth factor-1 receptor, histone deacetylase, heat shock protein 90 and the tumour vasculature. Drugs against these targets are giving an insight into the molecular pathogenesis of this disease and promise to improve patient quality of life and survival. Finally, the recent discovery of chromosomal translocations resulting in the upregulation of one of at least 3 ETS genes (ERG, ETV1, ETV4) may lead to novel agents for the treatment of this disease.

A phase 1, pharmacokinetic (PK) and pharmacodynamic (PD) study of CHIR-258, a novel oral multiple receptor tyrosine kinase (RTK) inhibitor

3043

Background: CHIR-258 is a potent small molecule inhibitor of VEGF, FGF, PDGF and c-KIT RTKs with IC50≤10nM that demonstrates activity in a variety of angiogenesis, tumour and metastasis models. Methods: Patients (pts) with histologically confirmed advanced solid tumors, ECOG PS 0–2 were treated in cohorts of 3–6 with CHIR-258. Treatment was as single daily doses on a repeated 7 days (d) on/7d off schedule (25–100mg), with a subsequent protocol amendment to continuous (cont) daily dosing. The objectives were to determine maximum tolerated dose (MTD) and dose limiting toxicity (DLT), evaluate PK and PD endpoints - ERK phosphorylation in PBL - and describe anti-tumour activity. Results: 35pts (median age 56.5 yrs; 15F/20M) were treated in 4 intermittent dosing cohorts (25, 50, 75, 100 mg/d) and 3 continuous dosing cohorts (100,125, 175 mg/d). The most common drug related adverse events were (grade [gr], number of pts): nausea (gr 1–3, 12); fatigue (gr 1–2, 9); headache (gr 1–3, 8); vomiting (gr 1–2, 7); anorexia (gr 1–2, 7); diarrhoea (gr 1–2, 6); dysgeusia (gr1–2, 6); anaemia (gr 2–3, 4); hypertension (gr 1–3, 3) and reversible asymptomatic drop in left ventricular ejection fraction (gr 2, 2). DLTs were gr 3 hypertension (HTN) in 1 pt with pre-existing HTN (100mg, cont); asymptomatic uncomplicated grade 2 elevation in cardiac troponin I (125mg); gr 3 anorexia/fatigue and gr 3 rise in alkaline phosphatase (both at 175mg). 3 pts have had prolonged stable disease (all 4m+; parotid, renal and imatinib-refractory GIST). The plasma PKs of CHIR-258 were linear over the dose range of 25–175 mg with respect to Cmax and AUC. On d1, the mean Cmax was 13.5(5.3) ng/mL to 109 (26) ng/mL, the mean AUC (0–24) was 224(97.4)ng*h/mL to 1740(466)ng*h/mL, and the t½ was 17h. Trough CHIR-258 concentrations at doses >50 mg/d were above the concentrations known to inhibit target receptor activation in vitro. Data on evaluable samples demonstrate up to 90% inhibition of basal ERK phosphorylation. Conclusions: CHIR-258 was safely administered at continuous daily doses up to 175mg/d. Modulation of p-ERK was demonstrated. Treatment is associated with disease stabilization.

[Table: see text]