Bioanalysis of lanreotide in dog plasma using liquid chromatography-tandem mass spectrometry and its application in a pharmacokinetic study of beagle dogs after single subcutaneous injection.

Lanreotide is similar to a naturally occurring hormone, somatostatin; thus, it may be used to treat acromegaly or metastatic gastroenteropancreatic neuroendocrine tumours. Here, a bioanalytical method coupling ultra-performance liquid chromatography with tandem mass spectrometry to quantify lanreotide and an internal standard (IS) was developed and validated in dog plasma. The plasma samples were extracted using typical protein precipitation processes. The analyte and internal standard were separated on Phenomenex Kinetex® C18 with 0.1% formic acid and acetonitrile in the mobile phase at a flow rate of 0.4 mL/min. The fragmentation of precursor ions to product ions was optimized at m/z 548.8 â†’ 170.0 for lanreotide [M + 2H]2+ and 472.2 â†’ 436.2 for IS [M + H]+. The peak retention times of lanreotide and IS were 1.09 min and 1.22 min, respectively. The calibration curve samples in dog plasma ranged from 0.3 to 1000 ng/mL and showed good linearity, with a correlation coefficient of r2=0.9996. The lower limit of quantitation was 0.3 ng/mL. The intra- and inter-day precision (relative standard deviation) values for each quality control level were < 9.7 % and < 9.3 %, respectively; intra- and inter-day accuracy were < 109.3% and < 110.4%, respectively. Lanreotide in dog plasma was stable in various conditions. The maximum plasma concentration of lanreotide in male beagle dogs after subcutaneous injection of Somatuline® (lanreotide) Autogel 120 mg was 88.1 ng/mL. The half-life (T1/2) of lanreotide in beagle dogs was long, approximately 198.6 h; the area under the plasma-concentration curve from 0 to 840 h (day 35) was 6,995 ng⋅h/mL. This novel quantification method using UPLC-MS/MS was successfully applied to the pharmacokinetic analysis of lanreotide in dog plasma. The results will assist future studies of drug formulation and repurposing.

Quality of life in patients with acromegaly receiving lanreotide autogel: a real-world observational study.

INTRODUCTION: Patients with acromegaly have substantially reduced quality of life (QoL). This study evaluated QoL in patients with acromegaly treated with lanreotide autogel. MATERIAL AND METHODS: This was a prospective, non-interventional, observational, multi-centre study conducted in Poland (NCT02396966). We included patients with acromegaly, who received treatment with lanreotide autogel 120mg for ≥ 3 months and < 3 years. Patients were assessed approximately every 4-5months for twoyears (six visits). QoL was measured with the Acromegaly Quality of Life Questionnaire (AcroQoL). RESULTS: Of 152 patients enrolled from November 2014 to May 2018 in 37 centres, 24 were excluded due to major protocol deviations. The results are reported for the study population (n = 128). At baseline, the median [95% confidence interval (CI)] time from diagnosis was 3.3 (2.8, 4.2)years, and the median time since lanreotide initiation was 13.4 (9.9, 17.3) months. Symptoms of acromegaly were present at baseline in 86% of patients (headache, 57%; sweating, 58%; joint symptoms, 64%); symptoms remained unchanged at two years in 82% of patients. At baseline, 27% of patients had hormonal control (growth hormone < 2.5 µg/L and insulin-like growth factor-1 within the normal range); hormonal control status did not change during the study period in over 81% of patients. At baseline, 88% of patients were either very satisfied or satisfied with treatment; treatment satisfaction was unchanged in 62% of patients over the study period. Mean (95% CI) AcroQoL scores at baseline were as follows: total, 50.3 (47.3, 53.3); physical dimension, 48.8 (45.2, 52.4); psychological dimension, 51.3 (48.2, 54.4); appearance subdimension, 40.7 (37.5, 43.8); and personal relations subdimension, 62.5 (58.8, 66.2). The psychological appearance subscore improved by 3.8 points (1.2, 6.5) over the two years; scores in the remaining dimensions and subdimensions did not change substantially. The total AcroQoL score remained unchanged over the twoyears, regardless of prior acromegaly treatment, surgery or radiotherapy, hormonal control, or lanreotide dosing interval. No new safety findings were identified. CONCLUSIONS: AcroQoL total scores and physical and psychological subscores remained stable but impaired among patients with long-lasting acromegaly treated with lanreotide autogel for two years. The psychological appearance subdimension improved numerically.

The Chemical Synthesis of Knob Domain Antibody Fragments.

Cysteine-rich knob domains found in the ultralong complementarity determining regions of a subset of bovine antibodies are capable of functioning autonomously as 3-6 kDa peptides. While they can be expressed recombinantly in cellular systems, in this paper we show that knob domains are also readily amenable to a chemical synthesis, with a co-crystal structure of a chemically synthesized knob domain in complex with an antigen showing structural equivalence to the biological product. For drug discovery, following the immunization of cattle, knob domain peptides can be synthesized directly from antibody sequence data, combining the power and diversity of the bovine immune repertoire with the ability to rapidly incorporate nonbiological modifications. We demonstrate that, through rational design with non-natural amino acids, a paratope diversity can be massively expanded, in this case improving the efficacy of an allosteric peptide. As a potential route to further improve stability, we also performed head-to-tail cyclizations, exploiting the proximity of the N and C termini to synthesize functional, fully cyclic antibody fragments. Lastly, we highlight the stability of knob domains in plasma and, through pharmacokinetic studies, use palmitoylation as a route to extend the plasma half-life of knob domains in vivo. This study presents an antibody-derived medicinal chemistry platform, with protocols for solid-phase synthesis of knob domains, together with the characterization of their molecular structures, in vitro pharmacology, and pharmacokinetics.

In Vitro Selection of Macrocyclic d/l-Hybrid Peptides against Human EGFR.

d/l-Hybrid peptides are an attractive class of molecular modality because they are able to exhibit high proteolytic stability and unique structural diversity which cannot be accessed by those consisting of only proteinogenic l-amino acids. Despite such an expectation, it has not been possible to devise de novo d/l-hybrid peptides capable of disrupting the function of a protein target(s) due to the lack of an effective method that reliably constructs a highly diverse library and screens active species. Here we report for the first time construction of a library consisting of 1012 members of macrocyclic d/l-hybrid peptides containing five kinds of d-amino acids and performance of the RaPID selection against human EGFR as a showcase to uncover PPI (protein-protein interaction) inhibitors.

Intratumoral distribution of YSNSG cyclopeptide in a mouse melanoma model using microdialysis.

The YSNSG peptide is a synthetic cyclopeptide targeting αvß3 integrin with antitumor activity. Previous study has determined main pharmacokinetic parameters in plasma and in tissue in healthy animals using microdialysis. First we aim to assess the impact of a 20 mg/kg dosage instead of 10 mg/kg in tumor growth inhibition. Secondly we aim to investigate the YSNSG peptide distribution in two different tumor regions in animals with melanoma. C57BL/6 mice were exposed at Days 8, 10 and 12 after melanoma cells implantation (B16F1) to different dosage of YSNSG peptide or control, respectively (n = 10 per group). Data analysis was performed at D16, 20 and 24 with a Nonlinear Mixed-Effects (NLME) approach. For pharmacokinetic study n = 8 mice (same disease condition) received YSNSG peptide by intravenous after insertion of two microdialysis probes in central peripheral region of tumor, respectively. Plasma and tissue samples were collected during 2 h. A non-compartmental analysis was performed to determine main pharmacokinetic parameters. There was a significant tumor growth inhibition in mice receiving 20 mg/kg vs Control (p < 0.02). Main plasma parameters were half-life elimination 25.8 ± 8.2 min, volume of distribution 11.9 ± 0.4 mL, clearance 19.8 ± 9.4 mL/h and area under the curve 1,173.6 µg.min/mL. Penetration rate of the YSNSG peptide from plasma to tumor tissue were 3.3 ± 2.1% and 3.4 ± 2.7% in central and peripheral, respectively. Contrary to subcutaneous distribution in healthy animals the distribution of the YSNSG peptide into tumoral tissue is low but seems non-heterogeneous between central and peripheral tumor region.

Rheumatoid meningitis sine arthritis.

Rheumatoid meningitis is a rare and very serious extra-articular manifestation of rheumatoid arthritis. We present a case of a 7()year-old female with no history of arthritis who developed stroke-like symptoms, seizures, psychosis and compulsive behavior. Serial brain magnetic resonance images (MRI) over four months demonstrated progressive interhemispheric meningeal thickening. She had mild lymphocytic pleocytosis on the cerebrospinal fluid analysis and serum anti-cyclic citrullinated peptide antibodies resulted positive in high titers. She underwent a brain biopsy showing necrotizing granulomas consistent with rheumatoid meningitis. Her symptoms resolved with treatment with glucocorticoids and cyclophosphamide. She has not been diagnosed with rheumatoid arthritis even after 1 year of follow up. Clinicians should be aware of the possibility of rheumatoid meningitis without rheumatoid arthritis and keep it on the differential for patients with aseptic meningitis and otherwise negative work up.

Comparison of Adults With Polyarticular Juvenile Idiopathic Arthritis to Adults With Rheumatoid Arthritis: A Cross-sectional Analysis of Clinical Features and Medication Use.

BACKGROUND/OBJECTIVE: Many individuals with juvenile idiopathic arthritis (JIA) have persistent disease into adulthood. Polyarticular JIA (pJIA) is often mislabeled as rheumatoid arthritis (RA) in adult rheumatology clinics, and treatment for adult pJIA patients is not well defined. We aimed to describe clinical features and medication use in the adult pJIA population in relation to an RA control cohort. METHODS: We performed a cross-sectional study of 45 adults with pJIA and 94 with RA seen from 2013 to 2017. Clinical characteristics including RA classification criteria were compared using χ and McNemar tests. Medication use was analyzed focusing on tumor necrosis factor inhibitor (TNFi) survival, and an accelerated failure-time model was developed for time to methotrexate initiation. RESULTS: Polyarticular JIA patients were less likely to be rheumatoid factor or cyclic citrullinated peptide antibody positive; fewer than half of pJIA subjects met the RA 2010 American College of Rheumatology/European League Against Rheumatism Classification Criteria. Time from diagnosis to methotrexate initiation was associated with longer disease duration in both groups (p < 0.01). Current TNFi use was more prevalent in pJIA patients (49% vs. 18%, p < 0.01), and TNFi use, particularly for etanercept, was sustained longer with a median drug survival of 4.41 years compared with 0.70 years in RA patients (p < 0.01). CONCLUSIONS: Although often considered together in adult rheumatology practice, adults with pJIA are distinct from patients with RA. Medication use markedly differed between the 2 populations with greater prevalence and duration of TNFi use in pJIA patients. Further study is needed to improve outcomes in this unique population.

An optimized LC-MS/MS method for determination of HYNIC-3PRGD2, a new promising imaging agent for tumor targeting, in rat plasma and its application.

HYNIC-3PRGD2 is used to prepare a new 99mTc-radiolabeled tracer. HYNIC-3PRGD2, which has a high binding affinity for the integrin αvß3 due to its special structure, has become a promising tumor imaging agent for diagnosis and monitor of the clinical response to therapeutic effects of anti-tumor agents. Here, we developed and validated a method for determination of HYNIC-3PRGD2 concentration in rat plasma using ultra-high performance liquid chromatography-tandem mass spectrometry system. Following sample extraction by methanol precipitation, satisfactory separation through chromatography was achieved on an hydrophilic reverse-phase C18 column AQ (2.1 mm × 100 mm, 2.7 µm) at a flow rate of 0.2 mL·min-1 with an gradient elution using mobile phase consisting of ultrapure water and acetonitrile fortified with 0.1% formic acid respectively. The calibration curve was developed over a linear range of 3.125-100 ng·mL-1 with the lower limit of quantification of 3.125 ng·mL-1. The HYNIC-3PRGD2 and its internal standard c(RGDfK)(RK5) were detected and quantified with the multiple reaction monitoring (MRM) mode on a triple-quadrupole tandem mass spectrometer. This method was successfully validated and applied for pharmacokinetic evaluation of HYNIC-3PRGD2 during pre-clinical experiments.

Quantitative analysis of the cyclic peptide GG-8-6 in rat plasma using LC-MS/MS and its application to a pharmacokinetic study.

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. The discovery of new anticancer compounds is of great significance. GG-8-6, cyclo-(Val1-Leu2-Pro3-Ile4-Leu5-Leu6-Leu7-Val8-Leu9), a new synthetic cyclic peptide, might be a potential candidate for developing new anti-HCC drugs. GG-8-6 shares no structural homology to current anti-HCC drugs. Therefore, it was necessary to develop a quantitative method for the determination of GG-8-6 in vivo. Herein, a simple, specific and sensitive liquid chromatographic method with tandem mass spectrometric detection (LC-MS/MS) was developed and validated for the analysis of GG-8-6 in rat plasma. GG-8-6 and the internal standard (IS), A6, cyclo-(Val1-Leu2-Pro3-Ala4-Leu5-Leu6-Leu7-Val8-Leu9), were extracted from rat plasma by ethyl acetate. Chromatographic separation was performed on an Agilent Eclipse XDB-C18 column (4.6 × 150 mm, 5 µm) with a mobile phase consisting of acetonitrile-water containing 0.1% formic acid (90:10, v/v) with isocratic elution at a flow rate of 0.5 mL/min for 8.0 min. Multiple reaction monitoring (MRM) mode was performed with ion pairs of m/z: 974.8 → 861.8 for GG-8-6 and 932.7 → 819.8 for A6. The selectivity, matrix effects, recovery, intra- and inter-day precision and accuracy were validated with acceptable results in accordance with the US Food and Drug Administration guidelines. The calibration curve was linear (r2 > 0.99) over a concentration range of 1-1000 ng/mL with a lower limit of quantification (LLOQ) of 1 ng/mL. The method was successfully applied to the pharmacokinetic study of GG-8-6 in rats.

Sensitive quantification of the somatostatin analog AP102 in plasma by ultra-high pressure liquid chromatography-tandem mass spectrometry and application to a pharmacokinetic study in rats.

AP102 is a di-iodinated octapeptide somatostatin agonist (SSA) designed to treat acromegaly and neuroendocrine tumors. A sensitive and selective method was validated for the quantification of AP102 in plasma following the European Medicines Agency (EMA) and Food and Drug Administration (FDA) guidelines. Sample preparation was performed using solid-phase extraction microplates. Chromatographic separation was achieved on an ultra-high pressure liquid chromatography (UHPLC) C18 column in 6.0 minutes. The compounds were quantified using multiple reaction monitoring on a tandem quadrupole mass spectrometer with 13 C,15 N-labeled AP102 as internal standard. Calibration ranged from 50 to 10000 pg/mL. The lower limit of quantification (LLOQ) was measured at 20 pg/mL, and robust analytical performances were obtained with trueness at 99.2%-100.0%, intra-assay imprecision at 2.5%-4.4%, and inter-assay imprecision at 8.9%-9.7%. The accuracy profiles (total error) built on the 3 concentrations levels showed accuracy within the 70%-130% range. AP102 is remarkably stable since no proteolytic fragments were detected on plasma samples analyzed by Orbitrap-MS. Pharmacokinetic studies were conducted in rats, after single dose (1, 3, and 10 µg/kg, sc) and continuous subcutaneous administration (osmotic minipumps for 28 days, 3.0 or 10.0 µg/kg/h). AP102 showed a rapid absorption by the subcutaneous route (Tmax : 15-30 minutes) and a fast elimination (t1/2 : 33-86 minutes). The PK profile of AP102 exhibited a mean clearance of 1.67 L/h and a mean distribution volume at steady state of 7.16 L/kg, about 10-fold higher than those observed with other SSA or non- and mono-iodinated AP102. LogD7.4 determination confirmed the lipophilic properties of AP102 that might influence its distribution in tissues.

Cyclic peptide-poly(HPMA) nanotubes as drug delivery vectors: In vitro assessment, pharmacokinetics and biodistribution.

Size and shape have progressively appeared as some of the key factors influencing the properties of nanosized drug delivery systems. In particular, elongated materials are thought to interact differently with cells and therefore may allow alterations of in vivo fate without changes in chemical composition. A challenge, however, remains the creation of stable self-assembled materials with anisotropic shape for delivery applications that still feature the ability to disassemble, avoiding organ accumulation and facilitating clearance from the system. In this context, we report on cyclic peptide-polymer conjugates that self-assemble into supramolecular nanotubes, as confirmed by SANS and SLS. Their behaviour ex and in vivo was studied: the nanostructures are non-toxic up to a concentration of 0.5 g L-1 and cell uptake studies revealed that the pathway of entry was energy-dependent. Pharmacokinetic studies following intravenous injection of the peptide-polymer conjugates and a control polymer to rats showed that the larger size of the nanotubes formed by the conjugates reduced renal clearance and elongated systemic circulation. Importantly, the ability to slowly disassemble into small units allowed effective clearance of the conjugates and reduced organ accumulation, making these materials interesting candidates in the search for effective drug carriers.

Smoking and susceptibility to rheumatoid arthritis in a Swedish population-based case-control study.

Smoking is one of the most established risk factors for rheumatoid arthritis (RA). The aim of this study was to estimate how age at smoking debut, smoking cessation, duration, intensity, and cumulative dose of smoking influence the risk of developing anti-citrullinated peptide antibodies (ACPA) positive and ACPA negative RA. The present report is based on a Swedish population-based, case-control study with incident cases of RA (3655 cases, 5883 matched controls). Using logistic regression models, subjects with different smoking habits were compared regarding risk of developing the two variants of RA, by calculating odds ratios (OR) with 95% confidence intervals (CI). Smoking increased the risk of developing both ACPA positive (OR 1.9, 95% CI 1.7-2.1) and ACPA negative RA (OR 1.3, 95% CI 1.2-1.5). For both subsets of RA, there seemed to be a threshold (~ 2.5 pack years for ACPA positive RA and ~ 5 pack years for ACPA negative RA) below which no association between smoking and RA occurred. A dose-response association was observed between cumulative dose of smoking and risk of developing ACPA positive RA (p value for trend < 0.0001). Duration of smoking had a higher influence on the association between smoking and RA than did intensity of smoking. For both subsets of RA, the detrimental effect of smoking decreased after smoking cessation. Twenty years after smoking cessation, there was no longer an association between smoking and risk of ACPA negative RA, whereas the association between smoking and ACPA positive RA risk persisted and was dependent on the cumulative dose of smoking. Smoking increases the risk of both subsets of RA with a more pronounced influence on the risk of ACPA positive RA. Preventive measures in order to reduce smoking are essential and may result in a decline in RA incidence.

Rheumatoid disease: an unusual cause of relapsing meningoencephalitis.

A 73-year-old man presented with three episodes of dysphasia and disinhibited behaviour, a single seizure and transient ischaemic attack-like events characterised by right arm and/or leg weakness. These episodes were separated by month-long asymptomatic intervals. Medical history included rheumatoid arthritis, which was clinically quiescent on leflunomide.Repeated cerebrospinal fluid examination showed a persistent lymphocytosis with mildly reduced glucose and elevated protein; oligoclonal bands and viral PCR were negative. MRI of the brain was initially normal, but 7 months after initial presentation revealed meningeal enhancement with bifrontal cortical hyperintensities on T2/fluid-attenuated inversion recovery. Brain biopsy demonstrated necrotising granulomatous meningitis with mixed T cell and B cell infiltrates and without evidence of vasculitis or infection. Serum anticyclic citrullinated peptide antibodies were strongly positive.The diagnosis of rheumatoid meningoencephalitis was made on the basis of brain biopsy findings and serological evidence of active rheumatoid disease. Steroids and rituximab therapy were started leading to clinical stabilisation.

Enhanced Permeability and Binding Activity of Isobutylene-Grafted Peptides.

We present a new peptide-macrocyclization strategy with an isobutylene graft. The reaction is mild and proceeds rapidly and efficiently both for linear and cyclic peptides. The resulting isobutylene-grafted peptides possess improved passive membrane permeability due to the shielding of the polar backbone of the amides, as demonstrated by NMR spectroscopy and molecular dynamics simulations. The isobutylene-stapled structures are fully stable in human plasma and in the presence of glutathione. This strategy can be applied to bioactive cyclic peptides such as somatostatin. Importantly, we found that structural preorganization forced by the isobutylene graft leads to a significant improvement in binding. The combined advantages of directness, selectivity, and smallness could allow application to peptide macrocyclization based on this attachment of the isobutylene graft.

A Retrospective Study: The Significance of Combined Testing of Serum Markers for Diagnosis of Rheumatoid Arthritis.

BACKGROUND There have been few studies on the value of various antibody combinations in rheumatoid arthritis (RA) diagnosis, and a lack of studies with large sample sizes, especially in the Chinese population. This study retrospectively evaluated the diagnostic value of a combined assay of five auto-antibodies [anti-cyclic citrullinated peptide (anti-CCP), anti-keratin (AKA), anti-RA 33, glucose-6-phosphate isomerase (GPI), and rheumatoid factor (RF)] for RA. MATERIAL AND METHODS Data were obtained from 5,725 patients with rheumatic diseases in Southwest Hospital of Chongqing from 2011 to 2014. Detection of the five serological markers was performed for all study patients using the appropriate method for each antibody. RESULTS It was found that of the 5,725 patients, the positive rates for RF, anti-CCP, anti-RA 33, AKA, and GPI were 52.5%, 40.1%, 12.8%, 12.0%, and 50.0% respectively. In RA patients, the positive rates were 83.3%, 68.5%, 16.6%, 20.8%, and 77.9% respectively, which were all significantly higher than those detected in patients with the other diseases (p<0.01). The areas under the receiver operator characteristic (ROC) curve for RF, anti-CCP, anti-RA 33, AKA, and GPI were 0.857, 0.831, 0.528, 0.602, and 0.822 respectively, indicating that these five serological markers display favorable diagnostic value for RA. There were positive correlations between anti-CCP antibody and RF and GPI (p<0.01) and between RF and GPI (p<0.01), but no correlation between anti-RA 33 and AKA (p<0.01). The specificity of the combination of anti-CCP, AKA, and GPI was 100% for RA diagnosis. CONCLUSIONS The combined assay of serological markers significantly improved the diagnostic specificity for RA. The diagnostic value of RF for RA was the highest and the combined assay for anti-CCP, AKA, and GPI had the highest specificity for RA diagnosis.

Population Pharmacokinetic and Pharmacodynamic Modeling of LY2510924 in Patients With Advanced Cancer.

The objectives of this study were to characterize the pharmacokinetics (PK) of LY2510924, a potent peptide antagonist of the CXCR4 receptor, after subcutaneous administration in patients with advanced cancer forms and quantify LY2510924 stimulatory effects on the mobilization of cells bearing the cluster of differentiation 34 (CD34) as an indirect reflection of the chemokine C-X-C motif ligand 12/CXCR4 axis inhibition. LY2510924 PK were best characterized by a two-compartment model with first-order absorption and dose-dependent clearance predicting steady state after three daily doses and little accumulation (accumulation ratio <1.17). The dynamics of CD34+ cell counts were best characterized with a precursor model with reversible transfer from the precursor to the central compartment and LY2510924-driven stimulation of cell mobilization. Model-based simulations show that once-daily doses of 20 mg LY2510924 produce maximum CD34+ cell response and that peak effect typically occurs after three daily doses and slowly wanes over time.

Phase II study of lanreotide autogel in Japanese patients with unresectable or metastatic well-differentiated neuroendocrine tumors.

Background Lanreotide is a long-acting somatostatin analog with demonstrated efficacy against enteropancreatic neuroendocrine tumor (NET) in the phase III (CLARINET) study. Materials and Methods In this single-arm study, Japanese patients with grade (G) 1/G2 NET received lanreotide (120 mg/4 weeks) for 48 weeks. Those who completed the study were enrolled in a long-term extension study. The primary endpoint was the clinical benefit rate (CBR) defined as a complete response, partial response (PR), or stable disease (SD) over 24-weeks. Secondary endpoints included progression-free survival (PFS), objective response rate (ORR), safety, and pharmacokinetics. Results Thirty-two patients were recruited at 10 sites. The full analysis set (FAS) comprised 28 patients. Primary tumors were located in pancreas (12 patients), foregut (non-pancreas, lung; 1), midgut (2), hindgut (8), and unknown (5). Four patients had gastrinoma of the functional NET, and 3 had multiple endocrine neoplasia type 1. In the FAS, 39.3% had progressive disease at baseline. The CBR at 24 weeks was 64.3% (95% confidence interval; CI: 44.1-81.4), and median PFS was 36.3 weeks (95% CI: 24.1-53.1). PR was confirmed in 1 patient at 60 weeks during the extension study (ORR: 3.6%). Frequent adverse events related to lanreotide included injection site induration (28.1%), faeces pale (18.8%), flatulence (12.5%), and diabetes mellitus (12.5%). Conclusions The efficacy and safety of lanreotide in this study indicated its usefulness as a treatment option for Japanese NET patients. TRIAL REGISTRATION: JapicCTI-132,375, JapicCTI-142,698.

First plasma and tissue pharmacokinetic study of the YSNSG cyclopeptide, a new integrin antagonist, using microdialysis.

The YSNSG peptide is a synthetic peptide targeting αvß3 integrin. This peptide exhibits promising activity in vitro and in vivo against melanoma. To determine pharmacokinetic parameters and predictive active doses in the central nervous system (CNS) and subcutaneous tissue (SC), we conducted microdialysis coupled with pharmacokinetic modeling and Monte Carlo simulation. After a recovery period of surgical procedures, a microdialysis probe was inserted in the caudate and in subcutaneous tissue. Plasma samples and dialysates collected 5h after YSNSG intravenous administration (10mg/kg) were analyzed by UPLC-MS/MS. A nonlinear mixed-effect modeling approach implemented in Monolix® 2016R1 was performed. Model selection and evaluation were based on the usual diagnostic plot, precision and information criteria. The primary plasma and tissue pharmacokinetic parameters were comparable with those of other integrin antagonists, such as cilengitide or ATN-161. Tissue/plasma and brain/plasma area under the curve (AUC) ratio were 66.2±21.6% and 3.6±4.7%, respectively. Two models of 2-compartments with an additional microdialysis compartment, parameterized as rate constants (k for elimination, k12/k21 and k13/k31 for distribution) and volumes (central V1 and peripheral microdialysis compartment V3) with zero-order input were selected to describe the dialysate concentrations in CNS and SC. The inter-individual variability (IIV) was described by exponential terms, and residual variability was described by a combined additive and proportional error model. Individual AUC (plasma and tissues) values were derived for each animal using the Empirical-Bayes-Estimates of the individual parameters. The regimens needed to achieve an in vitro predetermined target concentration in tissues were studied by Monte Carlo simulations using Monolix® 2016R1. YSNSG pharmacokinetic parameters show promising results in terms of subcutaneous disposition. Further investigations into such processes as encapsulation and intratumoral disposition are currently being conducted.

Design, synthesis and structure-activity relationship study of wollamide B; a new potential anti TB agent.

Wollamide B is a cationic antimycobacterial cyclohexapeptide that exhibits activity against Mycobacterium bovis (M. bovis) (IC50 of 3.1 µM). Aiming to define its structural activity relationship (SAR), optimizing potency and pharmacokinetic properties, libraries of analogues were synthesized following a standard Fmoc-based solid phase peptide synthesis approach. The antimycobacterial activities of wollamide B and all the synthesized analogues were tested against Mycobacterium tuberculosis (Mtb) H37Rv. Parallely, in vitro drug metabolism and pharmacokinetic (ADME) profiling was done for the synthesized compounds to evaluate their drug likeness. Among the 25 synthesized wollamides five of them showed potent activities with MICs ≤ 3.1 µM and found to be nontoxic against human HepG2 cells up to 100 µM. The results of the in vitro ADME profiling revealed the remarkable plasma stability and very good aqueous solubility of the class in general while the metabolic stability was found to be moderate to low. Of particular note, compounds 7c (MIC = 1.1 µM) and 13c (0.6 µM) that exhibited good balance of antimycobacterial activity vs. optimal pharmacokinetic properties could be used as a new lead for further development.

Anti-CCP antibodies are not a marker of severity in established rheumatoid arthritis: a magnetic resonance imaging study / O anti-CCP não é um marcador de gravidade da artrite reumatoide estabelecida: um estudo de ressonância magnética

ABSTRACT Introduction: The presence of anti-CCP is an important prognostic tool of rheumatoid arthritis (RA). But research is still ongoing on its relationship with disease activity and functional capacity. Objectives: To study the relationship between anti-CCP and disease activity, functional capacity and structural damage indexes, by means of conventional radiography (CR) and magnetic resonance imaging (MRI), in cases of established RA. Methods: Cross-sectional study with RA patients with 1–10 disease duration. Participants underwent clinical evaluation with anti-CCP. Disease activity was assessed using the Clinical Disease Activity Index (CDAI), and functional capacity through the Health Assessment Questionnaire (HAQ). CR analysis was carried out by the Sharp van der Heijde index (SvdH), and MRI analysis by RAMRIS (Rheumatoid Arthritis Magnetic Resonance Image Scoring). Results: We evaluated 56 patients, with a median (IqR) age of 55 (47.5–60) years; 50 (89.3%) participants were female and 37 (66.1%) were positive for anti-CCP. Medians (IqR) of CDAI, HAQ, SvdH and RAMRIS were 14.75 (5.42–24.97) 1.06 (0.28–1.75), 2 (0–8) and 15 (7–35), respectively. There was no association between anti-CCP and CDAI, HAQ and SvdH and RAMRIS scores. Conclusion: Our results have not established an association of anti-CCP with the severity of disease. To date, we cannot corroborate anti-CCP as a prognostic tool in patients with established RA.

RESUMO Introdução: A presença do anti-CCP constitui importante ferramenta prognóstica da artrite reumatoide (AR), mas ainda se investiga sua relação com a atividade da doença e a a capacidade funcional. Objetivos: Estudar a relação do anti-CCP com os índices de atividade da doença, de capacidade funcional e de dano estrutural, por meio de radiografia convencional (RC) e de ressonância magnética (RM), em AR estabelecida. Métodos: Estudo transversal com pacientes com AR, com um a 10 anos de doença. Os participantes foram submetidos à avaliação clínica com pesquisa do anti-CCP. A atividade de doença foi avaliada por meio do Clinical Disease Activity Index (CDAI) e a capacidade funcional por meio do Health Assessment Questionnaire (HAQ). A análise da RC foi feita pelo índice de Sharp van der Heijde (SmvH) e da RM pelo Sistema de Pontuação de Imagem por Ressonância Magnética na Artrite Reumatoide (RAMRIS, Rheumatoid Arthritis Magnetic Resonance Image Scoring). Resultados: Foram avaliados 56 pacientes, com mediana (IIq) de 55 (47,5-60,0) anos, 50 (89,3%) do sexo feminino e 37 (66,1%) anti-CCP positivos. As medianas (IIq) do CDAI, do HAQ, de SmvH e do RAMRIS foram de 14,75 (5,42-24,97), 1,06 (0,28-1,75), 2 (0-8) e 15 (7-35), respectivamente. Não houve associação do anti-CCP com o CDAI, com o HAQ e com os escores SmvH e RAMRIS. Conclusão: Nossos resultados não estabeleceram a associação do anti-CCP com a gravidade da doença. Até o momento, não podemos corroborar o anti-CCP como uma ferramenta prognóstica em AR estabelecida.