Pharmacodynamic Evaluation Research Articles

A comparative in vivo Evaluation of Anti-Alzheimer Activity of Bacopa Extract and its Solid Lipid Nanoparticles

Background: Bacopa monnieri (Brahmi; family Scrophulariaceae) is a well-known plant known for its nootropic activity. Delivery of Bacosides (an active constituent) is limited at the site of action owing to the existence of the Blood-Brain Barrier (BBB). In order to take the Bacoside- Rich Extract (BRE) across BBB, formulated solid lipid nanoparticles (SLNs) were used. Objective: The objective of this work was to evaluate the pharmacokinetic and pharmacodynamic behavior (in vivo potential) of the prepared SLNs containing BRE in comparison to BRE alone for the treatment of Alzheimer’s disease. Methods: Swiss albino male mice (25-30 gm) were used for the study. The pharmacokinetic, as well as pharmacodynamic evaluation of formulated SLNs, were performed in comparison to BRE in a scopolamine-induced amnesia model. Results: BRE-loaded SLNs were found to be significantly more effective than BRE in alleviating neurodegeneration. The pharmacokinetic study revealed the improved bioavailability of prepared SLNs with the potential of sustaining the drug release in mice for an extended period of time. Conclusion: The results demonstrated that the SLNs can be considered as a potential delivery system for taking BRE across the BBB to treat Alzheimer’s disease.

Chemical Fingerprint Profiles and Pharmacodynamic Investigation for Quality Evaluation of Moxa Smoke by UHPLC in a Rat Model of Superficial Infection

Introduction Moxibustion, a traditional Chinese medicine technique, involves the use of moxa smoke from Folium Artemisia argyi to treat various disorders, especially superficial infections. However, there is a higher health risk for people exposed to high levels of moxa smoke for extended durations. Here, we report the first ultra-high-performance liquid chromatography (UHPLC) fingerprint profiles and pharmacodynamic evaluation of moxa smoke, as well as evaluation of its aqueous solution on a rat model of superficial infection. Methods A novel method for moxa smoke fingerprint profiling was developed using UHPLC under characteristic wavelength. Chromatographic peaks were further analyzed by ultra-high-performance liquid chromatography quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF/MS). 12 sample batches obtained from various Chinese provinces were then analyzed using similarity evaluation, clustering analysis, and principal component analysis. The pharmacodynamics of moxa smoke and moxa aqueous solution were investigated on a rat model of acute skin wound infection. Results UHPLC fingerprint profiles of 12 batches of moxa smoke were generated at 270 nm wavelength and 21 chromatographic peaks extracted as common peaks. Similarity between the 12 batches ranged from 0.341 to 0.982. Based on cluster analysis, the 12 batches of moxa smoke samples were clustered into five groups. Principal component analysis showed that the cumulative contribution of the three principal components reached 90.17%. Eigenvalues of the first, second, and third principal components were 10.794, 6.504, and 1.638, respectively. The corresponding variance contribution rates were 51.40%, 30.97%, and 7.80%, respectively. Pharmacological analysis found that wound healing was slow in the model group relative to the mupirocin ointment, moxa smoke, and aqueous moxa smoke solution groups. Histological analysis revealed markedly reduced tissue inflammation in rats treated with moxa smoke or its aqueous solution. Conclusions Moxa smoke and its aqueous solution significantly promote wound healing upon superficial infection. A novel quality control method for moxa smoke was established and evaluated for the first time. As its main effects are unchanged, the transformation of moxa smoke into aqueous moxa smoke improves safety and is a simple and controllable process.

Molecular Imaging, How Close to Clinical Precision Medicine in Lung, Brain, Prostate and Breast Cancers.

Precision medicine is playing a pivotal role in strategies of cancer therapy. Unlike conventional one-size-fits-all chemotherapy or radiotherapy modalities, precision medicine could customize an individual treatment plan for cancer patients to acquire superior efficacy, while minimizing side effects. Precision medicine in cancer therapy relies on precise and timely tumor biological information. Traditional tissue biopsies, however, are often inadequate in meeting this requirement due to cancer heterogeneity, poor tolerance, and invasiveness. Molecular imaging could detect tumor biology characterization in a noninvasive and visual manner, and provide information about therapeutic targets, treatment response, and pharmacodynamic evaluation. This summates to significant value in guiding cancer precision medicine in aspects of patient screening, treatment monitoring, and estimating prognoses. Although growing clinical evidences support the further application of molecular imaging in precision medicine of cancer, some challenges remain. In this review, we briefly summarize and discuss representative clinical trials of molecular imaging in improving precision medicine of cancer patients, aiming to provide useful references for facilitating further clinical translation of molecular imaging to precision medicine of cancers.

Metabolites Identification of Chemical Constituents From the Eggplant (Solanum melongena L.) Calyx in Rats by UPLC/ESI/qTOF-MS Analysis and Their Cytotoxic Activities.

Eggplant (Solanum melongena L.) Calyx is a medicinal and edible traditional Chinese medicine with anti-inflammatory, anti-oxidant, and anti-cancer properties. However, the pharmacodynamic components and metabolic characteristics remain unclear. Amide and phenylpropanoid were the two main constituents, and four amides, including n-trans-p-coumaroyltyramine (1), n-trans-p-coumaroyloctopamine (2), n-trans-p-coumaroylnoradrenline (3), n-trans-feruloyloctopamine (4), and a phenylpropanoid neochlorogenic acid (5) were selected. In this study, these five representative compounds showed cytotoxic activities on A549, HCT116, and MCF7 cells. In addition, the metabolites of 1–5 from the eggplant calyx in rats were identified. In total, 23, 37, 29, and 17 metabolites were separately characterized in rat plasma, urine, feces, and livers, by UPLC/ESI/qTOF-MS analysis. The metabolism of amides and phenylpropanoid was mainly involved in hydroxylation, methylation, glucuronidation, or sulfation reactions. Two hydroxylated metabolites (1-M2 and 2-M3) were clearly identified by comparison with reference standards. Rat liver microsome incubation experiments indicated that P450 enzymes could hydroxylate 1–5, and the methylation reaction of the 7-hydroxyl was also observed. This is the first study on the in vivo metabolism of these compounds, which lays a foundation for follow-up studies on pharmacodynamic evaluations and mechanisms.

Preparation and Evaluation of Intranasal in situ Gel of Bupleuri Radix Volatile Oil and Baicalin

To prepare and evaluate a new formulation of thermosensitive and ion-sensitive in situ gel for nasal administration, using the volatile oil of Bupleuri radix and baicalin, the effective component extracted from Scutellariae radix . Formulation of in situ nasal gel of Bupleuri radix volatile oil and baicalin was prepared by using poloxamer 407 and deacetylated gellan gum as the gel base, 10% pharmasolve and 2% polysorbate 80 as the solubilizer, and 0.8% triethanolamine as the pH regulator. The physical appearance, phase transition temperature, and baicalin release performance of the prepared gel were examined. The pharmacodynamic evaluation was done with the rat fever model developed with dry yeast and the mouse auricle swelling inflammation model. The phase transition temperature of the gel was optimized to be 36 ℃. The release of baicalin from the gel showed obvious features of sustained release, which accorded well the zero-order kinetics equation. The results of experiments with the rat dry yeast fever model and the mouse xylene auricle swelling inflammation model showed that the gel had significant antipyretic and anti-inflammatory effects that were significantly better than those of the groups treated with the blank gel base and the Bupleuri radix and Scutellariae radix granule. Results from the cilia toxicity test showed that the gel did not have obvious toxic effect on toad palate mucosal cilia. The in situ nasal gel of Bupleuri radix volatile oil and baicalin prepared in the study had a rapid onset time, high efficiency, and prolonged release of active ingredients, thus showing promises for further applicational development.

WITHDRAWN: Design and evaluation of GLP-1 receptor G-protein biased agonist with prolonged efficacy on diabetes

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have emerged as potent drug development target for treating diabetes and obesity. Here, we designed and evaluated novel long-acting GLP-1R G protein biased agonist with potent clinical application. GLP-1R G-protein biased sequences were screened via a high-throughput autocrine-based strategy and then fused to Exendin (9-39). These fusion peptides were further performed with site-specific modification. Surface plasmon resonance (SPR) measurements, GLP-1R activation potencies and plasma stability tests were applied to screen optimal candidate. Acute and chronic hypoglycemic and insulinotropic activities of selected agent were evaluated in diabetic and obese rodent animals. AX09 exert highest binding affinities for GLP-1R extracellular domain (GLP-1R ECD). Further in vitro plasma stability and GLP-1R activation assays demonstrated better potency of AX18. Acute pharmacodynamic evaluation of AX18 demonstrated the promising insulinotropic and hypoglycemic activities which were exhibited in a dose-dependent manner. Prolonged hypoglycemic efficacies of AX18 were also observed in both hypoglycemic duration test and multiple oral glucose tolerance tests (OGTTs) in the diabetic mice. Further pharmacokinetic test in cynomolgus monkeys exhibited that the half-life of AX18 was more than 6 days. Once weekly treatment of AX18 in diabetic mice for 8-week achieved significantly improved %HbA1C, insulin resistance, glucose tolerance, β-cells and diabetic retinal injury. Chronic treatment of AX18 in diet-induced obese (DIO) mice also exhibited beneficial efficacies on %HbA1C, inflammation-related factors lowering, and weight gains. AX18, as a novel GLP-1R G protein biased agonist, exhibited potency for treating diabetes mellitus and its complications.

Pharmacodynamic Evaluation of Acalabrutinib in Relapsed/Refractory and Treatment-Naive Patients with Chronic Lymphocytic Leukemia (CLL) in the Phase 1/2 ACE-CL-001 Study

Pharmacodynamic Evaluation of Acalabrutinib in Relapsed/Refractory and Treatment-Naive Patients with Chronic Lymphocytic Leukemia (CLL) in the Phase 1/2 ACE-CL-001 Study

LC-MS/MS assay of riluzole and etoricoxib in rat plasma and brain tissue with applications for sampling and evaluation in pre-clinical rat model of traumatic brain injury

A sensitive and robust liquid chromatography – tandem mass spectrometry (LC-MS/MS) method was developed and validated to simultaneously quantify the concentration levels of selective cyclo-oxygenase- 2 inhibitor, etoricoxib, and glutamate antagonist, riluzole, in rat plasma and brain tissue. Labeled internal standards (IS) etoricoxib D4 and [13C,15N2] riluzole were used for the quantifications of etoricoxib and riluzole, respectively. Analytes riluzole and etoricoxib, as well as their IS's, were separated from rat plasma and brain tissue homogenate by means of liquid – liquid extraction using organic solvent of ethyl acetate. A Waters Acquity UPLC BEH C18 (1.7 µm) column was used for chromatographic separation of analytes on a SCIEX ExionLC AD using a binary solvent system. In conjunction, a SCIEX QTRAP 5500 mass spectrometer was used to quantify etoricoxib at m/z of 359 → 244 (IS of m/z 363 → 248) and riluzole at m/z 235 → 166 (IS of m/z 238 → 169) mass transitions using positive mode electrospray ionization (ESI) with multiple reaction monitoring (MRM). The bioanalytical method was validated over a linear concentration range of 0.25 (LLOQ at average signal to noise >10) – 600 ng/ml in plasma and 0.625 – 1500 ng/g in brain tissue for both analytes. The methods intra/inter-day accuracy and precision are well within the FDA validation recommendations range for chromatographic assays for both riluzole and etoricoxib in rat plasma. A partial validation was conducted within rat brain biomatrix, yielding an acceptable intra-day accuracy and precision for both riluzole and etoricoxib. For riluzole and etoricoxib the average matrix effect and recovery from rat plasma and brain tissue were negligible. This bioanalytical method was effectively applied to perform a pharmacokinetic study of each compound administered concurrently in healthy male Long-Evan (L.E.) rats. This method was developed as a pre-requisite for the pre-clinical pharmacokinetic and pharmacodynamic evaluations of co-treatment with riluzole and etoricoxib in rats with a controlled cortical impact (CCI) induced traumatic brain injury.

Angio-Phenotype of Pediatric Acute Lymphoblastic Leukemia and Pharmacodynamic Evaluation of the Antiangiogenic Activity of Corticosteroids.

Corticosteroids are essential in the treatment of pediatric acute lymphoblastic leukaemia (ALL). Corticosteroid anti-angiogenic activity is postulated but unproven.Objectives: To assess the kinetics of cellular and plasma angiogenic surrogate markers during 7-day prednisone pre-phase/induction therapy in the AIEOP ALL 2000 protocol.Methods: 17 diagnosed common ALL and 12 normal controls were enrolled. Total and viable circulating endothelial cells (CECs) and progenitors (CEPs), vascular endothelial growth factor receptors (VEGFR2, R3), endoglin (CD105), VECadherin (CD144) expression were analyzed by four color flow-cytometry on peripheral blood. Plasma circulating VEGF, VEGFRs and endoglin were analyzed by ELISA. Gene expression of VE-Cadherin, Nanog, RGS5, VEGFR2 and R3 were quantified by Real Time RT-PCR.Results: Total CECs (31 ±8cells/uL), viable CECs (12 ± 5 cells/uL) and CEPs (0.91 ±0.91 cells/uL) were found to be significantly higher in pediatric controls than in adult. At baseline patients demonstrated a statistically higher number of CECs (CD45− CD31+ CD146+ cells) and CEPs (CD133+ cells) p=0.01 and 0.03, compared to controls. CD105, VEGFR-3 and VEGFR-2 expression on leukemic blasts was 91%, 27% and 0% of patients, respectively.After 7 days of prednisone, a statistically significant reduction of total and viable CECs (p= 0.01) and CEPs ( p<0.0001) as well as endothelial cells expressing VEGFR2, R3, and CD105 (p=0.01, p=0.03, p=0.02) was observed. Plasma VEGFR2, VEGFR3, and endoglin showed a trend to decrease at day 8 and 33 but did not reach significance. A statistically significant reduction of blast was also observed.The pro-apototic effect of prednisone was greater on blast compared to lymphocytes.VEGFR-3 gene expression was significantly increased in patients at diagnosis compared to pediatric controls, and significantly reduced on day 8.Conclusions:Increase in CECs, CEPS confirm a pro-angiogenic activity at diagnosis in common ALL. The anti-leukemic effects of prednisone may be linked to its pro-apoptotic and anti-angiogenic activities. Total and viable CECs, CEPs, expression of endoglin and VEGFR3 on blast appear to be suitable angiogenic surrogate biomarkers.

Developing fluoromodule-based probes for in vivo monitoring the bacterial infections and antibiotic responses

Recently, antibiotic resistant has become a serious public health concern, which warrants new generations of antibiotics to be developed. Pharmacodynamic evaluation is crucial in drug discovery processes. Despite numerous advanced imaging systems are available nowadays, technologies for the sensitive in vivo diagnosis of bacterial infections and direct visualization of drug efficacy are yet to be developed. In this study, we have developed novel near-infrared (NIR) fluorogenic probes. These probes are dark in solution but highly fluorescent when bound to the cognate reporter, fluorogen-activating protein (FAP). We established the in vivo bacterial infection model using FAP_dH6.2 recombinantly expressed E. coli and applied this NIR fluoromodule-based system for diagnosing bacterial infections and monitoring disease progressions and its responses to a type of antibiotics through classic mechanism of membrane lysis. This NIR fluoromodule-based system will discover new information on bacterial infections and identify newer antibacterial entities.

Hunting for better biomarkers of response: where is real progress being made in understanding why patients do and don’t respond to I-O therapeutics?

Adil DaudProfessor of Medicine and Dermatology, University of California; and Director of the Melanoma program, Helen Diller Family Cancer Center, UCSFDr Adil Daud is an expert in immunotherapy and has pioneered the development of novel immunotherapeutics and targeted therapies. His fellowship in medical oncology was at the Memorial Sloan Kettering Cancer Center and was a faculty member at the Moffitt Cancer Center in Tampa, Fl. He is currently Professor of Medicine and Dermatology at the University of California, San Francisco. He is the director of the Melanoma Program and melanoma clinical research at the Helen Diller Family Cancer Center at UCSF. He led the development of IL-12 in melanoma and has developed novel technology to deliver it in vivo. He has played a major role in developing PD-1 antibodies in cancer therapy. Recently he has developed novel assays to determine immune responsiveness in vivo. These assays can determine the likelihood of response to immune therapy and provide novel insights into immune drug development. He has collaborated on numerous clinical and translational clinical trials that have yielded insights into the use of immunotherapy.Steven FlingSenior Staff Scientist, Fred Hutchinson Cancer Research Center; and Lab Director, Central Immune Monitoring LabSteven Fling, PhD serves as Lab Director for Central Immune Monitoring Lab (CIML), overseeing correlative biomarker studies for the NCI funded CITN (Cancer Immunotherapy Trials Network) and the industry funded ION (Immune Oncology Network). CITN/ION conducts early-stage, multicenter IO clinical trials, with a focus on agents/combinations to potentiate effective immune responses. Dr. Fling has &gt;24 years research experience in T cell immunobiology, cancer vaccine and immunotherapeutic discovery, including ~13 years managing immunology research labs and directorship of collaborative research networks and consortia. Previously Dr. Fling served as Project Director for the IAVI’s Neutralizing Antibody Consortium, an international consortium working to develop a vaccine for HIV and in 2009 established lab operations at IAVI’s Neutralizing Antibody Center at the Scripps Research Institute (La Jolla, CA). In biotech R&amp;D, Dr. Fling worked on vaccines for cancer and infectious diseases including adjuvant development at Corixa Corp (Seattle, WA) and as an Investigator in the Adjuvant Group for GSK Biologicals.John RossiSenior Director, Department of Translational Medicine, KiteI joined Kite in 2015 after 13 years at Amgen. I am currently a Senior Director in the Department of Translational Medicine at Kite and lead all pharmacology activities related to the clinical development of Kite’s cell therapy pipeline. At Kite, I have built an effective translational team to support the clinical development of axicabtagene ciloleucel (Yescarta&#174;) and KTE-X19 (Tecartus&#174;). My team has contributed directly to the regulatory approval of these products through pharmacokinetic and pharmacodynamic evaluation. Among many achievements at Kite, I have represented the organization through external scientific presentations and collaborative manuscripts with leading academic researchers such as Steven Rosenberg and James Kochenderfer at the NCI. Accomplishments include the discovery of metrics to characterize CAR T based on functionality, novel biomarker knowledge of how CARs work in the clinic, mechanistic information on toxicities and insights into the biology of the TME, including immune checkpoints, and the role of IL-15 in the context of CAR T-cell function.Majid GhoddusiSenior Director, Clinical Biomarkers, Poseida TherapeuticsDr Ghoddusi has over 15 years of experience in some of the most challenging areas of oncology with focus on drug discovery and clinical development. Dr Ghoddusi has broad and overarching insights into unmet therapeutic areas with expertise in translational sciences and clinical biomarker development which allows him to provide unique perspective on how to propel therapeutic projects from discovery to approval. Trained as a translational pathologist he has held numerous positions at large pharmaceutical and small biotech companies including Novartis, Celgene and Juno Therapeutics. His current focus at Poseida Therapeutic is Gene and Cellular Therapy.

Hunting for better biomarkers of response: where is real progress being made in understanding why patients do and don’t respond to I-O therapeutics?

Adil DaudProfessor of Medicine and Dermatology, University of California; and Director of the Melanoma program, Helen Diller Family Cancer Center, UCSFDr Adil Daud is an expert in immunotherapy and has pioneered the development of novel immunotherapeutics and targeted therapies. His fellowship in medical oncology was at the Memorial Sloan Kettering Cancer Center and was a faculty member at the Moffitt Cancer Center in Tampa, Fl. He is currently Professor of Medicine and Dermatology at the University of California, San Francisco. He is the director of the Melanoma Program and melanoma clinical research at the Helen Diller Family Cancer Center at UCSF. He led the development of IL-12 in melanoma and has developed novel technology to deliver it in vivo. He has played a major role in developing PD-1 antibodies in cancer therapy. Recently he has developed novel assays to determine immune responsiveness in vivo. These assays can determine the likelihood of response to immune therapy and provide novel insights into immune drug development. He has collaborated on numerous clinical and translational clinical trials that have yielded insights into the use of immunotherapy.Steven FlingSenior Staff Scientist, Fred Hutchinson Cancer Research Center; and Lab Director, Central Immune Monitoring LabSteven Fling, PhD serves as Lab Director for Central Immune Monitoring Lab (CIML), overseeing correlative biomarker studies for the NCI funded CITN (Cancer Immunotherapy Trials Network) and the industry funded ION (Immune Oncology Network). CITN/ION conducts early-stage, multicenter IO clinical trials, with a focus on agents/combinations to potentiate effective immune responses. Dr. Fling has &gt;24 years research experience in T cell immunobiology, cancer vaccine and immunotherapeutic discovery, including ~13 years managing immunology research labs and directorship of collaborative research networks and consortia. Previously Dr. Fling served as Project Director for the IAVI’s Neutralizing Antibody Consortium, an international consortium working to develop a vaccine for HIV and in 2009 established lab operations at IAVI’s Neutralizing Antibody Center at the Scripps Research Institute (La Jolla, CA). In biotech R&amp;D, Dr. Fling worked on vaccines for cancer and infectious diseases including adjuvant development at Corixa Corp (Seattle, WA) and as an Investigator in the Adjuvant Group for GSK Biologicals.John RossiSenior Director, Department of Translational Medicine, KiteI joined Kite in 2015 after 13 years at Amgen. I am currently a Senior Director in the Department of Translational Medicine at Kite and lead all pharmacology activities related to the clinical development of Kite’s cell therapy pipeline. At Kite, I have built an effective translational team to support the clinical development of axicabtagene ciloleucel (Yescarta&#174;) and KTE-X19 (Tecartus&#174;). My team has contributed directly to the regulatory approval of these products through pharmacokinetic and pharmacodynamic evaluation. Among many achievements at Kite, I have represented the organization through external scientific presentations and collaborative manuscripts with leading academic researchers such as Steven Rosenberg and James Kochenderfer at the NCI. Accomplishments include the discovery of metrics to characterize CAR T based on functionality, novel biomarker knowledge of how CARs work in the clinic, mechanistic information on toxicities and insights into the biology of the TME, including immune checkpoints, and the role of IL-15 in the context of CAR T-cell function.Majid GhoddusiSenior Director, Clinical Biomarkers, Poseida TherapeuticsDr Ghoddusi has over 15 years of experience in some of the most challenging areas of oncology with focus on drug discovery and clinical development. Dr Ghoddusi has broad and overarching insights into unmet therapeutic areas with expertise in translational sciences and clinical biomarker development which allows him to provide unique perspective on how to propel therapeutic projects from discovery to approval. Trained as a translational pathologist he has held numerous positions at large pharmaceutical and small biotech companies including Novartis, Celgene and Juno Therapeutics. His current focus at Poseida Therapeutic is Gene and Cellular Therapy.

Pharmacokinetic and pharmacodynamic evaluation of nasal liposome and nanoparticle based rivastigmine formulations in acute and chronic models of Alzheimer\u2019s disease

With the increasing aging population and progressive nature of the disease, Alzheimer’s disease (AD) poses to be an oncoming epidemic with limited therapeutic strategies. It is characterized by memory loss, behavioral instability, impaired cognitive function, predominantly, cognitive inability manifested due to the accumulation of β-amyloid, with malfunctioned cholinergic system. Rivastigmine, a reversible dual cholinesterase inhibitor, is a more tolerable and widely used choice of drug for AD. However, rivastigmine being hydrophilic and undergoing the first-pass metabolism exhibits low CNS bioavailability. Nanoformulations including liposomes and PLGA nanoparticles can encapsulate hydrophilic drugs and deliver them efficiently to the brain. Besides, the nasal route is receiving considerable attention recently, due to its direct access to the brain. Therefore, the present study attempts to evaluate the pharmacokinetic and pharmacodynamic properties of nasal liposomal and PLGA nanoparticle formulations of rivastigmine in acute scopolamine-induced amnesia and chronic colchicine induced cognitive dysfunction animal models, and validate the best formulation by employing pharmacokinetic and pharmacodynamic (PK-PD) modeling. Nasal liposomal rivastigmine formulation showed the best pharmacokinetic features with rapid onset of action (Tmax = 5 min), higher Cmax (1489.5 ± 620.71), enhanced systemic bioavailability (F = 118.65 ± 23.54; AUC = 35,921.75 ± 9559.46), increased half-life (30.92 ± 8.38 min), and reduced clearance rate (Kel (1/min) = 0.0224 ± 0.006) compared to oral rivastigmine (Tmax = 15 min; Cmax = 56.29 ± 27.05; F = 4.39 ± 1.82; AUC = 1663.79 ± 813.54; t1/2 = 13.48 ± 5.79; Kel (1/min) = 0.0514 ± 0.023). Further, the liposomal formulation significantly rescued the memory deficit induced by scopolamine as well as colchicine superior to other formulations as assessed in Morris water maze and passive avoidance tasks. PK-PD modeling demonstrated a strong correlation between the pharmacokinetic parameters and acetylcholinesterase inhibition of liposomal formulation.

Qualitative and quantitative analysis of nucleosides and nucleobases in Phylloporia ribis by UPLC-Q-TOF-MS and HPLC

The dried fruit body of Phylloporia ribis(Hymenochaetaceae), which prefers to live on the stumps of Lonicera japonica(Caprifoliaceae), has a variety of activities, whereas its pharmacodynamic material basis is not completely clear and there are few reports on its quality control and evaluation. In this study, an UPLC-Q-TOF-MS method was used to analyze the nucleosides and nucleobases in P. ribis and a HPLC method was established for simultaneous determination of 10 nucleosides and nucleobases. MS and MS/MS data were acquired in positive ion mode. Based on the data comparison of the sample and the reference substance, the literature data and the compound databases of ChemSpider and PubChem, 18 nucleosides and nucleobases were identified qualitatively from the water extract of P. ribis for the first time. After optimization, the HPLC was performed using a Welch Ultimate AQ C_(18) column(4.6 mm×250 mm, 5 μm) by gradient elution with acetonitrile and water as mobile phase, the flow rate of 1.0 mL·min~(-1), the detection wavelength of 260 nm, and the column temperature of 30 ℃. Through the investigation of the extraction method, solvent and time, it was determined that the test solution should be obtained by cold water extraction for 18 h. At the present HPLC conditions, 10 components of uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine and thymidine could be well separated(R &gt; 1.5) and showed good linearity(r &gt; 0.999 9) in the concentration ranges of 0.247-24.7, 0.283-28.3, 0.273-27.3, 0.256-25.6, 0.257-25.7, 0.318-31.8, 0.245-24.5, 0.267-26.7, 0.250-25.0 and 0.267-26.7 mg·L~(-1), respectively. The average reco-veries of 10 components were 95.78%-104.5%, and the RSDs were 2.2%-5.2%(n=6). The contents of 10 nucleosides and nucleobases in different samples of P. ribis varied greatly, which were 0.021-0.122, 0.004-0.029, 0.014-0.226, 0.009-0.442, 0.003-0.014, 0.002-0.146, 0.007-0.098, 0-0.054, 0.005-0.069, 0.004-0.081 and 0.072-1.28 mg·g~(-1) for uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine, thymidine and total 10 components, respectively. These results demonstrated that the components had significant differences in the internal quality, and good quality control was needed to ensure the medical efficacy. This study provides a scientific basis for the discovery of pharmacodynamic ingredients, quality control and evaluation of P. ribis.

Pharmacodynamic evaluation of suppression of in vitro resistance in Acinetobacter baumannii strains using polymyxin B-based combination therapy

The emergence of polymyxin resistance in Gram-negative bacteria infections has motivated the use of combination therapy. This study determined the mutant selection window (MSW) of polymyxin B alone and in combination with meropenem and fosfomycin against A. baumannii strains belonging to clonal lineages I and III. To evaluate the inhibition of in vitro drug resistance, we investigate the MSW-derived pharmacodynamic indices associated with resistance to polymyxin B administrated regimens as monotherapy and combination therapy, such as the percentage of each dosage interval that free plasma concentration was within the MSW (%TMSW) and the percentage of each dosage interval that free plasma concentration exceeded the mutant prevention concentration (%T>MPC). The MSW of polymyxin B varied between 1 and 16 µg/mL for polymyxin B-susceptible strains. The triple combination of polymyxin B with meropenem and fosfomycin inhibited the polymyxin B-resistant subpopulation in meropenem-resistant isolates and polymyxin B plus meropenem as a double combination sufficiently inhibited meropenem-intermediate, and susceptible strains. T>MPC 90% was reached for polymyxin B in these combinations, while %TMSW was 0 against all strains. TMSW for meropenem and fosfomycin were also reduced. Effective antimicrobial combinations significantly reduced MSW. The MSW-derived pharmacodynamic indices can be used for the selection of effective combination regimen to combat the polymyxin B-resistant strain.

A phase 1b, open-label, dose-escalation study to evaluate camidanlumab tesirine (Cami) as monotherapy in patients (pts) with advanced solid tumors.

2556 Background: Depletion of tumor-infiltrating CD25+ regulatory T cells (Tregs), which inhibit tumor-specific immune responses, could contribute to tumor eradication. Cami (ADCT-301), an anti-CD25, pyrrolobenzodiazepine-based antibody-drug conjugate, targets CD25+ Tregs. A mouse surrogate has shown potent antitumor activity in solid tumor models. Here we report preliminary data from the monotherapy arm of a phase 1b trial of Cami in pts with selected advanced solid tumors. Methods: The monotherapy dose-escalation part of this open-label study enrolled pts (aged ≥18 years) with selected advanced solid tumors and no suitable existing therapy. The primary objective was to characterize safety and tolerability, and to identify the recommended phase 2 dose of Cami monotherapy. Secondary and exploratory objectives included evaluation of preliminary antitumor activity, pharmacokinetics (PK), pharmacodynamics (PD), and immunogenicity. Pts received Cami every 3 weeks (1 cycle) with dose escalation per a 3+3 design. Disease control rate (DCR) was assessed (complete and partial responses [CR, PR] and stable disease). Results: At data cut-off (Dec 17, 2020), 44 pts were enrolled, with primary tumor types (stage IVA/B: 27 pts; 61.4%) of colorectal (15 pts; 34.1%), pancreatic (14 pts; 31.8%), head and neck, ovarian/fallopian tube, and renal cell carcinoma (all 3 pts; 6.8%), non-small cell lung cancer (2 pts; 4.5%), gastric, esophageal/GEJ, melanoma, and triple-negative breast cancer (each 1 pt; 2.3%). Median (range) age was 60.5 (33–82) years; median (range) number of prior systemic therapies was 4 (1–9). Pts received a median (range) of 2 (1–6) Cami cycles at doses of 20–150 µg/kg. Median (range) treatment duration was 22 (1–178) days. No dose-limiting toxicities were reported. The maximum tolerated dose (MTD) was not reached. All-grade treatment-emergent adverse events (TEAEs) in ≥20% pts were nausea (18 pts; 40.9%), decreased appetite and fatigue (each 16 pts; 36.4%), constipation (13 pts; 29.5%), abdominal pain (11 pts; 25%), and rash (10 pts; 22.7%). The only Grade ≥3 TEAE in ≥10% pts was anemia (5 pts; 11.4%). Grade 3 autoimmune AEs (colitis, immune-mediated AE, systemic inflammatory response syndrome) and neurologic AEs (dysphagia and asthenia, but not GBS) were reported in 3 (6.8%) and 2 (4.5%) pts, respectively. 1 (2.3%) Cami-related TEAE led to treatment withdrawal; no Cami-related TEAEs were fatal. DCR was 25% (95% CI: 11.1, 34.7); 11/44 pts attained stable disease. No pts had CR or PR. Conclusions: Dose escalation of Cami monotherapy is complete. The safety profile is encouraging and MTD was not reached. PK/PD data will be presented. 150 µg/kg is the highest dose investigated for single-agent Cami and the highest to be investigated combined with pembrolizumab in selected advanced solid tumors in the current protocol. Funding: ADC Therapeutics SA NCT03621982. Clinical trial information: NCT03621982.

Safety and efficacy of AK112, an anti-PD-1/VEGF-A bispecific antibody, in patients with advanced solid tumors in a phase I dose escalation study.

2515 Background: AK112 is a tetrameric bispecific antibody targeting PD-1 and VEGF-A. Published data suggests that the combination of anti-VEGF-A with immune checkpoint inhibitor (ICI) therapy produces complementary and synergistic antitumor effects. Given the strong correlation between VEGF-A and PD-1 expression in the tumor microenvironment, it is postulated that the simultaneous blockade of these 2 targets by AK112 as a single agent might achieve higher target binding specificity and produce enhanced antitumor activity, with an improved safety profile, compared to the co-administration of anti-PD-(L)1 and anti-VEGF therapies. Here, we present preliminary safety and efficacy data from a dose escalation study of AK112. Methods: A multicenter, phase I, open-label dose escalation and expansion study in advanced solid tumors that are resistant/refractory to standard therapies, began in December 2019 to determine the safety and efficacy of AK112 (0.3 mg/kg to 30 mg/kg) administered IV every 2 weeks (Q2W) using an accelerated titration followed by 3+3+3 dose escalation design. Selected dose escalation cohorts were expanded to a maximum of 18 subjects with selected solid tumor types for further evaluation of safety, pharmacokinetics (PK), pharmacodynamics (PD), immunogenicity, and anti-tumor activity. Pts with prior exposure to ICI were eligible. PD studies examined serum VEGF levels and PD-1 receptor occupancy (RO) on circulating T-cells as an indication of target engagement. Results: As of 13 Jan 2021, 29 pts, median age 60 years [30-76], have received AK112 at doses of 0.3 mg/kg (n = 1), 1.0 mg/kg (n = 3), 3.0 mg/kg (n = 3), 10.0 mg/kg (n = 13), 20.0 mg/kg (n = 8), and 30.0 mg/kg (n = 1) Q2W. Treatment-related adverse events (TRAEs) occurred in 55.2% of pts. G3 TRAEs occurred in 10.3% [3/29] and treatment-related SAEs occurred in 3.4% [1/29] of pts. There was no G4 TRAE. No DLT occurred. TRAEs leading to treatment discontinuation occurred in 6.9% of pts [2/29]. Most frequent TRAEs were arthralgia (17%), diarrhea (14%), rash (10%), and fatigue (10.3%). Of the 17 evaluable pts treated at doses ≥ 3 mg/kg Q2W, the ORR was 23.5% (4/17) and disease control rate (DCR) was 64.7% (11/17). Among the 4 responders, a responder (endometrial ca) had not received prior ICI or bevacizumab, 2 responders (ovarian ca, mesothelioma) had received prior ICI therapy; and a responder (microsatellite stable colorectal ca) was previously treated with bevacizumab. Conclusions: AK112, up to 20 mg/kg Q2W (inclusive), can be given safely to pts and demonstrated encouraging anti-tumor activity with an ORR of 23.5% when dosed ≥ 3 mg/kg Q2W in a pt population with various solid tumors resistant/relapsed to standard therapies. Enrolment is currently ongoing at 30.0 mg/kg Q2W and in dose escalation cohorts selected for expansion. Updated data, including PK, serum VEGF, and RO will be presented. Clinical trial information: NCT04047290.

BDB001, an intravenously administered toll-like receptor 7 and 8 (TLR7/8) agonist, in combination with pembrolizumab in advanced solid tumors: Phase 1 safety and efficacy results.

2512 Background: BDB001 is an intravenously administered TLR 7/8 dual agonist immune modulator capable of reprogramming dendritic cells to produce antitumor activities. BDB001 monotherapy has demonstrated favorable tolerability and robust systemic immune activation leading to durable clinical responses in a phase I dose escalation trial. Here, we report on the safety and efficacy of BDB001 in combination with pembrolizumab in a phase I dose escalation trial in advanced solid tumors (NCT03486301). Methods: BDB001-101 is a phase 1, open label, dose escalation/expansion trial of BDB001 (IV, Q1W) in combination with pembrolizumab (IV, Q3W) in patients with advanced solid tumors. The primary endpoint was safety and tolerability. Secondary endpoints included efficacy, pharmacokinetics and pharmacodynamic profiling of immune activation. Results: Twenty-three subjects with 13 different tumor types were enrolled across 4 dose levels. Sixty one percent were female, median age was 63 years (range, 33-86), median number of prior therapies was 3 (range, 1-8), and 48% of tumors had progressed on prior anti-PD-(L)1 therapy. Overall, BDB001 in combination with pembrolizumab was well tolerated and dose-limiting toxicities were not observed. The most common treatment related adverse events (TRAEs) were fever (39.1%), fatigue (39.1%), chills/rigor (34.8%), pruritus/rash (21.7%), and nausea (13.0%). Most of these TRAEs were grade 1 or 2 and transient. Only 3 (13.0%) subjects experienced grade 3 TRAEs of fatigue, rash, stomatitis, and alkaline phosphatase elevation. There were no grade 4 or 5 TRAEs. Pharmacodynamic evaluation of plasma cytokine levels showed robust increases in interferon gamma and interferon inducible protein-10 (IP-10) at BDB001 Dose Level 3 and 4. Preliminary efficacy evaluation of the 14 subjects treated at Dose Level 3 and 4 showed durable and deep clinical responses in 4 (29%) subjects with anti-PD-(L)1 mAb refractory melanoma, hepatocellular carcinoma, cholangiocarcinoma, and platinum-resistant ovarian carcinoma. The responses were observed by the initial efficacy assessment at 9-weeks, with some seen as early as 4-weeks. In addition, 4 (29%) subjects had stable disease for a disease control rate of 57%. To date, median time on treatment is 14.4 weeks (range, 6.0 – 42.1+) with 3 subjects still active on treatment. Conclusions: Intravenously administered BDB001 in combination with pembrolizumab is well tolerated. Rapid and deep clinical responses were observed, supported by robust systemic immune activation. BDB001 in combination with pembrolizumab is a promising novel therapeutic option for patients with advanced solid tumors and is being evaluated in an ongoing dose expansion trial. Clinical trial information: NCT03486301.

Pharmacodynamic Evaluation of a Single Dose versus a 24-Hour Course of Multiple Doses of Cefazolin for Surgical Prophylaxis.

The optimal perioperative duration for the administration of cefazolin and other prophylactic antibiotics remains unclear. This study aimed to describe the pharmacodynamics of cefazolin for a single 2 g dose versus a 24 h course of a 2 g single dose plus a 1 g eight-hourly regimen against methicillin-susceptible Staphylococcus aureus. Static concentration time–kill assay and a dynamic in vitro hollow-fibre infection model simulating humanised plasma and interstitial fluid exposures of cefazolin were used to characterise the pharmacodynamics of prophylactic cefazolin regimens against methicillin-sensitive Staphylococcus aureus clinical isolates. The initial inoculum was 1 × 105 CFU/mL to mimic a high skin flora inoculum. The static time–kill study showed that increasing the cefazolin concentration above 1 mg/L (the MIC) did not increase the rate or the extent of bacterial killing. In the dynamic hollow-fibre model, both dosing regimens achieved similar bacterial killing (~3-log CFU/mL within 24 h). A single 2 g dose may be adequate when low bacterial burdens (~104 CFU/mL) are anticipated in an immunocompetent patient with normal pharmacokinetics.

Pharmacokinetic and Pharmacodynamic Evaluation of Ravulizumab in Adults with Severe Coronavirus Disease 2019.

IntroductionTerminal complement amplification is hypothesized to be a key contributor to the clinical manifestations of severe coronavirus disease 2019 (COVID-19). Ravulizumab, a humanized monoclonal antibody that binds with high affinity to complement protein C5 and inhibits terminal complement activation, is being evaluated as a treatment for COVID-19-related severe pneumonia, acute lung injury, and acute respiratory distress syndrome in an ongoing phase 3 randomized controlled trial (ALXN1210-COV-305). To address the overactivation of terminal complement in severe COVID-19 compared to the diseases in which ravulizumab is currently approved, a modified dosing regimen was adopted. This analysis evaluates preliminary pharmacokinetic/pharmacodynamic data to confirm the modified dosing regimen.MethodsWeight-based ravulizumab doses were administered on days 1, 5, 10, and 15. Serum levels of ravulizumab and free C5 were measured before and after administration of ravulizumab and any time on day 22. Free C5 levels < 0.5 μg/mL indicate complete C5 inhibition. The pharmacokinetic target was defined as ravulizumab concentrations at the end of the dosing interval > 175 μg/mL, the concentration above which C5 is completely inhibited.ResultsTwenty-two patients were included in this evaluation. At baseline, mean C5 concentration was 240 ± 67 μg/mL. In all patients and at all individual timepoints after the first dose was administered, ravulizumab concentrations remained > 175 μg/mL and free C5 concentrations remained < 0.5 μg/mL.ConclusionHigh levels of baseline C5 observed in patients with severe COVID-19 contribute to the growing body of evidence that suggests this disease is marked by amplification of terminal complement activation. Data from this preliminary pharmacokinetic/pharmacodynamic evaluation of 22 patients with severe COVID-19 show that the modified ravulizumab dosing regimen achieved immediate and complete terminal complement inhibition, which can be sustained for up to 22 days. These data support the continued use of this dosage regimen in the ongoing phase 3 study.Trial RegistrationClinicalTrials.gov identifier, NCT04369469