Favorable Pharmacokinetic Parameters Research Articles

In Silico Structure-Activity Study of Selected Triterpenoids as Potential Inhibitors of Mycolic Acid Transporter of Mycobacterial MmpL3 Receptor Protein

Structural features of the triterpenoid skeleton that are necessary for antimycobacterial activity are not well understood. Following the isolation of the triterpenoids ergosterol-5,8-endoperoxide, 6β-hydroxykulactone, 12β-hydroxykulactone, (24R)-24,25-epoxycycloartan-3-one and (3β,24R)-24,25-epoxycycloartan-3-ol, and (3β,24R)-24,25-epoxycycloartan-3-acetate with varying antimycobacterial activity ranging between MIC of 1 µg/ml to128 µg/ml prompted us to study this class of compounds further to shade light on the structural features necessary for their antimycobacterial activity. This in silico study involved docking the triterpenoids on the mycobacterial multi-pharmacophore receptor protein MmpL3. The docking results were compared with the MmpL3 receptor protein co-crystallized TB drug candidate, AU1235, (1-(2-adamantyl)-3-[2,3,4-tris(fluoranyl)phenyl] urea). The virtual screening revealed key structural features in the triterpenoid skeleton, including the C-3 keto and β-hydroxy group on C-3 or C-6, as important for antimycobacterial activity. Also, the decreased binding affinity for compounds 2 and 7 with an acetate group on C-3 were in tandem with those observed in vitro. Toxicity predictions revealed that this class of compounds had no mutagenic effects and displayed favorable pharmacokinetic parameters. The study reveals the potential of the triterpenoid skeleton exemplified by the readily available ergosterol-5,8-endoperoxide as a useful scaffold in searching and developing effective therapeutic lead entities to facilitate anti-tuberculosis drug discovery.

The TGFβ type I receptor kinase inhibitor vactosertib in combination with pomalidomide in relapsed/refractory multiple myeloma: a phase 1b trial

Functional blockade of the transforming growth factor-beta (TGFβ) signalling pathway improves the efficacy of cytotoxic and immunotherapies. Here, we conducted a phase 1b study (ClinicalTrials.gov., NCT03143985) to determine the primary endpoints of safety, tolerability, and maximal tolerated dose (200 mg twice daily) for the orally-available TGFβ type I receptor kinase inhibitor vactosertib in combination with pomalidomide in relapsed and/or refractory multiple myeloma (RRMM) patients who had received ≥2 lines of chemoimmunotherapy. Secondary endpoints demonstrated sustained clinical responses, favorable pharmacokinetic parameters and a 6-month progression-free survival of 82%. Vactosertib combined with pomalidomide was well-tolerated at all dose levels and displayed a manageable adverse event profile. Exploratory analysis indicated that vactosertib co-treatment with pomalidomide also reduced TGFβ levels in patient bone marrow as well as the level of CD8+ T-cells that expressed the immunoinhibitory marker PD-1. In vitro experiments indicated that vactosertib+pomalidomide co-treatment decreased the viability of MM cell lines and patient tumor cells, and increased CD8+ T-cell cytotoxic activity. Vactosertib is a safe therapeutic that demonstrates tumor-intrinsic activity and can overcome immunosuppressive challenges within the tumor microenvironment to reinvigorate T-cell fitness. Vactosertib offers promise to improve immunotherapeutic responses in heavily-pretreated MM patients refractory to conventional agents.

Abstract PO3-26-11: Enhancing endoplasmic reticulum stress for treating endocrine therapy resistant breast cancers driven by mutant estrogen receptors

Abstract Background: Estrogen receptor alpha (ERα) mutations are common (30-40%) in metastatic endocrine therapy-resistant breast cancers (ETR-BC), enable resistance to endocrine therapies and are the molecular drivers of ETR-BC. We had previously shown that an oligobenzamide, ERX-41, could enhance endoplasmic reticulum stress in ETR-BCs driven by mutant (MT) ERα, resulting in cancer cell death in vitro and and in vivo. To enable clinical translation of ERX-41, we performed lead optimization, followed by preclinical and IND-enabling studies. Methods: Over 2000 oligo-benzamides were designed, synthesized and tested in multiple BC models including those that express WT-ERα (MCF7, and ZR75) and BC models with acquired resistance (MCF7-Tam, and MCF7-LTLT) and engineered models that express MT-ERα (MCF7-ERα-D538G, MCF7-ERα-Y537S, ZR75-ERα-D538G, ZR75-ERα-Y537S). For our lead compound, mechanistic validation studies were performed using CRISPR LIPA mutants, RT-qPCR and Western blotting. Explants, organoids, cell line-(CDX) and patient-derived (PDX) xenografts were used to test the ex vivo and in vivo effectiveness of our lead compound as a monotherapy and in combination with abemaciclib. Results: Testing of >2000 synthesized oligo-benzamides identified a lead compound, ERX-315, that had broad and potent activity (IC50 between 20-100 nM) against both WT and MT (mutant) ERα-driven BC cells in in vitro assays. CRISPR KO of LIPA (which encodes lysosomal acid lipase (LAL) in BC cells abrogated cytotoxic response to ERX-315, validating LIPA as the molecular target of ERX-315. Ultrastructural and molecular studies confirm that ERX-315 induces significant endoplasmic reticulum stress, leading to a shutdown of de novo protein synthesis and apoptotic cell death in BC. Importantly, ERX-315 does not induce endoplasmic reticulum stress or cell death in normal cells and is non-toxic in animal models. We have shown that this capacity of ERX-315 to induce endoplasmic reticulum stress is unique among drugs targeting ERα, including selective ERα modulators and degraders, such as GDC-0180, AZD-9496 and fulvestrant. ERX-315 has potent anti-proliferative activity against MT-ERα-driven BC, as seen in genetically modified cell lines both grown as monolayer or spheroids in vitro, patient derived explants (PDEs) ex vivo and cell line derived (CDX) and patient-derived (PDX) xenografts in vivo. The combination of ERX-315 and CDK4/6 inhibitor abemaciclib was synergistic in decreasing the proliferation of both endocrine therapy-sensitive and endocrine therapy-resistant BC cells, in vitro, in xenograft models in vivo, and in primary patient-derived explants ex vivo. We are currently optimizing both the synthesis of ERX-315 using GMP process for kilogram scale production and validated methods for pharmacokinetic studies. We have developed formulations for both intravenous and oral administration with favorable pharmacokinetic parameters and proven utility of the formulated ERX-315 against CDX and PDX tumors in vivo. Toxicity studies in dogs and rodents have demonstrated >8-fold therapeutic to toxicity window. A phase I clinical trial is planned to be open to enrollment by Q1 2024. Conclusions: We have identified a lead compound ERX-315, which represents a novel class of agent that induce catastrophic levels of ER stress resulting in cancer cell death and that can effectively work against multiple forms of ETR-BC, including those driven by MT-ERα. Preclinical studies, GMP manufacturing, formulation and IND-enabling studies are being completed in time for the commencement of the phase I clinical trial by Q1 2024. Citation Format: Suryavathi Viswanadhapalli, Karla Parra, Tae-Kyung Lee, Rahul Gopalam, Kara Kassees, Tanner Reese, Gaurav Sharma, Xihui Liu, Xue Yang, ChiaYuan Chen, Carlos Roggero, Liping Chen, Sautam Bhattacharya, Uday Pratap, Russell Hayward, Sharron Gargosky, Jung-Mo Ahn, Ganesh V. Raj, Ratna Vadlamudi. Enhancing endoplasmic reticulum stress for treating endocrine therapy resistant breast cancers driven by mutant estrogen receptors [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-26-11.

A Phase I Study of KIN-3248, an Irreversible Small-molecule Pan-FGFR Inhibitor, in Patients with Advanced FGFR2/3-driven Solid Tumors.

Despite efficacy of approved FGFR inhibitors, emergence of polyclonal secondary mutations in the FGFR kinase domain leads to acquired resistance. KIN-3248 is a selective, irreversible, orally bioavailable, small-molecule inhibitor of FGFR1-4 that blocks both primary oncogenic and secondary kinase domain resistance FGFR alterations. A first-in-human, phase I study of KIN-3248 was conducted in patients with advanced solid tumors harboring FGFR2 and/or FGFR3 gene alterations (NCT05242822). The primary objective was determination of MTD/recommended phase II dose (RP2D). Secondary and exploratory objectives included antitumor activity, pharmacokinetics, pharmacodynamics, and molecular response by circulating tumor DNA (ctDNA) clearance. Fifty-four patients received doses ranging from 5 to 50 mg orally daily across six cohorts. Intrahepatic cholangiocarcinoma (48.1%), gastric (9.3%), and urothelial (7.4%) were the most common tumors. Tumors harbored FGFR2 (68.5%) or FGFR3 (31.5%) alterations-23 (42.6%) received prior FGFR inhibitors. One dose-limiting toxicity (hypersensitivity) occurred in cohort 1 (5 mg). Treatment-related, adverse events included hyperphosphatemia, diarrhea, and stomatitis. The MTD/RP2D was not established. Exposure was dose proportional and concordant with hyperphosphatemia. Five partial responses were observed; 4 in FGFR inhibitor naïve and 1 in FGFR pretreated patients. Pretreatment ctDNA profiling confirmed FGFR2/3 alterations in 63.3% of cases and clearance at cycle 2 associated with radiographic response. The trial was terminated early for commercial considerations; therefore, RP2D was not established. Preliminary clinical data suggest that KIN-3248 is a safe, oral FGFR1-4 inhibitor with favorable pharmacokinetic parameters, though further dose escalation was required to nominate the MTD/RP2D. KIN-3248 was a rationally designed, next generation selective FGFR inhibitor, that was effective in interfering with both FGFR wild-type and mutant signaling. Clinical data indicate that KIN-3248 is safe with a signal of antitumor activity. Translational science support the mechanism of action in that serum phosphate was proportional with exposure, paired biopsies suggested phospho-ERK inhibition (a downstream target of FGFR2/3), and ctDNA clearance may act as a RECIST response surrogate.

Evaluation of In vitro anti-inflammatory activity and In-silico pharmacokinetics and molecular docking study of Horsfieldia iryaghedhi

Background: Phytochemicals are still a valuable source to develop clinically important drugs in treating chronic and acute diseases. Inflammation is a response to an injurious stimulus of the body and novel therapeutic agents are needed to alleviate the condition with minimum side effects. Aims and Objectives: To investigate in vitro anti-inflammatory activity of methanol and aqueous leaf, bark, and combination extracts of plant Horsfieldia iryaghedhi by heat-induced egg albumin denaturation method and to analyze the phytochemicals of Horsfieldia iryaghedhi for their anti-inflammatory potential against cyclooxygenase- 2 (COX-2) using molecular docking. Methodology: Matured and fully expanded fresh leaves and barks of H. iryaghedhi were collected, and the extractions were obtained cold maceration using 99.9% methanol and distilled water as solvents. A concentration series was then developed, and the anti-inflammatory activity was evaluated against Diclofenac sodium as the positive control, using the heat-induced egg albumin denaturation method. Further, selected phytochemicals were tested against COX-2 enzyme (PDB ID: 5IKR) using site-specific molecular docking with autodock vina and the binding energies and pharmacokinetic and toxicity parameters were evaluated. Results: The methanol and aqueous extracts have shown a moderate to strong concentration-dependent anti-inflammatory activity with reference to standard Diclofenac sodium (IC50 116.4 μg/ml) and Methanol bark extract exhibited potent anti-inflammatory activity compared to other extracts (IC50 293 μg/ml). Further, Methanol and aqueous extracts showed a statistically significant correlation between concentration and percentage inhibition (p<0.05, R2 ≈1). The molecular docking results suggest that the phytochemicals available on the plant have possible COX-2 inhibitory activity and the compounds selected (Methyl 2,4-dihydroxy-6-methylbenzoate and N, N-Dimethyl-5-methoxy tryptamine) even got favourable toxicity and pharmacokinetic parameters confirming their drugability. Conclusion: Methanol bark extract of Horsfieldia iryaghedhi have marked in vitro anti-inflammatory activity. The results indicate a solid possibility of lead discovery of anti- inflammatory agents from the bark and leaves of Horsfieldia iryaghedhi. However, further molecular dynamics studies and in vivo tests may be required to confirm the findings.

Highlights on the Development, Related Patents, and Prospects of Lenacapavir: The First-in-Class HIV-1 Capsid Inhibitor for the Treatment of Multi-Drug-Resistant HIV-1 Infection.

The multidrug-resistant (MDR) human immunodeficiency virus 1 (HIV-1) infection is an unmet medical need. HIV-1 capsid plays an important role at different stages of the HIV-1 replication cycle and is an attractive drug target for developing therapies against MDR HIV-1 infection. Lenacapavir (LEN) is the first-in-class HIV-1 capsid inhibitor approved by the USFDA, EMA, and Health Canada for treating MDR HIV-1 infection. This article highlights the development, pharmaceutical aspects, clinical studies, patent literature, and future directions on LEN-based therapies. The literature for this review was collected from PubMed, authentic websites (USFDA, EMA, Health Canada, Gilead, and NIH), and the free patent database (Espacenet, USPTO, and Patent scope). LEN has been developed by Gilead and is marketed as Sunlenca (tablet and subcutaneous injection). The long-acting and patient-compliant LEN demonstrated a low level of drug-related mutations, is active against MDR HIV-1 infection, and does not reveal cross-resistance to other anti-HIV drugs. LEN is also an excellent drug for patients having difficult or limited access to healthcare facilities. The literature has established additive/synergistic effects of combining LEN with rilpivirine, cabotegravir, islatravir, bictegravir, and tenofovir. HIV-1 infection may be accompanied by opportunistic infections such as tuberculosis (TB). The associated diseases make HIV treatment complex and warrant drug interaction studies (drug-drug, drug-food, and drug-disease interaction). Many inventions on different aspects of LEN have been claimed in patent literature. However, there is a great scope for developing more inventions related to the drug combination of LEN with anti-HIV/anti-TB drugs in a single dosage form, new formulations, and methods of treating HIV and TB co-infection. Additional research may provide more LEN-based treatments with favorable pharmacokinetic parameters for MDR HIV-1 infections and associated opportunistic infections such as TB.

Small Ceria Nanoclusters with High ROS Scavenging Activity and Favorable Pharmacokinetic Parameters for the Amelioration of Chronic Kidney Disease.

The over production of reactive oxygen species (ROS) plays a critical role in the progression of chronic kidney disease (CKD). Organic ROS scavengers currently used for CKD treatment do not satisfy low dosage and high efficiency requirements. Ceria nanomaterials featured with renewable ROS scavenging activity are potential candidates for CKD treatment. Herein, a method for the synthesis of ceria nanoclusters (NCs) featured with small size of ≈1.2 nm is reported. The synthesized NCs are modified by three hydrophilic ligands with different molecular weights, including succinic acid (SA), polyethylene glycol diacid 600 (PEG600), and polyethylene glycol diacid 2000 (PEG2000). The surface modified NCs exhibit excellent ROS scavenging activity due to the high Ce3+ /Ce4+ ratio in their crystal structures. Compared with bigger-sized ceria nanoparticles (NPs) (≈45 nm), NCs demonstrate smoother blood concentration-time curve, lower organ accumulation, and faster metabolic rate superiorities. The administration of NCs to CKD mice, especially PEG600 and PEG2000 modified NCs, can effectively inhibit oxidative stress, inflammation, renal fibrosis, and apoptosis in their kidneys. Due to these benefits, the constructed NCs can ameliorate the progression of CKD. These findings suggest that NCs is a potential redox nanomedicine for future clinical treatment of CKD.

Abstract 3427: ICP-490 is a highly potent and selective IKZF1/3 degrader with robust anti-tumor activities against multiple myeloma and non-Hodgkin’s lymphoma

Abstract Background: Cereblon (CRBN)-targeting immunomodulatory drugs (IMiDs), i.e., thalidomide and lenalidomide, play pivotal roles in treating multiple myeloma (MM) patients. This class of drugs induce rapid ubiquitination and degradation of two lymphoid transcription factors (IKZF1 and IKZF3) by recruiting them to CRBN-CRL4 E3 ubiquitin ligase, which result in pleiotropic anti-tumor effects including autonomous tumor cell death and immune activation. However, prolonged IMiD treatment eventually becomes resistant and leads to tumor relapse in MM patients, mostly due to down-regulation of CRBN. All approved IMiDs also exert adverse effects such as teratogenicity, attributed to CRBN-mediated degradation of neo-substrates SALL4, PLZF1 and ΔNp63/TAp63. Here we report the development of a novel selective IKZF1/3 degrader ICP-490, which can robustly inhibit MM and NHL tumor growth, and overcome lenalidomide resistance. Results: ICP-490 induces potent, deep, and selective degradation of IKZF1 and IKZF3 with sub-nanomolar IC50, but no significant degradation of IKZF2, IKZF4, GSPT1, SALL4 and PLZF1. Cell viability assays reveal robust in vitro efficacies of ICP-490 against various MM and NHL(DLBCL) cell lines with nanomolar IC50. It also exhibits potent anti-proliferative activity in lenalidomide-resistant cell lines. In contrast to its tumor killing effect, ICP-490 shows no cytotoxicity against normal human cells, such as HEK293 and PBMC cells. ICP-490 induces IKZF1/3 degradation in distinct human lymphocyte lineages, leads to immune cell activation with elevated IL-2 and IFN-γ production and down-regulation of TNF-α in PBMC. The immune modulation activity of ICP-490 has also been illustrated in a combinatory treatment with daratumumab, where low dose of ICP-490 leads to robust induction of IL-2 and granzyme B, and much improved efficacy of daratumumab in MM cell line NCI-H929. In vivo efficacy studies have further confirmed the effectiveness of ICP-490 against MM and DLBCL xenografts, including MM1.S, MM1.R, NCI-H929 multiple myeloma lines, and TMD-8, WSU-DLCL2 DLBCL lines. ICP-490 also eradicates lenalidomide-resistant NCI-H929 xenografts. ICP-490 has overall favorable pharmacokinetic parameters with high oral bioavailability. Nonclinical safety evaluations of ICP-490 exhibit acceptable drug tolerability in SD rats and cynomolgus monkeys. Conclusions: ICP-490 is a highly potent, orally bioavailable, next-generation CRBN-targeting IMiD with selective IKZF1/3 degradation. In various MM and NHL tumor models, it demonstrates superior tumor killing activities than currently approved IMiDs, including overcoming lenalidomide resistance. ICP-490 is now in phase I clinical trial. Citation Format: Ruixia Liang, Yucheng Pang, Yingrui Han, Haipeng Xu, Zuopeng Wang, Richard Liu, Charles Ying Wang, Jason Bin Zhang, Xiangyang Chen, Davy Xuesong Ouyang. ICP-490 is a highly potent and selective IKZF1/3 degrader with robust anti-tumor activities against multiple myeloma and non-Hodgkin’s lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3427.

A Study on Pharmacokinetic Functionalities and Safety Margins of an Optimized Simvastatin Nanoformulation.

A pharmaceutical formulation with favorable pharmacokinetic parameters is more likely to be efficacious and safe to overcome the failures of the drug resulting from lack of efficacy, poor bioavailability, and toxicity. In this view, we aimed to evaluate the pharmacokinetic functionalities and safety margin of an optimized CS-SS nanoformulation (F40) by in vitro/in vivo methods. The everted sac technique was used to evaluate the improved absorption of a simvastatin formulation. In vitro protein binding in bovine serum and mice plasma was performed. The formulation's liver and intestinal CYP3A4 activity and metabolic pathways were investigated by the qRT-PCR technique. The excretion of cholesterol and bile acids was measured to demonstrate the formulation's cholesterol depletion effect. Safety margins were determined by histopathology as well as fiber typing studies. In vitro protein binding results revealed the existence of a high percentage of free drugs (22.31 ± 3.1%, 18.20 ± 1.9%, and 16.9 ± 2.2%, respectively) compared to the standard formulation. The controlled metabolism in the liver was demonstrated from CYP3A4 activity. The formulation showed enhanced PK parameters in rabbits such as a lower Cmax, clearance, and a higher Tmax, AUC, Vd, and t1/2. qRT-PCR screening further proved the different metabolic pathways followed by simvastatin (SREBP-2) and chitosan (PPAR-γ pathway) in the formulation. The results from qRT-PCR and histopathology confirmed the toxicity level. Hence, this pharmacokinetic profile of the nanoformulation proved it has a unique synergistic hypolipidemic modality.

Incidence of breakthrough fungal infections on isavuconazole prophylaxis compared to posaconazole and voriconazole.

Invasive fungal infections (IFIs) are a common infectious complication during the treatment of acute myeloid leukemia (AML), high-risk myelodysplastic syndrome (MDS) or post hematopoietic cell transplantation (HCT). For these patients, the National Comprehensive Cancer Network recommends posaconazole or voriconazole for IFI prophylaxis. In clinical practice, however, there has been increased use of isavuconazole due to favorable pharmacokinetic and pharmacodynamic parameters despite limited data for this indication. The comparative prophylactic efficacy of antifungals in this patient population has not been reported, and an analysis is warranted. This retrospective, matched cohort, single-center study, included AML, MDS, or HCT patients who began treatment or underwent transplant between January 1, 2015 and July 31, 2021. Isavuconazole patients were matched 1:2 with patients receiving posaconazole or voriconazole prophylaxis. A total of 126 patients were included, 42 received isavuconazole, 81 received posaconazole, and three received voriconazole. The majority of patients were male receiving secondary IFI prophylaxis while receiving steroids for treatment of GVHD. The incidence of possible, probable or proven IFI was 16.7% in the isavuconazole group compared to 10.7% in the posaconazole and voriconazole group (OR 1.28, 95% CI -0.9-1.4; p = .67). Hepatotoxicity occurred in 16 total patients, 14 receiving posaconazole and two receiving isavuconazole. Patients who received isavuconazole prophylaxis during AML induction therapy or post-HCT experienced a similar incidence of breakthrough fungal infections compared to those who received posaconazole or voriconazole. These results suggest no difference in antifungal prophylactic efficacy; however larger prospective comparative studies are needed.

Compositional Analysis of Essential Oils from Two Mentha Species and in silico Study on their Major Volatile Constituents against Polycystic Ovary Syndrome

Background: Polycystic ovarian syndrome (PCOS) is defined by excessive production and/or secretion of androgenic hormones in women. This disease has a complicated nature, so its control is difficult and challenging. Therefore, many women use complementary therapies to support medical treatment, one of which is the consumption of mint plants. Objective: This study aimed to characterize the chemical composition of peppermint (Mentha piperita L.) and spearmint (Mentha spicata L.) oils, to assess the binding of constituents of the oils to the androgen receptor as well as their pharmacokinetic features. Methods: The essential oils were isolated by water distillation and then analyzed using GC-MS and GCFID. Thereafter, in silico binding studies were performed between the main volatile constituents and human androgen receptors using Autodock Vina. Besides, the pharmacokinetic properties of the selected compounds were evaluated using SwissADME. Results: GC analyses showed the presence of 19 and 23 constituents out of the total components (accounting for 94.7% and 97.6%, respectively), with carvone (73.0%), and menthone (33.1%) and menthol (29.3%) as the major compounds in spearmint and peppermint oils, respectively. Moreover, molecular docking studies revealed that carvone has the lowest binding energy to the androgen receptor. On the other hand, all tested compounds finally exhibited favorable pharmacokinetic parameters. Conclusion: The present study virtually indicated that the main volatile constituent in the spearmint oil, i.e., carvone, could probably cause a beneficial effect on PCOS.

<em>In silico</em> pharmacokinetic and toxicological study of Flavone analogues

Flavone analogs are natural compounds of the flavonoid class that have a wide range of biological activities. The present study aimed to predict, with the aid of in silico methodologies, the oral bioavailability and pharmacokinetic and toxicological analyzes for three flavone analogues (apigenin, chrysin and luteonlin). The study revealed that the analogues have good oral availability, favorable pharmacokinetic and toxicological parameters. The Virtual Screening performed to predict oral bioavailability revealed that all analogues did not violate Lipinski's Rule. The in silico pharmacokinetic study revealed that all analogues have high intestinal absorption, do not cross the blood-brain barrier, are permeable by Caco-2 cells and do not inhibit P-glycoprotein. The in silico ADME study showed that all analogues inhibit the enzymes of the cytochrome P450 complex (CYP4501A2, CYP4502C9, CYP4502C19, CYP4503A4) and not only the CYP4502D6 enzyme. The in silico Toxicology study indicated that the analogues do not show toxicity by the AMES Test and are not carcinogenic. Apigenin and chrysin have low toxicity, while luteolin has moderate toxicity.

<em>In silico</em> pharmacokinetic and toxicological study of Cinnamic Acid analogues

Cinnamic acid analogs are natural phenolic compounds that have a wide range of biological and therapeutic activities. The present work aimed to predict, through in silico methodologies, the oral bioavailability and pharmacokinetic and toxicological analyzes for four cinnamic acid analogues (caffeic acid, ferulic acid, p-coumaric acid and synaptic acid). The study revealed that the analogues have good oral bioavailability, favorable pharmacokinetic and toxicological parameters. The Virtual Screening performed to predict oral bioavailability indicated that all analogues do not violate Lipinski's Rule. The in silico ADME study of pharmacokinetic parameters showed that all derivatives have high intestinal absorption, are permeable by Caco-2 cells, do not cross the blood-brain barrier, do not inhibit P-glycoprotein. There will be no inhibition of the cytochrome P450 complex isoenzymes (CYP450). The in silico Toxicological study revealed that the analogues do not have toxicity by the AMES Test, are not carcinogenic and do not present acute oral toxicity.

Discovery of [18F]ACI‐12589, a Novel and Promising PET‐Tracer for Alpha‐Synuclein

AbstractBackgroundParkinson’s disease (PD) and other synucleinopathies such as Multiple System Atrophy (MSA) involve a progressive accumulation of a‐synuclein (a‐syn) inclusions that correlates with disease stage and clinical manifestations. The development of a PET agent capable of imaging a‐syn inclusions would significantly aid in differential diagnosis, staging, and monitoring possible benefits of candidate therapeutic agents targeting a‐syn. Due to the generally lower pathologic burden of a‐syn inclusions relative to other brain proteinopathies, a reliable a‐syn PET tracer must display high binding affinity and selectivity for its intended target.MethodUsing our proprietary Morphomer® library of low‐molecular weight and conformation‐specific ligands, compounds with good affinity and target occupancy were identified. We then iteratively performed medicinal chemistry optimization cycles to further improve on‐target binding properties and selectivity based on radiobinding and classical and high‐resolution autoradiography results. Optimized compounds were then assessed further for off‐target activities and evaluated for their brain pharmacokinetic properties in non‐human primates (NHPs). The clinical candidate [18F]ACI‐12589 was subsequently advanced through preclinical assessment prior to evaluation in a clinically diverse set of synucleinopathy subjects and controls.ResultPromising chemical scaffolds with high‐affinity binding to pathological a‐syn in tissue homogenates and sections have been optimized. Particularly, ACI‐12589 demonstrated improved target occupancy on different synucleinopathy samples, including PD and MSA, with a binding pattern aligning closely with the distribution of pathological a‐syn. Moreover, ACI‐12589 demonstrated selectivity for a‐syn versus other potential amyloid pathologies including amyloid‐beta, Tau, and TDP‐43. In NHPs [18F]ACI‐12589 revealed good brain uptake, homogenous distribution and fast washout. Initial results from the ongoing clinical trials confirm favorable pharmacokinetic parameters in patients, including rapid signal equilibration, potentially allowing short scan times. Moreover, initial clinical data in MSA patients indicate that [18F]ACI‐12589 uptake occurs in brain areas affected by the disease process based on clinical manifestations.Conclusion[18F]ACI‐12589 displays preclinical and clinical characteristics deemed necessary to become a reliable PET radiotracer for the imaging of a‐syn inclusions. Interestingly, ex‐vivo data from different synucleinopathy tissues is in accordance with the promising clinical data in MSA that will be presented by R. Smith et al. at this conference.

Quinoline-Dihydropyrimidin-2(1H)-one Hybrids: Synthesis, Biological Activity, and Mechanistic Studies.

A novel class of quinoline-dihydropyrimidin-2(1H)-one (DHPM) hybrids was synthesized and in vitro antiplasmodial activity was evaluated against chloroquine sensitive (D10) and chloroquine resistant (Dd2) strains of Plasmodium falciparum, the human malaria parasite. The antiplasmodial activity was compared to previously reported DHPM based molecular hybrids. Dual mode of antiplasmodial action of the most active member has been evaluated through heme binding study and in silico docking in the active site of dihydrofolate enzymes (wild-type as well as mutant). Favourable pharmacokinetic parameters were predicted in the ADMET evaluation. The new hybrids were also tested against a number of DNA and RNA viruses. No antiviral activity was found, except for one hybrid that showed mild inhibitory activity against two strains of cytomegalovirus (AD-169 and Davis), The most active hybrid was found to be a selective inhibitor of the growth of P. falciparum as well as a modest inhibitor of varicella zoster virus in HEL cells. Cytotoxicity of all hybrids was assessed in HEL, HeLa, Vero, MDCK, and CRFK cell cultures.

Design, synthesis, in vitro antiproliferative evaluation and in silico studies of new VEGFR-2 inhibitors based on 4-piperazinylquinolin-2(1H)-one scaffold

Angiogenesis is essential in the growth of solid tumors which need oxygen and nutrients supply to grow in size. The VEGF/VEGFR-2 signaling pathway plays an important role in tumor angiogenesis. Sorafenib is an FDA approved cancer therapeutic with activity against many protein kinases, including VEGFR. We designed 4-piperazinylquinolin-2(1H)-ones with variable aromatic moieties and Mannich bases as Sorafenib analogues as potential inhibitors of angiogenesis. In this study, we investigated the impact of replacing the linker aromatic ring with cyclic tertiary amines and the effect of incorporation of variably substituted distal rings. We hypothesized that cyclic tertiary amines would improve pharmacokinetic properties and contribute to enzyme interactions. Two series of piperazinylquinolinone-based compounds were synthesized, characterized, and evaluated for bioactivity against adenocarcinoma EKVX NSCLC and T-47D breast cancer cells. Ability to inhibit VEGFR-2 and apoptosis were investigated and molecular docking into the enzyme active site and theoretical ADME properties were determined. Notably, amongst series I three compounds exhibited higher anticancer activity than Staurosporine against EKVX NSCLC adenocarcinoma cell line. In series II, nine compounds exhibited higher antiproliferative activity than Staurosporine against T-47D breast cancer cell line. Two compounds; 5d and 7z exhibited lower toxicity against normal cell line (MCF 10A) than Staurosporine. Compound 7z was the most potent agent with IC50 38.76 nM. Moreover, 7z showed VEGFR-2 inhibitory activity higher than sorafenib and induced remarkable levels of both early and late apoptosis (2.82% and 21.30%, respectively). Hence, 5d and 7z are considered promising VEGFR-2 inhibitors with high efficacy against adenocarcinoma EKVX and T-47D breast cancer cells. The target compounds also possessed favorable physicochemical properties and pharmacokinetic parameters These studies further suggested that the 4-piperazinylquinolin-2(1H)-one derivatives developed in this study play a critical role in modulating VEGFR, and guide the design of innovative anticancer therapies.

Design, synthesis, and evaluation of potent RIPK1 inhibitors with in vivo anti-inflammatory activity

RIPK1 plays a key role in the necroptosis pathway that regulates inflammatory signaling and cell death in various diseases, including inflammatory and neurodegenerative diseases. Herein, we report a series of potent RIPK1 inhibitors, represented by compound 70. Compound 70 efficiently blocks necroptosis induced by TNFα in both human and mouse cells (EC50 = 17–30 nM). Biophysical assay demonstrates that compound 70 potently binds to RIPK1 (Kd = 9.2 nM), but not RIPK3 (Kd > 10,000 nM). Importantly, compound 70 exhibits greatly improved metabolic stability in human and rat liver microsomes compared to compound 6 (PK68), a RIPK1 inhibitor reported in our previous work. In addition, compound 70 displays high permeability in Caco-2 cells and excellent in vitro safety profiles in hERG and CYP assays. Moreover, pre-treatment of 70 significantly ameliorates hypothermia and lethal shock in SIRS mice model. Lastly, compound 70 possesses favorable pharmacokinetic parameters with moderate clearance and good oral bioavailability in SD rat. Taken together, our work supports 70 as a potent RIPK1 inhibitor and highlights its potential as a prototypical lead for further development in necroptosis-associated inflammatory disorders.

Molecular Docking of the Cardenolides of Asclepias subulata in the Human p53 Protein Reveals an Interaction in the Cleft of the Y220C Mutant

Background and Objective: The objective of the present study is to use docking and ADME analysis to determine if the cardenolides of Asclepias subulata are potential stabilizing drugs of the p53-Y220C mutant. Materials and Methods: Two different receptors, wild-type p53, and the mutant p53-Y220C, were used for docking. Three independent stochastic series were performed, with 60,000 poses considered, and the 30 best poses were selected. ADME analysis was performed using SwissADME. Results: Docking experiments revealed that corotoxigenin 3-O-glucopyranoside and calotropin interact with the cleft, so they were considered potential stabilizers of the p53-Y220C mutant comparable to the control drug 9H5, which was able to predict a position very similar to that already reported in the crystallographic structure. The ADME predicted that calotropin and desglucouzarin have more favorable pharmacokinetic parameters. Both molecules are predicted to be absorbed from the GIT. Conclusion: Calotropin of A. subulata is predicted to be a potential drug for p53-Y220C, because it binds to the cleft of the mutant and has favorable pharmacokinetic parameters. Corotoxigenin 3- O-glucopyranoside also binds to the Y220C cleft, but had less favorable pharmacokinetic parameters. These results have a future impact since calotropin could be used for the treatment of some types of cancer.

Omipalisib inspired macrocycles as dual PI3K/mTOR inhibitors.

Activation of the phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway occurs frequently in a wide range of human cancers and is a main driver of cell growth, proliferation, survival, and chemoresistance of cancer cells. Compounds targeting this pathway are under active development as anticancer therapeutics and some of them have reached advanced clinical trials or been approved by the FDA. Dual PI3K/mTOR inhibitors combine multiple therapeutic efficacies in a single molecule by inhibiting the pathway both upstream and downstream of AKT. Herein, we report our efforts on the exploration of novel small molecule macrocycles (MCXs) as dual PI3K/mTOR inhibitors. Macrocyclization is an attractive approach used in drug discovery, as the semi-rigid character of these structures could provide improved potency, selectivity and favorable pharmacokinetic properties. Importantly, this strategy allows access to new chemical space thus obtaining a better intellectual property position. A series of MCXs based on GSK-2126458, a known clinical PI3K/mTOR inhibitor is described. These molecules showed potent biochemical and cellular dual PI3K/mTOR inhibition, demonstrated strong antitumoral effects in human cancer cell lines, and displayed good drug-like properties. Among them, MCX 83 presented remarkable selectivity against a panel of 468 kinases, high invitro metabolic stability, and favorable pharmacokinetic parameters without significant CYP450 and h-ERG binding inhibition. This profile qualified this compound as a suitable candidate for future invivo PK-PD and efficacy studies in mouse cancer models.

Antibacterial Spiropyrimidinetriones with N-Linked Azole Substituents on a Benzisoxazole Scaffold Targeting DNA Gyrase.

Herein, we report spiropyrimidinetriones (SPTs) incorporating N-linked azole substituents on a benzisoxazole scaffold with improved Gram-positive antibacterial activity relative to previously described analogues. SPTs have an unusual spirocyclic architecture and represent a new antibacterial class of bacterial DNA gyrase and topoisomerase IV inhibitors. They are not cross-resistant to fluoroquinolones and other DNA gyrase/topoisomerase IV inhibitors used clinically. The activity of the SPTs was assessed for DNA gyrase inhibition, and the antibacterial activity across Gram-positive and Gram-negative pathogens with N-linked 1,2,4-triazoles substituted on the 5-position provides the most worthwhile profile. Directed nucleophilic and electrophilic chemistry was developed to vary this 5-position with carbon, nitrogen, or oxygen substituents and explore structure-activity relationships including those around a target binding model. Compounds with favorable pharmacokinetic parameters were identified, and two compounds demonstrated cidality in a mouse model of Staphylococcus aureus infection.