Pharmacodynamic Evaluation Research Articles

P1552: A PHASE 2, OPEN-LABEL STUDY TO ASSESS SAFETY, TOLERABILITY, AND CLINICAL EFFECT OF ANX005 IN PATIENTS WITH WARM AUTOIMMUNE HEMOLYTIC ANEMIA AND EVIDENCE OF COMPLEMENT ACTIVATION

Background: Autoimmune hemolytic anemia (AIHA) is caused by autoantibody destruction of red blood cells (RBCs) and is divided into warm autoimmune hemolytic anemia (wAIHA) and cold agglutinin disease. In wAIHA, which accounts for 60-70% of AIHA cases, polyclonal immunoglobulin G (IgG) antibodies cause hemolysis of RBCs at core body temperatures. However, approximately 50% of wAIHA cases are not caused by pathogenic IgG alone. The correlation between autoimmune hemolysis and presence of complement on RBCs in wAIHA patients suggests a role for the complement system in the pathogenesis of wAIHA, which can be triggered by C1q binding to autoantibodies bound to RBCs. ANX005 is a humanized IgG4 monoclonal antibody that selectively binds and inhibits C1q, blocking activation of the classical complement pathway, with the potential to inhibit complement-mediated hemolysis in wAIHA. Aims: The goal of this clinical study is to evaluate two once-weekly IV infusions of ANX005 in patients with wAIHA having evidence of complement pathway activation to understand the effect of C1q inhibition on pathway markers and objective disease parameters. Methods: This is an open-label, repeat-dose, Phase 2 study (NCT04691570) of ANX005 in patients with wAIHA and evidence of classical complement pathway activation. Up to 12 patients will be enrolled in this study and undergo a screening period of up to six weeks prior to Day 1. Patients will receive two doses of ANX005 on Days 1 and 8. Safety and pharmacokinetic (PK)/pharmacodynamic (PD) evaluations will be completed on Days 4, 15, 22, 29, 36, 43, 50, 57, and 71. Individual study duration will be up to 16 weeks, and patients will complete study participation on Day 71. The primary objective is to evaluate the safety and tolerability of ANX005. Secondary objectives include evaluating the PK and PD profile of ANX005, examining markers of classical pathway activation, and determining the impact of classical complement inhibition on hemoglobin levels and biomarkers of hemolysis through Day 71 in this subset of patients. Results: Results from the Phase 2 trial are expected by the end of 2022. Image:Summary/Conclusion: In this Phase 2 study of ANX005 in patients with wAIHA and evidence of classical complement pathway activation, patients will receive two IV doses of ANX005 one week apart with the goal of evaluating its safety, tolerability, PK/PD, and clinical effect to further understand the role of classical complement in this heterogeneous disease as a target for effective therapy.

Determination of trace metal ions in Gentiana rigescens by inductively coupled plasma-optical emission spectrometry after deep eutectic solvent-based digestion and related pharmacodynamic evaluation

A fast, simple and environmentally friendly method for the digestion of solid samples of Gentiana rigescens Franch. ex Hemsl. (G. rigescens) based on deep eutectic solvent (DES) was established, and inductively coupled plasma-optical emission spectrometry (ICP-OES) was used to quantify Ni, Zn, Co, Cr and Cu in DES digestion solution. Under optimized conditions, limits of detection (LOD) and limits of quantification (LOQ) ranged from 0.4 to 2.5 and 1.2–8.2 μg g-1, respectively. The intra-day and inter-day precision were carried out by relative standard deviation (RSD) ranged from 0.8% to 4.9% and 0.6%–1.4%, and the spiked recoveries ranged from 90.6% to 111.9%, respectively. The results of quantitative analysis by the developed method were in good agreement with those of microwave digestion. At the same time, the contents of the metal ions in the G. rigescens decoction liquid and freeze-dried powder solution of the decoction liquid of G. rigescens (crude extract) were determined by ICP-OES. The results showed that the contents of Ni, Zn, Co and Cu in the decoction liquid and crude extract were significantly lower than the contents in DES digestion liquid, and Cr was not detected. Then, the oxidative damage model of LO2 cells induced by H2O2 was established. The protective effect of crude extract of G. rigescens on damaged liver cells and the effect of metal ions with the same contents of decoction liquid on liver protection of G. rigescens were investigated for the first time. The results show that H2O2 could induce the decrease of LO2 cell viability and damage the cell morphology. GPS and crude extract could inhibit H2O2-induced liver injury by adjusting the antioxidant enzyme system. Metal ions corresponding to the content of the decoction liquid may weaken the hepatoprotective effect of GPS or crude extract by regulating the antioxidant enzyme system.

Abstract CT140: ANV419, an IL-2R-beta-gamma targeted antibody-IL-2 fusion protein, induces selective effector cell proliferation in patients with progressed cancer

Abstract Developing a safe and effective non-alpha IL-2R agonist to enhance the numbers and activation status of immune effector cells for the treatment of cancer has remained an elusive goal since the initial approval of Interleukin-2 (IL-2). ANV419 comprises an antibody specific for the IL-2Rα-binding domain of IL-2 fused to native hIL-2 and functions as a potent, highly selective, IL-2Rβγ binding agonist. ANV419 has shown high effector selectivity and a favorable safety profile in preclinical testing, including in non-human primates, and is currently being investigated in an ongoing phase I/II dose finding study in multiple tumor types (ANV419-001). Here we present data from the single patient cohort and the initial 3+3 cohort dose escalation. Data cut-off was December 22nd, 2021. Ten patients in five dose cohorts. Patients had progressed melanoma (cutaneous (n=3), uveal (n=2), mucosal (n=1), choroidal (n=1)), renal cell carcinoma(n=1), hepatocellular carcinoma (n=1) and colorectal cancer(n=1) received Q2W doses of ANV419 of 3mcg/kg (n=1), 6mcg/kg (n=1), 12mcg/kg (n=1), 24mcg/kg (n=4) and 48mcg/kg (n=3) body weight without immunosuppressive premedication as a 15-minute intravenous infusion. Patients received a mean of 4 cycles. Minimal follow up of patients completing the dose limiting toxicity (DLT) period is 2 cycles. All patients experienced mild chills (Grade 1) with or without low-grade fever (Grade 1) hours after drug administration. These resolved with antipyretic treatment within hours. There were two grade 2 AEs in two patients related to ANV419. One patient developed Grade 2 CRS (hypotension grade 2 with fever (Grade 1) and chills (Grade 1) that resolved with 500ml intravenous fluid. One patient experienced transient, self-limiting Grade 2 CRS. No drug related Adverse Events >Grade 2 and no DLTs were observed. One patient in the 24 mcg/kg cohort was non evaluable and was subsequently replaced. Pharmacodynamic evaluation on day 4 post-dosing, showed a dose dependent increase of Ki-67 positivity in CD8 T cells (2%, 14%, 37%, 62%, 62% vs. baseline mean (BLM) 2%)) and NK cells (30%, 62%, 75%, 85%, 80% vs BLM 6%) but not CD4 regulatory T cells (4%, 13%, 25%, 16%, 19% vs. BLM 5%) at 3, 6, 12, 24 and 48 mcg/kg doses respectively. Pharmacokinetic data show a dose proportional increase of serum concentration of ANV419. Both PK and PD were conserved over multiple cycles. Four patients continue to receive ANV419. Four patients underwent more than one follow-up imaging, all of which showed stable disease. Updated patient data will be presented during the meeting. ANV419 is very well tolerated and induces a high degree of proliferation in CD8 T cells and NK cells but not Tregs. ANV419-001 will further evaluate the safety and efficacy of ANV419 alone and in combination with other immunotherapy drugs. Citation Format: Elena Garralda, Alonso Guzman, Juanita Lopez, Vicky Sanchez-Perez, Heinz Läubli, Emiliano Calvo, Christoph Huber, Nicole Egli, Aswathy Nair, Julie Mouton, Kirsten Richter, Carlo Lanza, Sangeeta Jethwa, Silvio Costanzo, Christoph Bucher. ANV419, an IL-2R-beta-gamma targeted antibody-IL-2 fusion protein, induces selective effector cell proliferation in patients with progressed cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT140.

The Traditional Mongolian Medicine Qiqirigan-8 Effects on Lipid Metabolism and Inflammation in Obesity: Pharmacodynamic Evaluation and Relevant Metabolites.

Objective: Traditional Mongolian Medicine Qiqirigan-8 (MMQ-8) is a Chinese botanical drug with effective pharmacological properties in obesity. However, the pharmacological mechanism of MMQ-8 remains unclear. This study aimed to determine the active metabolites of MMQ-8 and its therapeutic effects on lipid metabolism and inflammation. Methods: The active metabolites of MMQ-8 were identified by ultrahigh-performance liquid chromatograph Q extractive mass spectrometry (UHPLC-QE-MS) assay and network analysis. An obesity rat model induced by high-fat diet was used in the study. Serum levels of lipids and inflammatory factors were detected using biochemical analysis and enzyme-linked immunosorbent assay (ELISA). Pathological analysis of liver tissues and arteries was conducted with hematoxylin and eosin (H&E) staining and immunohistochemistry. Protein expression of the tumor necrosis factor (TNF) signaling pathway was investigated by Western-blot. Simultaneously, bone marrow cells were used for RNA sequencing and relevant results were validated by cell culture and quantitative real-time polymerase chain reaction (RT-qPCR). Results: We identified 69 active metabolites and 551 target genes of MMQ-8. Of these, there are 65 active metabolites and 225 target genes closely related to obesity and inflammation. In vivo, we observed that MMQ-8 had general decreasing effects on body weight, white adipose tissue weight, and serum lipids. MMQ-8 treatment notably decreased the liver function markers and hepatic steatosis, and significantly decreased inflammation. In serum, it notably decreased TNF-α, interleukin (IL)-6, and inducible nitric oxide synthase (INOS), while elevating IL-10 levels. MMQ-8 treatment also significantly inhibited proteins phosphorylation of nuclear factor-kappa B inhibitor alpha (IκBα), mitogen-activated protein kinase (p38), extracellular regulated kinase 1/2(ERK1/2), and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), and decreased vascular endothelium damage and macrophage infiltration and polarization to M1. These findings coincide with the RNA-sequencing data of bone marrow cells and results of in vitro experiments. Conclusion: We determined the pharmacological actions and relevant metabolites of MMQ-8 in obesity for the first time. Our study revealed MMQ-8 can optimize lipid metabolism and reduce chronic inflammation in obesity. However, more in-depth research is needed, for example, to understand the principle of compound compatibility and the inhibition effects on hepatic steatosis, T cell differentiation, and inflammatory signal transduction.

Abstract 1996: Intravenous administration of the small molecule STING agonist CRD5500 elicits potent anti-tumor immune responses in cold tumors

Abstract Background: Innate immune signaling mediated through STING (Stimulator of Interferon Genes) generates a Type I interferon (Type 1 IFN) signal that increases T cell infiltration into cold or non-inflamed tumors leading to significant regression1. CRD5500 is a small molecule STING agonist that has demonstrated excellent systemic tolerability in primate GLP toxicology studies and is scheduled for IND filing with the US FDA in the first half of 2022. The compound binds to STING at a unique location that is outside the dimeric cleft that is the natural ligand binding site2. While this first-in class agent cross-reacts with cynomolgus monkey STING and activates all five major variants of human STING with similar potency, it does not cross-react with rodent STING. Here we demonstrate the potent anti-tumor activity of CRD5500 administered intravenously in a range of immunologically cold murine tumors implanted in human STING knock-in mice. Methods: The functional potency of STING across species was evaluated in STING over-expressing HEK293T cells and PBMCs. Human STING KI mice (Genoway) were used to monitor anti-tumor effects of CRD5500 dosed IV or IT against the following tumors: B16F10 (melanoma), PANO2 (pancreatic), C1498 (acute myeloid leukemia) and LL2 (lung). Intravenous pharmacokinetic and pharmacodynamic evaluation was carried out in cynomolgus monkeys. Results: CRD5500’s activated the different variants of human STING with EC50 values that ranged from 10-70 nM in an pIRF3 reporter assay. Treatment of hSTING transfected cells, human tumor cell lines or hPBMC with CRD5500 led to dose dependent activation of STING. Further, CRD5500 treatment of human DCs and PBMCs led to the induction of inflammatory cytokines such as IFNβ and TNFα. Intravenous administration of CRD5500 in human STING knock-in mice caused tumor regression in several cold tumor models such as B16F10, PANO2, LL2, C1498. Further, CRD5500 demonstrated the abscopal effect in B16F10 tumors when administered via intratumoral route. The compound was well tolerated at high doses in the primate GLP study when administered intravenously and caused dose and exposure dependent increases in CXCL10. Conclusion: The ability of CRD5500 to generate impressive anti-tumor immune responses in cold tumors as a single agent coupled with its excellent IV safety profile in non-human primates make it well suited for FIH investigations planned for mid-2022 under a US FDA IND.

Abstract CT189: PRTX007, an optimized TLR7 agonist for systemic immunotherapy of cancers: Interim analysis of phase I study in healthy volunteers

Abstract Background. Toll-like receptor 7 (TLR7) agonists have long been recognized as potential systemic anti-cancer immunotherapy agents. However, clinical development has been limited by complex target-mediated pharmacology including those associated with elevated levels of proinflammatory factors, which also limit the ability to combine with immune checkpoint inhibitors (CPI). PRTX007 is an orally administered prodrug of PRX034, a novel TLR7 agonist that elicits IFN-mediated immune induction without inducing inflammation via the NF-κβ pathway. QOD dosing in primates maintains a stable immune response without immune exhaustion or toxicity. Efficacy, safety, and compatibility with immune CPI were demonstrated in a CT26 syngeneic rodent tumor model. Methods. We conducted a phase 1, single-center, prospective, randomized, double-blind placebo-controlled study of 8 single-ascending dose (SAD) and 4 multiple-ascending dose (MAD) cohorts of PRTX007 administered orally to healthy adult participants. Primary objectives were safety and tolerability. Secondary objectives were evaluation of pharmacokinetics (PK) and pharmacodynamics. This interim analysis focuses on the 8 SAD (50-600 mg) and 2 MAD (300-400 mg) cohorts, with 64 of the 84 participants in the study receiving drug. Results. Treatment-related adverse events include non-dose‒related mild headache, and minor dose-related increases in ALT (<2X ULN) that rapidly resolved. The PKs of PRTX007 and PRX034 are well-behaved eg, exposure increasing proportionally with PRTX007 dose. Consistent with studies in human cells in vitro and non-human primates in vivo, oral administration of PRTX007 elicits systemic TLR7-mediated immune induction without engaging NF-κβ─mediated biosynthesis of IL-6, TNFα and IL-1β in humans. A single dose of PRTX007 (300-600 mg) elicits coordinated expression of IFN-stimulated genes (ISGs) in blood without quantifiable increases in circulating IFNs. At 500 and 600 mg doses, IP-10, IL-1RA, MCP-1 and TRAIL but not IL-6, TNFα or IL-1β increase in plasma (maximal response = 4020, 1460, 650 and 360 pg/ml, respectively). When PRTX007 is administered for 2 weeks on a QOD schedule at 400 mg/dose, the degree of ISG expression progressively increases when compared to the first-dose response, (eg, ISG15 increases 2.1-fold [geometric mean] following Dose 1 vs pretreatment baseline, rising to 12.2-fold following Dose 7). This is accompanied by modest activation of circulating NK, B, and CD4+ and CD8+ T cells as measured by cell-surface markers. IL-6, TNFα and IL-1β remain unchanged from pretreatment levels. Conclusion. At the interim analysis, PRTX007 demonstrated a favorable safety profile when administered orally to all tested SAD and MAD cohorts. Dose-dependent systemic exposure was observed, as well as activation of the innate immune response, without production of proinflammatory factors. Citation Format: Charlotte Lemech, Christopher Argent, Curtis Scribner, Richard Daniels, James Richard Appleman. PRTX007, an optimized TLR7 agonist for systemic immunotherapy of cancers: Interim analysis of phase I study in healthy volunteers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT189.

Abstract CT209: A first-in-human phase 1 trial of IO-108, an antagonist antibody targeting LILRB2 (ILT4), as monotherapy and in combination with pembrolizumab in adult patients with advanced relapsed or refractory solid tumors (NCT05054348)

Abstract Cancer immunotherapy has entered the mainstream with approval of T-cell checkpoint inhibitors. However, most patients with advanced solid tumors do not derive benefits, or relapse after T-cell checkpoint blockade. Myeloid checkpoint inhibition is a new approach to cancer immunotherapy. LILRB2 is primarily expressed by myeloid cells and its expression in tumors is associated with high macrophage infiltration. Several LILRB2 ligands (HLA-G, ANGPTL2, and SEMA4A) are known to contribute to the immune suppressive microenvironment of solid tumors. Blockade of the LILRB2 pathway has the potential to reactivate or enhance anti-tumor T cell immune responses. IO-108 is a IgG4 monoclonal antibody that specifically binds LILRB2 to block ligands interaction and activation of LILRB2. In vitro, IO-108 treatment of primary immune cells results increased pro-inflammatory responses and an enhanced antigen presenting cell phenotypes. A Good Laboratory Practice repeat-dose, 15-day toxicology study in Cynomolgus monkeys at 0 (control), 1, 10, or 100 mg/kg/dose administered intravenously once weekly for a total of 3 doses showed that IO-108 was well-tolerated at all dose levels, with only non-statistically significant reduction of thyroid glands weight. No-observed-adverse-effect-level (NOAEL) of 100 mg/kg provides a sufficient safety margin for the IO-108 starting dose of 60 mg, which was derived using a MABEL (minimum anticipated biological effect level) approach. This clinical trial is a first-in-human, Phase 1, multicenter, open-label, dose-escalation, safety, pharmacokinetic (PK), and pharmacodynamic evaluation of intravenously administered IO-108, both as monotherapy and in combination with pembrolizumab, in adult patients with solid tumors that have failed standard of care therapies (NCT05054348). It is estimated that up to 36 patients will be enrolled in the study. IO-108 will be administered every 21 days, with a dose-limiting toxicity (DLT) evaluation period of 21 days. Patients will be enrolled into sequential cohorts and treated with increasing doses of IO-108 using mTPI (modified Toxicity Probability Interval) method. Safety, PK, and clinical activity will be evaluated on an ongoing basis. The primary objective of the study is to assess safety and tolerability at increasing dose levels of IO-108 in successive cohorts of adult patients (treated with or without with pembrolizumab) with advanced relapsed or refractory solid tumors, to estimate the maximal tolerated dose (MTD) or maximum administered dose (MAD) and select the recommended phase 2 dose (RP2D). Secondary objectives include characterizing PK, immunogenicity, and preliminary anti-tumor activity. Biomarker evaluation will include changes in myeloid cell markers and T-cells, LILRB2 expression level and receptor occupancy. Statistical analyses will be primarily descriptive in nature. Tabulations will be produced for appropriate disposition, demographic, baseline disease characteristics, safety, PK, pharmacodynamic, and clinical activity parameters. Response to treatment as assessed by RECIST v1.1 will be tabulated. To date, five patients have been dosed without DLT. Citation Format: John Powderly, Manish Patel, Paul Woodard, Luke Chung, Hongyu Tian, Elizabeth Wieland, Kyu Hong, Maria Jose Costa, X. Charlene Liao, Matthew Taylor. A first-in-human phase 1 trial of IO-108, an antagonist antibody targeting LILRB2 (ILT4), as monotherapy and in combination with pembrolizumab in adult patients with advanced relapsed or refractory solid tumors (NCT05054348) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT209.

Abstract 1141: Pharmacokinetic and pharmacodynamic evaluation of human tumor xenograft models treated upon administration of trastuzumab deruxtecan

Abstract Introduction: Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate comprised of an anti-HER2 antibody, a cleavable tetrapeptide-based linker, and a cytotoxic topoisomerase I inhibitor approved for the treatment of HER2 positive metastatic breast and gastric cancer. T-DXd has demonstrated antitumor activity in both HER2+ and HER2-low patient populations. Methods: To establish exposure profiles of T-DXd and link with tumor biomarker changes, we administered a single IV dose of T-DXd at 10 mg/kg in human tumor xenograft models representing HER2-positive (NCI-N87; nude) and Her2-low (Capan-1; NOD-SCID) and collected tumor and plasma from 6 h to 336 h post dose. We measured tumor volume in addition to total ADC, total antibody, and free payload in the plasma and assessed biomarkers related to DNA damage in the tumor by western blot (WB) and immunohistochemistry (IHC). Results: In HER2+ NCI-N87 tumor-bearing mice, T-DXd plasma AUC was 342.6ug/ml*day and T1/2 was 3.5 days, while in the HER2-low Capan-1 tumor-bearing mice, T-DXd plasma AUC was 297.2ug/ml*day and T1/2 was 1.4 days. Plasma exposures of free payload (DXd) were less than 1 ng/mL. Both models responded to T-DXd, demonstrating regression over the 14 day study (T/C =-6.08%, NCI-N87 and -96.1%, Capan-1). In NCI-N87, we observed rapid and sustained increases in gamma H2AX (gH2AX), with a 3.5-fold increase in % positive staining by IHC (H-score p<0.001) with gH2AX foci as early as 24h post treatment, and sustained out to 96h. Western blot analysis and quantification of gH2AX revealed a 4.3-fold increase at 48h (p<0.0001), which was sustained out to 96h. Further, we observed significant increases in pRAD50 at 24h (3.6-fold increase by IHC, H-score p<0.001) which was sustained out to 96h. In Capan-1, we observed more diffuse staining of gH2AX and non-significant 1.4-fold increase in gH2AX at 24h. pRAD50 increases were delayed in the Capan-1 model with a 2.8-fold increase observed at 48h and sustained out to 168h post treatment. Conclusions: Plasma exposure of T-DXd in NCI-N87 tumor bearing mice was prolonged compared to Capan-1, possibly due to mouse strain differences. The increased systemic exposure resulted in more rapid and sustained DNA damage as measured by gH2AX and pRAD50 in the NCI-N87 tumor compared to Capan-1. This profile suggests exploration of combinations with DNA damage response inhibitors to inform design of dose and schedule of combination therapy may be warranted. Citation Format: Theresa Proia, Jelena Urosevic, Christina Vasalou, Rebecca Sargeant, Matthew Griffin, Jiaqi Yuan, Anton I. Rosenbaum, Jerome Mettetal. Pharmacokinetic and pharmacodynamic evaluation of human tumor xenograft models treated upon administration of trastuzumab deruxtecan [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1141.

Phase I study of HFB200301, a first-in-class TNFR2 agonist monoclonal antibody in patients with solid tumors selected via Drug Intelligent Science (DIS).

TPS2670 Background: Tumor necrosis factor receptor-2 (TNFR2) is expressed on effector CD8+ T cells, CD4+ T cells, T regulatory cells, natural killer cells, and myeloid cells. Targeting TNFR2 is anticipated to yield effective anti-tumor immunity by stimulating T-cell and NK-cell activation and proliferation in the tumor microenvironment. HFB200301 is a first-in-class anti-TNFR2 agonistic monoclonal antibody that triggers both innate and adaptive immune stimulation by binding to a specific epitope on TNFR2. HFB200301 has demonstrated dose-dependent anti-tumor activity in human TNFR2 knock-in mice bearing MC38 and Hepa1-6 syngeneic tumors. Methods: HFB200301 is being evaluated in a first-in-human, open-label, multi-center, dose escalation and expansion study in adult patients with advanced solid tumors. A single-cell immune profiling platform, DIS, was deployed to identify unique tumor-infiltrating T cell signatures that could help optimize patient selection for HFB200301 treatment. It is hypothesized that the presence of an effector T cell subpopulation that express both TNFR2 and CD8A in solid tumors may represent a tumor microenvironment favorable to TNFR2 agonism. The following cancer indications have been identified based on the prevalence of a TNFR2 high/CD8 high signature: Epstein-Barr Virus positive (EBV+) gastric cancer, clear cell renal cell carcinoma (ccRCC), cutaneous melanoma, testicular germ cell tumor (TGCT), soft tissue sarcoma (STS), and PD-L1+ cancers: cervical cancer, pleural mesothelioma, lung adenocarcinoma, and head and neck squamous cell carcinoma (HNSCC). The escalation portion of the study explores increasing doses in cohorts of up to six patients, utilizing mTPI-2 design to determine recommended dose(s) for expansion (RDE(s)). Based on pharmacokinetic modeling to maximize HFB200301 activity, 60-minute intravenous infusions of HFB200301 are administered every 4 weeks. Once RDE(s) is determined, expansion into three indication-specific cohorts is planned to determine the recommended phase 2 dose (RP2D). Key eligibility criteria include histologically documented advanced or metastatic solid tumors in the above listed indications. Patient enrollment opened in February 2022 in the USA, with plans for additional clinical sites in Spain and China. The primary objective is to identify the RDE, characterize safety and tolerability of HFB200301, and determine RP2D. Secondary objectives include pharmacokinetic parameters, preliminary evidence of anti-tumor efficacy (e.g., ORR, DCR, DOR) and pharmacodynamic evaluation (e.g., T cell subsets) in the blood and in the tumor. Furthermore, a potential predictive biomarker signature derived based on the DIS single-cell immune profiling approach will be investigated retrospectively. Clinical trial information: NCT05238883.

A phase I/II study of ANV419, a selective IL-2R-beta-gamma targeted antibody-IL-2 fusion protein, in patients with advanced solid tumors.

e21552 Background: IL-2R agonists that are well tolerated and can selectively enhance immune activation may improve outcomes of patients with cancer. ANV419 is a potent and highly selective IL-2Rβγ binding agonist, consisting of an antibody specific for the IL-2Rα-binding domain of IL-2, fused to native hIL-2. It is currently being investigated in a phase I/II dose finding study in patients with relapsed/refractory advanced solid tumors (ANV419-001). The primary objective of ANV419-001 is to describe the safety and tolerability of ANV419. Methods: ANV419 is administered intravenously over 15 minutes every 2 weeks, without premedication. Thirteen patients with melanoma (cutaneous (n = 3), uveal (n = 2), mucosal (n = 2), choroidal (n = 1)), renal cell carcinoma (n = 1), hepatocellular carcinoma (n = 1), colorectal cancer (n = 1), esophageal adenocarcinoma (n = 1) and adenoid cystic carcinoma (n = 1) have been dosed in six cohorts. Patients received 3mcg/kg (n = 1), 6mcg/kg (n = 1), 12mcg/kg (n = 1), 24mcg/kg (n = 4), 48mcg/kg (n = 3) 72mcg/kg (n = 3) and 108 mcg/kg (ongoing) of ANV419. Results: ANV419 is well tolerated, all related AEs are Grade 1 or Grade 2 and no DLTs have been observed. Most patients experienced chills (G1), with or without low-grade fever (G1), 2-4 hours after post- infusion, which resolved with antipyretic treatment. Two G2 AEs related to ANV419 have been reported in two patients. One patient was reported to have G2 Cytokine Release Syndrome (hypotension (G2), fever (G1), chills (G1)) and one patient experienced transient, self-limiting G2 elevation of liver function tests. Four Serious Adverse Events were reported in three patients (urinary tract infection, lethargy, thoracic pain and abdominal pain), none of which were considered related to ANV419. Pharmacodynamic evaluation on day 4 post-dosing, showed an effector cell selective, dose dependent increase of Ki-67 positive CD8 T cells (2%, 14%, 37%, 62%, 62%, vs. baseline mean (BLM) 2%) and NK cells (30%, 62%, 75%, 85%, 80%, vs BLM 6%) with a dose independent frequency of Ki67+ Tregs ranging from 4% to 25% (BLM 7%) at 3, 6, 12, 24 and 48 mcg/kg doses respectively. At 72mcg/kg mean CD8 T cell and NK proliferation was 70% and 51% respectively, while the mean Treg proliferation increased to 48%. Pharmacokinetic data (including patients treated with up to 24 mcg/kg ANV419) show a dose proportional increase of the ANV419 plasma concentration. The estimated half-life at the 24mcg/kg dose is 17.6 hrs. Four patients continue to receive ANV419. Of the 11 patients who received at least two cycles of ANV419, 4 were assessed to have stable disease. One patient progressed after 24 weeks of confirmed stable disease. Conclusions: Overall, ANV419 is well tolerated and selectively induces expansion and proliferation of CD8 T cells and NK cells, but not Tregs up to a dose of at least 48mcg/kg. Updated data will be shared during the meeting. Clinical trial information: NCT04855929.

Trial in progress: Phase I study of SY-5609, a potent, selective CDK7 inhibitor, with initial expansion in adults with metastatic pancreatic cancer.

TPS4180 Background: SY-5609 is an oral, selective, potent CDK7 inhibitor that targets two fundamental processes in cancer: transcription and cell cycle control. Early results from the Phase 1 dose escalation portion in patients (pts) with advanced solid tumors reported improved tolerability of the intermittent 7 days on followed by 7 days off (7/7) schedule with ongoing dose escalation beyond the continuous daily dosing maximum tolerated dose. Single-agent clinical activity was demonstrated with durable stable disease, target lesion regressions, and reduction in tumor markers observed in multiple tumor types, notably in pancreatic cancer with a disease control rate (DCR) of 38.5% (Sharma 2021). Pancreatic ductal adenocarcinoma (PDAC) has a 5-year survival rate of 11% (ACS Cancer Facts and figures, 2022) with limited treatment options and therefore, is a disease in need of novel effective therapies. Oncogenic KRAS mutations are prevalent in PDAC. Mutant KRAS is a potent stimulator of mitogenic MAPK signaling and downstream transcriptional programs for cell proliferation. Preclinical studies have shown that CDK7 inhibition via SY-5609 inhibits tumor growth in KRAS mutant PDAC xenograft models, in many cases leading to regressions. SY-5609 also potentiates gemcitabine (gem) activity in PDAC cells in vitro and in xenografts in vivo (Henry 2021). Therefore, combining SY-5609 with gem +/- nab-paclitaxel (nab-pac) offers a potential new treatment strategy for metastatic PDAC (mPDAC). The expansion portion of this Phase 1 study will evaluate SY-5609 in combination with gem +/- nab-pac in mPDAC pts. Gem +/- nab-pac will be administered on a biweekly schedule as it has shown better tolerability and similar clinical activity compared to the standard of care (SOC) administration schedule (Rehman 2020). Methods: This is an ongoing Phase 1, multi-center study in select solid tumors, amended to open expansion cohorts for mPDAC and expected to enroll approximately 80 mPDAC pts who have progressed on SOC treatments. Objectives of the expansion cohorts include evaluation of safety and efficacy of SY-5609 in combination with gem +/- nab-pac. Key objectives of the two parallel safety lead-in cohorts 1) SY-5609 + gem and 2) SY-5609 + gem + nab-pac are safety and determination of the recommended combination dose of the doublet and triplet for subsequent cohort expansions using a 3+3 escalation design. Key objectives of expansion cohorts are to describe efficacy, defined by progression-free survival, overall response rate, and DCR. Additional objectives include evaluation of pharmacokinetics and pharmacodynamics of SY-5609 in combination with gem +/- nab-pac. SY-5609 will be administered orally once daily on a 7/7 regimen and gem +/- nab-pac will be administered intravenously, in a 4-week cycle. The expansion portion is now open to enrollment. Clinical trial information: NCT04247126.

Pharmacokinetic and pharmacodynamic activity evaluation of MAK683, a selective oral embryonic ectoderm development (EED) inhibitor, in adults with advanced malignancies in a first-in-human study.

3083 Background: Polycomb Repressive Complex 2 (PRC2) regulates transcription via trimethylation of histone H3 at lysine 27 (H3K27me3). Its dysregulation and over-expression are associated with tumorigenesis in several conditions. MAK683 is a potent oral inhibitor of PRC2 activation, allosterically targeting the EED–H3K27me3 binding site. Methods: NCT02900651 is an ongoing first-in-human dose-escalation study of MAK683 in adults with advanced malignancies. MAK683 was administered fasted once (QD) or twice daily (BID) on a continuous schedule in 28-day treatment cycles. The pharmacokinetic (PK) profile of MAK683 was assessed in sequential blood samples on Days 1, 8 and/or 15 of Cycles 1–6. MAK683 pharmacodynamic activity in Cycle 1, measured by change in H3K27me3, was evaluated in peripheral blood monocytes on Days 1, 8, and 15 by flow cytometry and in tumor biopsies at baseline and Day 15 by H-score. Results: As of Aug 30, 2021, 125 patients had received MAK683 at doses of 10–800 mg QD or 60–450 mg BID. MAK683 was well absorbed with a median Tmax of ̃1-4 hours across cohorts. PK exposure (Cmax, AUC) increased generally with dose over the entire dose range with no major deviation from dose proportionality, taking into account the sample size and PK variability. Apparent terminal half-life (geometric mean) was 2.5–6.6 hours across cohorts and constant over time. MAK683 accumulation of ̃0.9-2.2-fold (QD) or ̃1.3-2.0-fold (BID) was seen with repeat dosing. Peripheral monocytes showed substantial on-treatment reductions from baseline in the H3K27me3/H3 ratio across doses. Maximum percentage reduction was proportional to cumulative MAK683 AUC, with a trend towards greater reductions at higher baseline H3K27me3. H3K27me3 H-score reductions from baseline > 40 were observed in 7/10 patients with diffuse large B-cell lymphoma (n = 4) or epithelioid sarcoma (n = 6) and paired baseline–Day 15 biopsies. RNA-seq characterization of biopsy samples is ongoing. Conclusions: MAK683 has a PK profile supportive of QD or BID dosing in patients with advanced malignancies. Analysis of H3K27me3 in blood monocytes and tumor biopsy confirm the in vivo pharmacodynamic activity of MAK683. Clinical trial information: NCT02900651.

Safety, pharmacodynamic, and clinical response evaluation of nilotinib and paclitaxel in adults with refractory solid tumors.

3026 Background: The combination of the BCR-Abl kinase inhibitor nilotinib and the anti-tubulin agent paclitaxel was identified in the NCI-ALMANAC study to have greater-than-additive activity in the NCI-60 cell line panel and greater-than-single-agent antitumor activity in xenograft models, in which this combination induces tumor epithelial-mesenchymal transition (EMT). A phase 1 study was initiated to establish the safety, tolerability, and recommended phase 2 dose (RP2D) of this combination in patients (pts) with advanced solid tumors and to examine the pharmacokinetic (PK) and pharmacodynamic (PD) effects of the combination to understand the mechanism of action (NCT02379416). The dose escalation phase established the RP2D as 300 mg oral nilotinib twice daily and 80 mg/m2 intravenous paclitaxel on days (D) 1, 8, and 15 of each 28-day cycle. Here, we report the safety, preliminary PD, and efficacy data for this combination. Methods: Nilotinib and paclitaxel were administered as noted above, with a 1-day (escalation cohort) or 2-day (expansion cohort) paclitaxel-only run-in during the first cycle to enable comparison of the PK and PD effects of the combination vs. single-agent paclitaxel. Paired biopsies to assess tumor molecular response were collected from expansion cohort pts at baseline, cycle (C) 1 D2, and C1D28, with an optional biopsy at progression; accrual continued until ≥ 12 sufficient-quality paired biopsies were obtained. Blood specimens to assess molecular responses in circulating tumor cells (CTCs) were obtained at several timepoints during C1 and longitudinally every cycle thereafter. EMT biomarkers were measured in tumor and CTC specimens using quantitative immunofluorescence microscopy assays. Results: A total of 44 pts were enrolled. Three pts had partial responses (PR), and 1 had an unconfirmed PR (9%); 23 pts (52%) had a best response of stable disease (SD), including 7 pts on study for ≥ 10 cycles. The most common grade (Gr) 3-4 treatment-related adverse events were hematologic and hypophosphatemia. No pts experienced Gr ≥ 3 peripheral neuropathy. The median time on treatment was 67 days. Two pts with granulosa cell ovarian carcinoma had durable responses, completing 74+ and 64 cycles. Multiple patient biopsies and corresponding CTC specimens exhibited treatment-induced EMT. Longitudinal analysis of CTC EMT phenotypes in the 2 pts with extended PR revealed a substantial increase in mesenchymal-like CTCs prior to progression for the pt on study for 64 cycles; such increases were not observed in the pt still on study after 74+ cycles. Further PD analyses are ongoing. Conclusions: The combination of nilotinib and paclitaxel demonstrates promising disease control with durable response in select patients. Tumor PD analyses to discover the underlying pharmacology of this active regimen are ongoing. Funded by NCI Contract No. HHSN261201500003I. Clinical trial information: NCT02379416.

Efficacy proof-of-concept from a phase 1 study of a novel therapeutic peptide, ST101, targeting the oncogenic transcription factor C/EBPβ in patients with refractory solid tumors.

3014 Background: The oncogenic transcription factor CCAAT/enhancer-binding protein β (C/EBPβ) promotes tumor survival and proliferation and inhibits differentiation. ST101 is a peptide antagonist of C/EBPβ, with anti-tumor activity in prostate cancer (PC), glioblastoma (GBM), breast cancer (BC), melanoma, and other pre-clinical models. Methods: This phase 1 study enrolled patients (pts) with refractory solid tumors with varying histologies. The primary objective was to evaluate safety/tolerability of ST101 and to determine the recommended phase 2 dose (RP2D). Secondary and exploratory objectives included pharmacokinetics (PK), preliminary efficacy (RECIST 1.1), and pharmacodynamic (PD) evaluation. The study used a 3+3 dose-escalation design, with once-weekly IV infusion dosing of ST101 at 0.5, 1, 2, 4, 6, 9 mg/kg or a flat dose of 500 mg. Results: Enrollment in phase 1 was completed in November 2021 with a total of 25 pts with multi-metastatic disease that were refractory to standard therapy. As of February 15, 2022, five pts remain on study with a median treatment duration of 27 weeks’ (16-77). There were no DLTs, dose modifications, or serious adverse events (SAEs) related to ST101. The only AEs of note were G1-2 histaminergic infusion-related reactions (IRRs), largely pruritis and urticaria, managed with antihistamines, montelukast, and interruption/slowing of infusion. IRRs affected 93% of pts on the first dose at ≥4mg/kg and led to prolongation of infusion time. Intensity and frequency of IRRs decrease with repeat dosing. No other AEs were consistently reported. There was no evidence of accumulation upon continued exposure of ST101 and no anti-drug antibodies. Tumor immunohistochemistry showed dose-proportionate staining for ST101 and decreased tumor proliferation in several pts represented by decreased Ki67 expression. Population PK analysis supported flat dosing in phase 2. Five pts continue on treatment with one confirmed partial response in a patient with cutaneous melanoma lasting >42 weeks and four pts with ongoing stable disease. Conclusions: ST101 demonstrated safety at all doses explored and evidence of efficacy across dose levels, particularly higher doses and in pts with melanoma. PK and PD support a dose relationship for efficacy and selection of 500 mg as the RP2D. Pts are now enrolling in phase 2 cohorts to assess response in cutaneous melanoma, GBM, castrate-resistant PC, and HR+ BC. Clinical trial information: NCT04478279. [Table: see text]

Pharmacodynamics evaluation of Eggplant wastes formulated as lyophilized tablets in an attempt for preparation of a bioactive natural antidiabetic dosage form

Pharmacodynamics evaluation of Eggplant wastes formulated as lyophilized tablets in an attempt for preparation of a bioactive natural antidiabetic dosage form

Discovery and pharmacodynamic evaluation of the novel butene lactone derivative M355 against influenza A virus in vitro and in vivo.

A new series of butene lactone derivatives were designed according to an influenza neuraminidase target and their antiviral activities against H1N1 infection of Madin-Darby canine kidney cells were evaluated. Among them, a compound that was given the name M355 was identified as the most potent against H1N1 (EC50 = 14.7 μM) with low toxicity (CC50 = 538.13 μM). It also visibly reduced the virus-induced cytopathic effect. Time-of-addition analysis indicated that H1N1 was mostly suppressed by M355 at the late stage of its infectious cycle. M355 inhibited neuraminidase in a dose-dependent fashion to a similar extent as oseltamivir, which was also indicated by a computer modeling experiment. In a mouse model, lung lesions and virus load were reduced and the expression of nucleoprotein was moderated by M355. The enzyme-linked immunosorbent assay and quantitative real-time polymerase chain reaction analyses revealed that the levels of interferon-γ, interferon regulatory factor-3, Toll-like receptor-3, tumor necrosis factor-α,interleukin (IL)-1β, IL-6, and IL-8 were downregulated in the M355-treated groups, whereas the levels of IL-10 and IL-13 were upregulated. Similarly, IgG was found to be increased in infected mice plasma. These results demonstrate that M355 inhibit the expression of H1N1 in both cellular and animal models. Thus, M355 has the potential to be effective in the treatment of influenza A virus infection.

A Candidate Drug Screen Strategy: The Discovery of Oroxylin A in Scutellariae Radix Against Sepsis via the Correlation Analysis Between Plant Metabolomics and Pharmacodynamics.

Sepsis is an acute systemic infectious disease with high mortality, which urgently needs more effective treatment. Scutellariae radix (SR), a commonly used traditional Chinese medicine (TCM) for clearing heat and detoxification, contains rich natural products possessing anti-inflammatory activity. In previous studies, it was found that the anti-inflammatory activities of SR extracts from different ecological conditions varied wildly. Based on this, in the present study, a screening strategy of antisepsis active components from SR based on correlation analysis between plant metabolomics and pharmacodynamics was established, and the mechanism was explored. First of all, a mass spectrum database of SR (above 240 components) was established to lay the foundation for the identification of plant metabolomics by liquid chromatography tandem mass spectrometry (LC–MS/MS). Through the correlation analysis between plant metabolomics and anti-inflammatory activity of SR from different ecology regions, 10 potential components with high correlation coefficients were preliminarily screened out. After the evaluation of anti-inflammatory activity and toxicity at the cellular level, the pharmacodynamic evaluation in vivo found that oroxylin A had the potentiality of antisepsis both in LPS- and CLP-induced endotoxemia mice. Network pharmacology and Western blot (WB) results indicated that oroxylin A significantly inhibited the toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB) signaling pathway, which was further confirmed by secreted embryonic alkaline phosphatase (SEAP) assay. Moreover, the molecular docking analysis indicated that oroxylin A might competitively inhibit LPS binding to myeloid differentiation 2 (MD-2) to block the activation of TLR4. The study provided a feasible research strategy for the screening and discovery of antisepsis candidate drugs from TCM.

Anti-Inflammatory Potential of Fucoidan for Atherosclerosis: In Silico and In Vitro Studies in THP-1 Cells

Several diseases, including atherosclerosis, are characterized by inflammation, which is initiated by leukocyte migration to the inflamed lesion. Hence, genes implicated in the early stages of inflammation are potential therapeutic targets to effectively reduce atherogenesis. Algal-derived polysaccharides are one of the most promising sources for pharmaceutical application, although their mechanism of action is still poorly understood. The present study uses a computational method to anticipate the effect of fucoidan and alginate on interactions with adhesion molecules and chemokine, followed by an assessment of the cytotoxicity of the best-predicted bioactive compound for human monocytic THP-1 macrophages by lactate dehydrogenase and crystal violet assay. Moreover, an in vitro pharmacodynamics evaluation was performed. Molecular docking results indicate that fucoidan has a greater affinity for L-and E-selectin, monocyte chemoattractant protein 1 (MCP-1), and intercellular adhesion molecule-1 (ICAM-1) as compared to alginate. Interestingly, there was no fucoidan cytotoxicity on THP-1 macrophages, even at 200 µg/mL for 24 h. The strong interaction between fucoidan and L-selectin in silico explained its ability to inhibit the THP-1 monocytes migration in vitro. MCP-1 and ICAM-1 expression levels in THP-1 macrophages treated with 50 µg/mL fucoidan for 24 h, followed by induction by IFN-γ, were shown to be significantly suppressed as eight- and four-fold changes, respectively, relative to cells treated only with IFN-γ. These results indicate that the electrostatic interaction of fucoidan improves its binding affinity to inflammatory markers in silico and reduces their expression in THP-1 cells in vitro, thus making fucoidan a good candidate to prevent inflammation.

Discovery of quinazoline derivatives CZw-124 as a pan-TRK inhibitor with potent anticancer effects in vitro and in vivo

Herein, we report the discovery process and antitumor activity of the TRK inhibitor CZw-124 (8o), which is a quinazoline derivative. Starting from a PAK4 inhibitor, we used various drug design strategies, including pharmacophore feature supplementation, F-scanning, and blocking metabolic sites, and finally found a TRK inhibitor CZw-124 that is effective in vitro and in vivo. Docking studies and molecular dynamics simulations revealed a possible mode of binding of CZw-124 to TRKA. Biological activity evaluation showed that CZw-124 belongs to a class of pan-TRK inhibitors with moderate kinase selectivity. It inhibited the proliferation and induced the apoptosis of Km-12 cells in vitro by interfering with the phosphorylation of TRKA. Pharmacodynamic evaluation in vivo showed that CZw-124 had a tumor inhibition rate comparable to that of larotrectinib after oral administration of 40 mg/kg/d (tumor growth inhibiton = 71%).

Comment on: Pharmacodynamic evaluation of intermittent versus extended and continuous infusions of piperacillin/tazobactam in a hollow-fibre infection model against Klebsiella pneumoniae.

Comment on: Pharmacodynamic evaluation of intermittent versus extended and continuous infusions of piperacillin/tazobactam in a hollow-fibre infection model against Klebsiella pneumoniae.