scholarly journals 1953. VE303, a Rationally Designed Bacterial Consortium for Prevention of Recurrent Clostridioides difficile (C. Difficile) infection (rCDI), Stably Restores the Gut Microbiota After Vancomycin (vanco)-Induced Dysbiosis in Adult Healthy Volunteers (HV)

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S60-S60 ◽  
Author(s):  
Dmitri Bobilev ◽  
Shakti Bhattarai ◽  
Rajita Menon ◽  
Brian Klein ◽  
Shilpa Reddy ◽  
...  

Abstract Background Gut microbiota alterations and resulting changes in metabolites involved in colonization resistance and host responses, including bile acids (BA) and short-chain fatty acids (SCFA), are hallmarks of C. difficile infection. Reduction in rCDI was shown with fecal microbiota transplants (FMT), but FMT has limitations for routine use and carries unforeseen risks. VE303 is a first-in-class drug being developed for prevention of rCDI consisting of a rationally defined bacterial consortium manufactured under GMP conditions. VE303 comprises 8 distinct species belonging to Clostridium clusters IV, XIVa, and XVII, the commensal bacteria associated with clinical response in FMT, suppress C. difficile growth in vitro and improve survival in vivo. Methods A first-in-human Phase 1 dose-escalation study assessed safety and tolerability of VE303 in HV after vanco-induced dysbiosis. PK (strain colonization and durability) and PD (restoration of the resident microbiota, SCFA pool, and BA pool) were evaluated by metagenomic sequencing and metabolomics analysis of fecal material. Results HV (N = 23) received oral vanco 125 mg QID for 5 days followed by VE303 capsules at escalating single then multiple doses (total dose range 1.6 × 109 to 1.1 × 1011 CFU). VE303-related AEs, mostly gastrointestinal, all Grade 1 and transient, were observed in 35% of HV. Colonization with VE303 strains was abundant, durable (detected at 24 weeks), and dose-dependent. VE303 rapidly expanded 10- to 100-fold and each strain was detectable within 2 days after dosing. VE303 enhanced subjects’ microbiota and metabolic recovery after vanco treatment. When compared with the vanco-only cohort (N = 5), VE303 led to earlier and more complete recovery of beneficial taxa (eg, Bacteroidetes, Firmicutes), reduction in inflammatory taxa (e.g., Proteobacteria) (Figure 1.), and recovery of the secondary BA and SCFA pools. Conclusion VE303, a rationally designed microbial consortium, was safe, well tolerated, and efficiently restored microbiome composition after antibiotic-induced dysbiosis in a dose-dependent manner. VE303 was associated with early recovery of key PD markers of response, including microbiota composition, bile acid, and SCFA pools. A Phase 2 study of VE303 for prevention of rCDI is underway (NCT03788434). Disclosures All Authors: No reported Disclosures.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 3019-3019
Author(s):  
Jordi Rodon Ahnert ◽  
Cesar Augusto Perez ◽  
Kit Man Wong ◽  
Michael L. Maitland ◽  
Frank Tsai ◽  
...  

3019 Background: Protein arginine methyltransferase 5 (PRMT5) methylates multiple substrates known to be dysregulated in cancer, including components of the spliceosome machinery. PF-06939999 is a selective small-molecule inhibitor of PRMT5. Here we report the safety, PK, PD, and preliminary activity of PF-06939999 in patients (pts) with selected advanced/metastatic solid tumors. Methods: This phase 1 dose escalation trial (NCT03854227) enrolled pts with solid tumor types marked by potential frequent splicing factor mutations, including advanced/metastatic endometrial cancer, head and neck squamous cell carcinoma (HNSCC), non-small cell lung cancer (NSCLC), urothelial cancer, cervical cancer, or esophageal cancer. PF-06939999 monotherapy was continuously administered orally QD or BID in 28-day cycles. A Bayesian Logistic Regression Model was used to inform dose level decisions. Primary objectives were to assess dose limiting toxicities (DLTs), AEs and laboratory abnormalities. Tumor response was assessed using RECIST v1.1. PK and PD were assessed by determining PF-06939999 plasma concentration after dosing and changes in plasma levels of symmetric di-methyl arginine (SDMA), the product of PRMT5 enzymatic activity. Results: 28 pts received PF-06939999 at doses from 0.5-12 mg daily (QD or BID) during dose escalation. Median number of cycles was 2 (range, 1-13). Most were female (54%) with a median age of 61.5 (range, 32-84) y. Median number of prior therapies was 4. Overall, 4/24 (17%) pts reported DLTs: thrombocytopenia (n=2, 6 mg BID); anemia (n=1, 8 mg QD); and neutropenia (n=1, 6 mg QD). Treatment-related AEs occurred in 24 (86%) pts. Most common (≥20%) treatment-related AEs across all cycles were anemia (43%), thrombocytopenia (32%), dysgeusia, fatigue and nausea (29% each). Grade ≥3 treatment-related AEs included anemia (25%), thrombocytopenia (21%), fatigue, neutropenia and lymphocyte count decreased (4% each). One pt (6mg BID) had Grade 4 treatment-related thrombocytopenia. All cytopenias were dose-dependent and reversible with dose modification. No pts discontinued treatment for treatment-related toxicity. There were no treatment-related deaths. Exposure to PF-06939999 increased with doses in the dose range tested. Plasma SDMA was reduced at steady state (58.4-87.5%), indicating robust PD target inhibition. Two pts had confirmed partial response (HNSCC and NSCLC). 6 mg QD was identified as the recommended monotherapy dose for expansion. Conclusions: PF-06939999 showed dose-dependent and manageable toxicities in this phase 1 dose escalation study. Objective tumor responses were observed in pts with HNSCC and NSCLC. Analysis of archival tissue for the presence of splicing factor mutations and other potential predictive biomarkers is ongoing. Enrollment to part 2 dose expansion is ongoing in pts with NSCLC, HNSCC and urothelial cancer. Clinical trial information: NCT03854227.


2016 ◽  
Vol 60 (9) ◽  
pp. 5459-5466 ◽  
Author(s):  
Guillermo Villegas ◽  
Giulia Calenda ◽  
Shimin Zhang ◽  
Olga Mizenina ◽  
Kyle Kleinbeck ◽  
...  

ABSTRACTOur recent phase 1 trial demonstrated that PC-1005 gel containing 50 μM MIV-150, 14 mM zinc acetate dihydrate, and carrageenan (CG) applied daily vaginally for 14 days is safe and well tolerated. Importantly, cervicovaginal lavage fluid samples (CVLs) collected 4 or 24 h after the last gel application inhibited HIV-1 and human papillomavirus (HPV) in cell-based assays in a dose-dependent manner (MIV-150 for HIV-1 and CG for HPV). Herein we aimed to determine the anti-HIV and anti-herpes simplex virus 2 (anti-HSV-2) activity of PC-1005 in human cervical explants afterin vitroexposure to the gel and to CVLs from participants in the phase 1 trial. Single HIV-1BaLinfection and HIV-1BaL–HSV-2 coinfection explant models were utilized. Coinfection with HSV-2 enhanced tissue HIV-1BaLinfection.In vitroexposure to PC-1005 protected cervical mucosa against HIV-1BaL(up to a 1:300 dilution) in single-challenge and cochallenge models. CG gel (PC-525) provided some barrier effect against HIV-1BaLat the 1:100 dilution in a single-challenge model but not in the cochallenge model. Both PC-1005 and PC-525 at the 1:100 dilution inhibited HSV-2 infection, pointing to a CG-mediated protection. MIV-150 and CG in CVLs inhibited HIV (single-challenge or cochallenge models) and HSV-2 infections in explants in a dose-dependent manner (P< 0.05). Stronger inhibition of HIV-1 infection by CVLs collected 4 h after the last gel administration was observed compared to infection detected in the presence of baseline CVLs. The anti-HIV and anti-HSV-2 activity of PC-1005 gelin vitroand CVLs in human ectocervical explants supports the further development of PC-1005 gel as a broad-spectrum on-demand microbicide.


2020 ◽  
Vol 38 (15_suppl) ◽  
pp. 7508-7508 ◽  
Author(s):  
Farhad Ravandi ◽  
Roland B. Walter ◽  
Marion Subklewe ◽  
Veit Buecklein ◽  
Mojca Jongen-Lavrencic ◽  
...  

7508 Background: In this open label phase 1 dose escalation study, safety, tolerability, pharmacokinetics, pharmacodynamics and preliminary efficacy of AMG 330 were evaluated in patients (pts) with R/R AML (NCT#02520427). Methods: AMG 330 was evaluated as a continuous IV (cIV) infusion using a 3+3 design. Response was assessed per revised IWG criteria. Each cycle (2–4 weeks duration) was followed by an infusion-free interval. Eligible pts were ≥18 y/o with > 5% blasts in bone marrow and ≥1 line/s of prior therapy. Results: As of December 10, 2019, 55 pts (median age, 58.0 [18.0–80.0] years) were enrolled in 16 cohorts. AMG 330 was administered on 4 schedules (0–3 dose steps) prior to the target dose (TD, 0.5–720 µg/day). Dose steps were implemented in the dose schedule design based on the adverse event (AE) profile. Across all schedules, 55 (100%) pts reported treatment-emergent AEs (any grade). AMG 330–related AEs reported in 49/55 (89%) pts included cytokine release syndrome (CRS; 67%; ≥ grade 3 in 13%), (60%) and nausea (20%) as the most frequent AEs. CRS was reversible and occurred in a dose/schedule-dependent manner mostly within the first 24 hours of administration of triggering AMG 330 dose. The frequency and severity of CRS correlated with the dose level and leukemic burden at baseline. AMG 330 exhibited dose-dependent increase in steady state exposures over the studied dose range with clinical PK profile consistent with cIV administration. Eight of 42 evaluable pts responded: 3 complete remissions (CR; including 1 CR with negative measurable residual disease reported after data snapshot), 4 CR with incomplete hematologic recovery, and 1 morphologic leukemia free state. Seven responders who achieved CR/CRi received a TD equal or above the minimal efficacious dose of 120 μg/day. Among analyzed CR/CRi responders, 4/6 (67%) had adverse cytogenetic risk profile, 3/6 (50%) had ≥4 lines of prior therapy and all had relapsed disease. Responders had higher AMG 330 exposures and 3 responders treated with ≥600 μg/day TD remain in CR/CRi: 1 patient for > 5 months after cycle 1, 1 patient bridged to hematopoietic stem cell transplant after cycle 4 and 1 patient is in cycle 3. Preliminary response assessment showed a correlation with lower tumor burden at baseline with a trend towards higher CD8+ lymphocyte count and E:T ratio. Conclusions: AMG 330 dosed up to 720 μg/day provided early evidence of acceptable safety profile, drug tolerability and anti-leukemic activity, and supports further dose escalation. Clinical trial information: NCT02520427 .


2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 3587-3587 ◽  
Author(s):  
M. N. Pollak ◽  
M. Q. Lacy ◽  
A. Lipton ◽  
L. Demers ◽  
K. Leitzel ◽  
...  

3587 Background: The Insulin like Growth Factor I receptor (IGF-IR), a tyrosine kinase, is widely expressed in human tissues. IGF- IR and its ligands (IGF-I and IGF-II) are expressed by many human cancers (e.g., breast, prostate, colorectal and non-small cell lung). Binding of the ligands to the IGF-IR activates key cellular signaling pathways important for stimulating cellular proliferation and inhibiting apoptosis. IGF- I and IGF-II are present in the circulation, but also locally expressed in neoplastic tissue. Bioavailability of these ligands is regulated by a family of IGF binding proteins (IGFBPs1–6). CP-751,871, a fully human monoclonal antibody, is a highly specific and potent inhibitor of IGF-IR activation. In vitro experiments show that binding of CP 751,871 to IGF-IR induces receptor internalization and degradation. This antibody has been shown to have antineoplastic activity using both in vivo and in vitro pre-clinical models. Methods: Blood samples were collected for characterization of the pharmacokinetic and pharmacodynamic properties of CP-751,871 in phase 1 trials of this agent given to cancer patients either alone or in combination with chemotherapy. The endpoints assessed included among others: CP-751,871 plasma concentrations, total and free IGF-I, IGFBP-3, soluble IGF-IR and IGF-IR expression on granulocytes and tumor cells. Results: CP 751,871 exposure increased with dose over the 800-fold dose range investigated. Pharmacokinetic profiles were consistent with target-mediated disposition. A dose-dependent downregulation of soluble IGF-IR serum concentration and IGF-IR expression was observed, with sustained inhibition for the entire dosing period (3–4 week cycles) observed at doses ≥ 1.5 mg/kg. As predicted for an agent that interferes with IGF-I action, IGF-I and IGFBP-3 serum levels were up-regulated in a similar dose-dependent manner. Conclusions: The pharmacodynamic endpoints of clinical trials provide evidence that CP-751,871 targets IGF-IR in granulocytes, tumor cells and tissues involved in regulation of the growth hormone -IGF-I axis. These data provide proof of principle for the use of CP-751,871 as a first-in-class therapeutic approach to inhibit the IGF-IR pathway in cancer patients. No significant financial relationships to disclose.


2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 8531-8531 ◽  
Author(s):  
K. A. Blum ◽  
M. Smith ◽  
H. Fung ◽  
J. Zalevsky ◽  
D. Combs ◽  
...  

8531 Background: XmAb2513 is a novel 2nd-generation humanized monoclonal antibody (mAb) directed against CD30 (a cell surface antigen expressed on Reed-Sternberg cells of HL and ALCL), with an Fc region engineered to have increased binding affinity to Fcγ receptors (FcγRs) leading to improved FcγR-dependent effector cell functions. In vitro, XmAb2513 was more potent and more efficacious than 1st-generation anti-CD30 mAbs (e.g., SGN-30 & MDX-060). In cynomolgus monkeys (cynos), XmAb2513 exposure was dose-proportional with half-lives ranging from 12 - 17d in repeat dose studies, which suggested biweekly (QOW) dosing in man. A Phase 1 study has been initiated to examine the safety and efficacy of XmAb2513 in patients (pts) with relapsed HL and ALCL. Methods: Phase 1 open-label study with QOW dosing of XmAb2513; dose-escalation study design with doses of 0.3, 1, 3, 6, 9, and 12 mg/kg via IV-infusion to establish the maximum tolerated dose (MTD). Pts receive up to 4 cycles (8 infusions) with sample collections at regular intervals for safety, PK, soluble CD30 (sCD30) and detection of immunogenicity [i.e., human Abs to humanized Abs (HAHA)]. Tumor response is assessed every 2 cycles. Results: 13 HL pts have been enrolled in the 1st 4 dose levels (0.3 to 6 mg/kg). XmAb2513 has been well tolerated. The MTD has not been achieved. 1 pt with an extensive treatment history and chronic immunosuppression died due to fungal pneumonia after a single 3 mg/kg dose. The event was considered unrelated to XmAb2513. PK parameters were computed for the 1st dose alone and for the entire course of XmAb2513 treatment. PK parameters appeared non-linear across the dose range from 0.3 - 3 mg/kg. Half-life appeared to increase after multiple infusions and ranged from 5.3 - 30.2 days in the 1 and 3 mg/kg cohorts. Immunogenicity (HAHA) results have been negative. Tumor reduction has been observed in 1 pt in the 1 mg/kg cohort and 2 in the 3 mg/kg cohort. Conclusions: The MTD of XmAb2513 has not yet been reached due to its tolerability and lack of immunogenicity. PK results are on track with simulations based on PK results from cynos. XmAb2513 has demonstrated encouraging biologic activity in patients with refractory HL. [Table: see text]


1981 ◽  
Vol 241 (2) ◽  
pp. F186-F195
Author(s):  
H. J. Rodriguez ◽  
S. K. Sinha ◽  
J. Starling ◽  
S. Klahr

The effects of single and multiple injections of aldosterone and dexamethasone on renal Na+-K+-ATPase, in vitro renal gluconeogenesis, and urinary electrolyte excretion were examined in adrenalectomized rats in a dose-dependent manner. Single maximal and supramaximal doses of aldosterone (defined by the effect of electrolyte excretion) had no effect on Na+-K+-ATPase or gluconeogenesis. By contrast, a single administration of dexamethasone (in a dose range that increased fasting blood sugar, stimulated renal gluconeogenesis, and had no mineralocorticoid effects) yielded clear-cut activation of Na+-K+-ATPase. Multiple submaximal doses of dexamethasone produced quantitatively similar stimulation of Na+-K+-ATPase and gluconeogenesis. Multiple supramaximal doses of aldosterone stimulated Na+-K+-ATPase and gluconeogenesis, but maximal and submaximal doses of the hormone were without effect. Aldosterone had no effect on hepatic Na+-K+-ATPase or gluconeogenesis. These results suggest that activation of renal Na+-K+-ATPase can be considered a putative glucocorticoid (not mineralocorticoid) effect. Renal Na+-K+-ATPase activation by chronic aldosterone treatment may be mediated by glucocorticoid receptor sites and, hence, may not represent a genuine mineralocorticoid effect.


1984 ◽  
Vol 107 (3) ◽  
pp. 395-400 ◽  
Author(s):  
Itaru Kojima ◽  
Etsuro Ogata ◽  
Hiroshi Inano ◽  
Bun-ichi Tamaoki

Abstract. Incubation of 18-hydroxycorticosterone with the sonicated mitochondrial preparation of bovine adrenal glomerulosa tissue leads to the production of aldosterone, as measured by radioimmunoassay. The in vitro production of aldosterone from 18-hydroxycorticosterone requires both molecular oxygen and NADPH, and is inhibited by carbon monoxide. Cytochrome P-450 inhibitors such as metyrapone, SU 8000. SU 10603, SKF 525A, amphenone B and spironolactone decrease the biosynthesis of aldosterone from 18-hydroxycorticosterone. These results support the conclusion that the final reaction in aldosterone synthesis from 18-hydroxycorticosterone is catalyzed by an oxygenase, but not by 18-hydroxysteroid dehydrogenase. By the same preparation, the production of [3H]aldosterone but not [3H]18-hydroxycorticosterone from [1,2-3H ]corticosterone is decreased in a dose-dependent manner by addition of non-radioactive 18-hydroxycorticosterone.


This trial research was performed to discuss the immune-influence of Melaleuca leucadendra ‘paper-bark tree’ dried leaves which is an important medical plant known in many regions in the world. The leaves were dissolved in a mixture of (ethanol + water) (3:1) mixture, then filtered, evaporated and dried under reduced pressure to obtain leaves extract. The macrophages of blood derived origin were provided from rats and mixed with three different leaves extracts doses in tissue culture plates and incubated then stained with fluorescent acridine orange and examined under fluorescent microscope to assess the phagocytic and killing potency. The wells contents were aspirated and assayed for nitric oxide and interleukin-2 levels. The results displayed an obvious increase in phagocytic, killing performance as well as nitric oxide and IL-2 level production than control in a dose dependent manner. The obtained results suggested the immune-stimulant impact of the paper-bark tree leaves.


2001 ◽  
Vol 91 (6) ◽  
pp. 2703-2712 ◽  
Author(s):  
Stephen M. Johnson ◽  
Julia E. R. Wilkerson ◽  
Daniel R. Henderson ◽  
Michael R. Wenninger ◽  
Gordon S. Mitchell

Brain stem preparations from adult turtles were used to determine how bath-applied serotonin (5-HT) alters respiration-related hypoglossal activity in a mature vertebrate. 5-HT (5–20 μM) reversibly decreased integrated burst amplitude by ∼45% ( P < 0.05); burst frequency decreased in a dose-dependent manner with 20 μM abolishing bursts in 9 of 13 preparations ( P < 0.05). These 5-HT-dependent effects were mimicked by application of a 5-HT1A agonist, but not a 5-HT1B agonist, and were abolished by the broad-spectrum 5-HT antagonist, methiothepin. During 5-HT (20 μM) washout, frequency rebounded to levels above the original baseline for 40 min ( P < 0.05) and remained above baseline for 2 h. A 5-HT3 antagonist (tropesitron) blocked the post-5-HT rebound and persistent frequency increase. A 5-HT3 agonist (phenylbiguanide) increased frequency during and after bath application ( P < 0.05). When phenylbiguanide was applied to the brain stem of brain stem/spinal cord preparations, there was a persistent frequency increase ( P < 0.05), but neither spinal-expiratory nor -inspiratory burst amplitude were altered. The 5-HT3receptor-dependent persistent frequency increase represents a unique model of plasticity in vertebrate rhythm generation.


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