Field Study and Correlative Studies of Factor IX Variant FIX-R338L in Participants Treated with Fidanacogene Elaparvovec.

Background:  Fidanacogene elaparvovec, an adeno-associated virus-based gene therapy vector expressing the high-activity factor IX (FIX) variant FIX-R338L, is in development for hemophilia B. One-stage clotting (OS) assays and chromogenic substrate (CS) assays are commonly used to measure FIX-R338L variant activity. Data from ongoing trials suggest FIX activity varies between different OS and CS assays.

Validation of patient-reported vaso-occlusive crisis day as an endpoint in sickle cell disease studies.

Individuals with sickle cell disease (SCD) experience vaso-occlusive crises (VOC). Historically, VOC episodes have been assessed through medical utilization, thereby excluding events managed at home. In order to validate a daily patient-reported outcome for patients with SCD to accurately report their VOC status and experience of a pain crisis, a SCD Diary was included in Evaluation of Longitudinal Pain Study in Sickle Cell Disease (ELIPSIS), a longitudinal, six-month, non-interventional study.

Hemostatic efficacy of marstacimab alone or in combination with bypassing agents in hemophilia plasmas and a mouse bleeding model.

Background: Patients with hemophilia have deficiencies in intrinsic coagulation factors and can develop inhibitors that limit the effectiveness of replacement coagulation factors. Marstacimab, a human monoclonal antibody, binds and inhibits the human tissue factor pathway inhibitor. Marstacimab is currently under development as a potential prophylactic treatment to prevent bleeding episodes in patients with hemophilia A and B.

Evaluation of Longitudinal Pain Study in Sickle Cell Disease (ELIPSIS) by patient-reported outcomes, actigraphy, and biomarkers.

Clinical trials in sickle cell disease (SCD) often focus on health care utilization for painful vaso-occlusive crises (VOCs). However, no objective, quantifiable pain biomarkers exist, pain is not specific to VOCs, health care utilization varies between patients, unreported at-home VOCs likely contribute to long-term outcomes, and patient-reported outcomes are seldom considered. This noninterventional, longitudinal, 6-month study aimed to develop tools to identify VOCs in SCD patients with or without health care utilization.

Antibodies against the erythroferrone N-terminal domain prevent hepcidin suppression and ameliorate murine thalassemia.

Erythroferrone (ERFE) is produced by erythroblasts in response to erythropoietin (EPO) and acts in the liver to prevent hepcidin stimulation by BMP6. Hepcidin suppression allows for the mobilization of iron to the bone marrow for the production of red blood cells. Aberrantly high circulating ERFE in conditions of stress erythropoiesis, such as in patients with β-thalassemia, promotes the tissue iron accumulation that substantially contributes to morbidity in these patients.

Marstacimab, a tissue factor pathway inhibitor neutralizing antibody, improves coagulation parameters of ex vivo dosed haemophilic blood and plasmas.

Introduction: Tissue factor pathway inhibitor (TFPI) is an endogenous inhibitor of the extrinsic pathway that negatively regulates thrombin production during coagulation. Under haemophilic conditions, where the intrinsic coagulation pathway is impaired, inhibition of TFPI may improve clotting.

Aim: We investigated the ex vivo effects of a human TFPI neutralizing antibody, marstacimab (previously PF-06741086), in coagulation assays including rotational thromboelastometry (ROTEM), thrombin generation assay (TGA) and the dilute prothrombin time (dPT) assay, performed in haemophilic whole blood and plasmas.

Induction and Impact of Anti-Drug Responses Elicited by a Human Recombinant Coagulation Factor FXa in Preclinical Species.

This paper presents a systemic investigation of ADA development and ADA impact of a human coagulation factor in nonclinical species during drug development and provides insights into potential implications in human if a similar ADA occurs. FXa-induced ADA response was characterized in monkey, mouse, rat, and dog in different studies, and ADA effects on pharmacokinetic and/or pharmacodynamics of FXa were further examined in ADA-negative and ADA-positive animals. After repeated administrations, FXa elicited a dose and exposure day-dependent ADA response which ranged from no response to a transient or persistent response.

PF-04447943, a Phosphodiesterase 9A Inhibitor, in Stable Sickle Cell Disease Patients: A Phase Ib Randomized, Placebo-Controlled Study.

This phase Ib study randomized patients with stable sickle cell disease (SCD) aged 18-65 years to twice-daily PF-04447943 (a phosphodiesterase 9A inhibitor; 5 or 25 mg) or placebo, with/without hydroxyurea coadministration, for up to 29 days. Blood samples were collected at baseline and various posttreatment time points for assessments of PF-04447943 pharmacokinetics (PKs)/pharmacodynamics (PDs). Change from baseline in potential SCD-related biomarkers was evaluated.

Translational Pharmacokinetic/Pharmacodynamic Characterization and Target-Mediated Drug Disposition Modeling of an Anti-Tissue Factor Pathway Inhibitor Antibody, PF-06741086.

Tissue factor pathway inhibitor (TFPI) exhibits multiple isoforms, which are known to present in multiple locations such as plasma, endothelium, and platelets. TFPI is an endogenous negative modulator of the coagulation pathway, and therefore, neutralization of TFPI function can potentially increase coagulation activity. A human monoclonal antibody, PF-06741086, which interacts with all isoforms of TFPI is currently being tested in clinic for treating hemophilia patients with and without inhibitors.

Preclinical Pharmacokinetics, Pharmacodynamics, Tissue Distribution, and Interspecies Scaling of Recombinant Human Coagulation Factor Xa.

FXa is a recombinant human FXa variant which is currently being evaluated in the clinic for treating intracerebral hemorrhage. The aim of our studies is to investigate overall pharmacokinetics, pharmacodynamics, and distribution of FXa in preclinical species, and to understand its potential implication in human. Pharmacokinetics of FXa was examined using active site probes and the results showed that FXa displayed fast clearance, low volume of distribution, and a very short plasma resident time in mice, rats, and monkeys.

A zymogen-like factor Xa variant corrects the coagulation defect in hemophilia.

Effective therapies are needed to control excessive bleeding in a range of clinical conditions. We improve hemostasis in vivo using a conformationally pliant variant of coagulation factor Xa (FXa(I16L)) rendered partially inactive by a defect in the transition from zymogen to active protease. Using mouse models of hemophilia, we show that FXa(I16L) has a longer half-life than wild-type FXa and does not cause excessive activation of coagulation.

Inhibition of the Unfolded Protein Response by metformin in renal proximal tubular epithelial cells.

Metformin (Met), an AMP-activated protein kinase (AMPK) inducer, is primarily transported by organic cation transporters expressed at the surface of renal proximal tubular epithelial cells. However, the implication of Met in renal function remains poorly understood. Interestingly, AICAR, another AMPK inducer, has been shown to inhibit the Unfolded Protein Response (UPR) generated by tunicamycin in cardiomyocytes in an AMPK-kinase dependent fashion suggesting metformin may also block the UPR.

A monoclonal antibody against RAGE alters gene expression and is protective in experimental models of sepsis and pneumococcal pneumonia.

The RAGE (receptor for advanced glycation end products) is believed to play a role in sepsis by perpetuating inflammation. The interaction of RAGE with a variety of host-derived ligands that accumulate during stress and inflammation further induces the expression of RAGE. It was previously shown that a rat anti-RAGE monoclonal antibody protected mice from lethality in a cecal ligation and puncture model.

Pharmacokinetics and lung distribution of a humanized anti-RAGE antibody in wild-type and RAGE-/- mice.

A neutralizing antibody to the receptor for the advanced glycation end products (anti-RAGE Ab) was developed as a potential treatment of acute and chronic inflammatory conditions. Previous pharmacology studies demonstrated efficacy of the anti-RAGE antibody in the mouse model of sepsis. We examined pharmacokinetics and lung distribution of [125I]anti-RAGE Ab in RAGE-/- and wild-type (129S5) mice following single IV administration.

IL-22 induces an acute-phase response.

IL-22 is made by a unique set of innate and adaptive immune cells, including the recently identified noncytolytic NK, lymphoid tissue-inducer, Th17, and Th22 cells. The direct effects of IL-22 are restricted to nonhematopoietic cells, its receptor expressed on the surface of only epithelial cells and some fibroblasts in various organs, including parenchymal tissue of the gut, lung, skin, and liver. Despite this cellular restriction on IL-22 activity, we demonstrate that IL-22 induces effects on systemic biochemical, cellular, and physiological parameters.

Complement C3a, CpG oligos, and DNA/C3a complex stimulate IFN-α production in a receptor for advanced glycation end product-dependent manner.

The receptor for advanced glycation end products (RAGE) is a multiligand transmembrane receptor implicated in a number of diseases including autoimmune diseases. To further understand the pathogenic mechanism of RAGE in these diseases, we searched for additional ligands. We discovered that C3a bound to RAGE with an EC(50) of 1.

TREM-1 expression is increased in the synovium of rheumatoid arthritis patients and induces the expression of pro-inflammatory cytokines.

Objectives: To investigate the expression and function of triggering receptor expressed on myeloid cells-1 (TREM-1) in the synovium of human RA patients as well as the level of soluble TREM-1 in the plasma of RA patients.

Methods: Twenty-four RA synovial samples were analysed by gene expression oligonucleotide microarrays. Expression levels of TREM-1 mRNA in murine CIA paws were determined by quantitative PCR (qPCR).

Affinity maturation of a humanized rat antibody for anti-RAGE therapy: comprehensive mutagenesis reveals a high level of mutational plasticity both inside and outside the complementarity-determining regions.

Antibodies that neutralize RAGE (receptor for advanced glycation end products)-ligand interactions have potential therapeutic applications in both acute and chronic diseases. We generated XT-M4, a rat anti-RAGE monoclonal antibody that has in vivo efficacy in an acute sepsis model. This antibody was subsequently humanized.

Expression of the cysteine protease legumain in vascular lesions and functional implications in atherogenesis.

Objective: The present study was conducted to characterize the expression of the cysteine protease legumain in murine and human atherosclerotic tissues, and to explore the molecular mechanisms by which legumain may contribute to the pathophysiology of atherosclerosis.

Methods And Results: Using microarray analysis, legumain mRNA expression was found to increase with development of atherosclerosis in the aorta of aging Apolipoprotein E deficient mice while expression remained at low level and unchanged in arteries of age-matched C57BL/6 control mice. In situ hybridization and immunohistochemical analysis determined that legumain was predominantly expressed by macrophages in the atherosclerotic aorta, in lesions at the aortic sinus and in injured carotid arteries of Apolipoprotein E deficient mice as well as in inflamed areas in advanced human coronary atherosclerotic plaques.

Inhibition of the RAGE products increases survival in experimental models of severe sepsis and systemic infection.

Introduction: The receptor for advanced glycation end products (RAGE), a multi-ligand member of the immunoglobulin superfamily, contributes to acute and chronic disease processes, including sepsis.

Methods: We studied the possible therapeutic role of RAGE inhibition in the cecal ligation and puncture (CLP) model of polymicrobial sepsis and a model of systemic listeriosis using mice genetically deficient in RAGE expression or mice injected with a rat anti-murine RAGE monoclonal antibody.

Results: The 7-day survival rates after CLP were 80% for RAGE-/- mice (n = 15) (P < 0.

Proteomic identification of endothelial proteins isolated in situ from atherosclerotic aorta via systemic perfusion.

The functional and structural alterations of vascular endothelium contribute to the initiation, progression, and complications of atherosclerotic plaque formation, but limited information is known about the molecular composition and pathways underlying pathological changes during atherosclerosis. We have developed an affinity proteomic strategy for in situ isolation and differential mapping of vascular endothelial proteins in normal and atherosclerotic aorta tissues. The selective labeling was carried out by perfusion of the blood vessels with an active biotin reagent for covalent modification of accessible vascular endothelial proteins.

Molecular profile of peripheral blood mononuclear cells from patients with rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic inflammatory arthritis. Currently, diagnosis of RA may take several weeks, and factors used to predict a poor prognosis are not always reliable. Gene expression in RA may consist of a unique signature.

Comparison of osteogenic potentials of human rat BMP4 and BMP6 gene therapy using [E1-] and [E1-,E2b-] adenoviral vectors.

Osteogenic potentials of some recombinant human bone morphogenetic protein (BMP) first-generation adenoviral vectors (ADhBMPs) are significantly limited in immunocompetent animals. It is unclear what role expression of viral proteins and foreign proteins transduced by adenoviral vectors play in the host immune response and in ectopic bone formation. In this study two sets of experiments were designed and performed.

Different osteogenic potentials of recombinant human BMP-6 adeno-associated virus and adenovirus in two rat strains.

The osteogenic potential of AAV5hBMP6 was compared with that of ADhBMP6 in immunodeficient and immunocompetent rats. AAV5hBMP6 (2.3 x 10(12) particles) and ADhBMP6 (5 x 10(7) PFU) elicited viral antibody production in immunocompetent rats.

Effect of adenovirus-mediated overexpression of bovine ADAMTS-4 and human ADAMTS-5 in primary bovine articular chondrocyte pellet culture system.

Introduction: Articular cartilage matrix synthesis and degradation are dynamic processes that must be balanced for proper maintenance of the tissue. In osteoarthritis (OA), this balance is skewed toward degradation and ultimate loss of matrix. The transcriptional and/or activity levels of hundreds of genes are dysregulated in chondrocytes from osteoarthritic cartilage, and a subset of these genes may represent pivotal factors that could be modulated if their specific role in the disease process could be identified.