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Background: Hereditary angioedema (HAE) due to C1 inhibitor (C1INH) deficiency is characterized by recurrent attacks of edema of the skin and mucosal tissues. Symptoms usually present during childhood (mean age at first attack, 10 years). Earlier symptom onset may predict a more severe disease course. Subcutaneous (SC) C1INH is indicated for routine prophylaxis to prevent HAE attacks in adolescents and adults. We analyzed the long-term efficacy of C1INH (SC) in subjects ≤17 years old treated in an open-label extension (OLE) of the pivotal phase III Clinical Study for Optimal Management of Preventing Angioedema with Low-Volume Subcutaneous C1 Inhibitor Replacement Therapy (COMPACT) trial. Methods: Eligible subjects (age ≥6 years, with ≥4 attacks over 2 consecutive months before entry into the OLE or placebo-controlled COMPACT trial) were treated with C1INH (SC) 40 or 60 IU/kg twice weekly for 52-140 weeks. Subgroup analyses by age (≤17 vs. >17 years) were performed for key efficacy endpoints. Results: Ten subjects were ≤17 years old [mean (range) age, 13.3 (8-16) years, 3 subjects

Objectives Acquired coagulopathy may be associated with bleeding risk. Approaches to restore haemostasis include administration of coagulation factor concentrates, but there are concerns regarding potential prothrombotic risk. The present study assessed the prothrombotic potential of four-factor prothrombin complex concentrate (4F-PCC) versus activated PCC (aPCC) and recombinant factor VIIa (rFVIIa), using three preclinical animal models. Methods The first model was a modified Wessler model of venous stasis-induced thrombosis in rabbit, focusing on dilutional coagulopathy; the second model employed the same system but focused on direct oral anticoagulant reversal (i.e. edoxaban). The third model assessed the prothrombotic impact of 4F-PCC, aPCC and rFVIIa in a rat model of ferric chloride-induced arterial thrombosis. Results In the first model, thrombi were observed at aPCC doses ≥10 IU/kg (therapeutic dose 100 IU/kg) and rFVIIa doses ≥50 μg/kg (therapeutic dose 90 μg/kg), but not 4F-PCC 50 IU/kg (therapeutic dose 50 IU/kg). The impact of 4F-PCC (up to 300 IU/kg) on thrombus formation was evident from 10 minutes post-administration, but not at 24 hours post-administration; this did not change with addition of tranexamic acid and/or fibrinogen concentrate. 4F-PCC-induced thrombus formation was lower after haemodilution versus non-haemodilution. In the second model, no prothrombotic effect was confirmed at 4F-PCC 50 IU/kg. The third model showed lower incidence of thrombus formation for 4F-PCC 50 IU/kg versus aPCC (50 U/kg) and rFVIIa (90 μg/kg). Conclusions These results suggest that 4F-PCC has a low thrombotic potential versus aPCC or rFVIIa, supporting the clinical use of 4F-PCC for the treatment of coagulopathy-mediated bleeding.

Subcutaneous C1-inhibitor (HAEGARDA, CSL Behring), is a US Food and Drug Administration (FDA)-approved, highly concentrated formulation of a plasma-derived C1-esterase inhibitor (C1-INH), which, in the phase III Clinical Studies for Optimal Management in Preventing Angioedema with Low-Volume Subcutaneous C1-inhibitor Replacement Therapy (COMPACT) trial, reduced the incidence of hereditary angioedema (HAE) attacks when given prophylactically. Data from the COMPACT trial were used to develop a repeated time-to-event model to characterize the timing and frequency of HAE attacks as a function of C1-INH activity, and then develop an exposure-response model to assess the relationship between C1-INH functional activity levels (C1-INH(f)) and the risk of an attack. The C1-INH(f) values of 33.1%, 40.3%, and 63.1% were predicted to correspond with 50%, 70%, and 90% reductions in the HAE attack risk, respectively, relative to no therapy. Based on trough C1-INH(f) values for the 40 IU/kg (40.2%) and 60 IU/kg (48.0%) C1-INH (SC) doses, the model predicted that 50% and 67% of the population, respectively, would see at least a 70% decrease in the risk of an attack.

Background For the prevention of attacks of hereditary angioedema (HAE), the efficacy and safety of subcutaneous human C1-esterase inhibitor (C1-INH[SC]; HAEGARDA, CSL Behring) was established in the 16-week Clinical Study for Optimal Management of Preventing Angioedema with Low-Volume Subcutaneous C1-Inhibitor Replacement Therapy (COMPACT). Objective To assess the long-term safety, occurrence of angioedema attacks, and use of rescue medication with C1-INH(SC). Methods Open-label, randomized, parallel-arm extension of COMPACT across 11 countries. Patients with frequent angioedema attacks, either study treatment-naive or who had completed COMPACT, were randomly assigned (1:1) to 40 IU/kg or 60 IU/kg C1-INH(SC) twice per week, with conditional uptitration to optimize prophylaxis (ClinicalTrials.gov registration no. NCT02316353). Results A total of 126 patients with a monthly attack rate of 4.3 in 3 months before entry in COMPACT were enrolled and treated for a mean of 1.5 years; 44 patients (34.9%) had more than 2 years of exposure. Mean steady-state C1-INH functional activity increased to 66.6% with 60 IU/kg. Incidence of adverse events was low and similar in both dose groups (11.3 and 8.5 events per patient-year for 40 IU/kg and 60 IU/kg, respectively). For 40 IU/kg and 60 IU/kg, median annualized attack rates were 1.3 and 1.0, respectively, and median rescue medication use was 0.2 and 0.0 times per year, respectively. Of 23 patients receiving 60 IU/kg for more than 2 years, 19 (83%) were attack-free during months 25 to 30 of treatment. Conclusions In patients with frequent HAE attacks, long-term replacement therapy with C1-INH(SC) is safe and exhibits a substantial and sustained prophylactic effect, with the vast majority of patients becoming free from debilitating disease symptoms.

Human apolipoprotein A-I preparations reconstituted with phospholipids (reconstituted high-density lipoprotein [HDL]) have been used in a large number of animal and human studies to investigate the physiological role of apolipoprotein A-I. Several of these studies observed that intravenous infusion of reconstituted HDL might cause transient elevations in plasma levels of hepatic enzymes. Here we describe the mechanism of this enzyme release. Observations from several animal models and in vitro studies suggest that the extent of hepatic transaminase release (alanine aminotransferase [ALT]) correlates with the movement of hepatic cholesterol into the blood after infusion. Both the amount of ALT release and cholesterol movement were dependent on the amount and type of phospholipid present in the reconstituted HDL. As cholesterol is known to dissolve readily in phospholipid, an HDL preparation was loaded with cholesterol before infusion into rats to assess the role of diffusion of cholesterol out of the liver and into the reconstituted HDL. Cholesterol-loaded HDL failed to withdraw cholesterol from tissues and subsequently failed to cause ALT release. To investigate further the role of cholesterol diffusion, we employed mice deficient in SR-BI, a transporter that facilitates spontaneous movement of cholesterol between cell membranes and HDL. These mice showed substantially lower movement of cholesterol into the blood and markedly lower ALT release. We conclude that initial depletion of hepatic cholesterol initiates transient ALT release in response to infusion of reconstituted HDL. This effect may be controlled by appropriate choice of the type and amount of phospholipid in reconstituted HDL. Copyright © 2015 John Wiley & Sons, Ltd.

Summary Background Recombinant factor VIIa (rFVIIa) is approved for use in controlling bleeding episodes in people with hemophilia who have developed inhibitors to replacement therapy. Due to its short half-life (t½), frequent injections are required, limiting its use as a prophylactic treatment. A novel, recombinant fusion protein linking coagulation factor VIIa with albumin (rVIIa-FP) has been developed to extend the t½ of rFVIIa. Objectives The aim of our studies was to investigate the pharmacokinetic/pharmacodynamic characteristics of rVIIa-FP in preclinical animal species. Methods Pharmacokinetic (PK) parameters were derived after single intravenous dosing in hemophilia A mice, rats, rabbits and monkeys. PK analysis was based on human FVII plasma levels determined by measuring FVII antigen levels by ELISA in mice and rats, and FVIIa activity using STACLOT® VIIa-rTF in rabbits and monkeys. Induction of thrombin generation was investigated in mice, while hemostatic activity was assessed by thrombus formation in rabbits. Results Compared with rFVIIa, rVIIa-FP displayed a prolonged t½, enhanced in vivo recovery and reduced clearance in all species investigated. In mice, 16 h after treatment with rVIIa-FP, thrombin levels were quantifiable, indicating prolonged efficacy, whereas values had approached baseline at this time after treatment with rFVIIa. After 12 h, hemostatic efficacy was negligible in rFVIIa-treated rabbits, but sustained in animals receiving rVIIa-FP. Conclusions These studies indicate that the longer t½ of rVIIa-FP compared with rFVIIa translates into extended activity. These findings suggest that rVIIa-FP has the potential to be administered less frequently than rFVIIa-containing concentrates in clinical use.

Introduction Elderly patients ≥65 years old with hereditary angioedema (HAE) type I/II due to C1-inhibitor (C1-INH) deficiency may have an altered response to treatment and be at higher risk for treatment-related adverse events (AEs) due to comorbidities and polypharmacy. Subcutaneous (SC) C1-INH is indicated for routine prophylaxis to prevent HAE attacks in adolescents and adults. This post-hoc analysis examined the efficacy and safety of C1-INH (SC) in patients ≥65 years old treated in an open-label extension study. Methods Eligible patients (entry criteria: ≥6 years old, ≥4 attacks/8-week interval) were treated with C1-INH (SC) 40 or 60 IU/kg twice weekly and studied for ≤140 weeks. For this analysis, patients were stratified by age ( Results Of 126 patients, 10 were ≥65 years old (mean age [range], 68 years [65-72]; mean duration of treatment, 80 weeks). Elderly patients had a >70% median reduction in attacks relative to their attack rate prior to randomization, with 3 patients being completely attack free for up to 2.4 years. Overall, the most frequently reported AEs were nasopharyngitis, injection-site reactions, headache, and upper respiratory tract infection. No thromboembolic event was reported in these elderly patients. Conclusions C1-INH (SC) is safe and effective for long-term prophylaxis of HAE attacks in elderly patients aged ≥65. These findings are consistent with those from the COMPACT phase III study.

Introduction In women with hereditary angioedema (HAE) due to C1-inhibitor (C1-INH) deficiency, pregnancy can have a variable effect on disease activity. C1-INH concentrate is recommended as first-line therapy for pregnant patients with HAE. Subcutaneous C1-INH (HAEGARDA®, CSL Behring) is indicated for routine prophylaxis to prevent HAE attacks in adolescents and adults. This analysis examines outcomes in patients who became pregnant during C1-INH (SC) treatment in an open-label safety study. Methods Per study protocol, patients who became pregnant during treatment were required to discontinue the study. These patients were assessed during exposure to C1-INH in the open-label study and followed post-discontinuation to assess pregnancy outcomes. Results Four patients discontinued the study due to pregnancy as mandated by the protocol. C1-INH (SC) exposure after the last menstrual period ranged from 4 to 8 weeks (9, 10, 10, and 15 doses). Pregnancy was normal in all cases, with no related complications. All 4 women delivered live healthy infants, 1 by vaginal delivery and 3 by caesarean section at 36 to 40 weeks gestation. No congenital abnormalities were reported. With twice-weekly C1-INH (SC) treatment in the open-label study (total exposure: 25.3-43.1 weeks), 3 women had ≥50% reduction in HAE attacks relative to the number used to qualify for study entry. Three patients had Conclusions In this study, patients with HAE who were exposed to C1-INH (SC) during the first trimester of pregnancy had normal pregnancy outcomes, and all delivered healthy newborns.

Treatment of von Willebrand disease typically requires multiple infusions of von Willebrand factor (VWF)/factor VIII (FVIII) concentrate. Accumulation of FVIII is a clinical concern due to potential risk for thromboembolism. This study sought to determine whether VWF/FVIII concentrate of high VWF:FVIII ratio can prevent FVIII accumulation. VWF-deficient knockout mice received four 150 IU/kg VWF:ristocetin cofactor (RCo) infusions at 3-h intervals, with VWF/FVIII concentrates of a high (Haemate P/Humate-P) or low (Wilate) VWF:FVIII ratio. After each infusion, trough FVIII and VWF levels in plasma were determined. Separately, pharmacokinetic analysis was performed after single 250-IU/kg VWF:RCo infusions of each concentrate. Over the course of the four infusions, trough FVIII increased significantly in the group receiving Wilate (P

Cardiac myocyte apoptosis has been demonstrated in end-stage failing human hearts. The therapeutic utility of blocking apoptosis in congestive heart failure (CHF) has not been elucidated. This study investigated the role of caspase activation in cardiac contractility and sarcomere organization in the development of CHF. In a rabbit model of heart failure obtained by rapid ventricular pacing, we demonstrate, using in vivo transcoronary adenovirus-mediated gene delivery of the potent caspase inhibitor p35, that caspase activation is associated with a reduction in contractile force of failing myocytes by destroying sarcomeric structure. In this animal model gene transfer of p35 prevented the rise in caspase 3 activity and DNA-histone formation. Genetically manipulated hearts expressing p35 had a significant improvement in left ventricular pressure rise (+dp/dt), decreased end-diastolic chamber pressure (LVEDP), and the development of heart failure was delayed. To better understand this benefit, we examined the effects of caspase 3 on cardiomyocyte dysfunction in vitro. Microinjection of activated caspase 3 into the cytoplasm of intact myocytes induced sarcomeric disorganization and reduced contractility of the cells. These results demonstrate a direct impact of caspases on cardiac function and may lead to novel therapeutic strategies via antiapoptotic regimens.

Introduction rVIII-SingleChain (CSL627), a novel recombinant coagulation factor VIII (FVIII), is under investigation in a phase I/III clinical programme (AFFINITY) for the treatment of haemophilia A. Non-clinical studies were conducted to investigate the pharmacokinetic/pharmacodynamic profile of rVIII-SingleChain in comparison with full-length recombinant FVIII. Materials and Methods Binding affinity of rVIII-SingleChain for von Willebrand factor was investigated by surface plasmon resonance analysis. The pharmacokinetic profile of rVIII-SingleChain was compared with a marketed full-length recombinant FVIII concentrate (Advate ® ) in haemophilia A mice, von Willebrand factor knock-out mice, Crl:CD (SD) rats, rabbits and cynomolgus monkeys. Systemic FVIII activity or antigen levels were recorded. Procoagulant activity was measured in an FeCl 3 -induced arterial occlusion model and by recording thrombin generation activity (ex vivo) after administration of 200–250IU/kg rVIII-SingleChain or full-length FVIII to haemophilia A mice. Results rVIII-SingleChain displayed a high affinity for von Willebrand factor (K D =44pM vs. 139 pM for full-length recombinant FVIII). In all animal species tested, rVIII-SingleChain had more favourable pharmacokinetic properties than full-length recombinant FVIII: clearance was decreased and area under the curve and terminal half-life were enhanced vs. full-length recombinant FVIII, while in vivo recovery and volume of distribution were equivalent. rVIII-SingleChain showed a prolonged thrombin generation potential and prolonged procoagulant activity vs. full-length recombinant FVIII in an FeCl 3 -induced arterial occlusion model. Conclusions rVIII-SingleChain had a higher affinity for von Willebrand factor than full-length recombinant FVIII and displayed favourable pharmacokinetic/pharmacodynamic properties in non-clinical models.

Objective— The ability of high-density lipoprotein (HDL) to remove cholesterol from atherosclerotic plaque is thought to underlie its inverse correlation with cardiovascular risk. Our objective was to produce and characterize a human apolipoprotein AI (apoA-I) product optimized to treat clinical atherosclerotic disease. Approach and Results— A new formulation of full length, plasma-derived human apoA-I termed CSL112 was designed to maximize the cholesterol efflux from cells and exhibit favorable pharmacological properties. CSL112 is a disc-shaped particle that strongly elevates cholesterol esterification and shows good pharmacokinetics in rabbits. Infusion of CSL112 into rabbits caused a strong and immediate increase in the ATP binding cassette transporter A1 (ABCA1)-dependent efflux capacity of plasma, an increase in plasma unesterified cholesterol and rapid subsequent cholesterol esterification. In the presence of human plasma, CSL112 was significantly more potent than native HDL at enhancing cholesterol efflux from macrophages, and the efflux elevation was predominantly via the ABCA1 transporter. Consistent with this observation, addition of CSL112 to plasma led to generation of high levels of HDL-VS, a favorable substrate for ABCA1. The lipid profile of plasma did not affect these behaviors. In studies with whole human blood, CSL112 reduced expression of intercellular adhesion molecule 1 and cytokine secretion, and as with cholesterol efflux, these activities were substantially greater than those of native HDL assayed in parallel. Conclusions— CSL112 has favorable pharmacological properties and strongly elevates the ability of plasma to withdraw cholesterol from cells. Preferential elevation of ABCA1-dependent efflux may target atherosclerotic plaque for cholesterol removal and this property makes CSL112 a promising candidate therapy for acute coronary syndrome.

Introduction Fluid resuscitation after trauma often results in dilutional coagulopathy that may hinder control of bleeding and, once initial hemostasis has been secured, heighten risk of perioperative bleeding when further surgery is required. Since multiple coagulation factor deficiencies typically accompany fluid resuscitation, prothrombin complex concentrate (PCC) containing factors II, VII, IX and X may potentially offer greater hemostatic efficacy than coagulation factor monotherapy. Materials and methods Anesthetized normothermic rabbits were hemodiluted 50-60% by phased blood withdrawal and infusion of hydroxyethyl starch and erythrocytes. The animals were randomly assigned to receive saline placebo, 25 IU·kg - 1 PCC (Beriplex P/N) or 180 μg·kg - 1 activated recombinant factor VII (rFVIIa; NovoSeven). Immediately thereafter, bleeding was precipitated by a standardized kidney incision. Results PCC accelerated hemostasis compared both with saline and rFVIIa (p = 0.002 for both comparisons). The median times to hemostasis in the PCC, saline and rFVIIa groups were 12, 19 and 28 min, respectively. PCC reduced blood loss by a median of 43 mL with a 95% confidence interval (CI) of 8.0-67.5 mL vs. saline and 82 mL (CI, 35.0-110.0 mL) vs. rFVIIa. PCC augmented peak thrombin generation by a median of 104.1 n M (CI, 78.3-142.3 n M ) compared with saline and 105.8 n M (CI, 70.7-139.5 n M ) relative to rFVIIa. At the respective 180 μg·kg - 1 and 25 IU·kg - 1 doses tested, rFVIIa displayed thrombogenicity in the Wessler stasis model, while PCC did not. Conclusions In an animal model of dilutional coagulopathy and kidney trauma, PCC accelerated hemostasis and diminished blood loss compared with rFVIIa monotherapy.

Abstract —In heart failure, reduced cardiac contractility is accompanied by blunted cAMP responses to β-adrenergic stimulation. Parathyroid hormone (PTH)–related peptide and arginine vasopressin are released from the myocardium in response to increased wall stress but do not stimulate contractility or adenylyl cyclase at physiological concentrations. To bypass the defective β-adrenergic signaling cascade, recombinant P1 PTH/PTH-related peptide receptors (rPTH1-Rs) and V 2 vasopressin receptors (rV 2 -Rs), which are normally not expressed in the myocardium and which are both strongly coupled to adenylyl cyclase, and recombinant β 2 -adrenergic receptors (rβ 2 -ARs) were overexpressed in cardiomyocytes by viral gene transfer. The capacity of endogenous hormones to increase contractility via the heterologous, recombinant receptors was compared. Whereas V 2 -Rs are uniquely coupled to Gs, PTH1-Rs and β 2 -ARs are also coupled to other G proteins. Gene transfer of rPTH1-Rs or rβ 2 -ARs to adult cardiomyocytes resulted in maximally increased basal contractility, which could not be further stimulated by adding receptor agonists. Agonists at rPTH1-Rs induced increased cAMP formation and phospholipase C activity. In contrast, healthy or failing rV 2 -R–expressing cardiomyocytes showed unaltered basal contractility. Their contractility and cAMP formation increased only at agonist exposure, which did not activate phospholipase C. In summary, we found that gene transfer of PTH1-Rs to cardiomyocytes results in constitutive activity of the transgene, as does that of β 2 -ARs. In the absence of receptor agonists, rPTH1-Rs and rβ 2 -ARs increase basal contractility, coupling to 2 G proteins simultaneously. In contrast, rV 2 -Rs are uniquely coupled to Gs and are not constitutively active, retaining their property to be activated exclusively on agonist stimulation. Therefore, gene transfer of V 2 -Rs might be more suited to test the effects of cAMP-stimulating receptors in heart failure than that of PTH1-Rs or β 2 -ARs.

Abstract 1115 Recombinant factor VIIa (rFVIIa) is approved to control bleeding in hemophilia A and B patients who have developed inhibitory antibodies to replacement therapy and in acquired hemophilia. rFVIIa is rapidly eliminated with a terminal half-life of approximately 2.5 hours in humans. This short half life necessitates frequent injections and considerably limits prophylactic use. A recombinant fusion protein linking activated factor VII with albumin (rVIIa-FP) was engineered to extend the half life of rFVIIa. The present studies were conducted to gather knowledge about the pharmacokinetic and pharmacodynamic (PK/PD) properties of rVIIa-FP in preclinical animals models to enable a more precise estimate of the procoagulant activity of rVIIa-FP for the future clinical use in haemophilia patients with inhibitors to FVIII and FIX. Single intravenous doses of either rVIIa-FP or the licensed rFVIIa comparator, NovoSeven® were administered to mice, rabbits and monkeys. Subsequently, plasma samples were harvested at different time-points after study drug administration and systemic levels of rVIIa-FP or NovoSeven® were assessed either by FVIIa activity measurements using the Staclot® assay system or by FVII antigen measurements using an enzyme linked immunoabsorbance assay (ELISA). When investigating dose responses or duration of hemostatic activity, rVIIa-FP and NovoSeven® were administered to mice or rabbits before tail clip or induction of venous stasis, respectively. Following a single intravenous bolus application the procoagulant activity of both study drugs was assessed in both models at different time points after administration up to 24 hours to proof prolonged procoagulant effects of rVIIa-FP compared to NovoSeven®. Intriguingly, in all animal species tested the systemic bioavailability, clearance and in addition the terminal half-life (t1/2β), of rVIIa-FP were significantly better in comparison to NovoSeven®. Based on FVIIa activity measurements in plasma samples derived from monkeys the 11 fold higher area under the curve (AUC) was accompanied with a 4-fold longer t1/2β, while in vivo recovery (IVR) of rVIIa-FP exceeded that of NovoSeven® by a 70 %. In rabbits the 20 fold higher AUC was associated with a 5-fold longer t1/2β and a 4-fold higher IVR when measuring specific FVIIa activity. In mice measurements of FVII antigen revealed a 11 fold higher AUC, while t1/2β was 4 times longer and IVR was found to be doubled in comparison to NovoSeven®. The assessment of pharmacodynamic activity after dosing based on specific FVIIa activity adjusted by the Staclot® assay revealed, that the procoagulant effect of rVIIa-FP was not different from NovoSeven®, when measuring total blood loss under acute bleeding conditions after tail clip. However, when assessing late time-points after treatment the prolonged systemic availability of rVIIa-FP translated into a longer and sustained hemostatic activity of rVIIa-FP compared to NovoSeven® in both animal models. Intriguingly, ex vivo studies in hemophilia A mice showed that the 4 fold prolonged systemic availability of rVIIa-FP in plasma translates into sustained FVIIa activity when recorded as thrombin generation activity compared to NovoSeven® at 16 hours after treatment. Furthermore in rabbits, the 5 fold longer half-life translated into a significantly greater procoagulant activity as measured by thrombus formation in both jugular veins after venous stasis. In conclusion, the recombinant albumin fusion technology was successfully applied to human recombinant FVIIa for a significantly improved of PK/PD profile as observed in different pre-clinical animal species. Future clinical studies can proof whether the observed improved PK/PD characteristics will also translate into a half-life extension and a longer hemostatic effect in hemophilia patients with inhibitors to FVIII and FIX. Allowed: The entire body of the abstract, including text and tables, must not exceed 3,800 characters. Spaces are not included in this number; title, authors' names, and affiliations are counted separately. Figures are not included in the character count. Disclosures: Zollner: CSL Behring GmbH: Employment. Schuermann:CSL Behring GmbH: Employment. Raquet:CSL Behring GmbH: Employment. Mueller-Cohrs:CSL Behring GmbH: Employment. Weimer:CSL Behring GmbH: Employment. Pragst:CSL Behring GmbH: Employment. Dickneite:CSL Behring GmbH: Employment. Schulte:CSL Behring GmbH: Employment.

Introduction A novel fusion protein linking coagulation factor VIIa with albumin (rVIIa-FP) is currently undergoing clinical investigations. Objective This study was conducted to examine the biodistribution of rVIIa-FP in comparison to recombinant factor VIIa (rFVIIa). Materials and Methods [ 3 H]-rVIIa-FP (10 mg kg − 1 ) or [ 3 H]-rFVIIa (1.6 mg kg − 1 ) were administered intravenously to rats, followed by quantitative whole-body and knee joint autoradiography for 24 ([ 3 H]-rFVIIa) or 240 ([ 3 H]-rVIIa-FP) hours post-dose. Pharmacokinetic and excretion balance analyses were performed. Results In contrast to [ 3 H]-albumin, the tissue distributions of [ 3 H]-rVIIa-FP and [ 3 H]-rFVIIa were similar. Within the knee, both were rapidly present within synovial and mineralized regions. Importantly, rVIIa-FP- and albumin-derived radioactivity were detectable up to 72–120 hours, whereas [ 3 H]-rFVIIa signals were already close to detection limits at 24 hours. The longest rVIIa-FP retention times were observed in bone marrow and endosteum, in which the retention times were up to 5 times longer for rVIIa-FP compared with rFVIIa. Up to 8 hours post-dose, 100% of radioactivity was assigned to unchanged [ 3 H]-rVIIa-FP. Elimination of both proteins occurred primarily via the urine. Conclusions The data suggest that the FVIIa moiety is directing rVIIa-FP’s tissue distribution while the albumin moiety is responsible for the prolonged tissue retention. Importantly, rVIIa-FP is highly concentrated and retained over a long period in the growth plate of the knee joint − a vulnerable site in haemophilia patients. Overall, these improved tissue distribution characteristics of rVIIa-FP may enhance compliance and allow a more convenient dosing frequency.

The efflux of cellular cholesterol mediated by apoA-I and ATP-binding cassette transporter A1 (ABCA1) is thought to underlie many of the cardiovascular benefits of HDL. Several groups have manufactured apoA-I preparations with the aim of making an infused HDL therapy for the acute treatment of