Pharmacokinetic properties of two different recombinant activated factor VII formulations.

Recombinant factor VIIa is indicated for treatment of bleeding episodes in patients with haemophilia A or B with inhibitors; in FVII deficiency and in Glanzmann's thrombasthenia. The aim of the study reported here was to compare the pharmacokinetic profiles between two formulations of rFVIIa that are produced in two different cell lines and media: Chinese hamster ovary cells cultured in a serum-free medium (CHO-rFVIIa) and baby hamster kidney cells cultured in a non-human serum-based medium (BHK-rFVIIa). Two clinical trials were performed; one in healthy subjects and the other in patients with congenital haemophilia A or B, with or without inhibitors. Subjects were recruited into a two-way crossover trial and were randomized to receive a dose of CHO-rFVIIa and BHK-rFVIIa. Healthy subjects received one dose of 90 µg CHO-rFVIIa kg(-1) bodyweight (bw) in the newly developed room-temperature stable rFVIIa formulation and one dose of 90 µg BHK-rFVIIa kg(-1) bw, in the original rFVIIa formulation. Patients with haemophilia received one dose of 270 µg CHO-rFVIIa kg(-1) and one dose of 270 µg BHK-rFVIIa kg(-1), both in the room-temperature stable formulation. The trials showed higher FVII activity levels [higher area under the plasma concentration-time curve (AUC)] following administration of CHO-rFVIIa than after BHK-rFVIIa. Therefore, bioequivalence could not be established. The difference in FVII activity levels is believed to be a result of different glycosylation patterns between the two products. Neither the use of CHO-rFVIIa nor the use of one single dose of 270 µg kg(-1) of the newly developed room-temperature stable rFVIIa raised any safety concerns.

Evaluation of rFVIIa (NovoSeven) in Glanzmann patients with thromboelastogram.

Glanzmann thrombasthenia (GT) is a rare platelet function disorder characterized by a defect in fibrinogen binding to platelet membrane glycoprotein (GP) IIb/IIIa. Recombinant FVIIa (rFVIIa) is a haemostatic agent approved for the treatment of haemophilia patients with inhibitors, patients with acquired haemophilia and in EU also for treatment of factor VII (FVII)-deficient patients and GT patients with antibodies to GPIIb-IIIa. The present study was conducted to evaluate the use of the whole blood test system, rotational thrombelastometry (ROTEM), in measuring the overall haemostasis potential of rFVIIa in 28 GT patients treated with rFVIIa. The correlation of administered rFVIIa and time to start fibrin formation and clot dynamic/stability was assessed and correlation to the clinical response was elucidated. Assessments were performed on predose blood samples spiked with four different concentrations of rFVIIa and whole blood samples taken at 10 and 120 min following dosing. ROTEM parameters clotting time (CT), clot formation time (CFT) and maximum clot firmness (MCF) were measured. Both ex vivo and in vivo data showed beneficial effects on CT in the presence of rFVIIa, but no effect of added rFVIIa was seen on CFT and MCF. In conclusion, the use of thrombelastography at least in the modified form of ROTEM seems to be of limited use in predicting an adequate dose of rFVIIa in GT patients. A good clinical haemostatic response was recorded in spite of the limited changes in the ROTEM pattern supporting the conclusion that ROTEM should not be the method of choice for monitoring rFVIIa therapy in Glanzmann patients.

Evaluation of the safety and pharmacokinetics of a fast-acting recombinant FVIIa analogue, NN1731, in healthy male subjects.

BACKGROUND: NN1731 is a recombinant activated factor VII (rFVIIa) analog with enhanced activity. OBJECTIVES: This clinical trial aimed to assess the safety and pharmacokinetics of single doses of NN1731 in healthy male subjects. METHODS: This was a randomized, placebo-controlled dose-escalation trial with four dose tiers (NN1731 5-30 microg kg(-1)). Eight subjects were randomized to either NN1731 (n = 6) or placebo (n = 2) in each tier. RESULTS: No thromboembolic or serious adverse events were reported and no antibody formation towards NN1731 was detected. NN1731 was demonstrated to be pharmacologically active based on coagulation-related parameters (prothrombin fragment 1+2, activated partial thromboplastin time and prothrombin time). There were five mild/moderate adverse events in three subjects. The FVIIa activity of NN1731 after ascending single-dose administration of NN1731 fits well with a two-compartment model, indicating a bi-exponential decline with a rapid initial distribution of approximately 73% FVIIa activity (half-life = 20 min), followed by a less rapid terminal elimination phase eliminating the remaining 27% (half-life = 3 h). Dose proportionality in healthy male subjects at the dose levels investigated (5-30 microg kg(-1)) was supported by the FVIIa activity data. CONCLUSIONS: Based on the results of this trial, NN1731 appears safe and well tolerated in healthy subjects at doses up to 30 microg kg(-1). No immunogenic or thromboembolic events were reported. The pharmacokinetic profile of NN1731 as measured by FVIIa activity appears to follow two-compartment pharmacokinetics characterized by an initial rapid distribution phase followed by a less rapid elimination phase.

A randomized, double-blind trial demonstrating bioequivalence of the current recombinant activated factor VII formulation and a new robust 25 degrees C stable formulation.

Recombinant activated factor VIIa (rFVIIa) is a well-established treatment for bleeding episodes in patients with congenital or acquired haemophilia A or B with inhibitors to factors VIII and IX and patients with FVII deficiency. The aim of this trial was to demonstrate bioequivalence between the currently marketed (rFVIIa/NovoSeven) and a new rFVIIa formulation (VII25) stable at up to 25 degrees C. Furthermore, short-term safety and tolerability of VII25 and pharmacokinetics of both formulations were investigated. In this single-centre, randomized, double-blind, two-way cross-over trial, healthy male subjects received one intravenous bolus injection of rFVIIa and one of VII25, both at 90 microg kg(-1), in a randomized order 2-3 weeks apart. Mean VII25/rFVIIa ratio for area under the plasma activity-time curve from time 0 to last quantifiable activity (primary bioequivalence endpoint), was 0.93, 90% confidence interval (CI) (0.89-0.96), within the predefined bioequivalence range (0.80-1.25). Secondary pharmacokinetic parameters were comparable between formulations. No serious adverse events were observed. Six mild or moderate treatment-emergent adverse events were reported in five subjects. Coagulation-related parameter profiles were similar between rFVIIa and VII25. No clinically abnormal changes were observed for laboratory parameters and no subjects developed FVIIa antibodies. This trial demonstrated bioequivalence between the currently available rFVIIa and VII25 stable at up to 25 degrees C. VII25's 'user-friendly' formulation removes the inconvenience of storing/transporting at 2-8 degrees C, and as the drug substance is the same, the activity and safety established for rFVIIa is maintained.

[Antioxidant treatment with N-acetylcysteine and vitamin C in patients with chronic bronchitis]. / Antioxidantien-Therapie mit N-Acetylcystein und Vitamin C bei Patienten mit chronischer Bronchitis.

BACKGROUND AND OBJECTIVE: N-acetylcysteine (NAC) is known to have direct antioxidant properties due to its thiol-group on the one hand as well as indirect antioxidant capacity as cysteine-donor to cellular glutathione-synthesis on the other hand. Therefore NAC appears to be attractive in antioxidant therapy of inflammatory disorders of the lung. This study aimed to investigate the use of antioxidant therapy with NAC in chronic bronchitis. PATIENTS AND METHODS: In this randomized, double-blinded and placebo-controlled trial 100 patients divided into four groups were observed over a period of 3 months. The treatment consisted of either 600 mg NAC bid, 500 mg Vitamin C bid, a combination of those two substances using the same dosage or a placebo-preparation. The release of reactive oxygen species from isolated neutrophilic granulocytes and mononuclear cells was quantified before treatment and after three months using chemiluminescence (primary outcome parameter). Furthermore cellular glutathione content of these inflammatory cells was quantified spectrometrically. In addition, leukocyte-count and erythrocyte sedimentation rate as well as spirometry and a standardized symptom-based questionnaire were used to monitor the clinical efficacy. RESULTS: None of the above substances were able to significantly reduce the release of reactive oxygen species from the examined population of inflammatory cells. They also failed to increase intracellular glutathione-levels. Concordantly, no changes in spirometry and the results of the symptom-based questionnaire were found. CONCLUSION: In summary NAC, Vitamin C and the NAC/ Vitamin C-combination did neither enhance antioxidant protection in the blood nor is it of any clinical benefit in chronic bronchitis. Possible reasons may be a lack of antioxidant deficiency in these patients and negative feedback mechanisms of the glutathione-system.

Effects, side effects and plasma concentrations of terbutaline in adult asthmatics after inhaling from a dry powder inhaler device at different inhalation flows and volumes.

1. The efficacy of a metered dose inhaler (MDI) is highly dependent on the mode of inhalation. The relatively high built-in resistance in the Turbohaler (TBH), a new dry powder inhaler device for inhalation of terbutaline sulphate and budesonide, reduces the flow during inhalation. We compared five different modes of inhalation using the terbutaline TBH in 10 stable asthmatic subjects, who were tested on 5 consecutive days. 2. Measurement of 10 different parameters of pulmonary function indicated that the full bronchodilatory effect of an inhaled dose was already achieved at 5 min after the inhalation. Inspiratory flows through the TBH varying from 34 to 88 l min-1 resulted in comparable bronchodilation, and a previous exhalation to residual volume proved of no value. However, if, prior to inhalation, an exhalation through the device was performed, a substantially reduced effect was seen. 3. Reducing the inspiratory flow to approximately 34 l min-1 produced slightly reduced side effects and lower plasma terbutaline concentrations.

Bronchial allergen challenge: dose versus concentration.

This study was designed to investigate if two equivalent doses of allergen administered by different dosing regimes--two breaths and 10 breaths of each concentration--would result in the same magnitude of the early and late asthmatic response. Fifteen patients with extrinsic allergic asthma were challenged twice with either two or 10 breaths of twofold increasing allergen concentrations. The challenge was continued until a 20% decrease in FEV1 had been achieved. A non-cumulative PC20FEV1 allergen was derived, and the cumulative dose of allergen given was similarly derived. In order to assess the reproducibility of the challenge, seven patients were challenged twice with two-breath regime. The mean value of allergen PC20 obtained by the two-breath regime was 4.1 fold (95% CI: 2.3-7.1 fold) greater than those obtained by the 10-breath regime (P less than 0.05), whereas the difference was 1.4 fold (95% CI: -3.3-0.5 fold) for the cumulative dose (P greater than 0.05). A statistically significant larger magnitude of the early asthmatic response, as determined by the maximum per cent fall in FEV1, and late asthmatic response determined by the maximum per cent fall in peak expiratory flow domiciliary recorded during the following 24 hr after challenge, was observed in favour of the 10-breath regime compared to the two-breath regime (mean difference 6%, 95% CI: 0.6-11%). The reproducibility of the provocation test was acceptable (+/- 1.8 two-fold concentration difference). These results confirm the 'equivalent dose hypothesis', and demonstrates that dosage rather than concentration appears to determine the early and late asthmatic response after bronchial allergen challenge.

Beta-2-agonists have antioxidant function in vitro. 1. Inhibition of superoxide anion, hydrogen peroxide, hypochlorous acid and hydroxyl radical.

beta(2)-Agonists are known to have anti-inflammatory efficacy. In this context, beta(2)-agonists are also capable of inhibiting oxidant production of cultured inflammatory cells. As the mechanisms of this function still remain speculative, the purpose of this study was to quantify the efficacy of beta(2)-agonists in vitro to inhibit superoxide anion (O2-), hydrogen peroxide (H2O2), hydroxyl radical (OH.) and hypochlorous acid (HOCl). We tested the following antiasthma drugs: ipratropium bromide, salbutamol (salbutamol base), fenoterol (fenoterol hydrobromide), terbutaline (terbutaline sulfate), isoproterenol, prednisolone (prednisolone hydrogensuccinate), beclomethasone (beclomethasone dipropionate) and theophylline (theophylline sulfate). Antioxidant function was quantified by using the following assay systems: O2- (ferricytochrome c + xanthine/xanthine oxidase), H2O2 (phenol red + 5.10(-6) M H2O2), OH. (deoxyribose assay) and HOCI (HOCl/OCl- in luminol-dependent chemiluminescence). At 10(-4) M, the anti-H2O2 and anti-O2- capacity was as follows: salbutamol/terbutaline < fenoterol < isoproterenol. All beta(2)-agonists (10(-4) M) tested reduced HOCl activity by > 50% (p < 0.01). In contrast, moderate OH. reduction (10-30%) by the beta(2)-agonists is regarded as an nonspecific effect, due to the high concentrations needed (10(-3) M). Corticosteroids and theophylline had no antioxidant effect. These results demonstrate the different redox potentials of different phenol types within the molecular structure of the beta(2)-agonists. The good antioxidative function of isoproterenol is related to ortho formation of the phenol ring, whereas fenoterol has tow phenol rings which can be oxidized. A direct oxidant scavenger function may explain the ability of beta(2)-agonists to reduce the oxidant production of inflammatory cells in vitro.

Oxidant scavenger function of ambroxol in vitro: a comparison with N-acetylcysteine.

Highly reactive oxygen metabolites play an important role in inflammatory processes in the lung. Ambroxol (2-amino-3,5-dibromo-N-[trans-4- hydroxycyclohexyl]benzylamine) has been shown to reduce oxidant-mediated cell damage. However, the mechanism of this effect remains unclear. In order to evaluate oxidant scavenger function increasing concentrations of ambroxol (0-10(-3) mol/l) were compared with equimolar concentrations of N-acetylcysteine (NAC) and glutathione (GSH) in vitro to reduce OH. (hydroxyl radical), HOC1 (hypochlorous acid), O-2 (superoxide anion) and H2O2 (hydrogen peroxide). OH. was measured spectrophotometrically (deoxyribose assay); O-2 (xanthine/x-oxidase), H2O2 and HOC1 (HOC1/OC1-) were determined by chemiluminescence. Ambroxol, NAC and reduced GSH scavenged OH. significantly at 10(-3) mol/l, while HOC1 was inhibited at concentrations > or = 10(-4) mol/l completely (P < 0.01). NAC and GSH had no anti-O-2 function, while ambroxol (10(-4) mol/l) reduced O-2 by 14.3 +/- 6.7%. In contrast, GSH and NAC scavenged H2O2 at > 10(-6) mol/l (P < 0.01), while ambroxol had no anti-H2O2 effect. Our data demonstrate direct oxidant-reducing capabilities of ambroxol, which may be directly related to the aromatic moiety of the molecule. However, high concentrations (micromolar concentrations) are needed. Due to differences in direct oxidant scavenger function, a combination of ambroxol and NAC could be beneficial in antioxidant therapy.

Clinical comparison of inhaled budesonide delivered either via pressurized metered dose inhaler or Turbuhaler.

The aim of this open, randomized cross-over study was to compare the efficacy and safety of inhaled budesonide administered either via a pressurized metered dose inhaler with a 750 ml spacer attached, or via a new dry powder inhaler, Turbuhaler, in 28 patients with stable bronchial asthma. During the 2-week run-in period, the patients received their ordinary inhaled steroid treatment. This was followed by two 4-week periods of active treatment with inhaled budesonide given via Turbuhaler or pressurized MDI. The patients were divided into two groups according to their previous, inhaled steroid doses. Group A received 400 micrograms of budesonide b.i.d, and Group B 800 micrograms of budesonide b.i.d. Diary cards were used by the patients at home to report asthma symptoms, beta 2-agonist consumption, and PEF twice daily, as well as the number of coughs experienced in a 5-min period after steroid inhalation. Budesonide Turbuhaler produced a significantly better effect on morning peak flow than budesonide MDI. The number of coughs in the 5 min after steroid inhalation was significantly lower with the Turbuhaler than with the MDI. In all other parameters recorded (e.g. FEV1, evening PEF, histamine PC20 and other diary measurements) there were no statistically significant differences between the two devices. Turbuhaler was significantly more appreciated than MDI in all questions of preference. The study showed that budesonide via Turbuhaler was at least as effective and safe as budesonide via a pressurized MDI at daily doses of 800 and 1,600 micrograms.(ABSTRACT TRUNCATED AT 250 WORDS)