Chrono-Pharmacological Study of Once Daily Curative Dose of a Low Molecular Weight Heparin (200IU antiXa/kg of Dalteparin) in Ten Healthy Volunteers

1995 ◽  
Vol 74 (02) ◽  
pp. 660-666 ◽  
Author(s):  
P Mismetti ◽  
J Reynaud ◽  
B Tardy-Poncet ◽  
S Laporte-Simitsidis ◽  
M Scully ◽  
...  

SummaryLow molecular weight heparin (LMWH) is currently prescribed for the treatment of deep vein thrombosis at the dose of 100 IU antiXa/kg twice daily or at a dose of 175 IU antiXa/kg once daily with a similar efficacy. We decided to study the chrono-pharmacology of curative dose of LMWH once daily administrated according to the one previously described with unfractionated heparin (UFH).Ten healthy volunteers participated in an open three-period crossover study according to three 24 h cycles, separated by a wash-out interval lasting 7 days: one control cycle without injection, two cycles with subcutaneous injection of 200 IU antiXa/kg of Dalteparin (Fragmin®) at 8 a.m. or at 8 p.m. Parameters of heparin activity were analysed as maximal values and area under the curve.Activated partial thromboplastin time (APTT), thrombin time (TT), prothrombin time (PT) and tissue factor pathway inhibitor (TFPI) were higher after 8 p.m. injection than after 8 a.m. injection (p <0.05) while no chrono-pharmacological variation of anti factor Xa (AXa) activity was observed. Thus the biological anticoagulant effect of 200 IU antiXa/kg of Dalteparin seems to be higher after an evening injection than after a morning injection.A chrono-therapeutic approach with LMWH, as prescribed once daily, deserves further investigation since our results suggest that a preferential injection time may optimise the clinical efficacy of these LMWH.

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 7209-7209
Author(s):  
G. Scheuch ◽  
S. Haeussermann ◽  
P. Brand ◽  
C. Herpich ◽  
T. Meyer

7209 Background: Treatment with Heparin and low molecular weight (LMW) Heparin is frequently used in oncology settings. Usually, these drugs are delivered by subcutaneous (s.c.) administration. Since 1963, the clinical relevance of inhalation of unfractionated as well as LMW-Heparin has been investigated in various studies with over 500 subjects. In this study, a single inhalation of the LMW-Heparin Certoparin (Mono-Embolex, Novartis) was investigated in 10 healthy subjects. The goal was to assess the pharmacokinetic behavior. Inhalations were performed using a novel inhalation system, which allows an accurate dosing in the lungs by controlling patient’s breathing pattern (AKITA). Lung deposition is about 85% of the emitted dose. Methods: 10 non-smoking healthy subjects participated in this study. Inhalation of 9000 IU of LMW-Heparin was compared to 3000 IU s.c. administration to achieve factor-Xa-activity in the plasma of 0.2 to 0.3 U/ml. Intravenous blood samples were taken 0.25, 0.5, 1, 2, 4, 6, 24, 48 hrs after administration. Factor-Xa-activity in plasma was assessed using the Berichrom assay (Dade Behring, Marburg, Germany). Results: Inhalation of LMW-Heparin was well tolerated and did not result in any side effects or changes in lung function. The maximum anti-Xa-activity in the plasma was 0.3 U/ml for the s.c. administration of Certoparin and 0.32 U/ml after inhalation of 9000 IU. However, pharmacokinetics was considerably different. Inhaled LMW-Heparin resulted in a prolonged anti-Xa-activity. After 6 (24) hours, the anti-Xa-activity after s.c. administration was down at 0.16 U/ml (0.10) and after inhalation at 0.30 (0.18) U/ml. Even after 48 hrs, the anti-Xa-activity after inhalation was significantly higher than the baseline value. Comparing area under the curve (AUC), bioavailability for the inhalation was 9.4 U · h/ml ± 14% compared to 5.7 U · h/ml ± 27% after s.c. administration. Conclusions: These results suggest that with controlled inhalation, this administration route is an attractive alternative to s.c. administration, with the result of longer bioavailability and less variability. A once daily administration is possible. Inhalation therapy with these kind of systems might also be useful with different anticancer agents, which cannot be administered orally. [Table: see text]


1987 ◽  
Author(s):  
R Norm ◽  
J Fareed ◽  
I Silber ◽  
A Belo ◽  
R Fenchel ◽  
...  

Subcutaneous pharmacokinetics/pharmacodynamics of a depolymerized low molecular weight heparin (RD 11885) and an unfractionated porcine mucosal heparin (PM 16885) were studied in primates (Macaca mulatta) at 0.5, 1.0 and 2.5 mg/kg/24 hr for 10 days after repeated administration. Ex vivo actions were determined using partial thromboplastin time (APTT), thrombin time (TT), IieptestR time (HT) , anti-factor Xa and anti-factor Ila assays at various time periods. Platelet counts and bleeding times were also measured. The cumulative bioavailability of RD 11885 calculated ex vivo was found to be 2-3 fold higher than PM 16885. The RD 11885 treated group exhibited a clear dissociation of the anti-factor Xa and anti-factor Ila activities. The biological half-life of RD 11885 was significantly greater than PM 16885 in all assays. No staircasing phenomenon was observed with either agent. A desensitization of the PM 16885 effects was observed. Neither agent produced any effect on the bleeding time or platelet count at any time. The pharmacokinetics/pharmacodynamics of RD 11885 were uniform and allowed the calculation of various pharmacologic parameters, whereas inconsistent results were obtained with PM 16885. These results demonstrate that this low molecular weight heparin exhibits better and more predictable bioavailability, in contrast to unfractionated heparin.


1981 ◽  
Author(s):  
H Vinazzer ◽  
A Stemberger ◽  
S Haas

Low molecular weight polysulfated polysaccharides have a considerably weaker influence on overall coagulation than heparin. The activated PTT is however,similarly prolonged by heparin and by low molecular weight heparin analogues. The substances SSHA (Luitpoldwerk, Munich, FRG) and Polyanion SP 54 (Bene-Chemie, Munich, FRG) were examined in detail and were compared to heparin. In vitro,the thrombin time was considerably prolonged by heparin but was minimally influenced by both test substances. The aPTT however, was similarly prolonged by heparin and by the test substances. A series of experiments on factor Xa resulted in a similarly strong inhibition of this activity by heparin and by the test substances whilst inactivation of thrombin was considerably stronger when heparin was present in the system. Single subcutaneous injections of 50 mg heparin given to 10 volunteers resulted in a distinct prolongation of the r- and k-time of the thrombelastogram,of the thrombin time and of the aPTT. 50 mg of the test substances given to the same group of volunteers also prolonged the aPTT but had no influence on the other parameters. The endogenous and exogenous activation of factor Xa from plasma was similarly inhibited by heparin arid by the test substances. Heparin also increased platelet aggregation by collagen. This effect was considerably weaker after injection of the low molecular weight substances. After single injections,all effects subsided within 8 hours. The minimal antithrombin enhancing potency of the two test substances causes a considerably weaker effect on overall coagulation than heparin whilst the potentiating effect of Xa-inhibition is similar in heparin and in both low molecular weight compounds.


1987 ◽  
Author(s):  
R V Johnston ◽  
M Orr ◽  
A Rumley ◽  
J McLachalan ◽  
C D Forbes

Studies of low molecular weight heparin have shown a molecular sized dependency of the anti-coagulant activity. We studied the effects of a low molecular weight heparin LHN-1 (Novo) with a mean molecular weight of 5-7000 daltons on the coagulation mechanism and platelet function of normal volunteers. The heparin was given for 5 days on a once daily dose of 2500, 5000 or 7500 anti-Xa units to 3 groups of volunteers and in a twice daily regime of 2500 and 5000 anti-Xa units in 2 further groups of volunteers. After subcutaneous injection LHN-1 produced a significant (p<0.01) increase in anti-Xa activity which peaked between 3-4 hours after subcutaneous injection on both once and twice daily regime. On once daily regime there was no significant measure able anti-Xa activity 24 hours after the last injection. There was a small but significant increase in both KCCT and thrombin time (p<0.01) following injection, which was also dose related. Bleeding time did not change and there was no effect on platelet function. There was a significant (p<0.01) increase in fibrinolysis as measured by the fibrin plate method. There were no bleeding problems. These findings would suggest that LHN-1 merits further clinical evaluation to confirm its anti-thrombotic and profibrinolytic potential.


1993 ◽  
Vol 70 (06) ◽  
pp. 0909-0914 ◽  
Author(s):  

SummaryFibrin D-Dimer (D-Di), prothrombin activation fragment (F 1+2) and thrombin-antithrombin III complexes (TAT) were measured using ELISA procedures in the plasma of patients with an acute deep venous thrombosis (DVT), at presentation and on days 2, 6 and 10 after initiation of heparin treatment. Patients were randomly allocated into two treatment groups: 44 patients received adapted doses of continuous intravenous unfractionated heparin (UH) whereas 47 received 1 mg/kg every twelve hours of a low molecular weight heparin (enoxaparin) subcutaneously. A phlebography and a perfusion lung scan were performed before inclusion and on day 10. Failure of therapy (n = 9) was defined by venogram worsening or confirmed pulmonary embolism. Improvement (n = 44) or stationary state (n = 38) were defined by venogram evolution in the absence of new leg scan defects.At presentation, D-Di, F 1 + 2 and TAT were above cut-off values in 97, 66 and 89% of patients respectively. D-Di levels correlated with the extent of venous thrombosis whereas TAT and F 1 + 2 did not. Mean levels of D-Di decreased sharply during the first days of treatment but were still abnormal on day 10. A secondary increase of D-Di on days 6 or 10 by more than 3 μg/ml occurred in 4 of the 9 patients who developed a thromboembolic recurrence but in none of the 72 patients who had a more favorable outcome. F 1 + 2 and TAT time-courses were not related to clinical evolution. In the Enoxaparin group, there was no relationship between antifactor Xa activities and any biological markers. TAT and F 1 + 2 levels fell on day 2 and remained stable until day 10. In contrast, in the UH group, TAT and F 1 + 2 did not significantly decrease on day 2, probably due to a delay in dose adaptation, but they declined slowly until day 10.In conclusion, D-Di displays a higher sensitivity than F 1 + 2 or TAT for the diagnosis of D\T. D-Di, but not TAT or F 1 + 2, follow-up seems to be of potential value for early detection of recurrency. Hemostatic activation is controlled earlier by fixed doses of a low molecular weight heparin, irrespective of the plasma anti-factor Xa activities, than by unfractionated heparin at adapted doses.


1993 ◽  
Vol 70 (04) ◽  
pp. 625-630 ◽  
Author(s):  
Edward Young ◽  
Benilde Cosmi ◽  
Jeffrey Weitz ◽  
Jack Hirsh

SummaryThe non-specific binding of anticoagulantly-active heparin to plasma proteins may influence its anticoagulant effect. We used low affinity heparin (LAH) essentially devoid of anti-factor Xa activity to investigate the extent and possible mechanism of this non-specific binding. The addition of excess LAH to platelet-poor plasma containing a fixed amount of unfractionated heparin doubled the anti-factor Xa activity presumably because it displaces anticoagulantly-active heparin from plasma proteins. Although dextran sulfates of varying molecular weights also increased the anti-factor Xa activity, less sulfated heparin-like polysaccharides had no effect. These findings suggest that the ability to displace active heparin from plasma protein binding sites is related to charge and may be independent of molecular size. In contrast to its effect in plasma containing unfractionated heparin, there was little augmentation in anti-factor Xa activity when LAH was added to plasma containing low molecular weight heparin (LMWH), indicating that LMWH binds less to plasma proteins than unfractionated heparin. This concept is supported by studies comparing the anticoagulant activity of unfractionated heparin and LMWH in plasma with that in buffer containing antithrombin III. The anti-factor Xa activity of unfractionated heparin was 2-fold less in plasma than in the purified system. In contrast, LMWH had identical anti-factor Xa activity in both plasma and buffer, respectively. These findings may be clinically relevant because the recovered anti-factor Xa activity of unfractionated heparin was 33% lower in plasma from patients with suspected venous thrombosis than in plasma from healthy volunteers. The reduced heparin recovery in patient plasma reflects increased heparin binding to plasma proteins because the addition of LAH augmented the anti-factor Xa activity. In contrast to unfractionated heparin, there was complete recovery of LMWH added to patient plasma and little increase of anti-factor Xa activity after the addition of LAH. These findings may explain why LMWH gives a more predictable dose response than unfractionated heparin.


1983 ◽  
Vol 49 (02) ◽  
pp. 109-115 ◽  
Author(s):  
M Hoylaerts ◽  
E Holmer ◽  
M de Mol ◽  
D Collen

SummaryTwo high affinity heparin fragments (A/r 4,300 and M, 3,200) were covalently coupled to antithrombin III (J. Biol. Chem. 1982; 257: 3401-3408) with an apparent 1:1 stoichiometry and a 30-35% yield.The purified covalent complexes inhibited factor Xa with second order rate constants very similar to those obtained for antithrombin III saturated with these heparin fragments and to that obtained for the covalent complex between antithrombin III and native high affinity heparin.The disappearance rates from plasma in rabbits of both low molecular weight heparin fragments and their complexes could adequately be represented by two-compartment mammillary models. The plasma half-life (t'/j) of both low Afr-heparin fragments was approximately 2.4 hr. Covalent coupling of the fragments to antithrombin III increased this half-life about 3.5 fold (t1/2 ≃ 7.7 hr), approaching that of free antithrombin III (t1/2 ≃ 11 ± 0.4 hr) and resulting in a 30fold longer life time of factor Xa inhibitory activity in plasma as compared to that of free intact heparin (t1/2 ≃ 0.25 ± 0.04 hr).


Blood ◽  
2004 ◽  
Vol 103 (4) ◽  
pp. 1356-1363 ◽  
Author(s):  
Barbara P. Schick ◽  
David Maslow ◽  
Adrianna Moshinski ◽  
James D. San Antonio

Abstract Patients given unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) for prophylaxis or treatment of thrombosis sometimes suffer serious bleeding. We showed previously that peptides containing 3 or more tandem repeats of heparin-binding consensus sequences have high affinity for LMWH and neutralize LMWH (enoxaparin) in vivo in rats and in vitro in citrate. We have now modified the (ARKKAAKA)n tandem repeat peptides by cyclization or by inclusion of hydrophobic tails or cysteines to promote multimerization. These peptides exhibit high-affinity binding to LMWH (dissociation constant [Kd], ≈ 50 nM), similar potencies in neutralizing anti–Factor Xa activity of UFH and enoxaparin added to normal plasma in vitro, and efficacy equivalent to or greater than protamine. Peptide (ARKKAAKA)3VLVLVLVL was most effective in all plasmas from enoxaparin-treated patients, and was 4- to 20-fold more effective than protamine. Several other peptide structures were effective in some patients' plasmas. All high-affinity peptides reversed inhibition of thrombin-induced clot formation by UFH. These peptides (1 mg/300 g rat) neutralized 1 U/mL anti–Factor Xa activity of enoxaparin in rats within 1 to 2 minutes. Direct blood pressure and heart rate measurements showed little or no hemodynamic effect. These heparin-binding peptides, singly or in combination, are potential candidates for clinical reversal of UFH and LMWH in humans.


1998 ◽  
Vol 79 (05) ◽  
pp. 897-901 ◽  
Author(s):  
Bernard A. Charbonnier ◽  
Jean-Noël Fiessinger ◽  
J. D. Banga ◽  
Ernst Wenzel ◽  
Pascal d’Azemar ◽  
...  

SummaryBackground: Clinical trials have been performed to compare with standard heparin a once or a twice daily regimen of low-molecular-weight heparin but no direct comparison has been done between these two low-molecular-weight heparin regimens in terms of efficacy and safety with a long-term clinical evaluation.Methods: Patients with proximal deep vein thrombosis, confirmed by venography were randomly assigned to either nadroparin (10,250 AXa IU/ml) twice daily or nadroparin (20,500 AXa IU/ml) once daily for at least 5 days. Regimens were adjusted to bodyweight. Oral anticoagulants were started on day 1 or 2 and continued for 3 months. Patients were followed up for 3 months. The composite outcome of venous thromboembolism and death possibly related to pulmonary embolism was the primary measure of efficacy. Major bleeding was the principal measure of safety. The study was designed to show equivalence between the two regimens.Results: Recurrent thromboembolic events or death possibly related to pulmonary embolism were reported in 13 patients in the once daily group (4.1%) and in 24 patients of the twice daily group (7.2%): (absolute difference 3.1% in favor of the once daily regimen; 95% confidence interval -6.6%, +0.5%). Major bleeding episodes during nadroparin treatment occurred in 4 (1.3%) and 4 patients (1.2%) in the once and twice daily groups, respectively.Conclusions: A nadroparin regimen of one injection per day is at least as effective and safe as the same total daily dose divided over two injections for the treatment of acute deep vein thrombosis.


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