Prolongation of the Interval Between Prothrombin Time Tests in Stable Patients II (PRINT-II)
18 mars 2014 mis à jour par: Sam Schulman, McMaster University
Prolongation of the Interval Between Prothrombin Time Tests in Stable Patients II (the PRINT II Study): a Randomized Controlled, Non-inferiority Trial Comparing 4-weekly With 12-weekly Testing and Dose-assessment
More than 2 million patients in North America are treated with warfarin - a "blood thinner" - to prevent blood clots in arteries or veins.
The treatment has to be monitored with a blood test and the dose changed accordingly every 1-4 weeks.
One third of the patients have very stable results and hardly ever have to change the dose.
The investigators wish to show that the level of control of the treatment with warfarin in these very stable patients is not worse with 12-weekly testing.
A pilot study the investigators performed indicated that 12-weekly testing would be safe but this has to be confirmed in a large study.
One third of patients taking warfarin have not had any changes in the dose for the past 6 months or longer.
These patients will be asked about participation in the study.
They will be randomized to testing and dosing every 4 or 12 weeks.
Each patient is in the study until it ends, which will be minimum 1 year and can be up to about 4 years.
The study is designed to show that 12-weekly testing does not significantly increase the risk for major bleeding or blood clots.
The results would be important for a large number of patients.
An increase of the interval between blood tests from 4 to 12 weeks would reduce the burden for these patients on life-long treatment considerably.
Aperçu de l'étude
Statut
Retiré
Les conditions
Intervention / Traitement
Description détaillée
The study is a randomized, controlled, open-label, multi-center non-inferiority trial to demonstrate that the interval between internation normalized ration (INR) tests can be extended from the recommended 4 weeks to 12 weeks for patients with stable INRs.
PROBE design.
Patients receiving warfarin therapy that have exhibited INR stability, defined as no change in maintenance dose for at least 6 months, are potentially eligible for enrolment in the study.
The primary outcome is a composite of major bleeding (ISTH criteria) plus objectively verified arterial or venous thromboembolism (excluding superficial thrombophlebitis) plus death related to thromboembolism.
Justification: the study is not reflecting a "trade-off" scenario where one regimen is expected to be more effective at the cost of increased harm compared to the other regimen.
Conversely, the potential disadvantage of the experimental regimen in this trial is increased variability in INR, which may result in an increased rate of low as well as high INRs and therefore potentially an increase of both types of clinical events.
Type d'étude
Interventionnel
Phase
- Phase 3
Contacts et emplacements
Cette section fournit les coordonnées de ceux qui mènent l'étude et des informations sur le lieu où cette étude est menée.
Lieux d'étude
-
-
Ontario
-
Hamilton, Ontario, Canada, L8L 2X2
- Hamilton Health Sciences - General Hospital
-
-
Critères de participation
Les chercheurs recherchent des personnes qui correspondent à une certaine description, appelée critères d'éligibilité. Certains exemples de ces critères sont l'état de santé général d'une personne ou des traitements antérieurs.
Critère d'éligibilité
Âges éligibles pour étudier
18 ans et plus (Adulte, Adulte plus âgé)
Accepte les volontaires sains
Non
Sexes éligibles pour l'étude
Tout
La description
Inclusion Criteria:
- long-term warfarin for prophylaxis of arterial embolism due to atrial fibrillation or mechanical heart valve replacement OR secondary prophylaxis after VTE
- therapeutic INR range of 2.0-3.0 or 2.5-3.5
- anticoagulation therapy has been managed by the study site for at least 6 months prior to enrollment
- warfarin maintenance dose has remained unchanged for the previous 6 months or longer
Exclusion Criteria:
- Age < 18 years
- Life expectancy of less than 1 year
- Congestive heart failure or other diagnosis where the condition or its treatment is expected to affect the stability of INR (e.g. cancer requiring chemotherapy)
- Attending physician believes that patient is not suitable for the study (for instance, psychiatric disorder; history of non-compliance; newly diagnosed disease which by itself, via the treatment required or the effects thereof may cause instability of INRs)
- Patients who perform self-testing
- Geographic inaccessibility
- Failure to obtain written consent
Plan d'étude
Cette section fournit des détails sur le plan d'étude, y compris la façon dont l'étude est conçue et ce que l'étude mesure.
Comment l'étude est-elle conçue ?
Détails de conception
- Objectif principal: Traitement
- Répartition: Randomisé
- Modèle interventionnel: Affectation parallèle
- Masquage: Aucun (étiquette ouverte)
Armes et Interventions
Groupe de participants / Bras |
Intervention / Traitement |
|---|---|
|
Aucune intervention: Standard interval between PT testing
Prothrombin time (PT) is tested every 4 weeks, according to American College of Chest Physicians (ACCP) Guidelines up to 2008 for stable patients on warfarin.
|
|
|
Expérimental: Prolonged interval between PT testing
Prothrombin time (PT) is tested every 12 weeks, according to suggestion in American College of Chest Physicians (ACCP) Guidelines of 2012 for stable patients on warfarin.
|
Patients in the intervention group will be scheduled for prothrombin time testing and dosing of warfarin every 12 weeks instead of every 4 weeks.
This has been suggested in the latest edition of the ACCP guidelines as a possibility for very stable patients.
In order to change this from a suggestion to a formal recommendation a study powered for clinically important outcomes is needed.
Autres noms:
|
Que mesure l'étude ?
Principaux critères de jugement
Mesure des résultats |
Description de la mesure |
Délai |
|---|---|---|
|
Composite of major bleeding and objectively verified arterial or venous thromboembolism
Délai: Average 3 years
|
The justification for a composite outcome including both bleeding and thromboembolism is that the study is not reflecting a "trade-off" scenario where one regimen is expected to be more effective at the cost of increased harm compared to the other regimen.
Conversely, the potential disadvantage of the experimental regimen in this trial is increased variability in prothrombin time, which may result in an increased rate of short as well as long prothrombin times and therefore potentially an increase of both types of clinical events.
|
Average 3 years
|
Mesures de résultats secondaires
Mesure des résultats |
Description de la mesure |
Délai |
|---|---|---|
|
All-cause mortality
Délai: Average 3 years
|
Average 3 years
|
|
|
Any bleeding
Délai: Average 3 years
|
This is the composite of major and minor bleeding
|
Average 3 years
|
Collaborateurs et enquêteurs
C'est ici que vous trouverez les personnes et les organisations impliquées dans cette étude.
Parrainer
Publications et liens utiles
La personne responsable de la saisie des informations sur l'étude fournit volontairement ces publications. Il peut s'agir de tout ce qui concerne l'étude.
Publications générales
- Schulman S, Parpia S, Stewart C, Rudd-Scott L, Julian JA, Levine M. Warfarin dose assessment every 4 weeks versus every 12 weeks in patients with stable international normalized ratios: a randomized trial. Ann Intern Med. 2011 Nov 15;155(10):653-9, W201-3. doi: 10.7326/0003-4819-155-10-201111150-00003.
- Pengo V, Barbero F, Biasiolo A, Pegoraro C, Cucchini U, Iliceto S. A comparison between six- and four-week intervals in surveillance of oral anticoagulant treatment. Am J Clin Pathol. 2003 Dec;120(6):944-7. doi: 10.1309/U716-4E0X-H5UE-RKRV.
Dates d'enregistrement des études
Ces dates suivent la progression des dossiers d'étude et des soumissions de résultats sommaires à ClinicalTrials.gov. Les dossiers d'étude et les résultats rapportés sont examinés par la Bibliothèque nationale de médecine (NLM) pour s'assurer qu'ils répondent à des normes de contrôle de qualité spécifiques avant d'être publiés sur le site Web public.
Dates principales de l'étude
Début de l'étude
1 avril 2014
Achèvement primaire (Anticipé)
1 avril 2018
Achèvement de l'étude (Anticipé)
1 octobre 2018
Dates d'inscription aux études
Première soumission
21 juillet 2012
Première soumission répondant aux critères de contrôle qualité
26 juillet 2012
Première publication (Estimation)
31 juillet 2012
Mises à jour des dossiers d'étude
Dernière mise à jour publiée (Estimation)
20 mars 2014
Dernière mise à jour soumise répondant aux critères de contrôle qualité
18 mars 2014
Dernière vérification
1 mars 2014
Plus d'information
Termes liés à cette étude
Termes MeSH pertinents supplémentaires
- Processus pathologiques
- Maladies cardiovasculaires
- Maladies vasculaires
- Maladies des voies respiratoires
- Artériosclérose
- Maladies artérielles occlusives
- Maladies pulmonaires
- Embolie et thrombose
- Athérosclérose
- Arythmies cardiaques
- Maladies cardiaques
- Embolie
- Maladie artérielle périphérique
- Maladies vasculaires périphériques
- Fibrillation auriculaire
- Thrombose
- La thrombose veineuse
- Maladies des valves cardiaques
- Embolie pulmonaire
Autres numéros d'identification d'étude
- PRINT-II-2012
Ces informations ont été extraites directement du site Web clinicaltrials.gov sans aucune modification. Si vous avez des demandes de modification, de suppression ou de mise à jour des détails de votre étude, veuillez contacter register@clinicaltrials.gov. Dès qu'un changement est mis en œuvre sur clinicaltrials.gov, il sera également mis à jour automatiquement sur notre site Web .