Clinical Trial: Large-scale Trial Testing the Intensity of CYTOreductive Therapy in Polycythemia Vera (PV)

Study Status: Terminated
Recruit Status: Terminated
Study Type: Interventional

Official Title: A Large-scale Trial Testing the Intensity of CYTOreductive Therapy to Prevent Cardiovascular Events In Patients With Polycythemia Vera (PV)

Brief Summary:

CYTO-PV is a phase III Prospective, Randomized, Open-label, with Blinded Endpoint evaluation (PROBE), multi-center, clinical trial in patients with diagnosis of Polycythemia vera (PV) treated at the best of recommended therapies (e.g.adequate control of standard cardiovascular risk factors). Irrespective of randomized interventions, all patients will be administered low-dose aspirin (when not contraindicated), i.e.the standard antithrombotic treatment in PV patients.

The purpose of this study to demonstrate that a more intensive cytoreductive therapy, plus low-dose aspirin when not contraindicated, with phlebotomy and/or hydroxyurea (HU), aimed at maintaining hematocrit (HCT) < 45% is more effective than a less intensive cytoreduction (either with phlebotomy or HU plus low-dose aspirin when not contraindicated) maintaining HCT in the range of 45-50% in the reduction of CV deaths plus thrombotic events (stroke, acute coronary syndrome [ACS], transient ischemic attack [TIA], pulmonary embolism [PE], splanchnic thrombosis, deep vein thrombosis [DVT], and any other clinically relevant thrombotic event), in patients with Polycythemia Vera treated at the best of recommended therapies (e.g. adequate control of standard cardiovascular risk factors).


Detailed Summary:

Polycythemia vera (PV) is a chronic myeloproliferative disorder characterized by clonal proliferation of hematopoietic progenitors resulting in expansion of the erythrocyte mass, and its clinical course is affected by cardiovascular events, the main cause of morbidity and mortality. Arterial thrombotic events are predominant, particularly large vessel arterial events including cerebrovascular accidents, myocardial infarction, and peripheral arterial occlusion. Based on the complex relationship between thrombosis, hematocrit, and parameters of tissue perfusion and blood viscosity, the latter has been proved to be an exponential function of the hematocrit. Red cell aggregation increases at high hematocrit (HCT) levels, creating the potential for vascular stasis. As a result, enhanced interplay between platelet, leukocytes and vessel wall increases the risk of thrombosis.

Considering the lack of effective therapeutic strategy targeted at the mutated allele JAK2V617F, there is no known treatment that eradicates the abnormal clone, apart from anecdotal cases of bone marrow transplantation. Cytoreductive treatment by phlebotomy or chemotherapy, however, has dramatically reduced the number of thrombotic complications and substantially improved survival and today there is agreement that the goal of cytoreductive treatment should be to keep the HCT value below 0.45 in all PV patients.

This was suggested on the basis of a small, retrospective study of PV that more than 30 years ago showed a progressive increase in the incidence of vascular occlusive episodes at HCT levels higher than 44% and in patients treated according to the drugs and the therapeutic tenets of the time. However no clinical trial has confirmed such findings. The results of the two largest prospective studies currently available (namely PVSG-1 and ECLAP) suggest no
Sponsor: Consorzio Mario Negri Sud

Current Primary Outcome: Reduction of PEP (Primary End Point)defined as CV deaths plus thrombotic events [ Time Frame: Expected average of 5 years ]

To demonstrate that in patients with PV treatment with aggressive cytoreductive therapy aimed at maintaining HCT < 45% is more effective than cytoreductive therapy aimed at maintaining HCT between 45 and 50% in the reduction CV deaths plus thrombotic events (PEP: stroke, acute coronary syndrome [ACS], transient ischemic attack [TIA], pulmonary embolism [PE], abdominal thrombosis, deep vein thrombosis [DVT], and peripheral arterial thrombosis). The minimum clinically relevant beneficial effect is set at a 30% reduction of risk of the PEP.


Original Primary Outcome: Same as current

Current Secondary Outcome: PEP plus minor thrombosis, hospitalization and malignancy [ Time Frame: Expected average of 5 years ]

The events included in the PEP, arterial and venous thrombosis, major and minor thrombosis as well as hospitalization for any reason, hospitalization for CV reason, malignancy and PV-related malignancy (progression to myelofibrosis, myelodysplastic or leukemic transformation) will be analyzed separately to assess the full benefit/risk profile of experimental treatments.


Original Secondary Outcome: Same as current

Information By: Consorzio Mario Negri Sud

Dates:
Date Received: July 17, 2012
Date Started: May 2008
Date Completion: July 2012
Last Updated: July 19, 2012
Last Verified: May 2012