Anemia, Atherosclerosis, Cardiovascular, CKD
Conditions
Keywords
erythropoietin
Brief summary
Although several large well designed clinical trials have shown that erythropoietin which is commonly used to treat anemia associated with kidney disease, increases the risk of stroke and heart disease, the mechanism for this increased risk is unknown. The investigators' preliminary studies show that the adverse effects of erythropoietin are from activation of the heterodimeric erythropoietin/ beta common receptor which only occurs with high doses of erythropoietin. The investigators propose a clinical trial of 120 patients assigned to low doses of erythropoietin given more frequently or the same cumulative dose of erythropoietin administered as a high dose once every two weeks and assess effects on the beta common receptor activation, inflammation and vascular disease as evidence by MRI of the carotid arteries.
Detailed description
Erythropoietin (EPO) is the most widely prescribed cytokine, yet the benefits and potential side effects of different dosing regimens are poorly understood. It is now recognized that erythropoietin administered at high doses to patients with chronic kidney disease, results in an increased risk of morbidity and mortality from heart disease and stroke. However, the mechanisms that mediate this increased risk of cardiovascular disease is not known. There are two receptors for erythropoietin the homodimeric EPO receptor (EPOR) and the heterodimeric beta common receptor ( CR)/EPOR. The investigators have demonstrated that activation of the heterodimeric CR/EPOR only occurs with high doses of EPO. Our exciting, published, preliminary data also demonstrates that the CR is in a complex with vascular endothelial growth factor receptor-2 (VEGFR-2) and that high doses of EPO activate VEGFR-2 through the CR, resulting in the deleterious effects of VEGFR-2 activation on the cardiovascular system. This is particularly important in patients with kidney disease since they are already at a high risk of cardiovascular disease. Moreover in advanced kidney disease cyanate derived from the high urea levels can non-enzymatically form an amide bond with EPO. This carbamylated EPO (cEPO) has no effect on hemoglobin, but still activates the heterodimeric CR/EPOR. To date there have been no studies that have directly measured levels of cEPO or activation of the CR/EPOR in patients with kidney disease. Our hypothesis is that the administration of low-doses of EPO more frequently will result in lower levels of total and carbamylated erythropoietin decreased activation of VEGFR-2 via the heterodimeric CR/EPOR and consequently decreased inflammation and atherosclerosis. The investigators will directly test this hypothesis by randomly allocating 120 patients with chronic kidney disease to either low- dose EPO given thrice weekly or the same cumulative dose, a high-dose, administered once every 2 weeks. Our hypothesis predicts that low-dose EPO will be as effective at correcting anemia, but will demonstrate less progression of carotid artery plaque, as assessed by non-contrast magnetic resonance imaging, as compared to the high-dose, EPO given every 2 weeks. To delineate how EPO affects blood vessels, the investigators will isolate endothelial cells from blood vessels in 20 patients who are assigned to low-dose EPO and 20 allocated to high-dose EPO. Within these cells the investigators will investigate the signaling pathways that are triggered by activation of CR/EPOR. In a substudy of 20 subjects with kidney disease randomized to low-dose EPO or to high-dose EPO, as well as 20 healthy controls receiving a single dose of high- or low-dose EPO, the investigators will determine how kidney function and dosing affects levels of total and carbamylated erythropoietin. The investigators' study will not only provide us with a thorough understanding of the mechanism by which EPO mediates the increased risk of atherosclerosis, but a clinical strategy to avoid the side effects of EPO therapy and a tool to quantify the cardiovascular risk of EPO and newer erythropoiesis stimulating agents by assessing activation of the heterodimeric CR/EPOR.
Interventions
DRUGLow dose erythropoietin
Subjects randomized to this arm will receive low-dose of EPO administered thrice weekly
DRUGHigh dose erythropoietin
Subjects randomized to this arm will receive the same cumulative dose of EPO administered as a high-dose of EPO every 2 weeks
Sponsors
VA Office of Research and Development
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Masking description
The outcome is the progression of carotid plaque. John Forder, PhD, who will read the MRIs will be blinded to the subject and treatment group.
Intervention model description
Patients will be randomly assigned two different erythropoietin dosing strategies. One group will be given more frequent, low-doses of EPO and the other group will be given the same, cumulative dose given every 2 weeks.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
The investigators will enroll Veterans who fulfill the following criteria: * stage 3, 4, or 5 CKD (estimated glomerular filtration rate of less than 60 ml/min/1.73 m2) on at least two separate occasions greater than 3 months apart; and * candidates for EPO therapy as per the National Kidney Foundation's Kidney Disease Outcomes Quality Initiative guidelines (hemoglobin \< 10 gm/dL and anemia of CKD).
Exclusion criteria
The investigators will exclude any Veteran who meets any of the following criteria: 1. pregnant, planning to become pregnant in the next year, or breast feeding; 2. uncontrolled hypertension (blood pressure \> 180/100 mm Hg despite optimal antihypertensive medications); 3. active gastrointestinal bleeding (visible blood or positive tests for stool occult blood accompanied by a decrease in hemoglobin); 4. likely to have EPO resistance; 5. an adverse cardiovascular event in the prior three months; 6. active or recent (within the last 3 months) severe, systemic infection; 7. active inflammatory disease such as lupus, rheumatoid arthritis, or vasculitis requiring immunosuppressive or immunomodulatory medications; 8. history of solid organ transplantation; 9. expected off-dialysis survival of less than one year (as determined by the estimated glomerular filtration slope and the treating physician; 10. active cancer (undergoing chemotherapy or radiation within the last 3 months) or primary bone marrow disease such as myelofibrosis; or 11. a contraindication for an MRI or individuals who cannot comply with the study protocol. The investigators will exclude healthy subjects that meet a, b, f, g, h, or j.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Carotid Total Plaque Volume From Baseline to Approximately 1 Year, as Assessed by Non-contrast MRI | 1 year | The plaque characteristics will be analyzed by MRI-PlaqueViewTM (VP diagnostics Inc., WA). Planimetry will be performed on the image data sets, using histogram equalization to improve edge detection for plaque, arterial wall and lumen. Differences in image contrast between T1-weighted, T2-weighted, Time of Flight, and proton density will be used to characterize the plaque as fibrous, stable, or unstable. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Severity of Maximal Stenosis at Baseline and Upon Follow-up. | 1 year | The plaque characteristics will be analyzed by MRI-PlaqueViewTM (VP diagnostics Inc., WA). Planimetry will be performed on the image data sets, using histogram equalization to improve edge detection for plaque, arterial wall and lumen. Differences in image contrast between T1-weighted, T2-weighted, Time of Flight, and proton density will be used to characterize the plaque as fibrous, stable, or unstable. |
| Percentage of Total Plaque Area at Baseline and Upon Follow-up. | 1 year | The plaque characteristics will be analyzed by MRI-PlaqueViewTM (VP diagnostics Inc., WA). Planimetry will be performed on the image data sets, using histogram equalization to improve edge detection for plaque, arterial wall and lumen. Differences in image contrast between T1-weighted, T2-weighted, Time of Flight, and proton density will be used to characterize the plaque as fibrous, stable, or unstable. |
| Characteristics of Plaques (Soft or Fibrous and Stable or Unstable) at Baseline and Upon Follow-up. | 1 year | The plaque characteristics will be analyzed by MRI-PlaqueViewTM (VP diagnostics Inc., WA). Planimetry will be performed on the image data sets, using histogram equalization to improve edge detection for plaque, arterial wall and lumen. Differences in image contrast between T1-weighted, T2-weighted, Time of Flight, and proton density will be used to characterize the plaque as fibrous, stable, or unstable. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Low Dose Erythropoietin Subjects randomized to this arm will receive low-dose of EPO administered thrice weekly
Low dose erythropoietin: Subjects randomized to this arm will receive low-dose of EPO administered thrice weekly | 3 |
| High Dose Erythropoietin Subjects randomized to this arm will receive the same cumulative dose of EPO administered as a high-dose of EPO every 2 weeks
High dose erythropoietin: Subjects randomized to this arm will receive the same cumulative dose of EPO administered as a high-dose of EPO every 2 weeks | 2 |
| Total | 5 |
Baseline characteristics
| Characteristic | Low Dose Erythropoietin | High Dose Erythropoietin | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 1 Participants | 1 Participants | 2 Participants |
| Age, Categorical Between 18 and 65 years | 2 Participants | 1 Participants | 3 Participants |
| Age, Continuous | 65 years STANDARD_DEVIATION 10 | 68 years STANDARD_DEVIATION 5 | 67 years STANDARD_DEVIATION 8 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants | 0 Participants | 0 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 3 Participants | 2 Participants | 5 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 1 Participants | 2 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 2 Participants | 1 Participants | 3 Participants |
| Region of Enrollment United States | 3 Participants | 2 Participants | 5 Participants |
| Sex: Female, Male Female | 0 Participants | 0 Participants | 0 Participants |
| Sex: Female, Male Male | 3 Participants | 2 Participants | 5 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 3 | 0 / 2 |
| other Total, other adverse events | 0 / 3 | 0 / 2 |
| serious Total, serious adverse events | 0 / 3 | 0 / 2 |
Outcome results
Primary
Change in Carotid Total Plaque Volume From Baseline to Approximately 1 Year, as Assessed by Non-contrast MRI
The plaque characteristics will be analyzed by MRI-PlaqueViewTM (VP diagnostics Inc., WA). Planimetry will be performed on the image data sets, using histogram equalization to improve edge detection for plaque, arterial wall and lumen. Differences in image contrast between T1-weighted, T2-weighted, Time of Flight, and proton density will be used to characterize the plaque as fibrous, stable, or unstable.
Time frame: 1 year
Population: Since the study was terminated due to lack of enrollment and the paperwork to obtain the software to read the MRI was still being filled out, we did not have the software to analyze the MRI and thus there is no data to report.
Secondary
Characteristics of Plaques (Soft or Fibrous and Stable or Unstable) at Baseline and Upon Follow-up.
The plaque characteristics will be analyzed by MRI-PlaqueViewTM (VP diagnostics Inc., WA). Planimetry will be performed on the image data sets, using histogram equalization to improve edge detection for plaque, arterial wall and lumen. Differences in image contrast between T1-weighted, T2-weighted, Time of Flight, and proton density will be used to characterize the plaque as fibrous, stable, or unstable.
Time frame: 1 year
Population: Since the study was terminated due to lack of enrollment and the paperwork to obtain the software to read the MRI was still being filled out, we did not have the software to analyze the MRI and thus there is no data to report.
Secondary
Percentage of Total Plaque Area at Baseline and Upon Follow-up.
The plaque characteristics will be analyzed by MRI-PlaqueViewTM (VP diagnostics Inc., WA). Planimetry will be performed on the image data sets, using histogram equalization to improve edge detection for plaque, arterial wall and lumen. Differences in image contrast between T1-weighted, T2-weighted, Time of Flight, and proton density will be used to characterize the plaque as fibrous, stable, or unstable.
Time frame: 1 year
Population: Since the study was terminated due to lack of enrollment and the paperwork to obtain the software to read the MRI was still being filled out, we did not have the software to analyze the MRI and thus there is no data to report.
Secondary
Severity of Maximal Stenosis at Baseline and Upon Follow-up.
The plaque characteristics will be analyzed by MRI-PlaqueViewTM (VP diagnostics Inc., WA). Planimetry will be performed on the image data sets, using histogram equalization to improve edge detection for plaque, arterial wall and lumen. Differences in image contrast between T1-weighted, T2-weighted, Time of Flight, and proton density will be used to characterize the plaque as fibrous, stable, or unstable.
Time frame: 1 year
Population: Since the study was terminated due to lack of enrollment and the paperwork to obtain the software to read the MRI was still being filled out, we did not have the software to analyze the MRI and thus there is no data to report.