Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT05959590 |
| Other study ID # |
13-621 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
Phase 1
|
| First received |
|
| Last updated |
|
| Start date |
February 12, 2014 |
| Est. completion date |
August 12, 2019 |
Study information
| Verified date |
December 2016 |
| Source |
University of New Mexico |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Diabetic foot infections contribute to 75,000 hospitalizations in the US each year. There is
a lifetime incidence of 15-25% of foot infections in diabetics. The investigators hypothesize
that ferumoxytol (FDA approved for use in CKD patients, unlike gadolinium) will improve the
accuracy of MR imaging in the diagnosis of osteomyelitis by allowing for the specific imaging
of macrophages that have taken up the iron-based compound. In this study the investigators
will image 12 patients with suspected diabetic osteomyelitis using ferumoxytol-contrasted
MRI, and evaluate the feasibility of this approach.
Description:
Prior to enrollment, patients will get baseline labs to ensure they are candidates for the
study. These will include a pregnancy test (if not previously acquired within 1 week of
enrollment in study), basic metabolic panel (if not already obtained within 48 hours of
enrollment), a complete blood count (if not already obtained within 48 hours of enrollment),
and a hemoglobin A1C (If not obtained within 4 weeks prior to enrollment).
MRI will be performed, and standard precautionary measures for MRI imaging will be followed.
Patients with a GFR below 40 or AKI (based on clinical suspicion in accordance with standard
UNM protocols for contraindications to gadolinium): Will obtain non-contrasted baseline MRI.
Within 72 hours of baseline MRI, patients will obtain ferumoxytol contrasted MRI (6
patients).
Patients with a GFR above 40 and no AKI: Will get an MRI with and without gadolinium contrast
on day 0 and ferumoxytol contrasted MRI within 72 hours (6 patients).
T1 with fat sat three planes, T2* and T2 with fat sat three planes will be obtained on a UNM
MRI machine. FLASH sequences will also be obtained.
24 hours after administration of ferumoxytol,a ferumoxytol-contrasted MRI will be performed
with the same acquisition parameters.
Ferumoxytol will be administered at a dose of 7 mg/kg up to 510 mg. The drug will be given as
an infusion over at least 15 minutes.
MRI images will be read and interpreted by at least one musculoskeletal radiologist as
diagnostic for osteomyelitis, diagnostic for not being osteomyelitis, or indeterminate based
on marrow enhancement. The images and their interpretations will be downloaded to PACS, where
researchers involved in the project will have access to the images. Signal intensity will be
recorded in areas of interest as determined by signal abnormalities on the MRI sequences.
Background noise will be measured in the area next to the area of interest. A signal to noise
ratio (SNR) will be calculated by dividing signal intensity by the background noise standard
deviation. The relative enhancement (RE) will be calculated by the equation: (SIpost -
SIpre)/SIpre x 100, where SIpost is the signal intensity 24 hours after administration of
contrast, and SIpre is signal intensity prior to administration of contrast.
Patients will be monitored in the hospital for at least 24 hours after administration of
ferumoxytol, obtaining vital signs every 4-8 hours.
The patient's CBC (complete blood count) and basic metabolic panel will be obtained on days 0
(the day of ferumoxytol administration), and 1 (the day of ferumoxytol-contrasted MRI
acquisition), monitoring specifically white blood count and creatinine.
Patients will be offered a follow-up appointment at the CTSC as indicated above. Follow up
imaging will be obtained during this visit as is clinically indicated. As described above, at
this time Dr. Unruh, Langsjoen and/or Dr. Neuwelt will decide if patient definitely had
osteomyelitis (which requires a tissue diagnosis), may have had osteomyelitis-won't be used
for accuracy calculations, or did not have osteomyelitis (based on tissue diagnosis or
clinical progression of the wound). The results of this decision will be used as a reference
standard. Bone biopsy and/or amputation will only be obtained as clinically indicated by the
primary medical team. Per standard protocols, it is likely that bone biopsy and/or
amputations will be obtained during the patient's inpatient hospital stay.
At this follow up visit at the CTSC, patient's charts will be reviewed to determine duration
of antibiotics administered and whether patient had bone biopsy and/or amputation (and
results).
Patients with a medical indication for bone biopsy will have this procedure within 72 hours
of ferumoxytol administration if this is medically indicated and feasible in order to
optimize scientific yield of the study.
Patients undergoing bone biopsy or amputation will have their tissues examined by pathology
faculty. Pathologists will analyze the specimen for evidence of osteomyelitis as well as
ferumoxytol content within the analyzed tissue (specifically noting presence within bone or
marrow), as determined by an anti-dextran monoclonal antibody (specific for the dextran
coating on ferumoxytol). Prussian blue stains will be obtained to measure iron content, and
specific stains for macrophages will also be performed. Tissues will be analyzed under the
direction of Dr. Bocklage at the UNM human tissue repository.
We also plan on performing quantitative studies to measure iron content and dextran content
within the tissues.
Ferumoxytol will be given to patients as an off-label drug as a contrast agent for MRI.
Ferumoxytol is FDA-approved for iron replacement in CKD patients.
