Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT04721262 |
| Other study ID # |
842634 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
November 9, 2020 |
| Est. completion date |
August 29, 2022 |
Study information
| Verified date |
December 2022 |
| Source |
University of Pennsylvania |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
The purpose of this pilot study is to evaluate the feasibility of using Ferumoxytol as a
contrast agent on a low field strength, portable magnetic resonance imaging (MRI) system.
Participants receiving Ferumoxytol as part of routine clinical care for iron deficiency
anemia will be recruited and scanned on the Hyperfine MRI system before and after their
clinically scheduled intravenous infusion. Resultant images will be compared to assess signal
intensity changes generated by the presence of Feromoxytol.
Description:
Ferumoxytol is a superparamagnetic iron oxide nanoparticle (SPION) preparation that was
originally designed as an MRI contrast agent, but later received FDA approval as a treatment
for iron deficiency anemia. Contrast agents alter MR images by changing tissue magnetic
relaxation constants such as T1 and T2 (or T2*). Gadolinium-based contrast agents decrease T1
values, causing increased signal on T1-weighted images. At low field strength, T1 values are
already very short so a further decrease may provide little contrast. At typical field
strengths, Ferumoxytol strongly decreases T1 and also T2 (and T2*) values, increasing signal
on T1-weighted images and (conversely) decreasing signal on T2-weighted images. This T2-based
contrast mechanism may be maintained at lower field strength.
Patients with iron deficiency anemia are commonly prescribed Ferumoxytol periodically as part
of their standard clinical care. Multiple studies have characterized the efficacy and safety
of Ferumoxytol in the treatment of iron deficiency anemia. Patients prescribed Ferumoxytol
for iron-deficiency anemia typically include otherwise healthy women with heavy menstrual
periods, patients with inflammatory bowel disease, and patients with chronic kidney disease.
Such patients make ideal candidates for characterizing the effects of Ferumoxytol on novel
imaging devices by obviating a medically unnecessary injection of the contrast agent.
Contrast agents play a key role in diagnosing and managing numerous diseases. Ferumoxytol has
been used to image a variety of pathologies and organs, including tumors and inflammation in
the brain, liver, pancreas, and prostate. In addition to the different magnetic relaxation
properties described above, Ferumoxytol has a higher molecular weight and prolonged blood
pool period compared to typical gadolinium-based agents, facilitating imaging vasculature
prior to the contrast agent leaking into the extravascular tissue. This has been exploited at
higher field strengths and may be particularly advantageous for low field imaging that
requires longer scan times. Ferumoxytol iron particles are taken up through the
reticuloendothelial system and added to physiologic iron stores, rather than being excreted
through the kidneys, resulting in increased plasma half-life while also avoiding concerns
related to impaired renal function that sometimes arise with other contrast agents.
The Hyperfine device is a newly developed MRI unit that has multiple potential advantages
over standard CT or MRI including portability, easier upkeep, open design, and ease of use.
Unlike CT, the Hyperfine device does not use moving parts or X-rays to generate images.
Unlike routine MRI, the Hyperfine device uses two permanent magnets with open space between
and around them, rather than a super-cooled superconducting magnetic tube. In contrast to CT
and routine MRI, the device can be wheeled from place to place and moved into position with
the patient remaining on a gurney or hospital bed. Relative to routine MRI, the device uses a
very low magnetic field strength of 64 mT compared to 1.5 T or 3 T, making it safer for
patients or environments with medical devices having metallic components.
Standard images of different types are obtained on the Hyperfine device at the push of a
button on an attached touch pad. Imaging protocols include those for anatomical depiction
such as balance steady-state free precession (bSFFP), T1-weighted (T1W) gradient echo (GRE),
and fast low-angle shot (FLASH) as well as imaging methods focused on the detection of
pathology and tissue damage such as diffusion-weighted imaging (DWI), fluid attenuated
inversion recovery (FLAIR), and T2-weighted (T2W) fast spin echo (FSE). However, it is not
known if existing contrast agents can provide effective contrast in the Hyperfine low-field
MRI.
Thus, the primary purpose of this study is to evaluate the efficacy of Ferumoxytol as a
contrast agent in low-field MRI scanners. Patients who are already receiving Ferumoxytol as a
treatment for iron deficiency anemia will be scanned before and after Ferumoxytol infusion.
Degree of contrast enhancement in intravascular and extravascular compartments including the
cerebral vasculature and the brain parenchyma will be the primary end-point for the study.
