Patterns of use, effectiveness and safety of gadolinium contrast agents: a European prospective cross-sectional multicentre observational study

Evaluating Virtual Contrast-Enhanced Magnetic Resonance Imaging in Nasopharyngeal Carcinoma Radiation Therapy: A Retrospective Analysis for Primary Gross Tumor Delineation

PURPOSE

To investigate the potential of virtual contrast-enhanced magnetic resonance imaging (VCE-MRI) for gross-tumor-volume (GTV) delineation of nasopharyngeal carcinoma (NPC) using multi-institutional data.

METHODS AND MATERIALS

This study retrospectively retrieved T1-weighted (T1w), T2-weighted (T2w) MRI, gadolinium-based contrast-enhanced MRI (CE-MRI), and planning computed tomography (CT) of 348 biopsy-proven NPC patients from 3 oncology centers. A multimodality-guided synergistic neural network (MMgSN-Net) was trained using 288 patients to leverage complementary features in T1w and T2w MRI for VCE-MRI synthesis, which was independently evaluated using 60 patients. Three board-certified radiation oncologists and 2 medical physicists participated in clinical evaluations in 3 aspects: image quality assessment of the synthetic VCE-MRI, VCE-MRI in assisting target volume delineation, and effectiveness of VCE-MRI-based contours in treatment planning. The image quality assessment includes distinguishability between VCE-MRI and CE-MRI, clarity of tumor-to-normal tissue interface, and veracity of contrast enhancement in tumor invasion risk areas. Primary tumor delineation and treatment planning were manually performed by radiation oncologists and medical physicists, respectively.

RESULTS

The mean accuracy to distinguish VCE-MRI from CE-MRI was 31.67%; no significant difference was observed in the clarity of tumor-to-normal tissue interface between VCE-MRI and CE-MRI; for the veracity of contrast enhancement in tumor invasion risk areas, an accuracy of 85.8% was obtained. The image quality assessment results suggest that the image quality of VCE-MRI is highly similar to real CE-MRI. The mean dosimetric difference of planning target volumes was less than 1 Gy.

CONCLUSIONS

The VCE-MRI is highly promising to replace the use of gadolinium-based CE-MRI in tumor delineation of NPC patients.

Relationship of Dose and Signal Enhancement Properties of Gadoquatrane, a New Tetrameric, Macrocyclic Gadolinium-Based Contrast Agent, Compared With Gadobutrol: A Randomized Crossover Study in Healthy Adults

OBJECTIVES

To investigate the signal-enhancement properties of the tetrameric gadolinium-based contrast agent (GBCA) gadoquatrane in relation to the administered dose and compare its properties to those of a standard dose of gadobutrol, as a representative of the currently established macrocyclic GBCAs for magnetic resonance imaging.

MATERIALS AND METHODS

In this randomized, single-blind, 4 × 4 crossover study, 43 healthy adults (19-50 years of age) received 3 single IV injections of gadoquatrane (0.01, 0.03, and 0.06 mmol gadolinium/kg body weight) and 1 injection of gadobutrol (0.1 mmol gadolinium/kg body weight) in randomized sequence with 1-week washout periods between administrations. The relative signal enhancement (RSE) was determined in predefined areas of interest in magnetic resonance image sets of the head-neck region. RSE-vs-dose curves (dose-response curves) were established by linear regression, and comparator-equivalent doses were determined by Bayesian inverse regression analysis. Further, 3 blood samples were taken after each injection for pharmacokinetic analyses, and safety data were assessed.

RESULTS

The RSE increased with gadoquatrane dose. A linear function adequately fitted this relationship. In line with the more than 2-fold higher r1 relaxivity of gadoquatrane per gadolinium ion, gadobutrol-equivalent RSE was achieved with gadoquatrane at less than half the gadolinium dose and less than one eighth of the molecule dose.Administration of gadoquatrane and gadobutrol resulted in very similar dose-normalized gadolinium concentrations in plasma, indicating that the pharmacokinetic profiles are essentially the same. Both contrast agents were well tolerated. Adverse events were rare and not dependent on the dose administered.

CONCLUSIONS

Gadoquatrane has the potential to be an effective GBCA that can be used at substantially lower doses in clinical routine than the currently established macrocyclic GBCAs.

Pharmacokinetics, safety, and tolerability of the novel tetrameric gadolinium-based MRI contrast agent gadoquatrane in healthy Chinese and Japanese men: Two randomized dose-escalation studies including concentration-QTc modeling

PURPOSE

To investigate the pharmacokinetics, safety, and tolerability of the novel tetrameric high-relaxivity gadolinium-based contrast agent gadoquatrane in Japanese (Study 1) and Chinese men (Study 2).

PARTICIPANTS AND METHODS

In two similarly designed single-center, randomized, single-blind, placebo-controlled, consecutive-cohort dose-escalation studies, healthy volunteers were randomly assigned to intravenous administration of gadoquatrane (0.01-0.1 mmol gadolinium/kg body weight) or placebo. Study procedures included blood sampling and collection of urine for pharmacokinetic analyses and safety assessments.

RESULTS

Twenty-five healthy Japanese men (mean age ± standard deviation: 26±5.9 years) and 23 healthy Chinese men (31±7.6 years old) were evaluated. In both studies, the pharmacokinetic profile of gadoquatrane was characterized by rapid distribution of the drug into the extracellular space and fast renal elimination. Postdose gadolinium concentrations rapidly declined with a geometric mean effective half-life of 1.3-1.4 h. The exposure increased approximately dose-proportionally with dose. The body weight-normalized volume of distribution was constant across dose levels (0.21-0.24 L/kg). Total recovery of gadolinium in urine amounted to 82-95 % (Study 1) and 96-99 % (Study 2) of the dose administered. Only a few mild, transient adverse events were reported, none of which gave rise to any safety concerns. Exploratory drug concentration-QTc modeling indicated no risk of a clinically relevant QT/QTc prolongation at the anticipated diagnostic dose.

CONCLUSION

Gadoquatrane was safe and well tolerated at all doses tested. The pharmacokinetic profile was essentially the same as that of other extracellular macrocyclic gadolinium-based contrast agents and was consequentially also similar for Japanese and Chinese participants.

Safety, Tolerability, and Pharmacokinetics of a Novel Macrocyclic Gadolinium-Based Contrast Agent, HNP-2006, in Healthy Subjects

OBJECTIVES

Gadolinium-based contrast agents (GBCAs) are indispensable in contrast-enhanced magnetic resonance imaging. A higher risk of gadolinium deposition in linear GBCAs required the introduction of macrocyclic GBCAs with a stable molecular structure. We conducted the first-in-human study to evaluate the safety, tolerability, and pharmacokinetics (PKs) of HNP-2006, a novel macrocyclic GBCA, in healthy male subjects.

MATERIALS AND METHODS

A randomized, placebo-controlled, double-blind, single-ascending dose study was conducted. Subjects received either a single intravenous bolus injection of HNP-2006 or its matching placebo with a treatment-to-placebo ratio of 6:2 at the dose level of 0.02, 0.05, 0.1, 0.2, and 0.3 mmol/kg. Safety was assessed through routine clinical assessments. Blood sampling and urine collection were performed up to 72 hours postdose for PK assessments. Noncompartmental methods were used to calculate PK parameters, and a population PK model was constructed.

RESULTS

Overall, 40 subjects completed the study. Fourteen subjects reported 22 treatment-emergent adverse events (TEAEs). The severity of all TEAEs was mild, and the HNP-2006 dose was associated with the incidence of TEAEs. The most common TEAEs included nausea and dizziness, which occurred within an hour of administration. HNP-2006 was rapidly eliminated by urinary excretion with a half-life of 1.8-2.0 hours and showed a dose-proportional PK. A 2-compartment model had the best fit with the population PK analysis.

CONCLUSIONS

A single intravenous dose of HNP-2006 was well-tolerated and safe up to 0.30 mmol/kg. HNP-2006 was rapidly excreted in urine and exhibited dose-independent PK profiles.

Is non-contrast MRI sufficient to detect meningioma residue after surgery?

BACKGROUND

Contrast-enhanced magnetic resonance imaging (MRI) is the imaging modality routinely used to follow up patients who have undergone surgical resection of brain meningiomas. There are growing concerns about the massive use of gadolinium-based contrast agents (GBCA). Our aim was to evaluate the performance of a new imaging protocol, performed without GBCA injection, in the detection of tumoral residue or local recurrence after surgery of parafalcine and convexity meningiomas.

MATERIALS AND METHODS

Only adult patients with a documented resected parafalcine or convexity meningioma were included. We performed a dedicated MRI protocol that included non-contrast and post-contrast sequences. The presence or absence of residue on the unenhanced sequences was independently recorded by three observers: first blindly, then in comparison with a baseline enhanced MRI examination.

RESULTS

A total of 51 patients were included. 37 of them featured a tumor residue on the reference enhanced sequence. Overall, an average of 32 of 37 (87%) residues were identified on the unenhanced sequences that were blindly reviewed; and more than 34 of 37 (93%) were identified with the help of the comparative baseline enhanced examination, with a high sensitivity. The missed cases were related to small residues.

CONCLUSION

Unenhanced MRI sequences are highly sensitive and specific in identifying a tumor residue or a local recurrence in the post operative follow up of brain meningiomas. Sensitivity is even higher with the help of a comparative baseline enhanced MRI examination, whatever the strength of magnetic field.

MRI Gadolinium-Based Contrast Media: Meeting Radiological, Clinical, and Environmental Needs

Gadolinium-based contrast agents (GBCAs) are routinely used in magnetic resonance imaging (MRI). They are essential for choosing the most appropriate medical or surgical strategy for patients with serious pathologies, particularly in oncologic, inflammatory, and cardiovascular diseases. However, GBCAs have been associated with an increased risk of nephrogenic systemic fibrosis in patients with renal failure, as well as the possibility of deposition in the brain, bones, and other organs, even in patients with normal renal function. Research is underway to reduce the quantity of gadolinium injected, without compromising image quality and diagnosis. The next generation of GBCAs will enable a reduction in the gadolinium dose administered. Gadopiclenol is the first of this new generation of GBCAs, with high relaxivity, thus having the potential to reduce the gadolinium dose while maintaining good in vivo stability due to its macrocyclic structure. High-stability and high-relaxivity GBCAs will be one of the solutions for reducing the dose of gadolinium to be administered in clinical practice, while the development of new technologies, including optimization of MRI acquisitions, new contrast mechanisms, and artificial intelligence may help reduce the need for GBCAs. Future solutions may involve a combination of next-generation GBCAs and image-processing techniques to optimize diagnosis and treatment planning while minimizing exposure to gadolinium. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 3.

Gadolinium contrast agents- challenges and opportunities of a multidisciplinary approach: Literature review

Contrast agents is used in magnetic resonance imaging (MRI) to improve the visibility of the details of the organ structures. Gadolinium-based contrast agent (GBCA) has been used since 1988 in MRI for diagnostic and follow-up of patients, the gadolinium good properties make it an effective choice for enhance the signal in MRI by increase its intensity and shortening the relaxation time of the proton. Recently, many studies show a gadolinium deposition in different human organs due to release of free gadolinium various body organs or tissue, which led to increased concern about the use of gadolinium agents, in this study, the potential diseases that may affect the patient and side effects that appear on the patient and related to accumulation of gadolinium were clarified, the study focused on the organs such as brain and bones in which gadolinium deposition was found and the lesions associated with it, and the diseases associated with gadolinium retention includes Nephrogenic Systemic Fibrosis (NSF) and Gadolinium deposition disease (GDD). Some studies tended to improve the contrast agents by developing a new non-gadolinium agents or development of next-generation gadolinium agents. In this review article the latest knowledge about MRI contrast agent.

Dynamic 2-deoxy-D-glucose-enhanced multispectral optoacoustic tomography for assessing metabolism and vascular hemodynamics of breast cancer

Clinical tools for measuring tumor vascular hemodynamics, such as dynamic contrast-enhanced MRI, are clinically important to assess tumor properties. Here we explored the use of multispectral optoacoustic tomography (MSOT), which has a high spatial and temporal resolution, to measure the intratumoral pharmacokinetics of a near-infrared-dye-labeled 2-Deoxyglucose, 2-DG-800, in orthotropic 2-LMP breast tumors in mice. As uptake of 2-DG-800 is dependent on both vascular properties, and glucose transporter activity - a widely-used surrogate for metabolism, we evaluate hemodynamics of 2-DG-MP by fitting the dynamic MSOT signal of 2-DG-800 into two-compartment models including the extended Tofts model (ETM) and reference region model (RRM). We showed that dynamic 2-DG-enhanced MSOT (DGE-MSOT) is powerful in acquiring hemodynamic rate constants, including Ktrans and Kep, via systemically injecting a low dose of 2-DG-800 (0.5 µmol/kg b.w.). In our study, both ETM and RRM are efficient in deriving hemodynamic parameters in the tumor. Area-under-curve (AUC) values (which correlate to metabolism), and Ktrans and Kep values, can effectively distinguish tumor from muscle. Hemodynamic parameters also demonstrated correlations to hemoglobin, oxyhemoglobin, and blood oxygen level (SO2) measurements by spectral unmixing of the MSOT data. Together, our study for the first time demonstrated the capability of DGE-MSOT in assessing vascular hemodynamics of tumors.

Investigation of anthropogenic gadolinium in tap water of polish cities: Gdańsk, Kraków, Warszawa, and Wrocław

In urban areas where tap water is often produced by a purification of water supplied from a river bank filtration, a significant fraction of gadolinium (Gd) total pool is of an anthropogenic origin. It happens because Gd-based contrast agents used in Magnetic Resonance Imaging (MRI) are not removed during wastewater treatment and they are discharged to the environment and returned to the water cycle. Despite the growing number of MRI examinations worldwide, little is known about the anthropogenic Gd in Polish surface water as well as drinking water. The aim of this pilot study was to gain information about the occurrence of emergent pollution as Gd in potable water available for inhabitants of Polish municipal areas. Tap water samples from Gdańsk, Kraków, Wrocław and Warszawa were analyzed by an inductively coupled plasma quadrupole mass spectrometry after their preconcentration by a seaFAST-pico chromatographic system. In this study, the sum of REE was in the range registered in the drinking waters of European urban regions (usually below 100 ng/L). The highest values of the sum of REE total concentrations were observed in the tap water samples collected in Warszawa (37.7 ng/L) and Wrocław (35.9 ng/L and 32.9 ng/L), where water supplies originate from the Wisła River and Oława River, respectively. The highest total Gd concentration was observed in the tap water of Warszawa city where the anthropogenic Gd fraction represented about 90% of the total Gd. The lowest values of the sum REE were registered in tap waters of Gdańsk (sum of REE below 2.2 ng/L) with up to 17% of the anthropogenic Gd. Thus, our study showed the occurrence of the anthropogenic Gd in all analyzed tap waters.

Gadolinium-based contrast agents for imaging of the central nervous system: A multicenter European prospective study

Contrast-enhanced MR (CE-MR) imaging is required to improve lesion detection and characterization and to increase diagnostic confidence. This study aims to evaluate the safety, effectiveness, and usage patterns of recently introduced ClariscanTM (gadoterate meglumine) and other macrocyclic gadolinium-based contrast agents (GBCAs) used for magnetic resonance imaging (MRI) of the central nervous system (CNS). Data was obtained from a European multicenter, prospective, observational postmarketing study that included pediatric and adult patients undergoing contrast-enhanced MRI with a GBCA used in routine clinical practice. Safety data was collected by spontaneous patient adverse event (AE) reporting. Effectiveness was assessed via changes in radiological diagnosis, diagnostic confidence, and image quality. 766 patients with CNS-related indications were included from 8 centers across 5 European countries between December 2018 and November 2019. Clariscan (gadoterate meglumine) was used in 66% (503) of exams, Dotarem® (gadoterate meglumine) in 20% (160), Gadovist® (gadobutrol) in 13% (97), and ProHance® (gadoteridol) in 1%. GBCA use increased the diagnostic confidence in 95% (724/766) of patients and a change in radiological diagnosis in 65% (501/766) of patients. The Clariscan-specific data revealed an increase in diagnostic confidence in 94% (472/503) of patients and resulted in a change in radiological diagnosis in 58% (293/503) of patients. Image quality was considered excellent or good in 95% of patients across all GBCAs and in 94% of patients who received Clariscan. No AEs were reported in this cohort including Clariscan. This data demonstrates the excellent safety and efficacy profile of Clariscan and other GBCAs used in MRI examination of the CNS.

The Pattern of Use, Effectiveness, and Safety of Gadoteric Acid (Clariscan) in Patients Undergoing Contrast-Enhanced Magnetic Resonance Imaging: A Prospective, Multicenter, Observational Study

Objective

Contrast-enhanced MR (CE-MR) imaging is often required to improve lesion detection and characterization and to increase diagnostic confidence. This study aimed to evaluate the safety and effectiveness, as well as the use pattern, of the macrocyclic gadolinium-based contrast agent Clariscan in real-world clinical practice in Korea.

Materials and Methods

This was a prospective, multicenter, observational study of patients undergoing CE-MR as part of routine clinical care at 6 university hospitals in Korea. Effectiveness was evaluated by determining diagnostic confidence and image quality; safety evaluation included the adverse event (AE) expression rate. Subgroup analyses were conducted by body regions of diagnosis (musculoskeletal, nervous system, others) and in pediatric patients (aged ≤7 years).

Results

From October 2019 to September 2020, 1,376 subjects were included in the study. The mean volume of Clariscan used was 0.26 mL/kg (0.13 mmol/kg). In the overall study population and in each subgroup, diagnostic confidence increased after contrast enhancement with Clariscan. Overall, image quality was excellent in 72.5% of subjects and good-to-adequate in 27.2%. Clariscan was well tolerated (14 AEs occurred in 10 subjects); all AEs were of mild severity. Subgroup analyses showed that the mean dose of Clariscan used was ≥0.1 mmol/kg for nervous system-related diagnoses (e.g., brain) and ≤0.1 mmol/kg for musculoskeletal and pediatric-related diagnoses. All musculoskeletal and pediatric examinations were provided with a smaller package of 5 mL Clariscan. By body region of MR examination, the most common region was the nervous system in 69.0%, musculoskeletal system in 13.6%, and reproductive system in 4.9%.

Conclusions

This study confirmed the use pattern of Clariscan and its excellent effectiveness and safety in the real-world clinical environment in Korea. The small-dose package indicated the possibility of increasing the convenience and efficiency of drug use.