Quantifying the Perturbation of Gadoxetate Kinetics by Metformin and Ciclosporin With Functional Magnetic Resonance Imaging of the Liver
Conditions: Liver Dysfunction
Sponsor: Sheffield Teaching Hospitals NHS Foundation Trust

 
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Quantifying the perturbation of gadoxetate 
kinetics by metformin and ciclosporin with 
functional magnetic resonance imaging of 
the liver. 
 
  
  
Study protocol 
Version 1.12       06 February 2025 
 
 
 
 
 

 
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Research Protocol  
  
Full Title: Quantifying the perturbation of gadoxetate kinetics by metformin and 
ciclosporin with functional magnetic resonance imaging of the liver. 
 
Short Title: Assessing changes in gadoxetate metabolism by the liver using MRI 
 
Study Sponsor: Sheffield Teaching Hospitals NHS Foundation Trust 
 
Investigators: 
● Sheffield Teaching Hospitals 
○ (Clinical Lead and principal investigator) Benjamin Rea (Consultant GI 
radiologist and honorary senior lecturer) 
● University of Sheffield 
○ (University Lead) Steven Sourbron (Professor of imaging physics) 
● Bioxydyn Ltd 
○ Geoff Parker (Founder) 
○ John Waterton (Translational Imaging Specialist) 
  
Estimated Duration of Study:   
● 3 months 
○ Start Date: 30.9.24   
○ End Date: 28.02.25 
  
Number and Type of Participants: 
● Enrolment 
○ 12 healthy volunteer participants (6 for each of metformin and 
ciclosporin groups) 
● Sex 
○ Equal number of males and females for each drug 
● Age Range 
○ ≥ 18 years 

 
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Synopsis 
 
Background 
 
The identification of drugs at risk of drug-drug interactions (DDI) early in the drug 
development life cycle is key to avoid late stage drug development failures. A 
critical gap in current methodologies is for tools that are widely available and safe to 
use in humans, and specifically can distinguish between perturbation of 
hepatocellular uptake, excretion or both.  
 
Dynamic gadoxetate enhanced magnetic resonance imaging (DGE-MRI) is a 
technique that can potentially fill this gap. The MRI contrast agent gadoxetate is 
used in clinical routine, it is known to be taken up in hepatocytes by transporters 
OATPB1 and excreted to bile by MRP2 transporters, and the respective uptake and 
excretion rates can be quantified with DGE-MRI using suitable MRI scans and data 
modelling.  
 
Studies in animal models using DGE-MRI on 6 different drugs have clearly 
demonstrated various levels of drug-induced inhibition of gadoxetate uptake and 
excretion (Karageorgis, 2018; Melillo, 2023). Recently, a proof-of-concept study in 
healthy human volunteers using DGE-MRI to characterise a single drug (rifampicin) 
has shown a systematic 95% reduction in gadoxetate uptake and 40% reduction in 
excretion. 
 
Aims 
 
Study objectives 
The purpose of the current study is to expand on these previous results and use 
DGE-MRI to measure the inhibition of gadoxetate uptake and excretion in 
volunteers with two other test drugs, metformin and ciclosporin (Neoral). These 
drugs are selected because they are commonly used in clinical practice, have a 
good safety profile and are known to inhibit OATP1B1 and MRP2 function (Ruan, 
2023; Gertz, 2013). They should therefore also produce a      measurable effect on 
gadoxetate uptake and excretion rates. If we can show that this is indeed 

 
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measurable, the results will add further evidence that these effects can be detected 
by DGE-MRI, improve our understanding of relevant effect size and limits of 
detection, and help us identify thresholds above which reduction in gadoxetate 
uptake or excretion would be of concern. 
 
Study endpoints 
1. The effect of a clinical dose of metformin on hepatocellular gadoxetate uptake 
and excretion in healthy volunteers. 
2. The effect of a clinical dose of ciclosporin (Neoral) on hepatocellular gadoxetate 
uptake and excretion in healthy volunteers. 
 
Long-term aims 
On the longer term we expect these data to help build a case that DGE-MRI can be 
a useful tool to assess transported-mediated DDI risk in early drug development. 
The study results will be included in an application to FDA’s biomarker qualification 
program as described in a biomarker qualification plan (submitted to FDA) following 
acceptance by the FDA of a letter of intent outlining the rationale for this biomarker 
in drug development. 
 
Methods 
 
This is a single centre, prospective observational study including healthy volunteer 
participants. 6 participants will be recruited to each immediate-release metformin 
and ciclosporin (Neoral) drug arms (12 total). After screening and consent, each 
subject will attend two hospital visits. On each visit they will undergo DGE-MRI in 
the morning, and once again after a 2-hour break to allow for sufficient time to 
measure biliary gadoxetate clearance. On the second visit one of the two test drugs 
will be administered before the first scan.  Each DGE-MRI scan will be performed 
using 25% (¼) of a clinical dose of gadoxetate. Immediate-release metformin and 
ciclosporin (Neoral) will be used at standardised dosages (1000mg and 100mg, 
respectively). Blood samples will be taken before drug administration and before 
each scan for comparative assessment with liver function tests (LFT). 
 
A schema of this work is outlined below and in Figure 1: 

 
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1. Visit A, Screening: After eligibility screening, informed consent for 
participation will be taken.  A clinical examination including observations and 
blood tests for renal and liver function will be taken.  If renal function shows 
eGFR<30mL/min/1.73m2, liver function parameters exceed laboratory 
normal values or clinical examination findings are not compatible with the 
inclusion criteria, the participants will be removed from the study. 
2. Visit B, Baseline Scan: Participants will have two DGE-MRI scans with 
25% (¼) standard clinical dose of gadoxetate administered at each. Blood 
samples (<5mL) will be taken before each scan to assess liver function.   
3. Visit C, Treatment Scan: After giving informed consent, participants will 
receive a single dose of either metformin or ciclosporin (Neoral) followed by 
an initial DGE-MRI scan at 25% (¼) standard clinical dose of gadoxetate.  
Metformin (1000mg) or ciclosporin (100mg, Neoral) will be administered 2 
and 1 hour before gadoxetate injection, respectively.  This is followed by 
another DGE-MRI at the same dose after a break of 60-120 minutes. LFTs 
(<5mL blood) will be taken before metformin/ciclosporin (Neoral) 
administration, and also before each scan (totalling 3 blood tests). 
 
 
 
 
  
 
Figure 1. Study flow diagram.

 
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Analyses 
 
All images will be reviewed by a qualified abdominal radiologist to check for 
incidental findings.  
 
Gadoxetate uptake and excretion kinetic rate constants will be measured with and 
without the drug for all participants. The primary outcome measure is the effect size 
of the drug on uptake and excretion. 
 
The primary analyses will be done at the University of Sheffield. 
 
Safety 
 
The modelling and use of gadoxetate as a research biomarker was established in 
the proof-of-concept study conducted at the University of Leeds. Gadoxetate will be 
used at 25% (¼) standard clinical dose for each scan. This dose was established in 
the precursor study as the requisite dose to enable analyses of gadoxetate kinetics 
whilst not exposing participants unnecessarily to higher doses of the gadoxetate. At 
25% of standard clinical dose, gadoxetate is not licensed for the diagnostic use. 
The administration of gadoxetate will be authorised by the clinical lead, Dr 
Benjamin Rea. 
 
Both Metformin and Ciclosporin have an excellent safety profile and record, and 
therefore the risk posed to a healthy volunteer with no history of polypharmacy or 
comorbidities from a one off dose, is negligible. Routine clinical exclusions will be 
applied pertaining to the administration of gadoxetate, metformin and ciclosporin 
(Neoral) as well as contraindications to MRI imaging.   
 
There will be no monitoring procedures undertaken following completion of this 
study but the research fellow will remain contactable following completion of the 
study for further queries. 
 

 
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Table of contents 
 
  
Table of contents 
7 
1. Background 
111.1 The TRISTAN project
 
10 
1.2 Motivation 
11 
1.3 Hypothesis 
13 
1.4 The DGE-MRI assay 
14 
2. Study Objectives 
18 
2.1. Study aims 
18 
2.2. Endpoints 
20 
2.3 Long-term aim 
20 
3. Design summary 
21 
3.1 Recruitment 
22 
3.2 Visit A - Screening/consent visit 
22 
3.3 Visit B - Baseline visit 
23 
3.4 Visit C - Treatment visit 
24 
3.5 Monitoring procedures 
24 
4. Sample size estimation 
25 
5. Participant Selection Criteria 
25 
5.1 Inclusion criteria 
25 
5.2 Exclusion criteria 
2266. Participant Procedures
 
26 
6.1 Overview of study visits 
26 
6.2 Recruitment 
2286.3 Visit A - Screening/Consent visit
 
2296.4 Visit B - Baseline Scan
 
2306.5 Visit C - Treatment scan
 
29 
7. Data and Sample Collection 
31 
7.1 Preparation 
31 
7.2 Clinical information 
3327.3 Blood Samples Collection and storage
 
31 
7.4 MRI scanning 
31 
8. Data analysis 
3338.1 Outcome measures
 
32 
8.1.1 Primary outcome measures 
32 

 
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8.1.2 Secondary outcome measures 
3348.2 Statistical analysis
 
33 
9. Risks 
33 
9.1 MRI scanning 
34 
9.2 Contrast agent and medications 
34 
9.2.1 Gadoxetate (Primovist®) 
3359.2.2 Metformin
 
3369.2.3 Ciclosporin
 
36 
9.2.4 Cannulation and Venepuncture 
38 
9.3 Incidental findings 
38 
9.4 Nosocomial infections 
39 
9.5 Urgent Safety Measures 
39 
9.6 Safety Reporting of Serious Adverse Events (SAEs) 
40 
10. Study documentation 
40 
10.1 Study protocol 
40 
10.2 Recruitment advertisement 
41 
10.3 Screening questionnaire 
41 
10.4 Participant Information Sheet (PIS) 
44210.5 Consent form
 
41 
10.6 MR screening form 
42 
11. Data management 
44311.1 Confidentiality and personal data
 
44311.1.1 Recruitment forms
 
42 
11.1.2 Screening questionnaire 
44411.1.3 Consent form
 
44411.1.4 MR screening forms
 
43 
11.1.5 Key file 
43 
11.2 MRI data management 
44 
11.3 Data backup and external use 
44511.4 Publications and presentations
 
45 
11.5 Long-term data storage 
446 
11.6 Withdrawal from the study 
45 
11.7 End of Study 
44612. References
 
46 
13. Appendix 
5113.1 Serious adverse event reporting form
 
50 
13.2 REC reporting form 
52 
 

 
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1. Background 
  
1.1 The TRISTAN project   
This study is part of an international project TRISTAN (Translational Imaging in 
Drug Safety Assessment), which receives funding from the Innovative Medicines 
Initiative 2 Joint Undertaking under grant agreement No 116106. This Joint 
Undertaking receives support from the European Union’s Horizon 2020 research 
and innovation programme and the European Federation of Pharmaceutical 
Industries and Associations (EFPIA). The primary aim of TRISTAN is to develop 
and validate imaging biomarkers for drug safety assessment.  
 
Currently, imaging biomarkers are not widely used in the drug discovery process 
although they could advance drug safety evaluation, both for pre-clinical and clinical 
development. They have the potential to improve translatability of preclinical 
(animal) data to healthy volunteers and patients and thus could help avoid late 
stage attrition of development programmes. In addition, functional diagnostic 
imaging methods used as biomarkers would offer the possibility to confirm drug 
toxicity mechanisms in humans, including the potential to determine drug-drug 
interactions (DDI’s). 
  
TRISTAN (www.imi-tristan.eu) is a public-private partnership involving 21 
organisations including academic centres, research organisations, small and 
medium-size enterprises (SMEs), imaging and pharmaceutical companies which 
form the Consortium under the consortium agreement. The collective objective is to 
validate or qualify translational imaging methods as potential imaging biomarkers, 
specifically addressing three areas with a high unmet medical need - the 
assessment of liver toxicity, lung toxicity and the bio-distribution of biologics.  
  
The project is organised in five work packages - WP1 orchestrates management, 
communication, dissemination and ethics; WP2 aims to develop a DGE-MRI 
biomarker assay for early identification of possible drug-drug interactions (DDIs); 

 
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WP3 aims to develop imaging biomarkers for drug-induced interstitial lung disease 
(DIILD); WP4 aims to characterise the bio-distribution of biologics; and WP5 will 
define a roadmap for dissemination of the imaging biomarker assays. The current 
study is organised by TRISTAN WP2. 
1.2 Motivation 
Many hundreds of licensed drugs may cause undesired interactions with co-
administered victim drugs (DDIs) or drug induced liver injury (DILI).  DDIs can result 
in potentiated or reduced efficacy that requires drug dose adjustment, and/or 
increased or reduced toxicity to liver or other tissues, for example muscle toxicity 
caused by statins (Guo et al., 2018).  DILI may result in severe symptomatic liver 
injury and/or life-threatening acute liver failure (Andrade et al., 2019) and is a 
consequence of adverse effects of drugs on liver function, plus susceptibility factors 
that in general are poorly understood.   For all but a few drugs the frequency of 
human DILI is low liver injury is not evident in animal safety studies.  This is likely to 
be because the susceptibility factors arise only infrequently and unpredictably 
(Andrade et al., 2019).   Consequently, DILI typically is not recognised prior to Phase 
3 clinical trials, or post-marketing. 
 
One important mechanism that can initiate both DDIs and DILI      is perturbation by 
drugs of the activities of membrane transport proteins on hepatocytes.  For example, 
inhibition of the hepatic uptake transporter OATP1B1 by a co-administered 
perpetrator drug may impair clearance of statins and lead to elevated plasma and 
systemic tissue exposure, resulting in myotoxicity (Guo et al., 2018).  Conversely, 
interaction of perpetrator drugs with hepatic transporters that mediate biliary 
excretion may alter hepatocyte exposure to a victim drug without causing a 
measurable effect on systemic plasma exposure (e.g., metformin DDIs due to 
OCT2/MATE inhibition) (Galetin et al., 2017).  The hepatocyte transporter interaction 
proposed to play a role in DILI initiation is the Bile Salt Export Pump (BSEP).  BSEP 
mediates excretion of bile salts from hepatocytes into bile and genetically inherited 
defects in human BSEP expression are known to cause severe cholestatic liver 
injury, which arises because elevated bile salt concentrations within hepatocytes 
cause cell toxicity (Kubitz et al., 2012).  Many drugs which cause DILI inhibit BSEP 

 
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activity and it has been proposed that prospective screening for BSEP inhibition in 
drug discovery has the potential to aid early identification and deselection of drugs 
that have the propensity to cause human DILI, prior to clinical trials (Kenna et al., 
2018).  
 
Although various in vitro methods can be used to quantify inhibition of hepatocytes 
transporters (Shin et al., 2017; Du et al., 2017; Metry et al., 2022), currently it is 
unclear how the data provided by these assays can be used to assess the in vivo 
human DILI or DDI risk posed by investigational drugs. This is because the in vitro 
methods do not provide adequate insight into drug exposure or interplay of multiple 
processes as seen in vivo, while the biomarkers of liver toxicity evaluated in in vivo 
drug safety studies (plasma ALT and bilirubin in animals and humans, plus liver 
histopathology in animals) do not provide insight into the activity of hepatic 
transporters. 
 
Currently, DDIs are assessed non-clinically via in vitro studies in a variety of cellular 
systems. Quantitative translation of in vitro data to in vivo is undertaken via 
physiologically-based pharmacokinetic (PBPK) modelling, which integrates in vitro 
transporter kinetic/inhibition data with relevant in vivo physiological parameters.  
PBPK models simulate changes in both systemic and tissue exposure of the victim 
drug, which arise as a result of changes in enzyme and/or transporter activity caused 
by the perpetrator drug [Guo et al., 2018; Galetin et al., 2017; FDA (A), 2018; FDA 
(B), 2020; FDA (C), 2020Guidance Document, 2020; PBPA Guidance for Industry).  
 
In the development of an investigational drug (ID), PBPK analyses of such animal 
and cell studies often suggest that the ID may be a transporter inhibitor or inducer in 
man, and thus carry an enhanced DDI risk.  In such cases, clinical studies of the 
impact of the perpetrator drug on plasma exposure of a victim drug are an early 
priority in drug development.  Such a package of non-clinical and clinical studies is 
used routinely to support regulatory submissions and drug labelling and the value 
has been recognized in recently published DDI and PBPK regulatory guidance 
documents (FDA (A), 2018; FDA (B), 2020; FDA (C), 2020)[Guidance Document i, 
2020; PBPA Guidance for Industry; Guidance Document ii, 2020].   
 

 
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However, verification of the accuracy of PBPK simulations is challenging, especially 
for transporter DDIs that arise due to changes in drug exposure within hepatocytes 
but not in plasma.  Furthermore, clinical DDI studies are unable to detect DDIs which 
arise via inhibition of MRP2 and result in increased liver exposure to victim drugs, 
but not in detectable elevation of plasma drug concentration.  Consequently, clinical 
trials have been shown to run the risk of either underestimating DDIs, and so 
potentially harming study subjects, or of failing to show sufficient drug efficacy 
because of overestimation of potential DDIs and poorly informed lowering of the drug 
dose ([FDA (A), 2018; FDA (C), 2020PBPA Guidance for Industry; Guidance 
Document ii, 2020; Rodrigues, 2019).   
 
1.3 Hypothesis 
 
To address this important drug development need, we are assessing the value of a 
widely available quantitative biomarker modality: dynamic gadoxetate enhanced 
magnetic resonance imaging (DGE-MRI). Currently the technology is used widely to 
characterise and diagnose human liver abnormalities.   
 
Gadoxetate is excreted extensively by both liver and kidneys (Leyendecker et al., 
2009). Hepatic excretion is known to occur via uptake into hepatocytes, which is 
mediated primarily via hepatocellular uptake by OATPs and to a lesser extent NTCP 
(Leonhardt, 2010), then MRP2-and MRP3-mediated excretion from hepatocytes into 
bile (Saito et al., 2013).  With suitable dynamic MRI scan protocols, coupled to 
dedicated modelling of the data (see next section), gadoxetate liver uptake and 
excretion rates can be measured quantitatively. In principle, this novel liver imaging 
biomarker pair could be used in drug development to aid assessment of DDI risk 
arising from effects of test drugs on activities of transporters that mediate hepatocyte 
uptake and efflux of gadoxetate (i.e., OATP1B1, OATP1B3, NTCP, MRP2 and/or 
MRP3).   
 
Previously, we and others have shown in rats that gadoxetate DGE-MRI can be used 
to assess and quantify kinetic rate constants for gadoxetate transport from the 

 
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extracellular space into hepatocytes (k(he)) and from hepatocytes into bile (k(bh)); 
and also to quantify the effects on the rate constants of 6 different test drugs which 
inhibit hepatobiliary transporters (Ulloa et al., 2013; Karageorgis et al., 2018; 
Georgiou et al., 2017; Scotcher et al., 2021; Melillo et al., 2023; Weinmann et al., 
1996; Leonhardt et al., 2010; Jia et al., 2014).   
 
In addition, we undertook a study in healthy volunteers given one of the test drugs 
(rifampicin). The study has shown a systematic 95% reduction in uptake and 40% 
reduction in excretion, which has provided proof-of-principle that the method can be 
used to quantify effects on human hepatocyte transporter function in vivo (Min et al., 
2023).  This work further ascertained gadoxetate, administered at 25% (¼) standard 
clinical dose, provides sufficient images on DGE-MRI to facilitate quantitative, kinetic 
assessment of DILI in those who had a single dose of rifampicin. 
 
Since gadoxetate is not a substrate of BSEP, we do not consider that DGE-MRI will 
provide data that are likely to be informative of DILI risk, but instead is most suited to 
assessment of hepatocyte transporter mediated DDI risk. 
 
1.4      The DGE-MRI assay 
The specific structure of gadoxetate concentration-time profiles in the liver are 
reflective of the rate of liver uptake and excretion. There is typically a rapid initial 
uptake corresponding to the extracellular phase followed by a slower increase 
corresponding to intracellular uptake (Figure 2). With sufficiently long acquisition 
times, the curve shows a decrease due to biliary excretion. Biliary excretion typically 
occurs after approximately 20 minutes (commonly known as the hepatobiliary phase 
in diagnostic liver imaging).  In diagnostic imaging this would produce the typical 
dynamic arterial, portal venous, transitional phase and hepatobiliary phase images 
as outlined in figure 3.  
 
These diagnostic images are evaluated by visual inspection and do not produce 
quantitative measurements of gadoxetate uptake and excretion rates. In order to 
achieve quantification, rapid dynamic imaging is required to produce an accurate 

 
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assessment of the actual kinetic profiles, including rapid changes during the 
extracellular phase of the agent’s distribution. For this reason, 3D images designed 
for quantitative analysis need to be acquired about every 3 seconds, which naturally 
comes with some penalty in terms of image quality. Moreover, since gadoxetate 
uptake and especially excretion are slow processes, this rapid imaging needs to be 
performed for at least 30 minutes, but significantly longer when liver function is 
impaired and gadoxetate elimination is correspondingly delayed. While 30 minutes 
may be adequate in a normal liver, our simulations have shown that, in order to 
detect a reduction of 90% in biliary excretion, images must be acquired over a time 
scale of at least 2 hours after administration of the inhibitor. Since this is not feasible 
in a single MRI scan, the protocol developed for this purpose involves two separate 
MRI scans, separated by approximately 60-90 minutes. This is not feasible for 
diagnostic purposes in clinical practice, but in early drug development where critical 
decisions are made, such studies are well justified. 
 
The analysis of the images involves motion-correction of the MRI images to remove 
breathing motion, contouring of the liver and aorta to extract signal-time curves and 
MRi signal modelling to derive gadoxetate concentrations. These are then 
interpreted by fitting to a dedicated liver kinetic model (figure 4), producing the 
uptake rate khe and excretion rate kbh by fitting the model to the data. An example 
of the signal-time curves for aorta and liver, along with their model fits, is shown in 
figure 5. This example is taken from the proof-of-concept study with rifampicin in 
Leeds. The effect of rifampicin on the liver signal is clearly visible with the naked 
eye, showing a significant reduction in the signal after the initial extracellular phase. 
The quantitative analysis has revealed that this is explained by a 90% reduction in 
uptake rate, and 40% reduction in excretion. 
 

 
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Figure 2 - dynamic contrast phases with gadoxetate (Ao = aorta, HAs = hepatic 
artery, PVs = portal veins, HVs = hepatic veins, AP = arterial phase, PVP = 
portal venous phase, HBP = hepatobiliary phase) 
 
Figure 3 - overview of MRI imaging phases pre and post gadoxetate 

 
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Figure 4 – Diagram of the 6-parameter kinetic model used to derive gadoxetate 
uptake and excretion rates from rapidly sampled concentration-time curves. The 
model uses an aorta concentration as input, and further consists of one 
compartment for the gut, one compartment for the liver’s extracellular space and one 
for the hepatocytes.  
 

 
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Figure 5. Signal-time curves along with model fits, for one volunteer of the proof-of-
concept study at baseline (left column) and after rifampicin (right column) for the 
aorta (top row) and the liver (bottom row). Each plot shows the measured signal data 
for the two scans (red dots) and with the model fit (blue line). The X-axis shows the 
time since the start of the first scan in seconds. 
 
2. Study Objectives  
2.1. Study aims 
 
The purpose of the current study is to expand on the proof-of-concept study with 
rifampicin and use DGE-MRI to measure the inhibition of gadoxetate uptake and 
excretion in volunteers with two other test drugs, metformin and ciclosporin (Neoral). 
These drugs are selected because they are commonly used in clinical practice, have 
a good safety profile and are known to inhibit OATP1B1 and MRP2 function (Ruan, 

 
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2023; Gertz, 2013). The results will add further evidence that these effects can be 
detected by DGE-MRI, improve our understanding of relevant effect size and limits of 
detection, and help us identify thresholds above which reduction in gadoxetate 
uptake or excretion would be of concern. In the longer term, establishing the 
sensitivity of gadoxetate rate constants would further strengthen our case that DGE-
MRI can be used as a screening tool in drug development, to establish the impact of 
novel drugs on hepatic transporter function and the associated risk of DDI. Since 
DGE-MRI is a costly and time-consuming modality, a secondary objective of the 
study is to compare the effect size of the DGE-MRI biomarkers against that of 
standard liver function tests. If the results confirm that gadoxetate rate constants are 
more specific and more sensitive to drug effects than widely available LFT’s, this 
would further strengthen the case for the use of DGE-MRI in this setting. The 
baseline values for the LFT’s also act as an independent verification that the liver 
function of the study subjects is in the normal range.  
 
Ciclosporin and metformin are chosen as test drugs because their kinetics is well 
characterised, they are commonly used in clinical routine and carry strong safety 
profiles.Ciclosporin is a potent inhibitor of hepatic uptake via interactions with OATP, 
in particular cyclosporin A is a time-dependent inhibitor of OATP1B1 with long-
lastingness (Melillo et al., 2023; Izumi et al., 2015). In addition, ciclosporin is a potent 
inhibitor of MRP2 (Yang et al., 2020). Metformin does not interact with OATP, but 
instead with MRP2.; its Inhibition of MRP2 has been shown to impair biliary 
clearance of drugs such as atorvastatin, suggesting a possible mechanism for the 
unpredictable effects of statins on liver function. This impairs biliary excretion and 
increases liver concentration, without measurably affecting plasma concentration of 
the victim drug  (Shin et al., 2017).   
 
Ciclosporin and metformin are commonly used in clinical practice and carry strong 
safety profiles. Neither metformin nor cyclosporin accounted for any adverse drug 
reactions as cause for hospital admission in a large, multicentre study, a finding 
which was reproduced in a more recent, smaller study (Pirmohamed et al. 2004; 
Osanlou et al. 2021). In a randomised double-blind clinical trial, no significant safety 
concerns were noted when using metformin in 18,000 patient-years of follow-up (The 

 
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Diabetes Prevention Programme Research Group, 2012). Similarly, low-dose 
cyclosporin has been shown to be safe, even when used long-term (Di Leo et al. 
2011). When considering these studies were performed in patients on long term 
prescriptions with comorbidities, the safety data from these trials provides 
reassurance that they are safe drugs to use as a one-off dose in healthy subjects. 
 
2.2. Endpoints 
 
Primary: 
 
1. The effect of a clinical dose of metformin on hepatocellular gadoxetate uptake 
and excretion in healthy volunteers. 
2. The effect of a clinical dose of ciclosporin (Neoral) on hepatocellular gadoxetate 
uptake and excretion in healthy volunteers. 
 
Secondary: 
 
1. Compare effect size of gadoxetate uptake and clearance rates as measured by 
DGE-MRI with liver function test results in response to test drug administration. 
2.The effect size of the drug on secondary imaging measures such as relative 
enhancement ratio or area under the curve in blood and liver concentrations. 
3. Diurnal variations in uptake and excretion rates in the absence of an intervention 
(baseline data) 
 
 
2.3 Long-term aim 
 
On the longer term we expect these data to help build a case that DGE-MRI can be 
a useful tool to assess transported-mediated DDI risk in early drug development.  
 
The TRISTAN consortium has been engaging with the FDAs biomarker qualification 
program for several years now, and in January 2021 reached a major milestone 

 
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when the FDA officially accepted the letter of intent (LoI) outlining the definition, 
assay and intended use of gadoxetate uptake and excretion rates as a biomarker 
for drug safety studies (https://www.fda.gov/media/149415/download).  
 
In December 2023 the TRISTAN consortium submitted a biomarker qualification 
plan (BQP), describing a collection of experiments that have been and will be 
performed to support a full qualification application. The BQP included the proof-of-
concept study in Leeds, a currently ongoing patient study, and the 2-compound 
study described in this protocol. In august 2024 another major milestone was 
reached when the FDA formally classified the BQP as reviewable, meaning the 
agency will invest time and resources for a detailed review and feedback within 6 
months.  
 
After revision and final acceptance of the BQP, the final step in the process will be 
a full qualification submission. The results derived in this study will be included in 
that submission as a critical step towards formal approval of these novel 
biomarkers for use as a drug safety marker in early stage drug development. 
 
3. Design summary 
This study is an observational study of gadoxetate-enhanced MRI as a putative 
imaging biomarker of drug transporter function in the liver. The overall design is 
summarised in Figure 1. 
 
All study procedures will be done at Sheffield Teaching Hospitals NHS Foundation 
Trust at the Royal Hallamshire Hospital (RHH) site.  This is the site for University of 
Sheffield MRI related research.  All scanning will be performed on the 3T University 
MRI scanner and images will be anonymised and transferred securely to the 
University of Sheffield network for analysis.  Participant understanding and consent 
will be checked at each visit. 
 

 
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3.1 Recruitment 
Six healthy volunteer participants will be recruited to each drug arm (3 men and 3 
women for each drug).  Participants will be recruited via an advert on the internal 
University of Sheffield Medical School platform ‘Minerva’ and on 
callforparticipants.com.  Participants will be recruited on a first come first serve 
basis with only a contact email collated at this point.  Following email confirmation 
of their interest by the research fellow, the participant information sheet (PIS) will be 
provided for them to read, informing them of the risks and benefits of the study, and 
the requirements of them throughout.  A unique Study ID will be generated for the 
participant.  A further screening form will be sent to the participant which will 
ascertain their eligibility to participate and collate any pertinent information.  The 
form will be associated with their unique Study ID and no personal nor identifiable 
information will be collected. 
3.2 Visit A - Screening/consent visit 
Eligibility screening will be performed through the verification of their responses.  The 
PIS will be reviewed with the participant in detail to ensure they understand the risks 
and benefits of the study along with the requirements of them. A consent form will be 
  
 
Figure 1. Study flow diagram.

 
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completed. Participants will undergo clinical examination with observations 
(respiratory rate, oxygen saturations, blood pressure, heart rate, temperature). A 
blood test to assess renal and liver function will be taken. If the renal function blood 
test shows eGFR<30mL/min/1.73, markers of liver function exceed laboratory normal 
values or if the clinical examination does not meet inclusion criteria, the participant 
will be removed from the study and will not be counted towards the study target.  
Blood markers of liver function for this study are aspartate transaminase (AST), 
alanine transaminase (ALT), alkaline phosphatase (ALP), gamma-
glutamyltransferase (GGT) and bilirubin. Any abnormal results will be communicated 
to the participant and with their permission, the participant’s general practitioner.  
3.3 Visit B - Baseline visit 
Two DGE-MRI scans will be performed with gadoxetate given at 25% (¼) standard 
clinical dose.  The duration of each scan will be approximately 60-75 minutes. 
There will be a between-scan interval break for the participants of between 60 and 
120 minutes.  
 
The research fellow, prior to the scan, will insert an intravenous cannula to the 
participant’s arm to draw blood samples (5mL each) for liver function before each 
scan, and to administer a contrast agent during the scan.  
 
After the baseline visit and before the next visit, the scan data will be analysed, 
specifically assessing image quality and implementation of the PBPK model of 
gadoxetate kinetics.  Two outcomes are possible: 
1. The image quality and PBPK modelling is satisfactory.  The 
participant will proceed to Visit C within 56 days and have DGE-MRI 
scanning repeated following metformin or ciclosporin (Neoral) 
administration. 
2. The image quality or PBPK modelling is insufficient.  In this case, the 
cause of this will be reviewed by the senior research team and the 
participant will be removed from the study. 

 
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3.4 Visit C - Treatment visit 
Participants will now enter the arm of the study which they were recruited for, to 
receive either metformin or ciclosporin (Neoral).  They will undergo two DGE-MRI 
scans using the same dosage of gadoxetate and imaging protocol used in Visit B.  
Participants will have a set of observations and a clinical examination performed 
before administering the medication and be excluded if found to have uncontrolled 
hypertension or an active infection. 
 
Participants will receive either a single oral dose of 1000mg immediate-release 
metformin or 100mg ciclosporin (Neoral).  Ciclosporin (Neoral) will be given 1 hour 
before gadoxetate administration. Metformin will be given 2 hours before 
gadoxetate administration.  Following this initial scan, the participant will be given a 
60-120 minute break after which a second DGE-MRI scan will be performed.  Each 
scan will take 60-75 minutes with a maximum total scan time of 150 minutes at this 
visit. 
 
The research fellow will perform venepuncture on arrival, before metformin or 
ciclosporin (Neoral) administration, for a liver function blood test.  Prior to each 
scan the research fellow will insert an intravenous cannula to the participant’s arm 
for the administration of contrast agent.  At each insertion, a blood sample for liver 
function will be taken (totalling 3 blood tests at this visit, or 5mL each). 
 
Total dosage of gadoxetate administered across all visits is 100% standard clinical 
dose and will not be exceeded. 
3.5 Monitoring procedures 
 
There will be no participant monitoring procedures undertaken following completion 
of the Visit C but the research fellow will remain contactable for further queries. 

 
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4. Sample size estimation  
The proof of concept study at the University of Leeds performed previously in this 
research stream used a minimum sample size of 6 participants. This matched the 
sample size of previous animal studies in which the reduction of hepatic gadoxetate 
uptake following rifampicin administration was approximately 50% compared to the 
control.  
 
Using data from the human proof of concept study, a new analysis showed that the 
minimal number of subjects needed to demonstrate an inhibition in uptake and 
excretion of 20% or more (a typical cutoff for DDI risk in drug development) with 
95% confidence was 4 subjects per drug. The number was increased to 6 per drug 
to allow for drop-outs after the first visit or scan failures (which happened in 3/20 
scans in the pilot study) and allow for an equal number of men and women per 
drug.   
5. Participant Selection Criteria 
5.1 Inclusion criteria 
● Able to provide informed consent 
● Age above 18 years 
● Able to attend for all scheduled visits 
● Able to adhere to instructions on pre-scan food and drinks intake 
● Able to lie flat for the duration of the scan 
5.2 Exclusion criteria 
Standard MRI exclusions, including: 
● No history of liver or kidney disease 
● No history of heart failure 
● No history of uncontrolled hypertension 
● No history of malignancy or premalignant conditions, past or present 
● No current uncontrolled infections 

 
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● Not currently pregnant 
● Not currently breastfeeding 
● No regular prescribed medication, except the oral contraceptive pill 
● Cochlear implant 
● Aneurysm clips 
● Neurological stimulator 
● Implanted cardiac devices (ICD, PPM, loop recorders, or any others) 
● Metal heart valve 
● History of retained metal foreign bodies 
● Other implanted metal device which prevents MR imaging 
● Claustrophobia 
● Weight exceeding 140 kg 
● History or allergic reaction to MRI contrast agent  
6. Participant Procedures 
6.1 Overview of study visits 
 
Participants will undergo study visits as outlined below and in Figure 1: 
  
● Recruitment 
● Visit A - Pre-Screening/Consent visit with pre-scan renal function blood test 
● Visit B - Baseline scan visit 
● Visit C - Treatment scan visit            
 
All study visits will be face-to-face at Sheffield Teaching Hospitals, RHH site and 
DGE-MRI scans will be performed on the University of Sheffield MRI scanner at the 
same site.  Understanding of the research procedures will be checked at each visit 
and consent taken again. 

 
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6.2 Recruitment  
Participants will be recruited via two methods.  An advert will be placed on the 
University of Sheffield Medical School internal platform ‘Minerva’ which medical 
students and staff use.  There will be a link to an online form to complete which will 
confirm they have read the entry requirements and will collect only their email.  A 
further advert will be placed on www.callforparticipants.com with the same 
information and will again confirm that the participant meets the entry requirements 
and collect their email. 
 
The email of the research fellow will be on the advertisement for any participants 
wishing to contact the team directly.  After expressing interest, the participant will 
receive an email from a research fellow inviting them to a screening visit and will be 
asked to respond with a suitable time.  If a participant does not respond initially, a 
further email will be sent.  If there is no response following this email, the participant 
will be removed from further consideration and their email will be deleted. 
 
On agreeing an appointment for the screening visit, a unique Study ID will be 
generated for the participant.  The research fellow will provide the participant with 
the PIS and will ask the participant to study this prior to the agreed meeting.  
Participants will be given at least 72 hours to consider the information in the PIS 
before the meeting.  A further screening online form will be sent to the participant 
which will ascertain their eligibility to participate and collate any pertinent 
information. The form will be associated with their unique Study ID and no personal 
nor identifiable information will be collected. 
 
Participants will be remunerated by a £150 flat-rate given to participants after 
completion of all scans and £75 after completion of one scan visit.  A standardised, 
free lunch will be given to participants, with flexibility to adapt to any dietary 
requirements. In addition, travel expenses will also be reimbursed up to the amount 
of £50. All expenses will be paid in cash. This will be on the advertisement and in 
the PIS. 

 
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6.3 Visit A - Screening/Consent visit  
A research fellow will verify the responses of the screening online form with the 
participant face-to-face to ensure the participant meets eligibility criteria and is safe 
to proceed. Female participants of child-bearing potential will have a urine 
pregnancy test performed to detect human chorionic gonadotropin (HCG) in their 
urine. A negative HCG result will confirm a non-pregnancy status and will be used 
to exclude unsuspecting pregnant participants from enrolling onto the study.         
  
The research fellow will then explain the study in detail and review the PIS with the 
participant, outlining that progression through the study is not guaranteed 
dependent on biochemical and imaging results.  This will be done in accordance 
with the requirements of the ethics review and human subject research regulations.  
The written comprehensive consent documents will be reviewed.  Participants will 
be asked to provide consent for the blood tests and MRI scans as well as to store 
and share their anonymised MRI images for future research.  Written consent will 
be obtained.  
 
The research fellow will take a set of observations (respiratory rate, oxygen 
saturation, blood pressure, heart rate and temperature) and perform a clinical 
examination.  Participants will be excluded if found to have uncontrolled 
hypertension or active infection.  The research fellow will also perform 
venepuncture to assess the participant’s renal and liver function.  If the renal 
function blood test shows eGFR<30mL/min/1.73, markers of liver function (as 
outlined in 3.2) exceed laboratory normal values or if the clinical examination does 
not meet inclusion criteria, the participant will be removed from the study and will 
not be counted towards the study target. The abnormal blood test or clinical 
examination will be communicated to the participant and with their permission, the 
participant’s general practitioner. 
 
The screening/consent visit will last no more than 30 minutes with an addition of 10 
minutes if blood sampling is done in the same setting. 
 
On completion of the above, dates for Visit B and Visit C will be agreed. 

 
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6.4 Visit B - Baseline Scan   
Participants will undergo two DGE-MRI scans and two blood tests during this visit.  
Participants will be asked to attend having fasted for at least 4 hours before the 
time of the scan.  Participants will be counselled to only drink water prior to the 
scan.  An MRI screening form will be completed in accordance with local practice.  
Participant’s height and weight will also be recorded. Female participants of child-
bearing potential will have a urine pregnancy test performed to detect human 
chorionic gonadotropin (HCG) in their urine. A negative HCG result will confirm a 
non-pregnancy status and will be used to exclude unsuspecting pregnant 
participants from the risk of the dye. Pregnancy tests will be provided . 
 
A research fellow or experienced radiographer will insert an intravenous cannula 
into the participant’s arm for the administration of contrast agent during the 
examination.  At this time, a blood sample will be taken (5mL) and sent for 
assessment of liver function. 
  
There will be two DGE-MRI scans with a gadoxetate injection at 25% (¼) standard 
clinical dose at each. Gadoxetate will be injected at 60 seconds into the first scan 
acquisition and at 10 minutes into the second.  Each scan will take approximately 
60 to 75 minutes with a maximum total scan time of 150 minutes at this visit. There 
will be an interval break for the participants of between 60 and 120 minutes in 
which a standardised lunch will be provided. 
 
The participant will be asked to remain still on his/her back throughout the duration 
of the scan. The staff will maintain constant communication with the participants in 
between image acquisitions.  Participants will be able to decide to stop and 
withdraw from the scan at any time.  If this is the case, scanning will be stopped 
and the participant will be removed from the study. 
 

 
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6.5 Visit C - Treatment scan 
Participants will be asked to attend having fasted for at least 4 hours before the 
time of the appointment.  An MRI screening form will again be completed in 
accordance with local practice.  Participant information including height and weight 
will also be recorded.   Participants will have a repeat set of observations 
(respiratory rate, oxygen saturation, blood pressure, heart rate and temperature) 
and a clinical examination.  Participants will be excluded if found to have 
uncontrolled hypertension or an active infection. Female participants of child-
bearing potential will have a urine pregnancy test performed to detect human 
chorionic gonadotropin (HCG) in their urine. A negative HCG result will confirm a 
non-pregnancy status and will be used to exclude unsuspecting pregnant 
participants from the risk of the dye and drug. Pregnancy tests will be provided. 
 
A blood test for liver function will be taken via venepuncture by the research fellow 
before administering the drug.  Before each scan, the research fellow or 
experienced radiographer will insert an intravenous cannula to the participant’s arm 
for the administration of contrast agent during the examination. At this time a blood 
sample will be taken (5mL) for liver function tests using the same cannula (totalling 
3 samples, 15ml).   
 
The participants will take either 1000mg immediate-release metformin or 100mg 
ciclosporin (Neoral) orally with water and remain fasted until the MRI scan.  For 
ciclosporin, gadoxetate will be administered 1 hour after ingestion. For metformin, 
gadoxetate will be administered 2 hours after ingestion.  Two DGE-MRI scans will 
be performed with a gadoxetate injection at 25% (¼) standard clinical dose at each. 
Gadoxetate will be injected at 60 seconds into the first scan acquisition and at 10 
minutes into the second.  Each scan will take approximately 60 to 75 minutes with a 
maximum total scan time of 150 minutes at this visit. There will be an interval break 
for the participants of between 60 and 120 minutes.   
 
The participant will be asked to remain still on his/her back throughout the duration 
of the scan. The staff will maintain constant communication with the participants in 

 
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between image acquisitions. Participants will be able to decide to stop and 
withdraw from the scan at any time. 
 
Participants will not receive greater than a standard clinical dose of gadoxetate in 
total across both Visit B and C of this study. 
7. Data and Sample Collection 
7.1 Preparation 
Volunteers will be required to prepare for each scan as follows:  
● 72 hours prior to the day of the scan 
○ Abstain from drinks containing alcohol            
● On the day of the scan 
○ Fast for 4 hours before Visit B and C 
7.2 Clinical information 
The following information will be acquired prior to each scan: 
●  Documentation of:   
○ Height 
○ Weight 
● Standard MR screening form 
7.3 Blood Samples Collection and storage 
Blood samples will be taken for screening renal function and liver function taken 
during screening (Visit A), baseline (Visit B) and treatment (Visit C) visits as 
outlined in 6.4 and 6.5 respectively. All of the plasma samples will be destroyed 
when the study ends. Blood samples for liver and renal function will be processed 
routinely as per Sheffield Teaching Hospitals laboratory policy.  

 
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7.4 MRI scanning 
The lead investigator will coordinate with the radiography team who operate the 
University of Sheffield MRI scanner to book slots for participants and inform them of 
the protocol.  The research fellow will liaise with participants and the radiography 
team to organise scanning as per the protocol.  Up to 30 breath-holds of up to 12 to 
17 seconds each may be required.  There will be periods of free breathing scans 
between different breath-hold scans, giving the participants several rest periods. 
The protocol is specified in detail in SOPs provided and maintained by TRISTAN 
partner Bioxydyn, including quality assurance measures and radiographer training. 
8. Data analysis 
Analysis of MRI data will be done according to the study design. The imaging data 
will be quality reviewed scan by scan after Visit B to ensure that adequate scans are 
being obtained for quantitative analysis. 
 
Images will be processed by the research team on encrypted University of Sheffield 
computers using custom-written software to perform breathing motion correction,  
and segment the liver and aorta. Signal-time curves will be extracted as csv files and 
processed using custom-made python scripts to extract measurements of 
gadoxetate uptake rate (khe, mL/min/100mL) and gadoxetate excretion rate (kbh, 
mL/min/100ml) for each subject and for each visit. An effect size will be determined 
for each subject and for each rate constant. This will serve as main outcome 
measures: 
 
Effect size (%) = 100* (rate constant with drug - rate constant without drug)/(rate 
constant without drug) 
 
Statistical analysis of gadoxetate kinetics will only commence after all the scans in 
Visit C have been completed.   

 
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8.1 Outcome measures 
8.1.1 Primary outcome measures 
 
The primary outcomes of interest are to: 
1. 95% CI on the mean effect size of uptake rate khe 
2. 95% CI on the mean effect size of excretion rate kbh 
 
Gadoxetate kinetics will be described under a bespoke and previously validated 
physiologically-based pharmacokinetic (PBPK) model where both uptake and efflux 
rates can be calculated.  Additional imaging parameters will be described to mirror 
the previous animal and human studies, including the relative enhancement of the 
liver following gadoxetate administration and T1 values pre and post gadoxetate 
administration. 
8.1.2 Secondary outcome measures 
The secondary outcomes of interest are: 
1. Compare effect size of gadoxetate uptake and clearance rates as measured 
by DGE-MRI with liver function test results in response to test drug 
administration. 
2. The effect size of the drug on secondary imaging measures such as relative 
enhancement ratio or area under the curve in blood and liver concentrations. 
3. Diurnal variations in uptake and excretion rates in the absence of an 
intervention (baseline data) 
 
 
8.2 Statistical analysis 
The average effect size of all 6 subjects will be determined for each drug, as well as 
the 95% confidence interval on the mean (mean +/- 1.96*sdev/sqrt(6)). The drug 
will be considered to pose a DDI risk if the 20% threshold falls outside of the 95% 
CI for mean khe or kbh effect size. 
 

 
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An independent analysis of the findings will be conducted by Bioxydyn, the study 
collaborator. 
9. Risks  
There are a number of risks of differing likelihoods associated with undertaking this 
observational study which are outlined below.  All this information will be made 
available to participants prior to enrolling in the study. 
9.1 MRI scanning 
MRI scans do not involve any radiation and are safe and painless. There are no 
known risks to this technique as long as standard MR exclusion criteria are satisfied. 
Some people may experience claustrophobia in an MRI scanner. The scan can 
however be stopped at any time, at the participant’s request. The MRI staff will 
monitor the participant via a video camera and an audio link. The participant can 
also pull out of the study or scan at any time. Participants will be required to do 
breath holds as standard MRI scanning protocol to improve quality of images. 
9.2 Contrast agent and medications 
Allergic reactions are rare but possible in gadoxetate, metformin and ciclosporin.  
Equipment and treatments are immediately available at RHH should a reaction occur 
with an on-call medical team on site.  Specific risks associated with each are outlined 
below. 
9.2.1 Gadoxetate (Primovist®) 
 
Gadoxetate is an intravenous contrast agent used extensively in clinical imaging 
studies of the liver.  Gadoxetate is safe but there are a number of known adverse 
effects.  Headache and nausea are commonly reported but are transient.  A feeling 
of breathlessness is also reported at a rate of approximately 1 in 100 persons 
administered this contrast agent.  It should be used with caution in those with renal 
impairment, due to the risk of nephrogenic systemic fibrosis. Therefore, a pre-scan 
renal function blood test will be performed during the study. If the renal function 

 
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blood test shows eGFR<30mL/min/1.73, the participant will not be eligible for the 
study. The incidental abnormal results will be communicated to the participant and 
with their permission, the participant’s general practitioner. 
 
Gadoxetate is a gadolinium salt and there are reports of accumulation of gadolinium 
in the brain of persons administered this agent (Murata, 2016(A); Murata, 2016(B))  
There are no reports of any clinical sequelae as a consequence of this accumulation 
and gadoxetate is widely used in clinical practice for the assessment of focal liver 
lesions. 
 
Gadoxetate will be used at 25% (¼) standard clinical dose per scan, meaning that 
with a maximum of four MRI examinations, each person will receive 100% of a 
standard clinical dose overall.  This will not be exceeded and if imaging is not 
sufficient for kinetic analysis, the participant will not undergo any repeat imaging 
and be excluded from the study. 
 
The administration of gadoxetate will be authorised by the clinical lead, Dr 
Benjamin Rea. 
9.2.2 Metformin 
Metformin is an antihyperglycaemic medication authorised for use in the treatment 
of type 2 diabetes mellitus.  It is given orally and comes in immediate-release and 
modified-release preparations.  The immediate-release preparation starts at a dose 
of 500mg and can be uptitrated to 2g daily in three divided doses, taken at meal 
times.  The modified-release preparation starts again at a dose of 500mg and can 
be uptitrated to 2g in two divided doses, at morning and evening meals.  This study 
will use 1000mg immediate-release metformin to match previous literature on 
metformin DDIs (Hibma, 2016). 
 
Metformin is a well established diabetic medication that has been used clinically for 
over 50 years. Adverse effects of treatment are known and are more commonly 
experienced with immediate-release preparations and if not taken with food.  
Common adverse effects include abdominal pain, decreased appetite, diarrhoea, 

 
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nausea, altered taste, vitamin B12 deficiency and vomiting.  These side effects are 
most common on initiating the medication and resolve spontaneously on cessation.  
More rare and severe adverse reactions including skin reactions, hepatitis and 
lactic acidosis.  The manufacturer advises caution in those at risk of lactic acidosis 
including those with chronic stable heart failure and other medications that are 
known to impair renal function.  Therefore, inclusion criteria requires participants to 
have no history of heart failure and no regular prescribed medications. 
 
Metformin has been reported to inhibit MRP2 activity in vitro and in rats in vivo 
(Shin et al., 2016). In a rat DGE-MRI study, metformin administration reduced the 
rate of gadoxetate efflux from the liver but did not alter the rate of gadoxetate 
uptake, indicating functional inhibition of MRP2 but not OATP transport activity in 
vivo (Melillo et al., 2023). 
 
However, overall metformin has an excellent safety profile.  In two large studies 
looking at the medications responsible for patients being admitted with adverse 
drug reactions (ADR), metformin was not responsible for any of the 1443 ADR 
related admissions (Pirmohamed et al., 2004; Osanlou et al., 2021).  The first study 
(Pirmohamed et al., 2004) in particular looked at 19920 patient admissions, and the 
two major risk factors for ADR identified from these studies were polypharmacy and 
multimorbidity.  Given our proposed study would by using healthy volunteers who 
other than the OCP would not be on any regular medication, any risk to the 
participants would be mitigated.  Additionally, given Metformin was not responsible 
for any ADR related admission despite being a commonly prescribed medication in 
patients that often have established risk profiles (cardiovascular disease, obesity, 
metabolic syndrome) the risk to a healthy volunteer participant from a one of dose 
is negligible.  
 
9.2.3 Ciclosporin 
Ciclosporin is an immunosuppressant medication authorised for use in the treatment 
of many immune-mediated diseases such as rheumatoid arthritis, psoriasis, 
inflammatory bowel disease and to prevent rejection in organ transplantation.  It can 

 
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be administered orally or intravenously.  The dosage is calculated based on the body 
weight ranging from 1.25mg/kg to 15mg/kg as single or divided doses depending on 
the indication.  This observational study will use a standardised dosage of 100mg.  
This dose was determined to match previous literature on ciclosporin DDIs 
(Kajosaari, 2005).  This will be in the Neoral formulation as others have different 
bioavailability and different DDIs. 
 
Contraindications include malignancy, uncontrolled hypertension and uncontrolled 
infections.  These will be screened for before enrollment and participants will have a 
set of observations (respiratory rate, oxygen saturation, blood pressure, heart rate 
and temperature) and a clinical examination performed before administering the 
medication in Visit C.  Those with uncontrolled hypertension and active infection will 
be excluded at this point. 
 
Common adverse effects include eye inflammation, decreased appetite, diarrhoea, 
electrolyte imbalance, fatigue, fever, flushing, gastrointestinal discomfort, gingival 
hyperplasia, hair changes, headaches, hyperglycaemia, hyperlipidaemia, 
hypertension, hyperuricaemia, leucopenia, muscle complaints, nausea, 
paraesthesia, peptic ulcer, renal impairment (renal structural changes on long-term 
administration), seizure, skin reactions, tremor, vomiting.  Uncommon and rare 
adverse effects include anaemia, encephalopathy, oedema, thrombocytopenia, 
increased weight, gynaecomastia,haemolytic anaemia, idiopathic intracranial 
hypertension, menstrual disorder, multifocal motor neuropathy, muscle weakness, 
myopathy and pancreatitis. 
 
Ciclosporin is reported to be a potent in vitro inhibitor of multiple hepatocyte uptake 
and efflux transporters, which include both OATP1B and MRP2 (Izumi et al., 2015; 
Yang et al., 2020).  In a rat DGE-MRI study, ciclosporin administration markedly 
reduced the rate of gadoxetate uptake into the liver and also biliary excretion from 
the liver, demonstrating functional inhibition of both OATP and MRP2 transport 
activity in vivo (Melillo et al., 2023). 
 
Ciclosporin is a long established immunosuppressant medication.  In the 
aforementioned large UK based studies analysing admissions due to ADR, as with 

 
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Metformin, Ciclosporin was not attributed to be the cause of any ADR admission. 
(Pirmohamed et al., 2004; Osanlou et al., 2021).  As an immunosuppressant 
Ciclosporin necessitates an excellent safety profile, and therefore the risk posed to a 
healthy volunteer with no history of polypharmacy or comorbidities from a one off 
dose, is once again negligible. 
9.2.4 Cannulation and Venepuncture  
Intravenous cannulation would be required for administration of gadoxetate prior to 
MRI scan. This will be done by an experienced radiographer or research fellow.  
Where possible, a blood sample will be taken off a cannula on initial insertion.  For 
subsequent blood sampling, venepuncture will be required as blood sampling from 
a used cannula will cause erroneous results and increase risk of cannula-related 
infection. This will also be done by an experienced radiographer or research fellow.  
A blood test will check for pre-scan renal function blood test to ensure that this is 
normal due to the risk of nephrogenic systemic fibrosis on administration of 
gadoxetate in those with renal impairment. If the renal function blood test shows 
eGFR<30mL/min/1.73, the participant will be excluded from the study.  Additional 
blood tests will check for liver function.  The cannula will only remain in situ for the 
MRI scan. After the cannula removal or following venepuncture, there may be 
bruising and discomfort that may persist for a few days which should settle 
spontaneously. 
 
There is a small risk of needlestick injury which will be minimised by the 
experienced radiographer or research fellow following local sharp safety measures.  
If a needlestick injury were to occur, local policy on initial actions will be followed 
and the occupational health department will be contacted to advise on further 
measures required. 
9.3 Incidental findings 
To look for incidental findings, images will be reviewed by Dr Rea, a consultant in 
gastrointestinal and abdominal radiology.  Any abnormal blood results will further 
be reviewed by a research fellow using local lab parameters. For any unexpected 
abnormal finding related to the MRI scan, this will be reviewed by an expert liver 

 
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radiologist (Dr B Rea). If necessary, a clinical report will be issued. All clinically 
relevant incidental findings will be communicated back to the participants’     
General Practitioner with the participants’ permission          .  In rare cases, the 
results will also be communicated to a clinical hepatologist. This process will be 
discussed and explained to the participant during the consent visit. 
9.4 Nosocomial infections 
There is a risk of hospital-acquired (nosocomial) infections upon attending RHH.  
These infections are commonly viral in nature, most likely a seasonal virus (causing 
the common cold) or SARS-CoV-2 (COVID-19).  The morbidity and mortality 
associated with COVID-19 has significantly decreased from its peak in early 2021.  
Both public health and local hospital restrictions have eased accordingly.  Other 
viral infections such as influenza show yearly seasonal peaks in Autumn and Winter 
(UKHSA, 2024).  We will closely adhere to national Public Health England and local 
Sheffield Teaching Hospitals infection control policies to minimise the risk of 
hospital-acquired infection for the participants.  Precautions include but are not 
limited to: regular hand washing, frequent surface decontamination and ventilation.  
 
Visits will be limited to one participant per session and participants will be allocated 
a pre-secured MRI time slot to avoid unnecessary waiting or infective contacts.  
The clinical areas used at RHH do provide acute inpatient services but for the 
purposes of this study, participants will be confined to the radiology department, 
reducing potential exposures.  
 
The cohort of participants are healthy volunteers, aged 18 years or over without 
other health concerns. This may reduce the additional risk of contracting or 
developing a severe infection. 
9.5 Urgent Safety Measures 
The Sponsor or Chief Investigator may take appropriate urgent safety measures 
with the intention of protecting research participants against any immediate harm to 
their health or safety.  
 

 
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The event will be reported within three days to the Research Ethics Committee 
(REC), that such measures have been taken, the indication for such measures and 
plan for further actions. 
9.6 Safety Reporting of Serious Adverse Events (SAEs) 
A serious adverse event (SAE) is defined as an untoward occurrence that:  
● results in death;  
● is life-threatening;  
● requires hospitalisation or prolongation of existing hospitalisation;  
● results in persistent or significant disability or incapacity; or  
● consists of a congenital abnormality or birth defect; or  
● is otherwise considered medically significant by the investigator.  
Any adverse events relating to this study will be reported and managed internally at 
Sheffield Teaching Hospitals. In the unlikely scenario that a SAE is unexpected and is felt 
to be related to a study procedure, the event will be reported to the Research Ethics 
Committee. The SAE will be reported to the sponsor within 1 working day of the 
research team’s awareness of the event.  To alert the sponsor, a serious adverse 
event reporting form (see appendix 13.1) will be completed and reported to the 
Director of Research, Partnerships & Innovation and Research Ethics & Integrity 
Manager whose contact details are available here. 
Furthermore, REC will be made aware within 15 days of the Principal Investigator 
becoming aware of the event and will be reported through the non-CTIMP safety 
report to REC form available here (see appendix 13.2).   
10. Study documentation  
10.1 Study protocol  
The protocol describes the background and purpose of the study, explains which 
procedures will be done and why, and details how the results will be utilised and 
interpreted. 

 
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10.2 Recruitment advertisement 
The same advert will be posted on Minerva and callforparticipants.com as outlined in 
6.2.  The advert will outline the study, the participants role and the eligibility criteria.  
Potential participants will be asked to confirm they have read the eligibility criteria 
and enter their email address to allow the research fellow to contact them.  No other 
information will be collated at this point. 
10.3 Screening questionnaire 
The screening questionnaire is filled in by a research fellow during Visit A 
(screening/consent visit) to confirm eligibility of the participant for the study. 
Questions relate to MRI safety, general health and past medical history. The 
questionnaire does not include any identifiable information about the potential 
participant. If, at the end of the screening visit, the participant declines to volunteer 
for the study, the questionnaire will be destroyed.  On giving consent for inclusion in 
the study, the participant’s questionnaire will be marked with their unique Study ID 
for future reference. 
10.4 Participant Information Sheet (PIS)  
The Participant Information Sheet contains information on the study relevant to an 
interested participant. It explains the purpose of the study, what is expected of the 
participant and the associated risks and benefits. It is given to the participant on 
agreeing a date to complete Visit A (screening visit), at least 72 hours beforehand. 
During the screening visit, the participant may ask any questions about the study 
and address any concerns, allowing them to make an informed choice on 
volunteering for the study.  During the course of the study, the PIS will also serve 
as a personal record for each volunteer, showing their Study ID and details of their 
completed and upcoming scans.  
10.5 Consent form  
At the time of the screening visit, once all study details have been explained and 
understood, the participant will be asked to sign a consent form. This will be written 
(not electronic) consent.  Through the above measures and the PIS, the participant 

 
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will make an informed decision on their inclusion in the study.  Written consent will 
be obtained at each visit to ensure understanding is maintained. 
10.6 MR screening form 
These questionnaires review standard MR exclusion criteria as outlined in 5.2. 
They will be given to the participant by the site radiographer and will be stored 
according to local procedures using anonymised study IDs. 
11. Data management 
All      data collated or generated during this research study will be stored short term 
on an encrypted shared Drive (administered by university IT) with only the 
investigators and research fellows having access. This data may need to be 
analysed on systems such as PACS or proprietary software for incidental findings 
assessment, liver segmentation and gadoxetate kinetic assessment but data will be 
removed from these systems on completion of the relevant analysis. 
 
Upon completion of the research activities all data will be deleted from this short term 
storage and will be stored, fully anonymised, in a long-term repository as outlined in 
11.5. 
11.1 Confidentiality and personal data 
Volunteers will be assigned an anonymous, unique Study ID after consenting to be 
included in the study. All data collected for research purposes will only be linked to 
their Study ID. Other data captured on the scanner includes date of birth, height 
and weight. This data will be handled securely in line with local practice. The link 
between anonymous study ID and the participants real identity will be stored 
exclusively in a single key file that will be stored securely on STH premises.  
 
11.1.1 Recruitment forms 
The online form used to collate participants via Minerva will be created by a research 
fellow stored on the shared encrypted University of Sheffield Google account and will 

 
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only be accessible by those in the research group.  No personal information and only 
an email will be collected to allow the research fellow to contact those interested.  
 
A callforparticipants.com advert will be used which does not have access to 
participant responses and no data will be sent to third parties.  No personal 
information and only an email will be collected to allow the research fellow to contact 
those interested.   
11.1.2 Screening questionnaire 
Following email confirmation of a participant’s interest to be included, a Study ID will 
be generated for them.  A further online form will be provided to participants to 
screen for their eligibility prior to Visit A.  No personal identifying information will be 
collected and all responses will be associated with the participants Study ID.  This 
document will be digital only and stored on the shared encrypted University of 
Sheffield Google Drive account. 
11.1.3 Consent form 
Participant written consent forms will contain their names and signatures. On the day 
of the study, these forms will be securely stored in the University MRI scanner room 
(with restricted entry) at the RHH site. The Sheffield Teaching Hospitals radiology 
department and University MRI suite is of restricted entry with swipe card access 
requiring appropriate security clearance. At the end of each visit, the forms will be 
scanned and uploaded to the encrypted, shared research group Sheffield Teaching 
Hospitals  Drive.  All paper copies will be archived for 5 years within STH premises. 
11.1.4 MR screening forms 
MR screening forms will be stored locally in accordance with local clinical practice. 
All paper copies will be archived for 5 years within STH premises. 
11.1.5 Key file 
A digitally encrypted key file, linking Study ID to participant names, date of birth and 
contact details, will be stored on the local STH drives, separate from all other study 
data. The key file will be securely stored for 5 years at the end of the study, after all 

 
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MRI scans on all participants have been completed. In the event that a participant 
withdraws from the study and requests their data and information to be removed, 
their entry in the key file will be used to identify and remove their data.  
11.2 MRI data management 
At the end of each scan, MRI data will be exported anonymously using the 
participant’s Study ID. Anonymised MR images will be exported in DICOM (Digital 
Imaging and Communication) format to the shared encrypted research group 
University of Sheffield Google Drive for primary analysis. Data for primary analysis 
will be performed with in-house software on an encrypted University of Sheffield 
computer. 
 
University MR Data is archived on the MRI unit (UniPACS) and transferred to the 
secure University XNAT network and servers, where it can be stored, archived and 
processed. These servers have secure access and serve as an imaging informatics 
software platform.  Dr Rea will review the images for incidental findings using this 
system only and all data will be removed from this system after the review. 
11.3 Data backup and external use 
 
All      data collected or generated through this study will be anonymised with the 
study ID and backed up on a separate encrypted University of Sheffield Google 
Drive and password protected, following standard protocols for handling imaging 
data.  
 
Anonymised MRI data will be electronically transferred to the study investigators 
Bioxydyn Ltd for independent analysis of the findings.  Consortium agreement is 
established between the two sites.  Anonymised data will also be made available 
for secondary research, educational or commercial purposes by third-party 
investigators from the private or public sector. 

 
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11.4 Publications and presentations 
All publications and presentations arising from this study are subject to the 
TRISTAN publication policy. In particular, this requires approval by the TRISTAN 
publication board prior to submission. Authorship is defined according to ICMJE 
criteria. 
11.5 Long-term data storage 
Upon completion of the study, imaging data will be fully anonymised and stored in 
the university-owned Google Drive.  Anonymous data may be made publicly 
available on zenodo.org in the future, also serving as a long-term repository. 
11.6 Withdrawal from the study 
 
In the event of a participant withdrawing from the study after one or more scans, 
unless explicitly requested by the participant any data collected prior to withdrawal 
will be retained for analysis to protect the integrity of the research data under the 
general data protection regulation exemption from the right of deletion in research. 
 
11.7 End of Study 
The end of this study is defined as the date on which the final MRI scan of the final 
participant is received. We expect this to be a short time after the date of their last visit.      
 
 
 

 
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12. References 
Andrade RJ, et al. “Drug-induced liver injury.” Nat Rev Dis Primers. 2019;5(1):58. 
doi: 10.1038/s41572-019-0105-0. PMID: 31439850. 
 
Di Leo E, et al. Cyclosporin-A efficacy in chronic idiopathic urticaria. Int J 
Immunopathol Pharmacol. 2011; 24(1): 195-200. doi: 
10.1177/039463201102400123. PMID: 21496403. 
 
Diabetes Prevention Program Research Group. “Long-term safety, tolerability, and 
weight loss associated with metformin in the Diabetes Prevention Program 
Outcomes Study.” Diabetes Care. 2012; 35(4): 731-7. doi: 10.2337/dc11-1299. 
PMID: 22442396; PMCID: PMC3308305. 
 
Du, J., et al. “Inhibition of the IGF signaling pathway reverses cisplatin resistance in 
ovarian cancer cells.” BMC Cancer., 2017, vol. 17, no. 1, 2017, p. 851, doi: 
10.1186/s12885-017-3840-1. 
 
Food and drug administration (FDA),”Physiologically Based Pharmacokinetic 
Analyses - Format and Content Guidance for Industry.” 2018. 
https://www.fda.gov/media/101469/download 
 
Food and drug administration (FDA), “GUIDANCE DOCUMENT i. In Vitro Drug 
Interaction Studies — Cytochrome P450 Enzyme- and Transporter-Mediated Drug 
Interactions Guidance for Industry.” 2020. https://www.fda.gov/regulatory-
information/search-fda-guidance-documents/in-vitro-drug-interaction-studies-
cytochrome-p450-enzyme-and-transporter-mediated-drug-interactions 
 
Food and drug administration (FDA), “GUIDANCE DOCUMENT ii. Clinical Drug 
Interaction Studies — Cytochrome P450 Enzyme- and Transporter-Mediated Drug 
Interactions Guidance for Industry” 2020. https://www.fda.gov/regulatory-
information/search-fda-guidance-documents/clinical-drug-interaction-studies-
cytochrome-p450-enzyme-and-transporter-mediated-drug-interactions 
 
Galetin A, Zhao P, Huang S-M. “Physiologically Based Pharmacokinetic Modeling of 
Drug Transporters to Facilitate Individualized Dose Prediction.” J Pharm Sci. 
2017;106(9):2204-2208. https://dx.doi.org/10.1016/j.xphs.2017.03.036 . PMID: 
28390843 
 
Georgiou L, et al. “Quantitative Assessment of Liver Function Using Gadoxetate-
Enhanced Magnetic Resonance Imaging: Monitoring Transporter-Mediated 
Processes in Healthy Volunteers.” Invest Radiol. 2017;52(2):111-119. 
https://dx.doi.org/10.1097/RLI.0000000000000316 . PMID: 28002117 

 
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Gertz, M., et al. “Cyclosporine inhibition of hepatic and intestinal CYP3A4, uptake 
and efflux transporters: application of PBPK modeling in the assessment of drug-
drug interaction potential.” Pharm Res., 2013, vol. 30, no. 3, pp. 761-80, doi: 
10.1007/s11095-012-0918-y. 
 
Guo Y, et al. “Advancing Predictions of Tissue and Intracellular Drug Concentrations 
Using In Vitro, Imaging and Physiologically Based Pharmacokinetic Modeling 
Approaches.” Clin Pharmacol Ther. 2018;104(5):865-889. 
https://dx.doi.org/10.1002/cpt.1183 . PMID: 30059145; PMCID: PMC6197917 
 
Hibma, J. E., et al. “The Effect of Famotidine, a MATE1-Selective Inhibitor, on the 
Pharmacokinetics and Pharmacodynamics of Metformin.” Clin Pharmacokinet, vol. 
55, 2016, pp. 711-21, https://doi.org/10.1007/s40262-015-0346-3. 
 
Izumi, S. et al. “Investigation of the Impact of Substrate Selection on In Vitro Organic 
Anion Transporting Polypeptide 1B1 Inhibition Profiles for the Prediction of Drug-
Drug Interactions” Drug metabolism and disposition, 2015, vol 43, no. 2, p. 235-147, 
DOI: https://doi.org/10.1124/dmd.114.059105. 
 
Jihadi, M. HA, et al. “Drug-related problems in hospitalized patients with type 2 
diabetes mellitus: A systematic review.” Explor Res Clin Soc Pharm, vol. 12, no. 12, 
2023, p. 100348, doi: 10.1016/j.rcsop.2023.100348. 
 
Kajosaari, L. I., et al. “Cyclosporine markedly raises the plasma concentrations of 
repaglinide.” Clinical Pharmacology & Therapeutics, 2005, vol. 78, pp. 388-99, 
https://doi.org/10.1016/j.clpt.2005.07.005. 
 
Kalliokoski, A., and M. Niemi. “Impact of OATP transporters on pharmacokinetics.” 
Br J Pharmacol, vol. 158, no. 3, 2009, pp. 693-705, doi: 10.1111/j.1476-
5381.2009.00430.x. 
 
Karageorgis, A., et al. “A multi-center preclinical study of gadoxetate DCE-MRI in 
rats as a biomarker of drug induced inhibition of liver transporter function.” PLoS 
One, 2018, vol. 13, no. 5,  p. e0197213, doi: 10.1371/journal.pone.0197213. 
 
Kenna JG, et al. “Can Bile Salt Export Pump Inhibition Testing in Drug Discovery and 
Development Reduce Liver Injury Risk? An International Transporter Consortium 
Perspective.” Clin Pharmacol Ther. 2018; 104(5): 916-932. doi: 10.1002/cpt.1222. 
PMID: 30137645; PMCID: PMC6220754. 
 
Kubitz R, et al. “The bile salt export pump (BSEP) in health and disease.” Clin Res 
Hepatol Gastroenterol. 2012; 36(6): 536-53. doi: 10.1016/j.clinre.2012.06.006. Epub 
2012 Jul 12. PMID: 22795478. 

 
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Kunze, A., et al. “Clinical Investigation of Coproporphyrins as Sensitive Biomarkers 
to Predict Mild to Strong OATP1B-Mediated Drug-Drug Interactions.” Clin 
Pharmacokinet., 2018, vol. 57, no. 12, pp. 1559-70, doi:10.1007/s40262-018-0648-3. 
 
Leonhardt, M., et al. “Hepatic uptake of the magnetic resonance imaging contrast 
agent Gd-EOB-DTPA: role of human organic anion transporters.” Drug Metab 
Dispos. 2010; 38(7): 1024-8. doi: 10.1124/dmd.110.032862. Epub 2010 Apr 20. 
PMID: 20406852 
 
Leyendecker, JR. “Gadoxetate Disodium for Contrast Magnetic Resonance Imaging 
of the Liver.” Gastroenterol Hepatol (N Y). 2009; 5(10): 698. PMID: 37967420; 
PMCID: PMC2886366 
 
Melillo, N., et al. “Use of In Vivo Imaging and Physiologically-Based Kinetic Modelling 
to Predict Hepatic Transporter Mediated Drug-Drug Interactions in Rats.” 
Pharmaceutics, 2023, vol. 15, no. 3, p. 896, doi: 10.3390/pharmaceutics15030896. 
 
Metry, M., et al. “Differential effects of metformin-mediated BSEP repression on 
pravastatin and bile acid pharmacokinetics in humans: A randomized controlled trial.” 
Clin Transl Sci., 2022, vol. 15, no. 10, pp. 2468-78, doi: 10.1111/cts.13375. 
 
Min T, et al. “Measurement of drug-induced inhibition of liver function with dynamic 
gadoxetate-enhanced MRI: a validation study in healthy volunteers.” ISMRM 
abstract. Singapore meeting, 2023. 
 
Murata, N., et al. “Gadolinium tissue deposition in brain and bone.” Magn Reson 
Imaging., 2016, vol. 34, no. 10, pp. 1359-65, doi:10.1016/j.mri.2016.08.025. 
 
Murata, N., et al. “Macrocyclic and Other Non-Group 1 Gadolinium Contrast Agents 
Deposit Low Levels of Gadolinium in Brain and Bone Tissue: Preliminary Results 
From 9 Patients With Normal Renal Function.” Invest Radiol., 2016, vol. 51, no. 7, 
pp. 447-53, doi:10.1097/RLI.0000000000000252. 
 
Osanlou R, et al. “Adverse drug reactions, multimorbidity and polypharmacy: a 
prospective analysis of 1 month of medical admissions” BMJ Open, 2021; 
12:e055551. doi: 10.1136/bmjopen-2021-055551 
 
Pirmohamed, M et al. “Adverse drug reactions as cause of admission to hospital: 
prospective analysis of 18820 patients.”  BMJ, 2004; 329: 15. 
 
Rodrigues, A. D. (Ed.). Drug-drug interactions. CRC Press. 2019. 
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Ruan, G., et al. “Metformin: update on mechanisms of action on liver diseases.” 
Front Nutr., 2023, vol. 14, no. 10, p. 1327814, doi: 10.3389/fnut.2023.1327814. 
 
Saito. S, et al. “Dynamic contrast-enhanced MRI of the liver in Mrp2-deficient rats 
using the hepatobiliary contrast agent Gd-EOB-DTPA.” Invest Radiol. 2013; 48(7): 
548-53. doi: 10.1097/RLI.0b013e3182856a06. PMID: 23442774 
 
Scotcher D, et al. “Physiologically Based Pharmacokinetic Modeling of Transporter-
Mediated Hepatic Disposition of Imaging Biomarker Gadoxetate in Rats.” Mol Pharm. 
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13. Appendix 
13.1 Serious adverse event reporting form 
 
REPORT OF SERIOUS ADVERSE EVENT (SAE) 
 
 
A Serious Adverse Event (AE) is a serious untoward medical occurrence or harm, resulting in death, 
life-threatening illness or injury, or other serious consequences, resulting from research activities. 
All SAEs should be recorded and reported to the Departmental/School Head of Department and 
Research Governance Lead not more than 24 hours after the study team becomes aware of the 
event. Following this, a review should be undertaken to assess the conduct and the ongoing 
suitability of the approved study protocol in light of the serious adverse event, including 
consideration of the need to report to the NHS REC (see below). The sponsor organisation at 
Sheffield Teaching Hospitals NHS Trust will be contacted at modhumita.harris@nhs.net.      
should also be notified within the 24 hour timeframe, and should be consulted on potential 
actions.  
 
 
1. Details of Principal Investigator 
Name: 
 
Email: 
 
Department/School: 
 
 
2. Details of study 
Full title of study: 
 
6 digit project code: 
 
Was the project reviewed by an NHS 
Research Ethics Committee*? 
*If so, an NHS SAE form must be submitted 
 
 
 
3. Type of event 
Please categorise this event, ticking all appropriate options: 

 
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Death 
Life threatening 
Hospitalisation or  
prolonging of existing  
hospitalisation  
Persistent or significant 
disability or incapacity 
Congenital anomaly  
or birth defect 
Other 
 
 
4. Circumstances of event 
Date of SAE: 
 
Location: 
 
Describe the circumstances of the 
event: 
 
(Attach copy of detailed report if 
necessary) 
 
What is your assessment of the 
implications, if any, for the safety 
of study participants and how will 
these be addressed? Consider 
both corrective and preventative 
actions. 
 
 
 
5. Declaration 
 
Name of Principal Investigator: 
Insert name here 
Signature: 
Date: Insert date here 
Name of Head of Department/School or Research Governance Lead: 
Insert name here 
Signature: 
Date: Insert date here 
 
6. Acknowledgement of receipt by the Director of Research, Partnerships & Innovation / 
Research Ethics & Integrity Manager: 
 
 
 
 
 
 

 
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Signed: 
 
Name: 
 
Position:  
 
Date: 
 
Signed original to be sent back to  Principal Investigator (or other person submitting report) 
Copy to be kept for information by Research, Partnerships & Innovation. 
 
13.2 REC reporting form 
Report of Serious Adverse Event (For all studies except Clinical Trials of Investigational 
Medicinal Products) 
The Chief Investigator (CI) should report any SAE that is both 
related to the research procedures and is unexpected. The report 
should be emailed to the Research Ethics Committee that gave a 
favourable opinion of the research within 15 days of the CI 
becoming aware of the event 
 
Details of the Chief Investigator 
Question 
Answer 
Name: 
Replace text here 
Address: 
 
Replace text here 
Telephone: 
Replace text here 
Email: 
Replace text here 
Details of the study 
Question 
Answer 
Full title of study: 
Replace text here 
Name of REC: 
Replace text here 

 
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REC reference number: 
Replace text here 
IRAS ID: 
Replace text here 
Research sponsor: 
Replace text here 
Sponsor’s reference for this 
report: 
(if applicable) 
Replace text here 
 
Type of event 
 
Please categorise this event, ticking all appropriate options: 
Death 
 
Life threatening 
 
Hospitalisation or prolongation of existing hospitalisation 
 
Persistent or significant disability or incapacity 
 
Congenital anomaly or birth defect 
 
Other 
 
 
Circumstances of event 
Question 
Answer 
Date of SAE: 
Replace text here 
Location: 
Replace text here 

 
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Describe the circumstances 
of the event: 
 
(Attach copy of detailed 
report if necessary) 
Replace text here 
What is your assessment of 
the implications, if any, for 
the safety of study 
participants and how will 
these be addressed? 
Replace text here 
 
Declaration 
Signature of Chief Investigator: 
Print name: 
Date of submission: 
 
Acknowledgement of receipt by REC (please insert name): 
The [                     ] Research Ethics Committee acknowledges receipt of the above. 
 
Signed: 
Name: 
Position on REC: 
Date: 
Signed original to be sent back to Chief Investigator (or other person submitting 
report) Copy to be kept for information by REC.