A research study testing whether a single dose of [18F]AldoView can produce useful images of adrenal glands allowing identification of participants with and without primary aldosteronism

Approved 13/04/2026, London - Brighton & Sussex Research Ethics Committee (2 Redman Place, Stratford, London, E20 1JQ, United Kingdom; -; brightonandsussex.rec@hra.nhs.uk), ref: 26/LO/0207

Correct Localisation Rate (CLR), defined as the proportion of participants with correct localisation of the affected adrenal gland, determined by concordance between [18F]AldoView PET-CT findings and post-surgical CYP11B2 immunohistochemical (IHC) staining. [18F]AldoView PET-CT is performed on Day 1 and interpreted by blinded readers, and results are compared with CYP11B2 IHC staining of resected adrenal tissue obtained at adrenalectomy (reference standard). CLR is assessed once both PET-CT and IHC results are available for each participant, with final analysis conducted at study completion in participants with evaluable PET-CT and conclusive IHC results.

1. The safety and tolerability of a single intravenous dose of [18F]AldoView, assessed by the incidence of treatment-emergent adverse events (TEAEs). The variable measured is the occurrence of one or more TEAEs. TEAEs are recorded from the time of intravenous administration of [18F]AldoView until completion of the scheduled safety follow-up call conducted between Day 4 and Day 8 post-dose.
2. The diagnostic accuracy of [18F]AldoView PET-CT for detecting primary aldosteronism (PA). The variables measured are positive percent agreement and negative percent agreement of [18F]AldoView PET-CT relative to the reference diagnosis of PA (PA-positive or PA-negative). PET-CT imaging is performed on Day 1 and interpreted by blinded readers, and results are compared with the reference diagnosis. Diagnostic accuracy is assessed once both PET-CT and reference diagnostic results are available for each participant, with final analysis conducted at study completion.

Exploratory outcomes:
1. The ability of [18F]AldoView PET-CT to predict the outcome of adrenalectomy in participants with PA. The variables measured are the sensitivity and specificity of PET-CT for predicting biochemical and clinical cure. PET-CT scans performed on Day 1 are interpreted by the trial multidisciplinary team (MDT), and findings are compared with post-operative outcomes classified according to the Primary Aldosteronism Surgical Outcome (PASO) criteria. Postoperative biochemical and clinical outcomes are assessed according to PASO at the scheduled post-surgical follow-up visits (6 and 12 months), and predictive accuracy is determined once both PET-CT interpretations and PASO-defined outcomes are available for each participant, with final analysis conducted at study completion.
2. The biodistribution and radiation dosimetry of [18F]AldoView. The variable measured is the effective radiation dose (mSv per MBq administered). Dosimetry is derived from whole-body PET-CT scans performed in four participants from the IDEAL1 First-in-Human study and four additional participants enrolled in the IDEAL2 dosimetry sub-study. The effective dose is calculated based on the distribution of radioactivity in organs and tissues over time, with correction for urinary excretion. Dosimetry analysis is conducted after completion of the required whole-body imaging and associated radioactivity measurements for each participant.
3. The impact of [18F]AldoView PET-CT on patient management. The variable measured is the proportion of participants with a change in initial treatment intent based on standard of care (SoC). Initial treatment intent is documented prior to [18F]AldoView PET-CT, and any change in management plan is recorded after PET-CT results are reviewed and shared with the treating clinical team. The outcome is assessed by comparing pre-scan and post-scan treatment intent for each participant, with final analysis conducted at study completion.
4. The inter-reader performance and agreement for [18F]AldoView PET-CT interpretation. The variables measured are: (1) the diagnostic performance of each blinded reader compared with the reference standard (standard of truth) and (2) the level of agreement and discordance between blinded readers. PET-CT scans performed on Day 1 are independently interpreted by blinded readers, and their assessments are compared with the reference standard once available. Inter-reader agreement and individual reader performance are analysed after both PET-CT interpretations and reference standard results are available for each participant, with final analysis conducted at study completion.
5. The correlation between [18F]AldoView PET-CT findings, adrenal somatic mutations, demographics, and surgical outcomes. The variables measured include: (1) the presence and characteristics of lesions detected by [18F]AldoView PET-CT, (2) somatic mutations identified in surgically resected adrenal tissue, (3) participant demographic characteristics, and (4) post-surgical outcomes. Somatic mutation analysis is performed on resected adrenal tissue in participants who undergo adrenalectomy and have genetic testing available. Associations between PET-CT findings and mutation status, as well as correlations between demographics, mutation status, and surgical outcomes, are analysed once imaging, histological/genetic, and outcome data are available, with final analysis conducted at study completion.
6. The cost and cost-effectiveness of [18F]AldoView PET-CT compared with the current SoC diagnostic pathway. The variables measured include healthcare resource utilisation and associated costs of the diagnostic pathway, as well as long-term cost-effectiveness outcomes. Resource use and cost data are collected throughout the trial, and an economic evaluation comparing [18F]AldoView PET-CT with current SoC is conducted at the conclusion of the study, once all relevant clinical and imaging data have been collected.
7. The correlation between quantitative [18F]AldoView PET parameters and SoC diagnostic and surgical outcomes in PA. The variables measured include quantitative PET metrics (e.g., adrenal tracer uptake and adrenal standardised uptake value [SUV]), biochemical diagnosis of PA, adrenal vein sampling (AVS) lateralisation results, cortisol co-secretion status, and surgical outcomes. PET-CT scans are performed on Day 1 and reported by the trial multidisciplinary team (MDT) upon completion. Biochemical diagnosis of PA is recorded at enrolment; AVS lateralisation and cortisol co-secretion are recorded upon completion of SoC diagnostic testing; and surgical outcomes are assessed 6–12 months after adrenalectomy when biochemical and clinical follow-up data become available. Correlations between quantitative PET parameters and these outcomes are analysed once relevant paired data are available, and optimal threshold values for PET metrics are derived using receiver operating characteristic (ROC) curve analysis or other appropriate methods to maximise diagnostic accuracy.
8. The feasibility of determining the Correct Localisation Rate (CLR) at the lesion level. The variables measured are: (1) the proportion of PET-positive adrenal lesions for which lesion-level CLR can be determined through trial team assessment of lesion location and correlation with CYP11B2-positive features on pathology (i.e., adequate lesion matching is feasible), and (2) a descriptive estimate of lesion-level CLR within this subset. Lesion location on [18F]AldoView PET-CT is compared with CYP11B2 immunohistochemical (IHC) findings from resected adrenal tissue in surgically treated participants with primary aldosteronism. Analysis is performed once both PET imaging data and corresponding lesion-level CYP11B2 IHC results are available for all participants undergoing adrenalectomy.