An interventional study of Selenium and Placebo in Graves' Hyperthyroidism, sponsored by Rigshospitalet, Denmark. Completed at 8 sites in Denmark. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-02-13.
Sponsored by Rigshospitalet, Denmark · Not applicable, Interventional, and Treatment
The purpose of this study is to investigate if selenium supplementation to the standard treatment with anti-thyroid drugs in patients with Graves' hyperthyroidism, will lead to a fewer people with anti-thyroid treatment failure and faster remission, in terms of better quality of life during the first year of treatment and more patients staying in remission.
Exclusion Criteria:
Dietary Supplement: Selenium
Other: Placebo
100 µg tablets. The dose of daily supplement of selenium is set at 200 µg (two tablets). The duration of the intervention period is between 24-30 months. This is defined by the time of ATD treatment withdrawal, which is scheduled between approximately 12-18 months after randomisation. Selenium supplementation will continue 12 months after withdrawal of ATD treatment.
Also known as: 'Selen, organisk selen', produced by Jemo-Pharm A/S
Placebo tablets, identical in regards to size, appearance, taste, smell, and solubility to the experimental intervention tablet will be produced by Jemo-Pharm A/S, http://www.jemo-pharm.dk/frame.cfm/cms/id=977/sprog=2/grp=6/menu=1/ (content as in section: Auxiliary agents). The placebo regimen will be identical to the selenium regimen, but consist of two non-active tablets per day for 24-30 months.
Proportion of participants with the composite outcome of 'ATD treatment failure'
'ATD treatment failure' is defined as: * The participant receives ATD treatment (at any level) during the last 12 months (± 1 month) of the intervention period; or * The participant has thyroid hyperfunction (TSH \<0.1) during the last 12 months (± 1 month) of the intervention period; or * The participant has been referred to ablative therapy (radioactive iodine or thyroid surgery) at some point during the entire intervention period.
Time frame: Last 12 months (± 1 month) of the intervention period
Proportion of participants who receives ATD treatment (at any level) during the last 12 months (± 1 month) of the intervention period
Time frame: Last 12 months (± 1 month) of the intervention period
Proportion of participants who has thyroid hyperfunction (TSH <0.1) during the last 12 months (± 1 month) of the intervention period
Time frame: Last 12 months (± 1 month) of the intervention period
Proportion of participants who has been referred to ablative therapy (radioactive iodine or thyroid surgery) at some point during the entire intervention period
Time frame: Intervention period (24-30 months)
Thyroid-specific QoL during the first year after randomisation, and at the end of the intervention period (24-30 months), as measured by the global score in the ThyPRO questionnaire
Time frame: First year after randomisation, and at the end of the intervention period (24-30 months)
Level of TRAb at 18 months, and at the end of the intervention period (24-30 months)
Time frame: 18 months, and at the end of the intervention period (24-30 months)
Hyperthyroid symptoms (ThyPRO subscale) during first year after randomisation
Time frame: First year after randomisation
Eye symptoms (ThyPRO subscale) during first year after randomisation, and at end of the intervention period (24-30 months)
Time frame: First year after randomisation, and at end of the intervention period (24-30 months)
Number of participants with adverse reactions during the intervention period
Participants will be asked to report about known adverse reactions (specified in the protocol) at 6 weeks, 12 weeks, 6 months, 12 months, 18 months, 24 months, and 12 months after ATD treatment withdrawal. In addition, participants are instructed to contact their trial contact person in case they experience adverse reactions.
Time frame: Intervention period (24-30 months)
Number of participants with serious adverse events during the intervention period
To make sure we get information on serious adverse events, data on hospital admissions and mortality will be obtained through the national databases (the National Patient Registry and the Danish Civil Registration System) at the end of the trial. Also, participants are informed and instructed to contact their trial contact person in case they: * are admitted to a hospital for selenium intoxication; * experience a clinical picture indicative of selenium intoxication; or * experience a clinical picture unexpected, but suspected to be related to selenium intoxication.
Time frame: Intervention period (24-30 months)
This study is completed, as verified in Feb 2025. You cannot join it, but the record below documents what was studied.
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Rigshospitalet, Denmark