Selenium Supplementation Versus Placebo in Patients With Graves' Hyperthyroidism
GRAves Selenium Supplementation Trial (GRASS) - an Investigator-initiated Randomised, Blinded, Multicentre Clinical Trial of Selenium Supplementation Versus Placebo in Patients With Graves' Hyperthyroidism
  • Phase

  • Study Type

  • Status

    Active, not recruiting
  • Study Participants

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.
Study Started
Oct 31
Primary Completion
Aug 31
Study Completion
Aug 31
Last Update
Dec 23

Dietary Supplement Selenium

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.

  • Other names: 'Selen, organisk selen', produced by Jemo-Pharm A/S

Other Placebo

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.

Selenium Active Comparator

Placebo Placebo Comparator


Inclusion Criteria:

Age 18 years or older.
Active Graves' hyperthyroidism (suppressed TSH (< 0.1) and positive TRAb) measured within the last two months prior to the inclusion date.
Written informed consent

Exclusion Criteria:

Major co-morbidity, making the participants unlikely to continuously receive trial intervention in the intervention period.
Previous treatment with radioactive iodine.
Current ATD treatment having been received for more than two months.
Treatment with immunomodulatory drugs, such as cyclosporine A, methotrexate, cyclophosphamide.
Allergy towards the components in the selenium and placebo pills.
Pregnant or breast-feeding women.
Intake of selenium supplementation above 70 µg per day (70 µg corresponds to the amount in a multivitamin tablet).
Unable to read and understand Danish.
Lack of informed consent
No Results Posted