A Phase 2/3 interventional study of Armour Thyroid and Levothyroxine in Hypothyroidism, sponsored by AbbVie. Active, not recruiting at 139 sites in 2 countries. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-10-13.
Sponsored by AbbVie · Phase 2/3, Interventional, and Treatment
This study will evaluate the efficacy and safety of Armour Thyroid treatment compared with synthetic T4 in subjects who have primary hypothyroidism and are currently stabilized (i.e., in-range thyroid-stimulating hormone [TSH]) on synthetic T4 treatment. This study will also therefore evaluate the efficacy and safety of dose conversion from synthetic T4 therapy to Armour Thyroid therapy.
217 studies on the registry are indexed under Hypothyroidism; 50 are open to participants now.
This study's enrollment of 2,701 is above the median of 70 across 109 interventional studies indexed under Hypothyroidism.
Browse Hypothyroidism studies →AbbVie is the lead sponsor of 973 studies on the registry; 133 are open to participants now.
Of its 357 completed or terminated interventional studies of FDA-regulated products, 214 (60%) have results posted.
Counted across the registry records on this site, refreshed daily.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive Armour Thyroid for up to 81 weeks.
Drug: Armour Thyroid
Participants will alternate between Armour Thyroid and synthetic T4 for up to 81 weeks.
Drug: Armour Thyroid · Drug: Levothyroxine
Oral Capsule or Tablet
Also known as: AGN-282176
Oral Capsule
Also known as: Synthetic T4
Percentage of Participants who Achieve Thyroid-Stimulating Hormone (TSH) Response
TSH response is defined as TSH values falling within 0.45 to 4.12 mIU/L (inclusive). TSH response will be determined at Week 55 and at a prior visit with no out-of-range TSH values in between (response rate is tested against a specified non-inferiority margin).
Time frame: Week 55
Number of Participants with Adverse Events (AEs)
An AE is defined as any untoward medical occurrence in a patient or clinical investigation in which a participant is administered a pharmaceutical product which does not necessarily have a causal relationship with this treatment.
Time frame: Up to approximately 90 weeks
Percentage of Participants who Achieve TSH Response
TSH response is defined as TSH values falling within 0.45 to 4.12 mIU/L. TSH response will be determined at Week 55 and at a prior visit with no out-of-range TSH values in between (response rate is tested against a specified non-inferiority margin \[stricter than the one used in the Primary Outcome Measure\]).
Time frame: Week 55
Number of Participants Needing Altered Dose Conversion from Synthetic T4 to Armour Thyroid
Number of participants needing altered dose conversion from synthetic T4 to Armour Thyroid.
Time frame: Up to approximately 29 weeks
Frequency of Dose Titrations During the Double-Blind (DB) Period Among Participants who Achieved TSH Response at the End of the DB Period
Frequency of dose titrations (0,1,2...) during the DB period among participants who achieved TSH response at the end of the DB period.
Time frame: Week 55
Showing the first 100 of 139 sites across 2 countries. Choose a country and city above to see the rest.
Plan to share: Yes — AbbVie is committed to responsible clinical trial data sharing. This includes access to anonymized, individual and trial-level data (analysis data sets), as well as other information.
Supporting information: Study protocol, Statistical analysis plan
Time frame: For details on when studies are available for sharing visit https://vivli.org/ourmember/abbvie/
Access criteria: To learn more about the process, or to submit a request, visit the following link https://www.abbvieclinicaltrials.com/hcp/data-sharing/
Data sharing details ↗ · vivli.org
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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