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L-thyroxine (L-T4)
L-thyroxine (L-T4) is a Thyroid hormone replacement Small molecule drug developed by Oregon Health and Science University. It is currently FDA-approved for Hypothyroidism (primary, secondary, tertiary), Thyroid cancer suppression therapy, Myxedema coma. Also known as: Subjects will remain on their usual brand of L-T4., Subjects on generic L-T4 will be switched to Levoxyl..
L-thyroxine is a synthetic thyroid hormone that replaces or supplements endogenous thyroid hormone to restore normal metabolic function.
L-thyroxine is a synthetic thyroid hormone that replaces or supplements endogenous thyroid hormone to restore normal metabolic function. Used for Hypothyroidism (primary, secondary, tertiary), Thyroid cancer suppression therapy, Myxedema coma.
At a glance
| Generic name | L-thyroxine (L-T4) |
|---|---|
| Also known as | Subjects will remain on their usual brand of L-T4., Subjects on generic L-T4 will be switched to Levoxyl. |
| Sponsor | Oregon Health and Science University |
| Drug class | Thyroid hormone replacement |
| Target | Thyroid hormone receptor (TR-alpha, TR-beta) |
| Modality | Small molecule |
| Therapeutic area | Endocrinology |
| Phase | FDA-approved |
Mechanism of action
L-thyroxine (T4) is converted peripherally to the more active T3 (triiodothyronine) and acts on thyroid hormone receptors in target tissues to regulate metabolism, growth, and development. It increases oxygen consumption and metabolic rate across multiple organ systems. The drug restores euthyroid state in patients with hypothyroidism or thyroid hormone deficiency.
Approved indications
- Hypothyroidism (primary, secondary, tertiary)
- Thyroid cancer suppression therapy
- Myxedema coma
- Thyroid hormone replacement after thyroidectomy or radioactive iodine therapy
Common side effects
- Tachycardia
- Palpitations
- Tremor
- Anxiety
- Insomnia
- Heat intolerance
- Weight loss
- Headache
Key clinical trials
- Novel Approaches to the Treatment of Hypothyroidism (PHASE2, PHASE3)
- Neuroendocrine Response in Pediatric Febrile Seizures
- T4/T3 Therapy in Hypothyroidism (PHASE2)
- Thyroid Hormone for Treatment of Nonalcoholic Steatohepatitis in Veterans (PHASE2)
- Dosing of LT4 in Older Individuals (PHASE4)
- A Study Evaluation the Safety and Efficacy of Hormone Replacement Therapy With North Star Compared to Levothyroxine in Patients With Primary Hypothyroidism (PHASE2)
- Thyroid Hormone Replacement After Radio Iodine: Value and Efficacy
- Levothyroxine Treatment on Cardiac Function in Children With Subclinical Hypothyroidism (NA)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- L-thyroxine (L-T4) CI brief — competitive landscape report
- L-thyroxine (L-T4) updates RSS · CI watch RSS
- Oregon Health and Science University portfolio CI
Frequently asked questions about L-thyroxine (L-T4)
What is L-thyroxine (L-T4)?
How does L-thyroxine (L-T4) work?
What is L-thyroxine (L-T4) used for?
Who makes L-thyroxine (L-T4)?
Is L-thyroxine (L-T4) also known as anything else?
What drug class is L-thyroxine (L-T4) in?
What development phase is L-thyroxine (L-T4) in?
What are the side effects of L-thyroxine (L-T4)?
What does L-thyroxine (L-T4) target?
Related
- Drug class: All Thyroid hormone replacement drugs
- Target: All drugs targeting Thyroid hormone receptor (TR-alpha, TR-beta)
- Manufacturer: Oregon Health and Science University — full pipeline
- Therapeutic area: All drugs in Endocrinology
- Indication: Drugs for Hypothyroidism (primary, secondary, tertiary)
- Indication: Drugs for Thyroid cancer suppression therapy
- Indication: Drugs for Myxedema coma
- Also known as: Subjects will remain on their usual brand of L-T4., Subjects on generic L-T4 will be switched to Levoxyl.
Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing