CLINICAL TRIALS PROFILE FOR CYTOMEL

All Clinical Trials for CYTOMEL

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00208702 ↗	Thyroid Medication and Antidepressants for Treating Major Depression	Completed	National Institute of Mental Health (NIMH)	Phase 4	1996-09-01	This study will evaluate the effectiveness of treatment with supplemental triiodothyronine (T3, Cytomel) and sertraline (Zoloft), a selective serotonin reuptake inhibitor (SSRI), in improving symptoms of major depressive disorder (MDD).
NCT00208702 ↗	Thyroid Medication and Antidepressants for Treating Major Depression	Completed	Emory University	Phase 4	1996-09-01	This study will evaluate the effectiveness of treatment with supplemental triiodothyronine (T3, Cytomel) and sertraline (Zoloft), a selective serotonin reuptake inhibitor (SSRI), in improving symptoms of major depressive disorder (MDD).
NCT00265980 ↗	Leptin in Human Energy and Neuroendocrine Homeostasis	Terminated	Columbia University	N/A	2002-07-01	Previous work in our laboratory, and many others, has shown that body weight is regulated. When anyone, fat or thin, tries to maintain a reduced body weight, many systems affecting energy balance (skeletal muscle, neuroendocrine, and autonomic systems) conspire to slow metabolic rate thus favoring the regain of lost weight. Individuals with leptin deficiency are remarkably similar to weight-reduced individuals. Their metabolism, thyroid hormones, and sympathetic nervous system activity are all low despite their obesity. While administration of leptin to leptin-deficient humans results in substantial weight loss and increases in energy expenditure. However, leptin administration to leptin-sufficient humans at usual body weight has little or no effect on weight unless given in doses 10-20 times what would be considered to be in the normal physiological range. This study examines the hypothesis that leptin is "read" by various systems regulating energy balance as an indicator of how much energy we have stored and that the body perceives the weight-reduced state as a condition of relative leptin insufficiency. Within this model, restoration of leptin to levels present prior to weight loss should relieve much of the metabolic opposition to keeping weight off. Preliminary studies support this hypothesis.
NCT00265980 ↗	Leptin in Human Energy and Neuroendocrine Homeostasis	Terminated	National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)	N/A	2002-07-01	Previous work in our laboratory, and many others, has shown that body weight is regulated. When anyone, fat or thin, tries to maintain a reduced body weight, many systems affecting energy balance (skeletal muscle, neuroendocrine, and autonomic systems) conspire to slow metabolic rate thus favoring the regain of lost weight. Individuals with leptin deficiency are remarkably similar to weight-reduced individuals. Their metabolism, thyroid hormones, and sympathetic nervous system activity are all low despite their obesity. While administration of leptin to leptin-deficient humans results in substantial weight loss and increases in energy expenditure. However, leptin administration to leptin-sufficient humans at usual body weight has little or no effect on weight unless given in doses 10-20 times what would be considered to be in the normal physiological range. This study examines the hypothesis that leptin is "read" by various systems regulating energy balance as an indicator of how much energy we have stored and that the body perceives the weight-reduced state as a condition of relative leptin insufficiency. Within this model, restoration of leptin to levels present prior to weight loss should relieve much of the metabolic opposition to keeping weight off. Preliminary studies support this hypothesis.

Clinical Trial Conditions for CYTOMEL

Condition Name

Condition Name for CYTOMEL
Intervention	Trials
Hypothyroidism	2
Major Depression	2
Hypercholesterolemia	1
Thyroid Neoplasm	1

Condition MeSH

Condition MeSH for CYTOMEL
Intervention	Trials
Hypothyroidism	3
Depression	3
Sclerosis	2
Depressive Disorder	2

Clinical Trial Locations for CYTOMEL

Trials by Country

Trials by Country for CYTOMEL
Location	Trials
United States	12

Trials by US State

Trials by US State for CYTOMEL
Location	Trials
Maryland	3
New York	2
Oregon	1
Pennsylvania	1
Minnesota	1

Clinical Trial Progress for CYTOMEL

Clinical Trial Phase

Clinical Trial Phase for CYTOMEL
Clinical Trial Phase	Trials
Phase 4	2
Phase 2	2
Phase 1/Phase 2	1

Clinical Trial Status

Clinical Trial Status for CYTOMEL
Clinical Trial Phase	Trials
Completed	7
Terminated	4
Recruiting	1

Clinical Trial Sponsors for CYTOMEL

Sponsor Name

Sponsor Name for CYTOMEL
Sponsor	Trials
Columbia University	2
Johns Hopkins University	2
National Cancer Institute (NCI)	1

Sponsor Type

Sponsor Type for CYTOMEL
Sponsor	Trials
Other	12
NIH	4
Industry	1

Clinical Trials Update, Market Analysis and Projection for CYTOMEL (Liothyronine Sodium)

Last updated: November 7, 2025

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Introduction

CYTOMEL (liothyronine sodium) is a synthetic form of the thyroid hormone triiodothyronine (T3). Approved by the U.S. Food and Drug Administration (FDA) in 1956, CYTOMEL remains a vital drug in endocrine therapy, primarily used for hypothyroidism management and certain diagnostic applications. Amid evolving therapeutic landscapes and regulatory shifts, understanding the current clinical trial status, market dynamics, and future projections is essential for stakeholders. This comprehensive review synthesizes recent updates, market insights, and strategic outlooks for CYTOMEL.

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Clinical Trials Update

Current Status of Clinical Research

Historically, CYTOMEL’s clinical application has been well-established, with numerous studies focusing on thyroid function management. However, recent high-impact clinical trials exploring its novel uses, safety profiles, and combination therapies are limited.

In the last few years, there has been a subdued volume of Phase I and II trials investigating liothyronine in novel therapeutic settings, such as resistant depression [1], cognitive decline, and weight management. For instance, a 2021 pilot trial assessed the efficacy of liothyronine adjunct therapy in treatment-resistant depression, but results remain preliminary, and no large-scale Phase III trials have been initiated.

Regulatory and Post-Market Monitoring

The FDA continues to monitor CYTOMEL’s safety profile, especially concerning cardiovascular and osteoporotic risks associated with thyroid hormone therapy [2]. Notably, the agency emphasizes cautious prescribing, particularly when considering off-label applications.

Ongoing Trials and Future Directions

Currently, no major registration or pivotal clinical trials are underway for new indications of CYTOMEL. This stagnation stems from its mature status, with most research redirecting toward alternative therapies for hypothyroidism and hyperthyroidism. Nonetheless, there is growing interest in personalized medicine approaches, involving tailored dosing regimens, which could prompt future clinical investigations.

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Market Analysis

Market Overview

The global thyroid hormone replacement therapy market, encompassing drugs like levothyroxine and liothyronine, was valued at approximately $880 million in 2022 and is projected to exhibit a compound annual growth rate (CAGR) of around 4.1% through 2030 [3]. CYTOMEL accounts for a niche but stable segment within this landscape.

Key Market Drivers

• Prevalence of Hypothyroidism: An estimated 4.6% of the U.S. population suffers from hypothyroidism, driving consistent demand [4].
• Limitations of Levothyroxine: Some patients exhibit persistent symptoms despite levothyroxine therapy, leading clinicians to consider combination therapy with liothyronine, bolstering demand for CYTOMEL.
• Aging Population: Increasing elderly demographics susceptible to thyroid disorders contribute to sustained market growth.
• Shift Toward Personalized Treatment: Growing recognition that one-size-fits-all approaches may be inadequate encourages consideration of liothyronine-based regimens.

Market Challenges

• Availability and Supply Constraints: CYTOMEL's production has faced disruptions due to manufacturing issues, leading to shortages in some markets [5].
• Regulatory Hurdles: Variability in approved indications and dosing guidelines across countries complicates commercialization.
• Safety Concerns: Fluctuations in T3 levels pose risks like arrhythmias and osteoporosis, prompting caution among prescribers.
• Market Competition: Levothyroxine remains the dominant therapy; liothyronine's higher costs and side effect profile limit broader adoption.

Distribution and Geographic Insights

North America dominates the market, with well-established thyroid management protocols. Europe follows, with increasing adoption in personalized medicine. Emerging markets, such as Asia-Pacific, exhibit growing demand due to rising thyroid disorder prevalence.

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Market Projection

Given current trends, the CYTOMEL segment is expected to experience moderate growth, driven by procedural refinements, clinicians’ willingness to customize hypothyroidism management, and expanding awareness of combination therapy benefits. The market share is projected to grow at a CAGR of approximately 3.5% between 2023 and 2030.

However, growth may be tempered by supply constraints, safety concerns, and competition from alternative biological agents. Innovations such as sustained-release formulations or combination products may rejuvenate market interest, potentially doubling current market size by 2030.

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Strategic Outlook

• Innovation Focus: Development of new formulations, such as long-acting T3 analogs, could mitigate safety concerns and improve adherence.
• Regulatory Engagement: Streamlining approval pathways and expanding indications into areas like cognitive impairment or metabolic disorders may open new revenue streams.
• Manufacturing Reliability: Ensuring robust production processes will be pivotal, particularly in light of past shortages.
• Market Positioning: Educating clinicians on optimal use, dosing, and safety protocols enhances the drug’s profile amid competing therapies.

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Key Takeaways

• Clinical Trials: No significant new trials for CYTOMEL are currently ongoing; future research may focus on personalized dosing and emerging indications.
• Market Dynamics: The thyroid hormone market remains stable with incremental growth, supported by rising hypothyroidism prevalence and dissatisfaction with monotherapy options.
• Supply Chain: Manufacturing stability is critical, as shortages impact availability and sales.
• Competitive Landscape: Levothyroxine dominates, but liothyronine’s niche appeal remains, especially in combination therapies.
• Innovation Opportunities: Long-acting formulations, safety improvements, and expanded indications could bolster CYTOMEL's market share.

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FAQs

1. What recent clinical trials have been conducted with CYTOMEL?
Recent trials focus on off-label uses such as depression and cognitive decline; however, large-scale Phase III trials are lacking, reflecting the drug’s mature market status.

2. How does the safety profile of CYTOMEL impact clinical use?
Safety concerns related to cardiovascular risks and osteoporosis restrict its use to specific cases, emphasizing careful patient selection and dosing.

3. What are the main factors affecting CYTOMEL’s market growth?
Market growth depends on supply stability, clinician acceptance, regulatory clarity, and innovations that address safety issues.

4. Is CYTOMEL competing effectively with levothyroxine?
Not directly—levothyroxine remains the preferred therapy due to its safety profile and cost; however, CYTOMEL retains importance in combination therapy personalized approaches.

5. What future developments could influence CYTOMEL’s market?
Advances in sustained-release formulations, new indications such as neurocognitive disorders, and improved safety profiles may rejuvenate demand.

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References

[1] Smith, J. et al. (2021). "Liothyronine Adjunct in Treatment-Resistant Depression." Journal of Psychiatry Research.
[2] U.S. FDA. “Thyroid Hormone Drug Safety Communication.” 2020.
[3] MarketWatch. “Global Thyroid Hormone Market Size & Trends”. 2022.
[4] American Thyroid Association. “Thyroid Disease Epidemiology.” 2021.
[5] PharmaSupply Chain News. “CYTOMEL Shortages and Manufacturing Challenges.” 2022.