A Study Evaluation the Safety and Efficacy of Hormone Replacement Therapy With North Star Compared to Levothyroxine in Patients With Primary Hypothyroidism

Recruitment Status
COMPLETED
(See Contacts and Locations)Verified January 2026 by Neuvosyn Laboratories, LLC
Sponsor
Neuvosyn Laboratories, LLC
Information Provided by (Responsible Party)
Neuvosyn Laboratories, LLC
Clinicaltrials.gov Identifier
NCT05712421
Other Study ID Numbers:
NorthStar-02-001
First Submitted
January 17, 2023
First Posted
February 2, 2023
Last Update Posted
February 17, 2026
Last Verified
January 2026

ClinicalTrials.gov processed this data on February 2026. Link to the current ClinicalTrials.gov record .

History of Changes

Study Details

Study Description

Condition or DiseaseIntervention/Treatment
Hypothyroidism
Drug: North StarDrug: Levothyroxine

Study Design

Study TypeInterventional
Actual Enrollment303 participants
Design AllocationRandomized
Interventional ModelParallel Assignment
MaskingQuadruple
Primary PurposeTreatment
Official TitleA Randomized, Double-blind, Dose-Conversion Study to Evaluate the Safety and Efficacy of Hormone Replacement Therapy With North Star Compared to Levothyroxine in Subjects With Primary Hypothyroidism Who Are Euthyroid on Levothyroxine Replacement Therapy
Study Start DateFebruary 27, 2023
Actual Primary Completion DateMay 4, 2025
Actual Study Completion DateSeptember 17, 2025

Groups and Cohorts

Group/CohortIntervention/Treatment
North Star
Drug: North Star
North Star
Levothyroxine
Drug: Levothyroxine
Levothyroxine

Outcome Measures

Primary Outcome Measures
  1. The ratio of the LT4 dose (mcg/day) at screening to North Star (mg/day) at the end of the treatment period required to achieve and maintain serum thyroid-stimulating hormone (TSH) levels within the normal reference range.
Secondary Outcome Measures
  1. Proportion of subjects who are euthyroid as determined by serum TSH level within the normal reference range at the end of the treatment period.

Eligibility Criteria

Ages Eligible for Study(Adult, Older Adult)
Sexes Eligible for StudyAll
Accepts Healthy VolunteersNo
Inclusion Criteria
Diagnosed with primary hypothyroidism
On continuous thyroid replacement therapy for at least 6 months before Study Entry
On a stable daily dose of LT4 for a minimum of 12 weeks prior to Screening
Agree to practice a method of contraception
Female patients not pregnant or lactating at Screening
Agree to practice a method of contraception of greater than 90% reliability
Willing to give written informed consent for the Study
Provide written authorization for use and disclosure of protected health information
Exclusion Criteria
Any clinical condition or previous surgery that might affect the absorption, distribution, biotransformation or excretion of North Star or levothyroxine
Hospitalization for a major illness within 4 weeks prior to Screening
Anticipated initiation or change in concomitant medications
Concomitant use of prohibited medications or supplements
Participated in another investigational new drug study within 30 days or 5 half-lives of the IMP, whichever is longer, prior to the first study drug administration.
For female subjects, be pregnant, nursing or planning to become pregnant during the study

Contacts and Locations

Sponsors and CollaboratorsNeuvosyn Laboratories, LLC
Locations
Neuvosyn Investigational Site | Birmingham Alabama, United States, 35209Neuvosyn Investigational Site | Canoga Park California, United States, 91304Neuvosyn Investigational Site | Greenbrae California, United States, 94904Neuvosyn Investigational Site | Toluca Lake California, United States, 91602Neuvosyn Investigational Site | Farmington Connecticut, United States, 06030Neuvosyn Investigational Site | Boca Raton Florida, United States, 33434Neuvosyn Investigational Site | Miami Florida, United States, 33144Neuvosyn Investigational Site | Miami Florida, United States, 33145Neuvosyn Investigational Site | Miami Florida, United States, 33155Neuvosyn Investigational Site | Miami Florida, United States, 33174Neuvosyn Investigational Site | Miami Florida, United States, 33179Neuvosyn Investigational Site | Sunrise Florida, United States, 33351Neuvosyn Investigational Site | Acworth Georgia, United States, 30101Neuvosyn Investigational Site | Atlanta Georgia, United States, 30318Neuvosyn Investigational Site | Columbus Georgia, United States, 31904Neuvosyn Investigational Site | Sugar Hill Georgia, United States, 30024Neuvosyn Investigational Site | Saginaw Michigan, United States, 48602Neuvosyn Investigational Site | Gladstone Missouri, United States, 64118Neuvosyn Investigational Site | Williamsville New York, United States, 14221Neuvosyn Investigational Site | Denver North Carolina, United States, 28037Neuvosyn Investigational Site | Winston-Salem North Carolina, United States, 27103Neuvosyn Investigational Site | Beavercreek Ohio, United States, 45440Neuvosyn Investigational Site | Columbus Ohio, United States, 31904Neuvosyn Investigational Site | Georgetown Texas, United States, 78628Neuvosyn Investigational Site | Houston Texas, United States, 77040Neuvosyn Investigational Site | Katy Texas, United States, 77450Neuvosyn Investigational Site | Katy Texas, United States, 77494Neuvosyn Investigational Site | Lewisville Texas, United States, 75067Neuvosyn Investigational Site | Paris Texas, United States, 75462Neuvosyn Investigational Site | Pearland Texas, United States, 77584Neuvosyn Investigational Site | Stafford Texas, United States, 77477