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

A 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

The North Star study is a multi-center, Phase 2, double-blind, randomized, parallel group clinical study to evaluate the safe and effective dose conversion from Levothyroxine to North Star therapy.

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