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Study of XP-8121 For the Treatment of Adult Subjects With Hypothyroidism

Phase 2
Completed
Conditions
Hypothyroidism
Interventions
Registration Number
NCT05823012
Lead Sponsor
Xeris Pharmaceuticals
Brief Summary

This is a non-randomized, open-label, single arm, self-controlled study of XP-8121 (levothyroxine sodium) to determine a target dose conversion factor from stably dosed oral levothyroxine to XP-8121 (levothyroxine sodium) in patients with hypothyroidism and to assess the safety and tolerability of XP-8121(levothyroxine sodium) after once weekly subcutaneous injections. This study includes the following periods: Screening, Titration Period, and Maintenance Period. The study will conclude with an End of Maintenance Visit or Early Termination (ET) Visit.

Detailed Description

This is a non-randomized, open-label, single arm, self-controlled study of XP-8121 (levothyroxine sodium) to determine a target dose conversion factor from stably dosed oral levothyroxine to XP-8121 (levothyroxine sodium) in patients with hypothyroidism and to assess the safety and tolerability of XP-8121 (levothyroxine sodium) after once weekly subcutaneous injections. This study includes the following periods: Screening, Titration Period (2 to 8 weeks), and Maintenance Period (4 weeks). A pharmacokinetic substudy will be conducted for a subset of patients during the Maintenance Period. The study will conclude with an End of Maintenance Visit or Early Termination (ET) Visit.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
46
Inclusion Criteria
  • Provide written informed consent.
  • Male or female between the ages of 18 and 65 years (inclusive) at Screening, with chronic hypothyroidism and on a stable dose of oral levothyroxine (Synthroid or an FDA-approved generic equivalent to Synthroid) or, if in the pharmacokinetic substudy, Synthroid only for at least 3 months.
  • TSH within the normal range at Screening (central laboratory) and at least 3 months prior to Screening (documented by local laboratory).
  • Free thyroxine within the normal range at Screening (central laboratory).
Exclusion Criteria
  • History of hypersensitivity to levothyroxine (any formulation).
  • Current dose of oral levothyroxine, based on body weight >2 μg/kg/day.
  • Current levothyroxine total daily dose either <50 μg or >375 μg.
  • Current use of combined thyroid treatment (i.e., Synthroid plus liothyronine or Synthroid plus Armour Thyroid) and/or any other levothyroxine aside from those used in the study.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
XP-8121levothyroxine sodiumXP-8121 100 to 1500 μg subcutaneous injection
Primary Outcome Measures
NameTimeMethod
Dose conversion factorDay 29 of the Maintenance Period

Geometric mean ratio of the weekly dose of XP-8121 to the daily dose of oral levothyroxine (aka dose conversion factor), where the XP-8121 dose corresponds to the administration immediately preceding collection of blood TSH used to determine normalization at the end of Maintenance Period

Secondary Outcome Measures
NameTimeMethod
Proportion of subjects enrolled with normalized TSHDay 29 of the Maintenance Period

Proportion of subjects enrolled with normalized TSH at the end of Maintenance Period

Thyroid hormone concentrationsDay 8

Blood thyroid hormone concentrations (total thyroxine, free thyroxine and TSH) following the first dose of XP-8121 in the Titration Period

Trial Locations

Locations (6)

Panax Clinical Research, LLC

🇺🇸

Miami Lakes, Florida, United States

American Research Corporation

🇺🇸

San Antonio, Texas, United States

Rainier Clinical Research Center

🇺🇸

Renton, Washington, United States

ProSciento, Inc.

🇺🇸

Chula Vista, California, United States

Catalina Research Institute, L.L.C.

🇺🇸

Montclair, California, United States

Mt. Olympus Medical Research, LLC

🇺🇸

Sugar Land, Texas, United States

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