Levothyroxine Sodium in Thyroidectomized Patients Taking Proton Pump Inhibitors
Condition: Hypothyroidism;Postablative
MeSH terms: Hypothyroidism
Intervention: levothyroxine sodium capsule; Proton pump inhibitor (PPI); Levothyroxine Sodium (LT4) Tablets
Intervention description: after the run-in period, patients will be switched to levothyroxine sodium capsule at the same dose used during run-in; for the whole study duration all subjects will keep taking their proton pump inhibitor medication, as per prescription and as before inclusion; during the run-in period, subjects will continue taking their levothyroxine sodium tablet medication as per prescription and as before inclusion
Intervention MeSH terms: Esomeprazole; Omeprazole; Rabeprazole; Pantoprazole; Lansoprazole; Dexlansoprazole; Proton Pump Inhibitors
Phase: Phase 4
Study type: Interventional
Primary purpose: Treatment
Intervention model: Single Group Assignment
Masking: None (Open Label)
Enrollment: 66.0
Sex: All
Minimum age: 18 Years
Maximum age: 65 Years
Healthy volunteers: No

Summary:

      This is an open-label therapeutic efficacy study of Tirosint (levothyroxine sodium) capsules
      in thyroidectomized patients taking proton pump inhibitors and levothyroxine, evaluating
      changes in serum levels of Thyroid Stimulating Hormone (TSH) upon switch to Tirosint with
      respect to baseline.
    

Eligibility criteria:

        Inclusion Criteria:

          1. written informed consent duly read, signed and dated by the subject;

          2. aged ≥18 and ≤65 years;

          3. history of hypothyroidism due to total thyroidectomy;

          4. on stable LT4 doses for at least 6 weeks at screening (≥88 mcg daily and ≤250 mcg
             daily);

          5. TSH at screening ≥0.3 and ≤4.0 mIU/L;

          6. history of gastroesophageal reflux disease or associated gastrointestinal issues on
             prescription PPIs (i.e. omeprazole ≥20 mg daily, or esomeprazole ≥ 20 mg daily, or
             lansoprazole ≥ 15 mg daily, or pantoprazole ≥ 40 mg daily) for at least 8 weeks before
             screening visit and for whom chronic therapy with PPIs for the next 5 months has been
             prescribed;

          7. for women, adequate and continuative contraceptive measures until the end of the
             study, if not in menopause;

          8. reasonable assumption of understanding the study and willingness to take part to the
             study and to comply with protocol requirements.

        Exclusion Criteria:

          1. suspected or ascertained non-compliance with LT4 or PPI therapy;

          2. subject requiring changes of levothyroxine dose;

          3. use of over-the-counter (OTC) PPIs;

          4. history of malabsorption or history of gastric bypass surgery, short-gut syndrome,
             inflammatory bowel disease and other conditions of the gastrointestinal tract that may
             affect drug absorption (e.g. celiac disease)3;

          5. multiple co-morbidities (e.g. cardiac heart failure, active arrhythmia or history of
             arrhythmia, particularly atrial fibrillation, uncompensated diabetes mellitus,
             uncorrected adrenal insufficiency, seriously compromised hepatic, renal and/or
             respiratory functions);

          6. neoplastic pathology, active or in remission for less than 5 years (excluding the
             basic thyroid pathology);

          7. terminal condition;

          8. parenteral or assisted enteral feeding;

          9. presence of any medical condition or other circumstances which would significantly
             affect the safety of the subject or decrease the chance of obtaining reliable data,
             achieving study objectives or completing the study;

         10. history of alcoholism, drug abuse or psychiatric diseases that could invalidate the
             informed consent or limit the subject compliance with protocol requirements;

         11. pregnant (positive urine pregnancy test at screening or baseline visits) or
             breast-feeding subject or subject planning a pregnancy in the next months;

         12. known hypersensitivity to the ingredients of the preparation involved in the study3;

         13. use of forbidden concomitant medications;

         14. regular consumption of soy and soy derivatives, cotton seed meals, walnuts, and
             dietary fibres;

         15. participation in other clinical studies during the 3 months prior to screening;

         16. presumption of poor reliability/cooperation;

         17. any reason which, in the opinion of the Investigator, would prevent the subject from
             participating in the study.