An Open Label Phase 2 Extension Study of Higher Dose Sialic Acid-Extended Release (SA-ER) Tablets and Sialic Acid-Immediate Release (SA-IR) Capsules in Patients With Glucosamine (UDP-N-acetyl)-2-Epimerase (GNE) Myopathy
Condition: GNE Myopathy; Hereditary Inclusion Body Myopathy (HIBM)
MeSH terms: Muscular Diseases; Distal Myopathies
Intervention: SA-ER 500 mg; SA-IR 500 mg
Intervention description: oral tablets; oral capsules
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Non-Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Enrollment: 59.0
Sex: All
Minimum age: 18 Years
Maximum age: 65 Years
Healthy volunteers: No

Summary:

      The safety objectives of the study are to: evaluate additional long-term safety of SA-ER
      treatment of participants with GNE myopathy previously treated with SA-ER at dose of 6g/day
      (Part I); evaluate the safety of 12g /day SA (delivered by 1.5g of SA-ER tablets and 1.5g of
      SA-IR capsules 4 times per day) in the treatment of participants with GNE myopathy (Part II)
      over a 6 month treatment period; evaluate the safety of SA treatment at both 6g/day and 12
      g/day (Part III [SA-ER/SA-IR] and Part IV [SA-ER]).
    

Eligibility criteria:

        Inclusion Criteria:

          -  Enrollment in, and successful completion of the UX001-CL201 (NCT01517880) protocol OR
             (for 10 treatment naïve subjects):

               -  Have a confirmed diagnosis of GNE Myopathy

               -  Aged 18 -65 years of age, inclusive

               -  Able to walk ≥ 200 meters and < 80% of predicted normal during the 6-Minute Walk
                  Test (6MWT; orthotics and assistive devices allowed)

          -  Must be willing and able to provide written, signed informed consent after the nature
             of the study has been explained, and prior to any research-related procedures

          -  Must be willing and able to comply with all study procedures

          -  Sexually active subjects must be willing to use an acceptable method of contraception
             while participating in the study

          -  Females of childbearing potential must have a negative pregnancy test at Baseline and
             be willing to have additional pregnancy tests during the study. Females considered not
             of childbearing potential include those who have been in menopause for at least two
             years, or have had tubal ligation at least one year prior to Baseline, or who have had
             total hysterectomy

        Exclusion Criteria:

          -  Use of any investigational product (other than SA-ER tablets) to treat GNE myopathy

          -  Ingestion of N-acetyl-D-mannosamine (ManNAc) or similar SA-producing compounds

          -  Pregnant or breastfeeding at Baseline or planning to become pregnant (self or partner)
             at any time during the study

          -  Has had any hypersensitivity to SA or its excipients that, in the judgment of the
             investigator, places the subject at increased risk for adverse effects

          -  Have any co-morbid conditions, including unstable major organ-system disease(s) that
             in the opinion of the investigator, places the subject at increased risk of
             complications, interferes with study participation or compliance, or confounds study
             objectives.