An Extension Study Assessing the Safety and Efficacy of AVTX-803 in Subjects with Leukocyte Adhesion Deficiency Type II

Sialyl-Lewis X antigen expression on leukocytes

Time frame: At 6 months

Change from Baseline in the composite Nijmegen Pediatric Congenital Disorders of Glycosylation (CDG) Rating Scale (NPCRS)

The NPCRS comprises 3 sections, with each section containing specific items relevant to the assessment of subjects with CDG. Section I (Current Function); Section II (System Specific Involvement); and Section III (Current Clinical Assessment). The sum of the scores is used to scale patients into 3 domains: mild (0-14), moderate (15-25), and severe (\>26) category.

Time frame: Through study completion, an average of 1 year.

Change from Baseline in the individual parameters of the Nijmegen Pediatric Congenital Disorders of Glycosylation (CDG) Rating Scale (NPCRS)

The NPCRS comprises 3 sections, with each section containing specific items relevant to the assessment of subjects with CDG. Section I (Current Function); Section II (System Specific Involvement); and Section III (Current Clinical Assessment). The sum of the scores is used to scale patients into 3 domains: mild (0-14), moderate (15-25), and severe (\>26) category.

Time frame: Through study completion, an average of 1 year.

Goal Attainment Score (GAS)

The parent (or subject) formulates 3 individual goals for improving quality of life. Typically, these goals affect mobility, independence, and disease-related health aspects. These goals will be re-evaluated and scored by the parent or subject at each study visit within a scale of -2 to +2.

Time frame: Through study completion, an average of 1 year.