A Single-Dose Open-Label Study of XOMA 358 in Subjects With Congenital Hyperinsulinism

Inclusion Criteria:

- Clinical diagnosis of congenital hyperinsulinism

- Documented hypoglycemia (blood glucose < 60mg/dL) during two monitored fasts or two
protein challenges before drug administration.

- Can safely washout of background medications used to treat hyperinsulinism.

Exclusion Criteria:

- Use of any agent, such as diazoxide, octreotide, chronic systemic glucocorticoids, or
β agonists that may affect glucose metabolism

- Use of any long-acting somatostatin analogs or glucose-affecting medications that
require > 72 hour washout

- Body Mass Index ≥ 35 kg/m2

- Pregnant females, females planning to become pregnant during the course of the study,
females who have delivered 3 months before screening, or breastfeeding

- Male subjects who are planning a pregnancy with a female partner during the course of
the study or within 4 months after administration of study drug.