A Phase I Study Of Etrolizumab Followed By Open-Label Extension And Safety Monitoring In Pediatric Patients With Moderate To Severe Ulcerative Colitis Or Moderate To Severe Crohn's Disease

Inclusion Criteria:

- Age of 4 years to <18 years at the time of signing the Informed Consent Form.

- Weight of 13 kg or more

- Diagnosis of ulcerative colitis (UC) or Crohn's Disease (CD) confirmed by biopsy and
established for >=3 months (i.e., after first diagnosis by a physician according to
American College of Gastroenterology [ACG] guidelines) prior to screening

- Inadequate response, loss of response or intolerance to prior immunosuppressants
and/or corticosteroid treatment and/or anti-tumor necrosis factor (TNF) therapy

- For postpubertal females of childbearing potential: agreement to remain abstinent
(refrain from heterosexual intercourse) or use acceptable contraceptive methods during
the treatment period and for at least 24 weeks after the last dose of etrolizumab.

- For male patients: agreement to remain abstinent (refrain from heterosexual
intercourse) or use contraceptive measures, and agreement to refrain from donating
sperm

Exclusion Criteria:

- Pregnant or lactating

- Lack of peripheral venous access

- Congenital or acquired immune deficiency

- Neurological conditions or diseases that may interfere with monitoring for progressive
multifocal leukoencephalopathy (PML)

- History of demyelinating disease

- History of cancer, including hematologic malignancy, solid tumors, and carcinoma in
situ, within 5 years before screening

Exclusion Criteria Related to Inflammatory Bowel Disease:

- Prior extensive colonic resection, subtotal or total colectomy, or planned surgery

- Past or present ileostomy or colostomy

- Diagnosis of indeterminate colitis

- Suspicion of ischemic colitis, radiation colitis, or microscopic colitis

- Diagnosis of toxic megacolon within 12 months of initial screening visit

- Abdominal abscess

- A history or current evidence of colonic mucosal dysplasia

- Patients with fixed symptomatic stenosis of the intestine

- Patients with history or evidence of adenomatous colonic polyps that have not been
removed

Exclusion Criteria Related to Ulcerative Colitis

- Severe extensive colitis per investigator judgment that colectomy is imminent

Exclusion Criteria Related to Crohn's Disease

- Sinus tract with evidence for infection (e.g., purulent discharge) in the clinical
judgment of the investigator

- Short-bowel syndrome

- Evidence of abdominal or perianal abscess

- Expected to require surgery to manage CD-related complications during the study

Exclusion Criteria Related to Prior or Concomitant Therapy

- Any prior treatment with anti-integrin agents (including natalizumab, vedolizumab, and
efalizumab), ustekinumab, anti-adhesion molecules (e.g., anti-MAdCAM-1), or rituximab

- Use of IV steroids within 30 days prior to screening with the exception of a single
administration of IV steroid

- Use of agents that deplete B or T cells (e.g., alemtuzumab or visilizumab) within 12
months prior to Day 1, with the exception of AZA and 6-MP

- Use of cyclosporine, tacrolimus, sirolimus, or mycophenolate mofetil (MMF) within 4
weeks prior to Day 1

- Use of other biologics (e.g. anti-TNF) within 8 weeks before dosing (unless drug level
is below detectability before completion of the 8-week interval)

- Chronic nonsteroidal anti-inflammatory drug (NSAID) use

- Patients who are currently using anticoagulants

- Apheresis (i.e., Adacolumn apheresis) within 2 weeks prior to Day 1

- Received any investigational treatment including investigational vaccines within 12
weeks prior to Day 1 of the study or 5 half-lives of the investigational product,
whichever is greater

- History of moderate or severe allergic or anaphylactic/anaphylactoid reactions to
chimeric, human, or humanized antibodies, fusion proteins, or murine proteins or
hypersensitivity to etrolizumab (active drug substance) or any of the excipients
(L-histidine, L-arginine, succinic acid, polysorbate 20)