Cyclophosphamide in Treating Young Patients With Severe Autoimmune Enteropathy

OBJECTIVES:

Primary

- Determine the rate of treatment-free remission in young patients with severe autoimmune
enteropathy treated with high-dose cyclophosphamide.

Secondary

- Determine the toxic effects of this drug in these patients.

OUTLINE: Patients receive cyclophosphamide IV over 1 hour on days 1-4. Patients then receive
filgrastim (G-CSF) IV or subcutaneously once daily beginning on day 10 and continuing for 3
days or until blood counts recover.

After completion of study treatment, patients are followed periodically for up to 1½ years.

PROJECTED ACCRUAL: A total of 7-11 patients will be accrued for this study.

DISEASE CHARACTERISTICS:

- Diagnosis of severe autoimmune enteropathy

- Condition is resistant to conventional therapy

- Histologic evidence of severe villous atrophy with intense lymphocytic infiltrate of
the lamina propria by small intestinal biopsy within the past 3 months

- Disease failed to respond after ≥ 2 months of corticosteroid therapy at a dose of ≥
0.5 mg/kg/day or ≥ 40 mg/day for patients > 20 kg AND 1 of the following therapies:

- Cyclosporine resulting in ≥ 1 whole blood level of > 200 ng/mL

- Tacrolimus resulting in ≥ 1 whole blood level of 5 ng/mL

- At least 50% estimated caloric needs provided by parenteral nutrition

- History of intractable diarrhea, defined as frequent watery stools for > 3 months that
does not respond to dietary restriction

- No celiac disease, defined by a history of positive antiendomysial antibody or tissue
transglutaminase antibody

- No primary immunodeficiency or x-linked autoimmunity-allergy dysregulation

PATIENT CHARACTERISTICS:

Performance status

- Lansky 60-100%

Life expectancy

- Not specified

Hematopoietic

- Not specified

Hepatic

- Not specified

Renal

- Not specified

Cardiovascular

- Ejection fraction ≥ 40% OR shortening fraction ≥ 20%

Pulmonary

- FVC or FEV_1 ≥ 50% of predicted (for patients > 8 years of age)

- No clinically abnormal pulmonary function or abnormal pulse oximetry (for patients ≤ 8
years of age)

Other

- Not pregnant

- Negative pregnancy test

- Fertile patients must use effective contraception during and for at least 9 months
after completion of study treatment

- No known chromosomal abnormality

PRIOR CONCURRENT THERAPY:

Biologic therapy

- No immunizations for at least 6 months after completion of study treatment

Endocrine therapy

- See Disease Characteristics

- At least 5 days since prior corticosteroids

- No concurrent dexamethasone as an anti-emetic

Other

- At least 5 days since other prior immunosuppressive medications (e.g., tacrolimus or
cyclosporine)