Hematopoietic Stem Cell Support in Patients With Refractory Sarcoidosis

Method of Harvesting Stem Cells

Based on the experience of the pilot studies, the current protocol will mobilize stem cells
with granulocyte-colony stimulating factor (G-CSF) and collect stem cells by apheresis, with
subsequent bone marrow harvest performed only if needed to supplement the peripheral blood
stem cells (PBSC). Based on experience of autoimmune flares in patients receiving G-CSF alone
for mobilization, patients will be mobilized with cyclophosphamide 2.0 g/m2 and G-CSF 10
mcg/kg.

Cyclophosphamide

Cyclophosphamide (CY) is an active agent in patients with a wide variety of malignancies. It
is used frequently in the therapy of lymphoid malignancies and has potent immunosuppressive
activity. It is frequently used as a cytotoxic and immunosuppressive agent in patients
undergoing marrow transplants and as a treatment for patients with autoimmune diseases. It is
an alkylating agent that requires hepatic metabolism to the active metabolites, phosphoramide
mustard and acrolein. These active metabolites react with nucleophilic groups. It is
available as an oral or intravenous preparation. Bioavailability is 90% when given orally.
The half-life of the parent compound is 5.3 hours in adults, and the half-life of the major
metabolite phosphoramide mustard is 8.5 hours. Liver or renal dysfunction will lead to
prolonged serum half-life. CY is administered intravenously at a dosage of 60 mg/kg on each
of 2 successive days (use adjusted ideal body weight if patient's actual body weight is
greater than 100% ideal body weight). The major dose limiting side effect at high doses is
cardiac necrosis. Hemorrhagic cystitis can occur and is mediated by the acrolein metabolite.
This can be prevented by co-administration of MESNA or bladder irrigation. Other notable side
effects include nausea, vomiting, alopecia, myelosuppression and SIADH. Refer to
institutional manuals for more information about administration, toxicity and complications.

Rabbit-Derived Anti-Thymocyte Globulin (ATG)

Rabbit-derived anti-human thymocyte globulin (ATG) is a gamma globulin preparation obtained
from hyperimmune serum of rabbits immunized with human thymocytes. ATG has been used
predominately in solid organ transplant immunosuppressive regimens. ATG is a predominantly
lymphocyte-specific immunosuppressive agent. It contains antibodies specific to the antigens
commonly found on the surface of T cells. After binding to these surface molecules, ATG
promotes the depletion of T cells from the circulation through mechanisms, which include
opsonization and complement-assisted, antibody-dependent, cell-mediated cytotoxicity. The
plasma half-life ranges from 1.5 12 days. ATG is administered intravenously at a dose of
0.5-mg/kg recipient body weight on day -6 and at a dose of 1.0 mg/kg recipient body weight on
days -5 to -1. Unlike equine ATG, rabbit ATG does not require a pre-infusion skin test to
check for hypersensitivity. Methylprednisolone 250mg (dose adjusted based on patient's
condition) will be given before every dose of ATG. Additional medications such as
diphenhydramine may be given at the discretion of the attending physician. Although rare, the
major toxicity is anaphylaxis; chills, fever, pruritus or serum sickness may occur.

Fludarabine

Fludarabine phosphate is rapidly dephosphorylated to 2-fluoro-ara-A and then phosphorylated
intracellularly by deoxycytidine kinase to the active triphosphate, 2-fluoro-ara-ATP. This
metabolite appears to act by inhibiting DNA polymerase alpha, ribonucleotide reductase and
DNA primase, thus inhibiting DNA synthesis. The mechanism of action of this antimetabolite is
not completely characterized and may be multi-faceted.

Phase I studies in humans have demonstrated that fludarabine phosphate is rapidly converted
to the active metabolite, 2-fluoro-ara-A, within minutes after intravenous infusion.
Consequently, clinical pharmacology studies have focused on 2-fluoro-ara-A pharmacokinetics.
After the five daily doses of 25 mg 2-fluoro-ara-AMP/m2 to cancer patients infused over 30
minutes, 2-fluoro-ara-A concentrations show a moderate accumulation. During a 5-day treatment
schedule, 2-fluoro-ara-A plasma trough levels increased by a factor of about 2. The terminal
half-life of 2-fluoro-ara-A was estimated as approximately 20 hours. In vitro, plasma protein
binding of fludarabine ranged between 19% and 29%.

CAMPATH

Campath-1H is a humanized fusion protein that is directed to CD52 antigen that is expressed
on all lymphocytes, monocytes and macrophages. It has very potent immunosuppressive property
and is effective for prevention of graft-versus-host disease. 30 mg/day of CAMPATH will be
given intravenously over 2 hours on days -4, -3 and -2. The most commonly reported adverse
reactions are infusion reactions fever, chills, hypotension, urticaria, nausea, rash,
tachycardia, dyspnea), cytopenias (neutropenia, lymphopenia, thrombocytopenia, anemia), and
infections (CMV viremia, CMV infection, other infections). In clinical trials, the frequency
of infusion reactions was highest in the first week of treatment. Other commonly reported
adverse reactions include vomiting, abdominal pain, insomnia and anxiety. The most commonly
reported serious adverse reactions are cytopenias, infusion reactions, and
immunosuppression/infections. About 30 minutes before the patient gets Campath, he/she will
be given other medications (such as acetaminophen or diphenhydramine, given orally, not IV)
to help reduce side effects.

Inclusion Criteria:

1. Age ≥ 18years and ≤ 60 years at the time of pretransplant evaluation.

2. Definitive diagnosis of sarcoidosis in pathologic specimen.

3. Patients who failed to respond to conventional treatment of at least 3 months duration
with corticosteroids (equivalent dosage of prednisone 1.0mg/kg/day to start). Patients
must also have failed two or more of the followings: TNF inhibitors (etanercept,
infliximab), methotrexate, azathioprine, 6-MP, cyclosporin, tacrolimus, mycophenolate
mofetil, gold, dapsone, colchicine, chloroquine/hydroxychloroquine or any other
immunosuppressive or modulating drugs.

4. Failure of therapy defined by (not caused by unrelated conditions) any one of
following:

- Progressive pulmonary disease (stage II or III) defined by decline in pulmonary
function (DLCo, VC or FEV1) of 15% or more over 12 months.

- Progressive CNS disease (worsening symptoms such as paraparesis or medically
refractory seizure).

- Persistent peripheral neuropathy (one of following):

1. Persistent muscle weakness Grade 3/5 or worse (MRC) in at least one movement
(e.g. ankle dorsiflexion) in two limbs.

2. Persistent cranial nerve involvement such as persistent facial diplegia.

3. Persistent incapacitating sensory loss (e.g. gait ataxia, falls > 1/month).

- Progressive loss of vision.

- Persistent hypercalcemia.

5. Cardiac sarcoidosis that is proven by cardiac biopsy or cardiac MRI.

Exclusion Criteria:

1. Alternative diagnosis.

2. Noncompliance to medical care.

3. > 10 pack-year history of cigarette smoking if lung disease is the major problem.

4. Poor performance (PS) status (ECOG >2) at the time of entry, unless decline of PS is
due to the disease itself.

5. Significant end organ damage such as:

1. Overt congestive heart failure (NYHA Class III or IV).

2. Active ischemic heart disease, s/p myocardial infarction within 6 months, s/p
unstable angina within 3 months, s/p CVA within 6 months, s/p hospitalization for
CHF within 3 months.

3. Untreated life-threatening arrhythmia.

4. Pulmonary hypertension > 40 mmHg.

5. End-stage lung disease (TLC < 55%, FVC < 55%, or DLCO < 40% of predicted value).

6. Serum creatinine > 2.5 or creatinine clearance < 30 ml/min.

7. Liver cirrhosis, transaminases > 3x normal or bilirubin > 2.0 unless due to
Gilbert's disease.

6. HIV positive.

7. Uncontrolled diabetes mellitus, or any other illness that in the opinion of the
investigators would jeopardize the ability of the patient to tolerate aggressive
treatment.

8. Prior history of malignancy except localized basal cell or squamous skin cancer. Other
malignancies for which the patient is judged to be cured by local surgical therapy,
such as (but not limited to) head and neck cancer, or stage I or II breast cancer will
be considered on an individual basis.

9. Positive pregnancy test, inability or unable to pursue effective means of birth
control, failure to willingly accept or comprehend irreversible sterility as a side
effect of therapy.

10. Significant psychological issues, social issues, psychiatric illness or mental
deficiency making compliance with treatment or informed consent impossible.

11. Inability to give informed consent.

12. Major hematological abnormalities such as platelet count less than 100,000/ul, ANC
less than 1000/ul.