A Study of Anti-CTLA4 Antibody in People With Advanced Synovial Sarcoma

Approximately 750-900 people in the United States each year develop synovial sarcoma, a rare
form of cancer of connective tissue. This tumor frequently metastasizes to other parts of the
body such as the lungs. Chemotherapy can sometimes decrease the size of the recurrent tumors,
but these results are usually only temporary, and the tumors grow again.

We are trying to exploit some of the proteins made by synovial sarcoma (cancer-germ cell or
cancer-testis antigens) as targets for the immune system. Specifically, we are investigating
if immune-based therapy with anti-CTLA4 antibody once every 4 weeks for three treatments will
activate the immune system enough to attack recurrent synovial sarcoma. In this study the
tumor itself serves as the "vaccine" or source of protein, as we try to activate
tumor-fighting T cells with the anti-CTLA4.

Anti-CTLA4 takes the brakes off the immune system to allow otherwise hidden immune responses
to become more active. In so doing, there could be other side effects, such as immune system
attacks against the normal organs of the body. We will follow both the anti-tumor immune
responses with frequent blood tests and follow and treat side effects people develop on this
study to determine if anti-CTLA4 is worth pursuing in a larger number of patients with
synovial sarcoma or other sarcomas.

Inclusion Criteria:

- Histologically documented synovial sarcoma

- RECIST measurable metastatic or locally recurrent disease who have failed standard
treatment

- Expected survival of at least 6 months

- Weight at least 25 kg

- ECOG performance scale 0-2

- At least 3 weeks since major surgery, and at least 3 weeks since completing radiation
therapy or chemotherapy (6 weeks for patients receiving mitomycin)

- Resolution of toxicity from previous treatment to NCI-CTC grade 1 or less before
treatment

- Adequate bone marrow, renal and hepatic function

- Age at least 13 years

- Able and willing to give valid written informed consent

Exclusion Criteria:

- Clinically significant heart disease (NYHA Class III or IV)

- Other serious illnesses, e.g. serious infections requiring antibiotics or bleeding
disorders

- History of autoimmune disease

- Patients with a second cancer diagnosis in the last five years, except for basal cell
carcinoma, completely resected, or cervical carcinoma in situ (CIN), completely
resected

- Known HIV positivity

- Metastatic disease to the central nervous system for which other therapeutic options,
including radiotherapy, may be available

- Chronic use of immunosuppressive drugs such as systemic corticosteroids.

- Mental impairment that may compromise the ability to give informed consent and comply
with the requirements of the study

- Lack of availability for immunological and clinical follow-up assessments

- Participation in any other clinical trial involving another investigational agent
within 3 weeks prior to enrollment

- Pregnancy or breast feeding

- Refusal or inability to use effective means of contraception (all men, and women with
childbearing potential)