Treating Cancer With Anti-mesothelin Modified Lymphocytes

Background:

- A possible new procedure for treating people with advanced cancer uses blood cells known
as peripheral blood cells. Once these cells are modified and grown in a laboratory, they can
be used to target and destroy cancer cells. Some cells can be modified to target a protein
called mesothelin that is found on some types of cancer cells. By blocking mesothelin, it is
expected that these cells will help shrink existing tumors. However, it is possible that the
cells will not have this effect. Researchers want to try this therapy on people who have
advanced cancer that has not responded to standard treatments.

Objectives:

- To test the safety and effectiveness of anti-mesothelin modified cells for advanced
cancer.

Eligibility:

- Individuals at least 18 years of age with advanced cancer that involves mesothelin and has
not responded to standard treatments.

Design:

  -  Participants will be screened with a physical exam and medical history. They will also
     have imaging studies before starting treatment. Blood and urine samples will be
     collected.

  -  Participants will have leukapheresis to collect peripheral blood cells. These cells
     will be modified for the treatment.

  -  Participants will have chemotherapy to prepare the immune system to receive the
     modified cells. The chemotherapy will take place for 1 week before the cell infusion.

  -  Participants will receive their modified cells as an infusion. They will also receive
     interleukin-2 to help boost their immune system response. The interleukin-2 will be
     given every 8 hours for up to 15 doses.

  -  Participants will recover from the infusion treatment in the hospital for at least 2
     weeks.

  -  The results of the treatment will be monitored with frequent follow-up blood tests and
     imaging studies.

Evaluate safety of anti-mesothelin CAR engineered PBL in patients receiving the protocol regimen.

Determine if anti-mesothelin CAR engineered PBL and aldesleukin to patients following the protocol regimen will result in clinical tumor regression.

Determine the in vivo survival of CAR gene engineered cells.

• Metastatic Cancer
• Pancreatic Cancer
• Mesothelioma

• Drug: Fludarabine
• Drug: Cycolphosphamide
• Biological: Aldesleukin

Background:

  -  We have constructed a single retroviral vector that contains a chimeric T cell receptor
     (CAR) that recognizes mesothelin, which can be used to mediate genetic transfer of this
     CAR with high efficiency (>  50%) without the need to perform any selection.

  -  In co-cultures with mesothelin expressing cells, anti-mesothelin transduced T cells
     secreted significant amounts of IFN-gamma with high specificity.

Objectives:

Primary Objectives:

  -  To evaluate the safety of the administration of anti-mesothelin CAR engineered
     peripheral blood lymphocytes in patients receiving a non- myeloablative conditioning
     regimen, and aldesleukin.

  -  Determine if the administration anti-mesothelin CAR engineered peripheral blood
     lymphocytes and aldesleukin to patients following a nonmyeloablative but lymphoid
     depleting preparative regimen will result in clinical tumor regression in patients with
     metastatic cancer.

Secondary Objective:

-Determine the in vivo survival of CAR gene-engineered cells.

Eligibility:

Patients who are 18 years of age or older must have

  -  Metastatic or unresectable cancer that expresses mesothelin;

  -  Previously received and have been a non-responder to or recurred after standard care;

Patients may not have:

-Contraindications for low dose aldesleukin administration.

Design:

  -  PBMC obtained by leukapheresis (approximately 5 times 10(9) cells) will be cultured in
     the presence of anti-CD3 (OKT3) and aldesleukin in order to stimulate T-cell growth.

  -  Transduction is initiated by exposure of approximately 108 to 5 times 108 cells to
     retroviral vector supernatant containing the anti-mesothelin CAR.

  -  Patients will receive a nonmyeloablative but lymphocyte depleting preparative regimen
     consisting of cyclophosphamide and fludarabine followed by intravenous infusion of ex
     vivo CAR gene-transduced PBMC plus IV aldesleukin (72,000 IU/kg q8h for a maximum of 15
     doses).

  -  Patients will undergo complete evaluation of tumor with physical examination, CT of the
     chest, abdomen and pelvis and clinical laboratory evaluation four to six weeks after
     treatment. If the patient has SD or tumor shrinkage, repeat complete evaluations will
     be performed every 1-3 months. After the first year, patients continuing to respond
     will continue to be followed with this evaluation every 3-4 months until off study
     criteria are met.

  -  The study will be conducted using a Phase I/II optimal design. The protocol will
     proceed in a phase 1 dose escalation design. Initially, the protocol will enroll 3
     patients in each dose cohort unless one patient experiences a dose limiting toxicity
     (DLT). Should a single patient experience a dose limiting toxicity at a particular dose
     level, additional patients would be treated at that dose to confirm that no greater
     than 1/6 patients have a DLT prior to proceeding to the next higher level. If dosing is
     escalated to cohort 10, 6 patients will be accrued to this cohort in order to further
     characterize the safety of the maximum tolerated dose prior to starting the phase II
     portion. If a level with 2 or more DLTs in 3-6 patients has been identified, three
     additional patients will be accrued at the next-lowest dose, for a total of 6, in order
     to further characterize the safety of the maximum tolerated dose prior to starting the
     phase II portion. If a dose limiting toxicity occurs in the first cohort, that cohort
     will be expanded to 6 patients. If 2 DLTs are encountered in this cohort, the cell dose
     will be reduced for two de-escalation cohorts. Once the MTD has been determined, the
     study then would proceed to the phase II portion. Patients will be entered into two
     cohorts based on histology: cohort 1 will include patients with mesothelioma, and
     cohort 2 will include patients with other types of cancer that express mesothelin.

  -  For each of the 2 strata evaluated, the study will be conducted using a phase II
     optimal design where initially 21 evaluable patients will be enrolled. For each of
     these two arms of the trial, if 0 or 1 of the 21 patients experiences a clinical
     response, then no further patients will be enrolled but if 2 or more of the first 21
     evaluable patients enrolled have a clinical response, then accrual will continue until
     a total of 41 evaluable patients have been enrolled in that stratum.

  -  The objective will be to determine if the combination of low dose aldesleukin,
     lymphocyte depleting chemotherapy, and anti-mesothelin CAR-gene engineered lymphocytes
     is able to be associated with a clinical response rate that can rule out 5% (p0=0.05)
     in favor of a modest 20% PR + CR rate (p1=0.20).

-  INCLUSION CRITERIA:

       1. Metastatic or unresectable measurable cancers that express mesothelin.
          Epithelial mesotheliomas and pancreatic cancers do not need to be assessed for
          mesothelin expression since all of these tumors have been shown to express
          mesothelin.

       2. Patients must have previously received at least one systemic standard care (or
          effective salvage chemotherapy regimens) for metastatic or unresectable disease,
          if known to be effective for that disease, and have been either non-responders
          (progressive disease) or have recurred.

       3. Greater than or equal to 18 years of age.

       4. Willing to sign a durable power of attorney

       5. Able to understand and sign the Informed Consent Document

       6. Clinical performance status of ECOG 0 or 1.

       7. Life expectancy of greater than three months.

       8. Patients of both genders must be willing to practice birth control from the time
          of enrollment on this study and for up to four months after receiving the
          preparative regimen.

       9. Serology:

            1. Seronegative for HIV antibody. (The experimental treatment being evaluated
               in this protocol depends on an intact immune system. Patients who are HIV
               seropositive can have decreased immunecompetence and thus be less
               responsive to the experimental treatment and more susceptible to its
               toxicities.)

            2. Seronegative for hepatitis B antigen, and seronegative for hepatitis C
               antibody. If hepatitis C antibody test is positive, then patient must be
               tested for the presence of antigen by RT-PCR and be HCV RNA negative.

            3. Women of child-bearing potential must have a negative pregnancy test
               because of the potentially dangerous effects of the preparative
               chemotherapy on the fetus.

      10. Hematology:

            1. Absolute neutrophil count greater than 1000/mm(3) without the support of
               filgrastim.

            2. WBC (>  3000/mm(3)).

            3. Platelet count greater than 100,000/mm(3).

            4. Hemoglobin greater than 8.0 g/dl.

      11. Chemistry:

            1. Serum ALT/AST less or equal to 2.5 times the upper limit of normal.

            2. Serum creatinine less than or equal to 1.6 mg/dl.

            3. Total bilirubin less than or equal to 1.5 mg/dl, except in patients with
               Gilbert's Syndrome who must have a total bilirubin less than 3.0 mg/dl.

      12. More than four weeks must have elapsed since any prior systemic therapy at the
          time the patient receives the preparative regimen, and patients' toxicities must
          have recovered to a grade 1 or less (except for toxicities such as alopecia or
          vitiligo).

EXCLUSION CRITERIA:

  1. Patients with sarcomatoid mesothelioma as mesothelin is not expressed in this type of
     mesothelioma.

  2. Women of child-bearing potential who are pregnant or breastfeeding because of the
     potentially dangerous effects of the preparative chemotherapy on the fetus or infant.

  3. Patients with known brain metastases.

  4. Patients receiving full dose anticoagulative therapy.

  5. Active systemic infections, coagulation disorders or other major medical illnesses of
     the cardiovascular, respiratory or immune system, myocardial infarction, cardiac
     arrhythmias, obstructive or restrictive pulmonary disease.

  6. Any form of primary immunodeficiency (such as Severe Combined Immunodeficiency
     Disease).

  7. Concurrent opportunistic infections (The experimental treatment being evaluated in
     this protocol depends on an intact immune system. Patients who have decreased immune
     competence may be less responsive to the experimental treatment and more susceptible
     to its toxicities).

  8. Patients with diabetic retinopathy.

  9. Concurrent Systemic steroid therapy.

 10. History of severe immediate hypersensitivity reaction to any of the agents used in
     this study.

 11. History of coronary revascularization or ischemic symptoms.

 12. Documented FEV1 less than or equal to 60% predicted tested in all patients.

 13. In patients over 60 years of age, LVEF of less than 45%