Trial Information

Phase 1 Study in Humans Evaluating the Safety of Rectus Sheath Implantation of Diffusion Chambers Encapsulating Autologous Malignant Glioma Cells Treated With Insulin-Like Growth Factor Receptor-1 Antisense Oligodeoxynucleotide in 12 Patients With Recurrent Malignant Glioma

This trial will be an adaptation and continuation of a previously published trial,
reproducing the original study size of 12 patients. Modifications from the previous trial
include a modified oligodeoxynucleotide sequence and treatment at initial diagnosis, which
would occur with concomitant standard therapy in an additional Phase 1 trial as a
continuation if no rate-limiting toxicity is noted in the original Phase 1 arm. For
practical purposes, a standard Phase 1 dose-escalation study is not possible with the
current paradigm. Although we may have identified a distinct bioactive byproduct of
IGF-1R/AS ODN-induced tumor cell apoptosis (exosomes), it is difficult to perform a dose
escalation in a typical fashion. Also, antigen concentration can affect immune response in
a biphasic manner: too little or too much can dampen an immune response, so even if the
antigen or antigens were known, a typical pharmacologic dose escalation would not follow
typical pharmacokinetics. For these reasons, we have designed a follow-on Phase 1 arm in
which 32 patients will have therapy at initial surgery in 4 cohorts of 8 patients each. We
will vary chamber number and implantation duration for each of the four cohorts in the
additional Phase 1 arm. When we documented an increase in tumor infiltrating lymphocytes
after treatment in our original trial, this observation provided preliminary supporting
evidence that this therapeutic vaccine will elicit an adaptive immune response. We have
designed the Phase 1 arm to further elucidate an immune response with a quantitative
assessment of tumor specific T cells as well as circulating M2 macrophages before and after
treatment. The design of the Phase 1 phase of the trial will allow a statistical analysis
of both antigen dose (number of chambers) and time of exposure (chamber dwell time) as
either variable may relate to any toxicity or treatment response.

A summary of the treatment paradigm includes: Pre-operative plasma leukopheresis, then
surgery with tissue harvest and implantation of up to 10 chambers in the rectus sheath with
IGF-1R/AS ODN as previously reported within 24 hours of craniotomy plus one chamber
containing only phosphate buffered saline. Twelve patients treated for recurrent disease
will be assessed for safety of the treatment. If the safety profile is acceptable, the
trial will be followed by accrual of 32 patients in an additional Phase 1 trial as a
continuation over approximately 3 years prospectively from Thomas Jefferson University
Hospital and the Jefferson Hospital for Neuroscience. All patients who meet the eligibility
criteria and agree to participate in this study will be potential candidates for therapy.

Pre-Operative Preparation - Patients will consent to a plasma leukopheresis at least 3 days
prior to elective craniotomy. The PBMC will be stored for subsequent analysis of T cell
responses, the presence of IL-10-producing M2 macrophages, and dendritic cell (DC)
preparation. ELISPOT assays will be performed to measure T cell responses to autologous
tumor cells and allogeneic tumor cells (U118 tumor lysate) utilizing cross-primed DC to
assess both native anti-glioma immunity any acquired immunity after treatment. If U118
allogeneic glioma cells elicit a CTL response, this cell line may serve as an antigen source
for future serial vaccination protocols.

A pre-operative PET scan as a baseline against which we can compare post-treatment PET scans
as indicated.

Surgery and Tumor Cell Retrieval - Craniotomy and MRI-based image guided tumor resection
will be performed on all study patients by an experienced neurosurgeon . All tested
malignant gliomas obtained from craniotomies performed at Thomas Jefferson University have
expressed the IGF-1R (M. Resnicoff, personal communication). During resection, viable tumor
tissue will be confirmed by pathologic examination of frozen sections, and then sent to a
BL-2 facility for disaggregation and plating in culture. Permanent section analysis will
include an IGF-1R immunostain to determine the presence of IGF-1R. Once the cells are
attached, cells will immediately be treated with IGF-1R/AS ODN. Tumor cells will be
incubated with IGF-1R/AS ODN for a maximum of 6 hours and 106 cells will be then be loaded
into each chamber and a target maximum of 10 chambers prepared. For all combination lot
productions, two additional irradiated chambers and 300 ul of treated autologous tumor cells
will be sent to microbiology for assessment of sterility according to FDA requirements.
Greater than 5 and less than 10 chambers will be scored as a minor protocol violation.
Recovery of no viable cells will be grounds for disenrollment from the protocol. Prior to
implantation, the chambers will be irradiated with 5 Gy of X-irradiation as previously
described. An additional tumor sample will be flash-frozen for exploratory research
objectives. At the time of craniotomy the surgeon will create an abdominal acceptor site
for subsequent diffusion chamber implantation in the rectus sheath. This implantation site
was chosen for the following reasons: (1) it yielded objective favorable biological
responses in the prior human Phase 1 trial; (2) this site will easily accommodate multiple
chamber implantations; (3) this site should elicit a strong host response due to the extent
of the wound, the introduction of a foreign body and its contents, the vasculature of the
rectus sheath and muscle, and the favorable inguinal node lymphatic drainage from this site;
and (4) exposure of the rectus sheath and muscle is familiar to neurosurgeons all of whom
commonly perform ventricular-peritoneal shunts.

Biodiffusion Chamber Implantation/Explantation - Autologous tumor cell preparation,
encapsulation in the biodiffusion chambers, irradiation, and chamber
implantation/explantation are all procedures detailed in the Standard Operating Procedures
Manual for IND #14379 (SOP 001). Briefly, at bedside in the intensive care unit the patient
is sedated with intravenous Midazolam (Versed, 0.05 mg/kg repeated every 2 - 3 minutes to
adequate sedation up to a maximum dose of 0.2mg/kg) and and Fentanyl (Sublimaze, 5mg which
may be repeated every 5 minutes to a maximum dose of 20mg) and the wound infiltrated with up
to 30 cc of 0.5% bupivicaine. With appropriate local anesthesia and sedation, the wound
prepared at surgery is re-opened through the rectus sheath and up to 10 chambers are
implanted between the rectus sheath and rectus muscle. The sheath is then re-approximated
with 2-0 vicryl sutures and the skin re-approximated with 3-0 nylon sutures.The 24 hour
period of implantation was chosen based on the favorable safety profile and promising
biological responses noted in the previous human Phase 1 trial. Explantation involves the
same process the following day with chamber explantation and a four layer wound closure.

Follow-up MRI imaging schedule The MRI studies at days 28 and 56 are acknowledged as not
being done as standard of care because they would not reflect meaningful clinical data if
patients received only standard of care treatment. The first surveillance MRIs are usually
obtained around 3 months after surgery or other interventions such as radiation or
chemotherapy. After this experimental treatment, however, we anticipate radiographic
responses much earlier as documented in the prior human trial. In the prior trial, partial
or complete radiographic responses were documented anywhere from 2 to 27 weeks after
treatment. We interpret these early responses to be a reflection of an immune-mediated
biological response.

Follow-up PET imaging schedule PET scans are scheduled at the discretion of the investigator
to confirm disease progression.