This study is the first step in testing the hypothesis that adding Photobac® Photodynamic Therapy to surgical removal of a glioblastoma or gliosarcoma will be both safe and effective. Photodynamic Therapy (PDT) combines light and a photosensitizer. PDT has been used to treat a variety of cancers with varying degrees of success. For the past thirty years Photolitec has been working to develop a treatment for glioblastoma or gliosarcoma using light and a photosensitizer. Photolitec's scientists were looking for a photosensitizer that: 1. has no significant systemic toxicity apart from some temporary skin photosensitivity, 2. crosses the blood brain barrier, 3. accumulates to a high level in glioblastoma and minimally in the brain, 4. is activated by the wavelength of light that penetrates most deeply into the brain, 5. minimizes any temporary skin photosensitivity. Preliminary testing indicates the Photolitec team has achieved these five goals. Photolitec is now able to offer a clinical trial based on the results of this work.
Twenty four hours before surgery the patient will receive an intravenous injection of Photobac®. This will make the brain tumor sensitive to light. Lighting up the brain using a low power near infrared laser will kill cells that contain Photobac®. Photobac® crosses the blood brain barrier. Compared to the brain at 24 hours after injection, the tumor holds significantly more Photobac®. This Selective retention by tumors is the reason PDT has proved a valuable weapon against other types of tumors. Once the surgeon has removed the tumor as completely as possible, the brain that bordered the tumor will be illuminated with near infrared light from a low power laser. This will destroy tumor cells hiding deep in the brain. Such cells cause tumor recurrence. The light treatment will add about one hour to the surgery. The Patient will be asleep during this procedure. The patient will receive standard post-surgical care during recovery.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
TREATMENT
Masking
NONE
Enrollment
30
Intravenous injection of Photobac® 24 hours before surgical removal of recurrent GBMF. Immediately after resection, the cavity will be treated with 50 joules/ square cm of 787nm light. This treatment will add a maximum of 50 minutes to the surgery
Roswell Park Cancer
Buffalo, New York, United States
RECRUITINGToxicity will be measured using CTCAE v5 ( Common Terminology Criteria for Adverse Events
•A dose limiting toxicity (DLT)will stop the escalation. A DLT includes all greater than or equal to grade 3 non-hematological toxicities and all greater than or equal to grade 4 hematological toxicities per CTCAE v 5.0
Time frame: .up to 24 hours
The Maximum Tolerable drug Dose (MTD) will be determined by evaluating the safety of a fixed light dose and escalating drug dose
The MTD will be determined by first discovering the dose limiting toxicity ( DLT). As defined above and following the procedure for determining the MTD from the DLT found in the protocol. It is expected that the DLT may be acute neurotoxicity caused by brain swelling.
Time frame: up to one week
Measure the Photobac concentration in blood.
Photobac® concentration in blood will be measured by drawing blood at various time points. The blood will be spun down and the concentration in the serum measured spectroscopically. Non-linear regression will be used to determine the clearance rate constants from these data.
Time frame: up to12 weeks
Measure Photobac® concentration in tumor tissue removed during resection and in the bed of the tumor both before and after ligh treatment.
The tissue samples will be subject to chemical extraction of the Photobac®. Photobac® concentration in the extract will be measured spectroscopically.
Time frame: 1 hour
Time of Progression Free Survival
The duration of progression free survival will be assessed by a Roswell neuroradiologist using RANO criteria.
Time frame: up t o18 months
Overall survival from time of diagnosis
Patients will be followed for the duration of the study and if possible until death.
Time frame: up to 18 months
Duration and severity of skin photosensitivity t osimulated sunlight .
If the patient's condition permits, a solar simulator will be used to assess the patient's skin photosensitivity .The severity and duration of sensitivity will be assessed using the Draize scale. The Draize scale ranges from zero indicating no reaction to 4 indicating a severe reaction. Two numbers will be reported one for erythema and the second for edema
Time frame: 1 week
Assess patterns of treatment failure for any association with the drug dose
Duration of survival and progression free survival will be examined for evidence of a Photobac® dose dependant response.
Time frame: up to 15 months.
Measure Stat 3 Crosslinking as a quantitative marker of singlet oxygen tissue damage
The samples of tissue taken from the tumor bed will be assayed for the degree of stat 3 crosslinking. Stat3 crosslinking is caused by singlet oxygen damage and is expected correlate with the PDT dose.
Time frame: 1 hour
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