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.

Inclusion Criteria:

1. Age ≥ 18years.

2. Subject has a Karnofsky performance status ≥ 70 (i.e. the subject must be able to care for himself/herself with occasional help from others; refer to Appendix G).

3. Subject has pathologically confirmed diagnosis of glioblastoma or gliosarcoma.

4. Subject has recurrent or progressive tumor following standard therapy.

5. Subject has recurrent cerebral tumor that in the opinion of the treating neurosurgeon is surgically resectable.

6. Subject has the following clinical laboratory values obtained within 14 days prior to registration:

   Absolute neutrophil count (ANC) ≥ 1.5 x 109/L

   • Platelets ≥ 100 x 109/L Hemoglobin (Hgb) > 9.0 g/dL Plasma total bilirubin: ≤ 1.5 x ULN ALT and AST ≤ 2.0 x ULN Creatinine clearance >60 WBC ≥ 4000 INR ≤ 1.1 x ULN

7. Subject will have been off all anticoagulant therapy (e.g., warfarin, heparin, enoxaparin, rivaroxaban, apixaban, aspirin) for at least 5 days before surgery and Photobac® infusion.

8. No active bleeding or pathological condition that in the judgement of the principal investigator carries a high risk of bleeding

9. Subject of child-bearing potential "agrees to use adequate contraceptive methods (e.g., hormonal or barrier method of birth control; abstinence) prior to study entry and have a negative pregnancy test prior to starting study treatment. Should a woman become pregnant or suspect she is pregnant while she or her partner is participating in this study, she should inform her treating physician immediately.

10. Subject has completed radiation therapy (RT) and temozolomide (TMZ) for the treatment of their glioblastoma or gliosarcoma at least 30 days prior to entry

11. Participant must understand the investigational nature of this study and sign an Independent Ethics Committee/Institutional Review Board approved written informed consent form prior to receiving any study related procedure.

Exclusion Criteria:

1. Subject has serious concurrent infection or medical illness, which in the treating physician's opinion would jeopardize the ability of the subject to receive the treatment outlined in this protocol with reasonable safety.
2. Subject is pregnant or breast-feeding.
3. Subject has latex allergy.
4. Subject has received another chemotherapeutic or investigational agent in addition to radiation therapy and concomitant temozolomide treatment within 30 days of planned PDT.
5. Subject has persistent toxicity of prior therapy.
6. Subject has gliomatosis cerebri.
7. Subject has cerebral tumor that in the opinion of the treating neurosurgeon is unresectable.
8. Subject has brainstem, spinal cord or cerebellar involvement by tumor.
9. Subject has known human immunodeficiency virus (HIV) positivity or acquired immunodeficiency syndrome (AIDS) related illness or other serious medical illness.
10. Subject has contraindication to MRI scans or gadolinium contrast agent.
11. Subject has history of porphyria, hypersensitivity to porphyrin or porphyrin-like compounds or any other abnormal skin photosensitivity.
12. Subject is unwilling or unable to follow protocol requirements.
13. Subject has any condition which in the Investigator's opinion makes the subject unsuitable to receive the study drug. Must be reported.
14. Subject has any condition which in the treating neurosurgeon's opinion makes the subject unsuitable to undergo craniotomy for tumor resection.
15. Subject has received an investigational agent within 30 days prior to planned PDT.
16. Subject has midline shift > 1 cm.
17. Subject is unable to give consent to participate in the study.
18. Subject has a QTC interval > 470 milliseconds (CTCAE grade 1) using Frederica's QT correction formula.
19. Subject has serious concurrent infection or medical illness, which in the treating physician's opinion would jeopardize the ability of the subject to tolerate the added hour o anesthesia outlined in this protocol with reasonable safety.