# Treatment of Glioblastoma: the combination of fluorescence guided surgery and photodynamic therapy

> **NIH NIH R44** · PHOTOLITEC, LLC · 2022 · $960,821

## Abstract

ABSTRACT:
 The previously funded STTR (Fast Track Phase I/II, preclinical studies) project (R41/R42 CA173980-01A)
helped us in developing desired NIR PS (Photobac) with a great potential for both cancer imaging and therapy.
An efficient method for the synthesis of Photobac was also established in a GMP facility. Following the US
FDA guidelines, the pharmacokinetic (PK), pharmacodynamic (PD) and toxicity of Photobac in various doses
were also investigated in mice, rats and dogs. Histopathology results did not show any organ toxicity. Photobac
even at a 20-fold higher than the therapeutic dose (single dose needed for the treatment) was not lethal. No
metabolite formation and organ toxicity even at higher than the desired therapeutic dose was observed. The
biodistribution of C-14 Photobac at variable time points was also determined in mice and rats [7, 8]. Results
with C-14 Photobac in rats and fluorescence results in mice suggest that Photobac crosses the blood brain
barrier (BBB).
 A positive pre-IND response from the US FDA on our request for the use of Photobac to treat Gliomas was
pleasing & exciting (Application # PIND 136905). As suggested by the FDA review committee, the revision of
human patient Phase I protocol has been accomplished. NIR PS Photobac has also received an “Orphan
Drug” status from the US FDA for imaging and therapy of Glioblastoma (fluorescence-guided surgery +
PDTof recurrence tumors) (# DRU-2017-6153), which further encouraged us to move this technology to
Phase I human clinical trials. To achieve our goal, the proposed study (SBIR: Preclinical and Clinical)) has
been divided into following aims:
Aim 1 (a): To investigate the PDT efficacy of Photobac in rat glioma model and using Simphotek’s proprietary
computational device FPDosi™ (Beeson et al. J. Biomed. Opt. 24(3), 035006, 2019) compare light dose to
experiments. Details are presented in the letter of support from Simphotek. Aim 1 (b): To compile the
Photobac CMC (chemistry, manufacturing and control), drug-formulation, stability of drug substance and drug
product, analytical details, PK/PD, toxicity, in vitro & in vivo data and Phase I clinical protocol for an IND
submission to the US FDA for fluorescence image guided surgery + PDT of glioblastoma. The cost of the IND
submission will be paid by Photolitec, LLC.
Aim 2: To compile the details of PS (Photobac)-customized NIR laser instrument (787 nm, developed with the
help of Biolitec) following the US FDA guidelines, and submit it for approval (combined IND-Aim 1].
Aim 3: To perform Phase I trial with Photobac-PDT, fluorescence-guided treatment (surgery + PDT) of
glioblastoma at a single light dose and variable drug doses for selecting the best treatment parameters.
Aim 4: To provide tissue samples from glioblastoma, corresponding non-tumor tissue, untreated tumors,
Photobac-PDT treated tumors and recurrent tumors after previous surgery, chemotherapy, radiation and
chemotherapy treatment, for Photobac specificity using...

## Key facts

- **NIH application ID:** 10569740
- **Project number:** 4R44CA247127-02
- **Recipient organization:** PHOTOLITEC, LLC
- **Principal Investigator:** WILLIAM R POTTER
- **Activity code:** R44 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $960,821
- **Award type:** 4N
- **Project period:** 2020-09-07 → 2023-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10569740

## Citation

> US National Institutes of Health, RePORTER application 10569740, Treatment of Glioblastoma: the combination of fluorescence guided surgery and photodynamic therapy (4R44CA247127-02). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10569740. Licensed CC0.

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