SBIR-STTR Award

Photodynamic therapy (PDT), using hematoporphyrin derivative (HpD) or its more purified form, di-hematoporphyrin-ether (DHE), is presently undergoing extensive clinical trials PDT is based on the selective retention of HpD/DHE by neoplastic tissue and its ability to be photodynamically active. The therapeutic response obtained is a product of the HpD/DHE present in the tissue and the light it absorbs. Physiological factors such as tissue 0, content, pH, and temperature may also play a role in the therapeutic response.This Phase I study will develop a prototype single optical fiber probe that can measure(1) the light space irradiance in vivo,(2) the fluorescence of the HpD/DHE in vivo, and(3) the absorption dose rate and therapeutic dose in vivo.Such a probe would be useful in monitoring the photodynamic reaction in vivo and thereby provide for a more optimum treatment. The system would consist of a single quartz fiber for delivery of the fluorescence exciting light and to pick up the fluorescence signal. A ratio of selective wavelengths in the fluorescence emission will permit separation of HpD/DHE fluorescence from other background fluorescence.In Phase I, extensive pulmonary and animal clinical trials will be undertaken, along with further refinement of the instrumentation.National Cancer Institute (NCI)

Photodynamic Therapy (PDT) using photosensitive tumor localizing drugs and laser light is undergoing extensive basic, preclinical and clinical research. The therapeutic response obtained by PDT is a product of the photosensitizer concentration in the tissue and the light it absorbs. Physiological factors such as tissue O2 content, ph, and temperature may also play a role in determining the therapeutic response. It is the objective of this Phase-II project to further develop and test a Photodynamic Therapy (PDT) dosimeter system to improve the modality. This development will include (1) further refinement of a fiber optic isotropic probe for measuring the space irradiance in-vivo, (2) increasing the sensitivity of the fiber optic probe for simultaneously measuring the fluorescence of the photosensitizing drug in-vivo, (3) correlation of the measured parameters with biological response in a standardized animal model, (4) evaluation of detecting singlet oxygen emission at 1270nm as a dosimetry monitor and (5) preliminary evaluation of the usefulness of the instrument in patients undergoing PDT treatment for recurrent chest wall metastasis of breast cancer. In Phase-III the instrument will be further standardized, and controlled clinical trials undertaken to obtain FDA approval for commercialization.

Thesaurus Terms:
biomedical engineering, instrumentation clinically oriented, biomedical systems automated, patient monitoring (monitoring devices), neoplastic therapy, cancer chemotherapy, neoplastic therapy, cancer photoradiation therapy, neoplastic therapy, combination antineoplastic therapy, optics, fiber optics, photochemistry antineoplastic agents, dosage and route, dosage, drugs, pharmacology, bioavailability, models, mathematical, neoplasms of reproductive system, breast neoplasms, optics, lasers, optics, light emission, fluorescence, oxygen, singlet oxygen, photobiology, photosensitivity, radiation dosage and dosimetry, radiation therapy dosage, radiation, electromagnetic waves, visible light (380nm to 720nm), radiosensitizers animals, chordates, mammals, rodents, myomorpha, mice (laboratory), human, clinical, models, disease models