Texaphyrins


  • Photosensitizer: Lutetium Texaphyrine, Texaphyrine
  • Tradename: Lutrin™, Antrin™, Optrin™
  • Company Photosensitizer: Pharmacyclics
  • Clinical Application: Breast cancer, angioplasty, macular degeneration
  • Wavelength (nm): 732
  • Extinction Coefficient (M-1 cm-1): 2.5 105
  • Mode of Delivery: Intravenous
  • Delivery vehicle: Water-soluble
  • Typical Dose (mg kg-1): 0.6–7.2
  • Light Dose (J cm-2): 150
  • Time Post-Injection: 3–5 h
  • Duration of Skin Photosensitivity: Minimal

Texaphyrins are ‘Texas-sized’ porphyrins featuring a penta-aza core and are marketed by Pharmacyclics (Sunnyvale, CA, USA) as a photosensitizer (see http://www.pcyc.com). Under the trade name Lutrin™, lutetium texaphyrin is undergoing Phase II clinical trials as a possible therapy for breast cancer.
The main advantage of using texaphyrins as PDT agents is their strong absorbency at a much longer wavelength (732 nm) so that treatment can be carried out effectively on a larger tumour or at a greater depth.

The lutetium texaphyrin derivative, Antrin™, is also in Phase I clinical trials for angioplasty of atherosclerotic cardiovascular disease and the treatment and prevention of restenosis, while another derivative, Optrin™, is in Phase I trials for AMD.
In addition, the company is also developing radiosensitizers and chemosensitizers based on the texaphyrin framework with the radiation sensitizer, Xcytrin™, currently in Phase III clinical trials for the treatment of brain metastases and Phase I trials for newly diagnosed primary brain tumours[89].



Texaphyrins

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