Randomized Study of Photodynamic Therapy Using Dihematoporphyrin in Patients With Corneal Neovascularization

OBJECTIVES: I. Demonstrate the safety and efficacy of dihematoporphyrin derivative (DHP) in laser photodynamic therapy (PDT) in patients with corneal neovascularization. II. Document the histopathologic mechanism of action in selected patients undergoing penetrating keratoplasty following PDT therapy for corneal neovascularization. III. Facilitate FDA product approval of DHP as a photosensitizing agent for laser treatment in these patients. IV. Explore the use of this photosensitizer for ocular and cutaneous basal cell and squamous cell carcinoma.

PROTOCOL OUTLINE: This is a randomized, placebo controlled study. Patients are randomized to 1 of 3 treatment arms: Arm I: Patients receive topical dihematoporphyrin derivative (DHP) every 3 hours on days -3 and -2. Patients undergo laser surgery on day 0. After photodynamic (PDT) therapy, patients receive topical prednisolone phosphate four times a day for 90 days. Ninety days following PDT, patients may undergo corneal transplantation. Arm II: Patients receive placebo topical gel and undergo sham laser surgery following arm I schedule, then receive topical prednisolone phosphate four times a day for 90 days. Patients may be crossed over to arm I if disease progression is observed. Arm III: Patients receive a compressed 1 day schedule of DHP with 5 doses in the morning and then undergo laser surgery in the evening. Patients are assessed on days 1, 7, 30, and 90 after PDT therapy. Completion date provided represents the completion date of the grant per OOPD records