Corneal Neovascularization — Randomized Study of Photodynamic Therapy Using Dihematoporphyrin in Patients With Corneal Neovascularization
Citation(s)
Chames MA, Sheppard JD, Mittal DC, et al : A rabbit model for argon laser photodynamic therapy of corneal neovascularization utilizing topical dihematoporphyrin. Investigative Ophthalmology and Visual Science 36(1): 146, 1995.
Cox KW, Sheppard JD, Lattanzio FA, et al : Photodynamic therapy of corneal neovascularization using topical dihematoporphyrin ester. Investigative Ophthalmology and Visual Science 38: S512, 1997.
Lattanzio F, Rusch A, Sheppard J, et al : Documentation of corneal neovascularization by quantitative video fluorescein angiography. Investigative Ophthalmology and Visual Science 37: S546, 1996.
Mittal DC, Chames MS, Sheppard JD, et al : Distribution of dihematoporphyrin in rabbit cornea, iris, aqueous humor and plasma after topical intravenous administration. Investigative Ophthalmology and Visual Science 36(13): 2564, 1995.
Sheppard JD, Chames MA, Clarke KC, et al : Argon laser photodynamic thrombosis of human corneal neovascularization utilizing intravenous dihematoporphyrin. Investigative Ophthalmology and Visual Science 35(4): 1350, 1994.
Williams PB, Sheppard JD, Chames MA, et al : Distribution of dihematoporphyrin in rabbit cornea, iris, aqueous humor and serum after topical vs intravenous administration. Journal of Clinical Pharmacology 35(10): 936, 1995.
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.
