Triamcinolone Acetonide Plus Laser Therapy to Treat Age-Related Macular Degeneration
This study will test the safety and effectiveness of combining a laser treatment called photodynamic therapy, or PDT, with injections into the eye of the steroid triamcinolone acetonide for treating age-related macular degeneration (AMD). The macula is the part of the retina in the back of the eye that determines central or best vision. AMD can severely impair central vision, affecting a person's ability to read, drive, and carry out daily activities. This vision loss is caused by the formation of abnormal blood vessels behind the retina that leak blood under the macula. PTD stops the growth of these blood vessels and slows the rate of vision loss; however, it has only a temporary effect and does not work in all patients. Furthermore, it may actually cause some swelling and re-growth of blood vessels. Triamcinolone acetonide can help lessen swelling and scarring.
Patients 50 years of age and older with AMD may be eligible for this study. Candidates are screened with a medical history, medical evaluation, and eye examinations (see below). Participants are randomly assigned to one of three treatment groups: 1) PDT plus 1 mg TAC-PF; 2) PDT plus 4 mg TAC-PF; or 3) PDT plus sham injection (a syringe with no needle is pressed against the eye). Treatments are given the day the patient enrolls in the study and then every 3 months for 2 years, as long as the therapy is thought beneficial. Patients who must discontinue TAC-PF injections may still be treated with PDT if medically necessary. In addition to treatment, patients undergo the following tests and procedures:
- Eye examination: Visual acuity and eye pressure are measured, and the lens, retina, pupils and eye movements are examined.
- Fundus photography: Photographs of the back of the eye are taken using a special camera with a bright flash.
- Lens photography: Photographs of the lens are taken to look for development of cataracts.
- Fluorescein angiography: Pictures of the retina are taken to look for abnormal blood vessels. A yellow dye is injected into an arm vein and travels to the blood vessels in the eyes. The retina is photographed using a camera that flashes a blue light into the eye. The pictures show if any dye has leaked from the vessels into the retina, indicating possible blood vessel abnormality.
- Optical coherence tomography: This test uses light to produce a 2-dimensional cross-sectional picture of the retina. The patient looks into a machine called an optical coherence tomograph at a pattern of flashing and rotating red and green lights, first with one eye and then the other.
- PDT: A needle is placed in an arm vein and a drug called verteporfin (Visudyne® (Registered Trademark)) is infused into the vein over 10 minutes. After 15 minutes, the eye is anesthetized with numbing drops. A special contact lens is then placed on the eye and the laser beam is directed to the eye for 83 seconds.
- TAC-PF or injections (for those in the TAC-PF treatment groups): Numbing and anesthetic drops are placed on the surface of the eye before injection of TAC-PF. Another anesthetic is then applied to the lower part of the eye with a cotton swab. After a few minutes, TAC-PF is injected into the vitreous (jelly-like substance inside the eye). Patients receiving sham injections undergo the identical procedure, except a syringe with no needle is pressed against the eye to seem like a real injection. All patients receive antibiotic drops to put in their eye for 2 days after each treatment. Patients return to the clinic anytime from 2 to 7 days after each treatment for a check of vision, eye pressure, and treatment side effects.
Patients are seen in the clinic for additional checks at 4 weeks and 4 months after the first treatment.
Drug: Triamcinolone Acetonide
|Study Design:||Primary Purpose: Treatment|
|Official Title:||Multi-Center, Randomized, Phase II/III Clinical Trial to Study the Effects of Preservative-Free Triamcinolone Acetonide as an Adjunct to Photodynamic Therapy in Participants With Neovascular Age-Related Macular Degeneration|
|Study Start Date:||December 2004|
|Estimated Study Completion Date:||December 2006|
Age-related macular degeneration (AMD) represents the most common cause of blindness in persons over the age of 50. The major cause of vision loss in this disease is due to the development of choroidal neovascularization. Several clinical trials have shown that eyes with neovascularization portending 4 disc areas or less or all lesions with predominately classic composition (lesions having at least 50% of vessels which can be readily demarcated with fluorescein angiography) can benefit from treatment with photodynamic therapy (verteporfin - PDT). However, this treatment only results in a reduction in the number of participants who suffer moderate and severe vision loss. Few participants demonstrate an improvement in visual acuity.
Histopathologic studies have demonstrated the presence of an inflammatory response in the retina and choroid of participants with choroidal neovascularization as well as in eyes receiving verteporfin - PDT. Therefore, the use of triamcinolone acetonide, which possesses anti-inflammatory as well as anti-angiogenic properties, may be beneficial in participants with neovascular AMD undergoing verteporfin - PDT.
This study will be organized as a controlled, participant masked, randomized, multi-center Phase II/III study that will investigate the efficacy of a preservative - free intravitreal formulation of triamcinolone acetonide (TAC-PF) in AMD participants undergoing verteporfin - PDT. Unlike studies that use steroids containing benzyl alcohol, this study will evaluate preservative-free steroids. Three hundred participants with neovascular AMD, undergoing verteporfin - PDT, will be randomly assigned to receive either a sham intravitreal injection, a 1 mg intravitreal injection of TAC-PF, or a 4 mg intravitreal injection of TAC-PF. Depending on a participant's response, treatments as randomized, may be repeated at 3-month intervals. Participants will complete a maximum of 2 years of follow-up.
The primary efficacy outcome measure is the proportion of participants who experience a moderate vision loss defined as a drop of greater than or equal to 15 letters in best-corrected visual acuity from baseline verteporfin - PDT treatment to month 12. Secondary outcomes will include assessments of the safety of the adjunct therapy; additional vision changes observed between baseline, month 3, month 12, and month 24; lesion changes observed between baseline, month 3, month 12 and month 24; and changes observed in lens opacities between baseline, month 12, and month 24.