FDA Approves Silicone Oil for Retinal Reattachment
The FDA today announced approval of silicone oil, a new product for reattaching the retina in certain complicated cases of retinal detachment. The retina can become detached from within the eye through injury or disease, including AIDS. If untreated, this can result in blindness.
In clinical studies of patients with complicated retinal detachment, the silicone oil product, Adatomed Silicone Oil, was successful in reattaching the retina in 60 to 75 percent of patients into whose eyes it was injected.
Each year, a small number of people with retinal detachment, including many people with AIDS, go blind because standard surgical procedures don't work," said FDA Commissioner David A. Kessler, M.D. "Silicone oil offers a new alternative that could save their sight."
The oil was approved to treat complicated retinal detachments that cannot be corrected with standard surgery. It is the most effective treatment for retinal detachment related to cytomegalovirus (CMV) retinitis, which affects many people with AIDS.
The oil is designed to be used in conjunction with, or following, other standard surgical procedures. It is a sterile, clear, colorless liquid that is injected into the eye and mechanically holds the retina in place until it reattaches to the inner surface of the eye. It is made by Adatomed of Germany, a division of Chiron Vision Corporation, Irvine, California.
The oil is not intended to remain in the eye permanently. The product labeling recommends that in most cases it be removed within a year after surgery, depending on the risk of redetachment. With AIDS patients, to minimize the number of surgeries these patients often undergo, it need not be removed.
FDA approved the product based on a review of laboratory and clinical studies of safety and effectiveness conducted by the manufacturer, on studies reported in the scientific literature, and on the unanimous recommendation of its Ophthalmic Devices Panel of the Medical Devices Advisory Committee.
Chiron Vision studied 155 patients at 11 medical centers in the United States. In addition, 299 patients were studied in Europe as part of a Silicone Oil Study Group. The retina was successfully reattached in 60 to 75 percent of patients treated with the oil. In about 80 percent of these patients, visual acuity either improved or stayed the same after the surgery. Normally, vision deteriorates in people with complicated retinal detachment.
Reattachment rates in people with AIDS-related CMV retinitis were as high as 96 percent. Visual acuity either improved or stayed the same in 57 percent.
Complications included development of cataracts, corneal diseases and glaucoma. All of these conditions can be treated with medical devices, drugs or surgery.
Adatomed Silicone Oil is a highly purified oil, not a silicone gel. Unlike silicone gel which can leak from a breast implant, the silicone oil is contained inside the eye.
In addition, unlike implants, which are meant to be permanent, the oil is intended to be removed from the eye once reattachment occurs and the eye is stable, further reducing exposure. The oil was tested extensively, and no adverse immunologic effects were reported.
Approximately 18,000 to 30,000 people in the United States have retinal detachment annually. An estimated 10 percent of those could be expected to benefit from silicon oil. Several hundred AIDS patients could also be expected to benefit from the oil each year.
FDA is one of the eight Public Health Service agencies in HHS.