Doctors draw on biotechnology to treat eye disorder

July 10, 1992|By Liz Bowie | Liz Bowie,Staff Writer

The morning after Lois H. Edwards ended a 30-year teaching career, she started going blind.

She was driving with her husband and suddenly couldn't read the license plates or the street signs ahead. "This came like a shot out of hell," said the 63-year-old woman, who was beginning to lose sight at the center of her vision.

"The feeling of knowing suddenly you were losing your eyesight was a horror -- not being able to see to read, not being able to see color, not being able to see your husband's face was just a horror."

By a series of fateful twists and turns, the New York woman vTC ended up a week later in the offices of Dr. Bert M. Glaser, director of the Retina Center at St. Joseph Hospital in Towson, where she underwent an experimental treatment.

Yesterday, as she watched the leaves fluttering on a tree outside her window, she could only describe the restoration of her eyesight as "unbelievable."

The treatment Dr. Glaser administered involves a new biotechnology product being developed at St. Joseph, which is used to heal a hole that can develop in the center of the retina leaving only peripheral vision.

Like wallpaper lining the inside of a tennis ball, the retina lines the inside of the eye, but it can develop a hole in the center. As fluid in the eye leaks through the hole and behind the retina, it can pull back the edges of the retina.

The condition leaves a person without depth perception and unable to read or drive.

In the first clinical tests, conducted on 200 patients, the treatment has proved a startling success, restoring some vision in 85 percent of the cases, Dr. Glaser said.

Until the development of the treatment, he said, patients with the condition were told there was nothing that could be done to help them. At least 10,000 new cases of the condition occur each year, making it a significant cause of blindness in the United States.

Attempts to use laser surgery to seal the retina fail because it causes scar tissue to form around the most sensitive and important portion of the eye.

So Dr. Glaser and his colleagues began looking for a way to heal the retina without laser surgery. They found a compound called transforming growth factor-beta 2 (TGF-beta 2), a complicated name for a protein that occurs naturally in the human body in small quantities.

After tests on laboratory animals proved encouraging, Dr. Glaser looked for a source of TGF-beta 2 and found only one company that made it. Celtrix Pharmaceuticals Inc., a biotechnology company in Santa Clara, Calif., was researching its uses as a way to stimulate the healing of wounds.

During surgery on patients such as Mrs. Edwards and Barbara Christin, a 45-year-old attorney with the federal Energy Regulatory Commission, Dr. Glaser would take the fluid out of the eye, put some TGF-beta 2 on the retina and then fill the eye with a gas bubble. The bubble presses the retina back in place while it heals.

But it also leaves patients in some uncomfortable contortions during the two months of healing because they must keep their heads down -- between their knees -- for many hours a day to ensure that the bubble floats up against the back of the retina.

Mrs. Edwards learned to drink soda with a straw, watch television with the aid of mirrors and even make the long trips between New York and Baltimore -- all with her head down.

Despite the discomfort, it worked for both women. Ms. Christin said that before surgery, her eyesight was 20-200. Today, it is 20-25. "It has been like magic really," she said.

After two years of treating patients, Dr. Glaser published his initial findings in this month's issue of the journal Ophthalmology. The results have been dramatic, but the compound must go through at least two more years of testing and an arduous approval process at the U.S. Food and Drug Administration.

Celtrix, which holds patents on TGF-beta 2, expects a U.S. market of $5 million to $10 million a year once the compound is approved for commercial sale -- as early as late 1995 or 1996, said Sandra McNamara, vice president and chief financial officer for Celtrix.

TGF-beta 2 occurs naturally in the human body as a healing agent, but Celtrix extracts it from a particularly rich source -- cow bones.

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