Study: New Therapy May Reduce Number of Drugs Needed for Immunosuppression

Transplant patients today generally have to take a drug like cyclosporine or tacrolimus, and a steroid such as prednisone, for the rest of their lives.

While these drugs keep the immune system from attacking the new organ, they can also lead to kidney or pancreas failure, high blood pressure, heart disease, diabetes or other potentially serious complications.

Now, researchers report that in small studies using an antibody called Campath-1H, a substance that attaches to and kills B cells and T cells that fight things they perceive as foreign to the body, they have been able to eliminate the post-transplant steroids without causing organ rejection.

The theory is that by destroying the cells that cause rejection at the time the organ is transplanted, and then allowing the cells to come back naturally as the new kidney heals, there is less rejection response.

The University of Wisconsin, which did pioneering work over the last few years that showed the concept worked in primates, started the first human experiments last August.

Seven kidney recipients at University of Wisconsin have received two doses of Campath-1H, one at the time of transplant and another a day later, and then were put on low doses of the relatively new antirejection drug sirolimus.

Researchers said with an average of six months follow-up, the first six University of Wisconsin patients show no signs of rejection. The seventh just started showing some signs and is being treated.

The NIH study involved eight patients, four of whom got three doses of Campath-1H just before their transplants, and four who got two doses before and one dose afterward.

"No patients had any rejection in two weeks with no (steroids or immunosuppressive) drugs whatsoever," said Dr. Alan Kirk, who led that study. "That's unheard of." Subsequently, when some early signs of potential rejection were observed, patients were given modest doses of sirolimus and kept on it as their sole drug therapy.

Now, with follow-up ranging from one to 16 months, "all patients are alive and well and at home," Kirk said.

Although this research has been done thus far on kidney recipients, Dr. Hans Sollinger, chairman of the University of Wisconsin transplant program, said there every reason to believe it will work with other transplanted organs as well.