Study: Rapamune Not Optimum for Some Kidney Transplant Recipients

The antirejection drug Rapamune (sirolimus) appears to prolong the delay that sometimes occurs before a transplanted kidney begins functioning, and thus may not be the optimum immunosuppressive choice for some kidney transplant patients, according to researchers at the University of California, San Francisco.

The researchers, reporting in the American Journal of Transplantation, said Rapamune had seemed like an ideal immunosuppressive for kidney recipients with delayed graft function, but said that when they started using it, they noticed that it took even longer for some transplanted kidneys to begin functioning.

Delayed graft function, which occurs in an estimated 20 percent of transplants of kidneys from cadaver donors, means that the recipient requires dialysis during the first week after transplantation.

In examining 132 cases of delayed graft function that occurred from 1997 to mid-2001, the researchers said they found that Rapamune had a "large and highly significant effect" on the time needed for the transplanted kidney to function.

They said recipients on Rapamune also were "twice as likely to remain on dialysis" after their transplant as recipients on other drugs.

"Because sirolimus appears to prolong delayed graft function, it may not be the optimal immunosuppressive choice in the delayed graft function setting," the researchers concluded.

Other Sources: American Journal of Transplantation