The U. S. Food and Drug Administration (FDA), strongly warned the doctors about a particular type of anemia in patients being treated with Roche (ROG. VX) kidney- transplant drug.

This warning was posted on FDA's website warning health care professionals about the problem after recieving a letter from Roche. The warning has been added to the label of Cellcept, about the risk of pure red cell aplasia (PRCA), which previously carried boxed warning listing other risks.

"When PRCA occurs in a patient on multiple immunosuppressants, the relative contribution of the drugs to PRCA and the prophylaxis of rejection must be considered before a decision is made to discontinue a drug," according to the letter to healthcare professionals sent by Roche announcing the new warning.

The mechanism creating this side effect is not known yet, but some of the patients were also receiving other immunosuppressants which might have been the cause of aplasia, noted the manufacturer.

Other reported side effects include increased likelihood of opportunistic infection, fetal damage in pregnant women, and lymphoma in patients taking the drug as part of an immunosuppressive regimen.

The PRCA warning was issued after FDA's strong recommendation for warning labels on immunosuppressant drugs clearly reflecting the risk of infections.