In an earlier study that involved 1,432 patients, 222 suffered heart problems, some of which were fatal.
America's drugs watchdog, the Food and Drug Administration, has issued a federal alert about the drugs, and will review their continued availability at a meeting next month. In the meantime, the FDA is advising doctors to keep dosages low.
The drugs are big business. In 2002, the latest year when figures are available, global sales had reached $8.1bn (lb4.2bn), an increase of 18 per cent on the previous year.
The drugs are routinely given to patients who are anaemic following chronic renal failure, cancer, chemotherapy treatment, or HIV and AIDS.
(Source: The FDA website).
E-news broadcast 12 April 2007 No.350 [Subscribe]