Cinacalcet drug more successful than a placebo in treating hyperparathyroidism

The research, led by Dr. Kevin Martin, director of the division of nephrology at Saint Louis University School of Medicine, showed a new drug called Cinacalcet was more successful than a placebo in treating hyperparathyroidism, a potentially harmful side effect of kidney disease.

Findings were published in the April 8 New England Journal of Medicine. Researchers at Harvard School of Medicine also participated in the trial.

"Current treatments are useful, but they are not uniformly effective," Dr. Martin said. "This gives doctors one more tool to use with dialysis patients."

The parathyroid glands regulate the amount of calcium and phosphorous in the blood through the production of parathyroid hormone. When the glands become overactive-a common side effect of kidney disease-the excess hormone they produce can cause calcium and phosphorous to be stripped from the bones and pulled into the bloodstream. In addition to weakening the bones, this can clog arteries and lead to cardiovascular problems.

Traditionally, doctors have treated the condition by giving patients calcium and vitamin D supplements to strengthen the bones. The new drug works by fooling the parathyroid glands into thinking the levels of calcium in the bloodstream are higher than they actually are, so the glands stop producing extra parathyroid hormone.

During the 26-week trial, Cinacalcet was given to 371 patients, and 370 received a placebo. Forty-three percent of those who received the drug showed normal parathyroid hormone levels at the end of the trial, versus just five percent of those who got the placebo.