A drug given to late-stage cancer patients to help ease the constipation brought on by morphine has been shown to extend their lives, researchers said.

Methylnaltrexone, approved by the US Food and Drug Administration in 2008 to treat opioid-induced constipation, could play a role in cancer therapy, according to researchers who presented their findings at the meeting of the American Society of Anesthesiologists in San Diego.

“Early on, we began to suspect that methylnaltrexone might inhibit cancer growth,” said Jonathan Moss, lead author of the study and professor of anesthesia and critical care at the University of Chicago.

“After more than a decade in the lab trying to assess how methylnaltrexone affects cancer, we have the first evidence that it can decrease tumor growth and extend survival in patients who respond to the drug.”

Retrospective analysis

The study was a retrospective survival analysis involving 229 patients across two randomized, controlled clinical trials on the relief of constipation for patients in the late stages of cancer and other terminal diseases.

Opioids like morphine are known to cause severe constipation that often cannot be relieved by traditional laxatives.

“In these two trials, 117 cancer patients received methylnaltrexone (marketed as Relistor) for opioid-induced constipation, while 112 were given a placebo,” said the study. AFP