• 5/12/2001
  • San Francisco
  • Deena Beasley
  • Reuters

An experimental drug that stimulates cell growth can reduce the duration of severe mouth sores in cancer patients undergoing toxic treatments like chemotherapy, researchers said on Saturday.

“Currently, there are no approved or consistently effective treatments for severe mucositis. This is a potential breakthrough,” said Dr. Ricardo Spielberger, a staff physician at the City of Hope National Medical Center in Duarte, California, and lead investigator in a midstage clinical trial of the recombinant human keratinocyte growth factor, or KGF. KGF, a human protein shown to protect certain tissues from damage, is being developed by Amgen Inc., which sponsored the studies of the drug.

Mucositis, or severe inflammation of mucous membranes in the mouth and throat, is a serious and painful side effect of cancer therapy. Patients who develop the condition have difficulty swallowing, eating, drinking and talking. The mouth sores cause pain and lower the quality of life for patients but also make them more susceptible to infection, the researchers said. “Mucous membranes are affected by toxic cancer therapies because they are fast-dividing cells — like tumor cells,” explained Dr. Patrick Stiff of Loyola University in Chicago, a co-author of the study. He said mouth sores were the No. 1 complaint of lymphoma patients who could be successfully treated with intense doses of radiation therapy followed by stem cell transplants.

PROBLEM HALVED

In a trial of 129 of these patients, those who received injections of KGF, both before and after undergoing cancer therapy, experienced an average of four days of severe oral mucositis, compared with 7.7 days for patients who received a placebo, the investigators said. Patients who received a single dose of the drug before cancer treatment suffered mucositis for an average of five days. “We are able to provide these patients with a curative therapy, but there are lots of side effects. Now we are trying to alleviate some of those,” Stiff said.

In a separate Phase II trial, 64 patients with colorectal cancer were given either KGF or placebo in concert with two cycles of chemotherapy. The group receiving placebo had a 78 percent mucositis rate, compared with 32 percent in the KGF-treated group. The colorectal cancer study also found a reduction in the duration of oral mucositis — 10.2 days for the placebo vs. 3.4 days for KGF-treated patients.

Patients in both trials reported less pain and used less pain medication. They also needed less intravenous nutrition than other patients, the investigators said. In both studies, KGF was well tolerated. Minor side effects included skin rashes, flushing and swelling, and reversible increases in blood serum levels.

“Patients’ mouths become dry as the membrane thickens up, but that’s something we want to have happen,” Stiff said.

Amgen is currently conducting a pivotal-stage trial of KGF in lymphoma patients, and trials of the drug in other types of cancer, such as head-and-neck, are planned.