
                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: WEDNESDAY, May 18, 1994                   TAG: 9405180089
SECTION: NATIONAL/INTERNATIONAL                    PAGE: A-6   EDITION: METRO 
SOURCE: Associated Press
DATELINE: WASHINGTON                                LENGTH: Medium

FDA RECHECKS STUDY RESULTS

The Food and Drug Administration is re-examining three common allergy drugs after Canadian researchers concluded they can promote cancer growth in laboratory mice, even at low doses.

In a study to be published today in the Journal of the National Cancer Institute, researchers at the Manitoba Institute of Cell Biology in Winnipeg report that cancer tumors grew faster and larger in mice injected with loratadine, astemizole and hydroxyzine, three antihistamines.

Two other tested antihistamines, doxylamine and cetirizine, were not found to stimulate cancer tumor growth, said Dr. Lorne J. Brandes, principal author of the study.

"I am very concerned about these findings, and so is the FDA," Brandes said.

An FDA scientist, who asked not to be identified, said the agency was taking the finding seriously and was conducting research on antihistamines and cancer. However, the scientist said that the relevance to human health of chemical stimulation of tumors in mice "is yet to be proven."

Brandes said he would not encourage people to stop using antihistamines, because benefits outweigh the risks. Patients "should use them for as short a period as possible and only when really needed," he said.

Astemizole is the main ingredient in Hismanal, manufactured by Janssen Pharmaceutica Inc. of Titusville, N.J. Loratidine is found in Claritin, made by Schering-Plough of Madison, N.J. Hydroxyzine is used in at least seven allergy products, but Brandes specifically linked his study with Atarax, made by the Roerig Division of Pfizer Inc. of New York.

All are prescription drugs used to treat symptoms of allergies and hay fever.

Brandes said he earlier gave the results of the study to FDA researchers and was told the federal agency was conducting new studies on effects of the antihistamines.

"I do believe they're doing a lot to investigate this," Brandes said of the FDA.

A statement from the FDA said that no human clinical studies support the results of Brandes' research.

"The agency does not believe, therefore, that changes in the drugs' labeling or approval status are warranted," the FDA statement said.

However, the FDA said it is trying to duplicate the results of Brandes' studies, including the use of other types of cancer, and may conduct epidemiological studies on patients with cancer.

by CNB