Released by FDA: 6/1/00.  Posted by FDA:  7/17/00

Mr. Stephen W. Sherman 
Director, Advertising and Labeling 
Regulatory Affairs 
Alza Corporation 
1010 Joaquin Road 
P.O. Box 7210 
Mountain View, CA 94039-7210

RE:   NDA# 20-897 
         Ditropan XL (oxybutynin chloride) Extended Release Tablets 
         MACMIS ID#9025

Dear Mr. Sherman:

This letter concerns Alza Corporation’s (Alza) dissemination of a television broadcast advertisement for Ditropan XL (oxybutynin chloride) Extended Release Tablets.  The Division of Drug Marketing, Advertising, and Communications (DDMAC) reviewed this advertisement as part of its monitoring and surveillance program and concluded that it is misleading and therefore violates the Federal Food, Drug, and Cosmetic Act and applicable regulations. Our specific objections follow.

Presentation of Discontinuation Rates Minimizes Overall Presentation of Risk Information

“In studies, the most common side effect was dry mouth. Only 1% of patients stopped taking Ditropan XL for that reason.  Other side effects may include constipation, drowsiness, blurred vision, dizziness, diarrhea, and nausea.  Only 7% of patients discontinued due to side effects.”

The discontinuation statements included in your advertisement are selective presentations of the disclosed side effects that minimize the overall presentation of this risk information.  For instance, the statement that only 1% of patients discontinued drug treatment because of dry mouth is misleading because the ad does not also disclose that 61% of patients in clinical trials on Ditropan XL experienced dry mouth.  Therefore, the presentation of these discontinuation rates without accompanying contextual information is misleading.

On January 12, 1999, DDMAC raised this contextual risk disclosure issue to Alza in written comments on a proposed professional sales aid for Ditropan XL. 

Alza should immediately cease using this television advertisement and all other promotional materials for Ditropan XL that similarly minimize this side effect information in other presentations.  We should receive your written response no later than June 15, 2000, and it should list similarly violative materials, with a description of your method of discontinuation, and the discontinuation date.

Your response should be directed to Mark W. Askine, R.Ph., by facsimile at (301) 594-6771, or at the Food and Drug Administration, Division of Drug Marketing, Advertising, and Communications, HFD-42, Rm 17-B-20, 5600 Fishers Lane, Rockville, MD 20857. DDMAC reminds Alza that only written communications are considered official.

In all future correspondence, regarding this matter, please refer to MACMIS ID# 9025 in addition to the NDA number.

Sincerely,

Mark W. Askine, R.Ph. 
Regulatory Review Officer 
Division of Drug Marketing, 
   Advertising, and Communications

 

Joan Hankin, J.D.
Consumer Safety Officer 
Division of Drug Marketing, 
    Advertising, and Communications