Noven Pharmaceutical’s failure to address underlying system problems related to the collection and evaluation of manufacturing information from its Daytrana transdermal patches was cited in a recent FDA warning letter.

The Daytrana (methylphenidate) patch, which is approved to treat attention-deficit/hyperactivity disorder, is designed using Noven’s proprietary DOT Matrix technology. The part of the patch that contains the active ingredient consists of an acrylic adhesive and a silicone adhesive. Noven manufactures the product for Shire.

Following a June 2007 inspection of Noven’s Miami facility, the FDA cited the firm for two related issues. The first citation involved not establishing appropriate peel-force specifications for removing the patch’s release liner, the backing that is peeled off before the patch is applied. The protective release liner is fluoropolymer-coated polyester.

Lower peel-force values are associated with a reduced likelihood that the adhesive drug matrix sticks to the release liner when removed, a significant quality attribute of the product. There may be concern that Daytrana has excessive rates of adhesive transfer.

The agency said these problems could have been addressed during clinical development.

“In light of the lack of evaluation of the Daytrana patch liner release values, we are concerned about your firm’s global system(s) for gathering and analyzing data from clinical lot manufacturing which may impact critical quality attributes of other transdermal patch and transoral products you manufacture,” the FDA said in the letter.

Shire said it is committed to working with Noven to resolve the issues. It has provided Noven with expertise in quality control and quality assurance. However, Shire is evaluating options for retaining backup manufacturing capabilities as it does with all its products, it said.

The warning letter can be accessed at www.fda.gov/foi/warning_letters/s6632c.pdf.