Updated recommendations are provided for the statistical analysis of adhesion scores and results
The FDA has published the draft guidance for industry entitled, ‘Assessing Adhesion with Transdermal Delivery Systems and Topical Patches for ANDAs.’ This draft guidance provides updated recommendations for the design and conduct of in vivo studies evaluating the adhesive performance of a topical patch or a Transdermal Delivery System (collectively, TDS) submitted in support of an Abbreviated New Drug Application (ANDA). Updated recommendations are provided for the statistical analysis of adhesion scores and results. Expanded considerations relating to adhesion study designs are also discussed, including the evaluation of TDS adhesion in a study that also evaluates bioequivalence with pharmacokinetic endpoints.
The recommendations described in this draft guidance, which apply to all TDS products submitted in ANDAs, supersede only those recommendations (previously published in individual product-specific guidances) related to evaluating TDS adhesion in vivo. The FDA suggests that applicants continue to consult the recommendations in product-specific guidance documents for recommendations on other in vivo studies (e.g. related to evaluating TDS irritation or sensitisation) that may be necessary to support the submission of an ANDA for a proposed generic TDS drug product. The draft guidance can be accessed at: http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM504157.pdf