September 27, 2019

The U.S. Food and Drug Administration announced today the availability of a draft revised guidance for industry (GFI) #171, “Demonstrating Bioequivalence for Soluble Powder Oral Dosage Form Products and Type A Medicated Articles Manufactured from Active Pharmaceutical Ingredients Considered to be Soluble in Aqueous Media.” This document describes how the agency intends to evaluate requests for waiving the requirement for performing in vivo bioequivalence studies (biowaivers) for animal drugs administered orally as soluble powders or as Type A Medicated Articles manufactured from active pharmaceutical ingredients (APIs) considered to be water soluble (i.e., the API will dissolve in water).

This guidance is applicable to generic investigational new animal drug (JINAD) files and to abbreviated new animal drug applications (ANADAs). Although the recommendations in this guidance refer to generic drug applications, the general principles described may also be applicable to new animal drug applications (NADAs), investigational new animal drug (INAD) files, and supplemental NADAs.  This guidance does not address Type A medicated articles manufactured from APIs considered to be insoluble in water.

In most cases, a sponsor seeking approval of a generic animal drug must demonstrate that there are no significant differences in the rate and extent of drug availability associated with the proposed generic and reference drug products when administered at the same dose under similar conditions. This is often demonstrated through in vivo studies. However, in certain circumstances, the demonstration of bioequivalence does not need to be established on the basis of in vivo studies, and can be demonstrated in other ways, such as through in vitro studies. The intent of this guidance is to lessen the approval burden for a generic animal drug product and reduce animal testing by establishing the conditions under which an in-life animal study would not be required to establish bioequivalence.

Today’s guidance document expands upon GFI #35, “Bioequivalence Guidance,” to include biowaivers for soluble powder oral dosage form products as well as Type A medicated articles manufactured from APIs considered to be water soluble.  This guidance offers particular focus on criteria for the waiver of the requirements for submitting in vivo bioequivalence study data. 

The FDA is accepting public comment on the draft guidance for 60 days from the date of publication in the Federal Register. To electronically submit comments to the docket, visit https://www.regulations.gov and type FDA-2004-D-0045 in the search box. For assistance in submitting electronic comments, please see Regulations.gov Help.  

To submit comments to the docket by mail, use the following address. Be sure to include docket number FDA-2004-D-0045 on each page of your written comments.

Dockets Management Staff 
HFA-305
Food and Drug Administration
5630 Fishers Lane, Room 1061
Rockville, MD  20852 

Comments will be accepted at any time, but should be submitted no later than November 29, 2019, to ensure that the FDA takes the information into consideration before making further decisions on this issue.

For more information:

• GFI #171: Demonstrating Bioequivalence for Soluble Powder Oral Dosage Form Products and Type A Medicated Articles Manufactured from Active Pharmaceutical Ingredients Considered to be Soluble in Aqueous Media
• GFI #35 “Bioequivalence Guidance”