In the final year of the first Generic Drug User Fee Act (GDUFA I), FDA’s Office of Generic Drugs (OGD) is planning to prioritize the post-market evaluation of generics, work on the equivalence of complex generics and locally acting products, as well as new standards and computational and analytical tools.
The release of OGD’s regulatory science priorities on Thursday comes as 2016 saw a banner year for generic approvals, with 651 approvals (or 835 if tentative approvals are included), which was 159 more than the number of approvals for FY 2015 and 242 more than the agency approved in FY 2014.
FDA will also look to set the stage in the final year of GDUFA I for GDUFA II, which is expected to feature eight-month priority reviews for some generics and enhanced communications between industry and FDA, as well as a massive boost in the amount of user fees that industry will pay to FDA to further reduce the backlog of generic applications.
In terms of post-market evaluation goals, FDA plans to conduct research on understanding patient perceptions of generic drug quality and effectiveness, and verifying therapeutic equivalence via patient brand-to-generic switching studies.
“These investigations provide additional data in therapeutic areas where concern exists about the substitutability of generic drugs and allow FDA to verify that generic drugs are fully interchangeable, safe, and effective in comparison to their reference listed drug,” the agency said.
Ongoing activities include evaluating modified release formulations, identifying the role replicate design studies may add to bioequivalence determinations and piloting surveillance methodologies for generic drugs within FDA’s Sentinel program.
As far as OGD’s work on complex generics, the agency seeks to conduct research into making generic versions available in all product categories, including complex drugs with unique characteristics.
This research is intended to support the development of guidance and policy clarifying the Abbreviated New Drug Application (ANDA) pathway for complex products, such as drug-device combinations, transdermal systems, implants and parenteral microspheres, nanomaterials (e.g. liposomes and iron colloids) and products that contain complex mixtures and peptides, FDA says.
New guidance may also be forthcoming on transdermal irritation studies and human factors studies aiding the evaluation of product substitutability and robustness for drug-device combinations.
Additional research will dig into new bioequivalence methods and pathways for locally acting drugs, as up until now, the lack of efficient bioequivalence pathways for locally-acting drugs has limited the availability of generic drugs in this category, FDA says, which includes inhalation, topical dermatological, nasal, ophthalmic, gastrointestinal and otic drugs.
“This research priority includes evaluating in vitro alternatives to clinical endpoint bioequivalence studies. Often these in vitro alternatives are based on microstructure characterization (Q3 equivalence) for products that are qualitatively (Q1) and quantitatively (Q2) similar in formulation, with a research goal of guidance for Q3 bioequivalence approaches,” the report adds.
FDA also said it continues to prioritize research that supports the approval of abuse-deterrent formulations, improves the evaluation of excipients, increases the agency’s understanding of solid dispersions of low solubility drugs and supports equivalence of modified release solid oral dosage forms.
Manufacturing quality, via advances in process control, continuous manufacturing and quality metrics, as well as advancing analytical characterization and abuse-deterrent mechanisms are also priorities for the agency.
GDUFA Regulatory Science Priorities for Fiscal Year 2017