# Leveraging Model Master Files for Long-Acting Injectables

## TL;DR

This paper discusses how model master files can improve regulatory processes for long-acting injectable drug development.

## Contribution

The paper introduces potential applications of model master files in regulatory submissions for long-acting injectables.

## Key findings

- Model master files can support regulatory submissions through mechanistic and simulation models.
- Challenges and benefits of implementing model master files for LAIs were discussed.
- MMFs may enhance model sharing and regulatory consistency in drug development.

## Abstract

The U.S. Food and Drug Administration (FDA) and the Center for Research on Complex Generics (CRCG) hosted a public workshop on May 2–3, 2024, titled “Considerations and Potential Regulatory Applications for a Model Master File”. The workshop aimed to discuss the application of the Model Master File (MMF) concept in regulatory submissions that contain model integrated evidence (MIE), improving model sharing, model standardization, regulatory consistency, and regulatory efficiency. On Day 1, there was a session dedicated to MMF applications for long-acting injectables (LAIs). This perspective summarizes presentations, panel discussion, and small group discussion for the potential applications of MMFs in LAI product development, including case studies and potential situations in which MMFs can support regulatory submissions. The scientific presentations discussed the application of MMFs in mechanistic physiologically based pharmacokinetic (PBPK), multiphysics simulation, and population pharmacokinetics (popPK) models, as well as the potential utility of a model-integrated bioequivalence (MI-BE) framework. Additionally, challenges and considerations of implementing MMFs for LAIs were discussed in the panel and small groups. The anticipated benefits of MMFs are recognized among model developers, industries, and regulators.