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Reverse Engineering the 1-Month Lupron Depot®.

Jia Zhou1, Keiji Hirota1,2, Rose Ackermann1

  • 1Department of Pharmaceutical Sciences, The Biointerfaces Institute, University of Michigan, 2800 Plymouth Rd., Ann Arbor, Michigan, 48109, USA.

The AAPS Journal
|October 4, 2018
PubMed
Summary
This summary is machine-generated.

Reverse engineering of Lupron Depot® (LD) microspheres characterized its composition and attributes. This detailed analysis provides a roadmap for developing generic leuprolide poly(lactic-co-glycolic acid) microsphere formulations.

Keywords:
Lupron Depot®PLGA microspheresgeneric drugsleuprolidereverse engineering

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Area of Science:

  • Pharmaceutical Sciences
  • Biomaterials Science
  • Drug Delivery Systems

Background:

  • The 1-month Lupron Depot® (LD) is a benchmark long-acting injectable formulation for leuprolide.
  • Despite patent expiration, generic versions are unavailable due to manufacturing complexity.
  • Reverse engineering is crucial for understanding and replicating complex drug delivery systems.

Purpose of the Study:

  • To comprehensively reverse engineer the composition and critical attributes of Lupron Depot® (LD).
  • To identify key characteristics necessary for the development of generic leuprolide poly(lactic-co-glycolic acid) microspheres.
  • To establish a framework for the development of other generic PLGA microsphere formulations.

Main Methods:

  • Detailed chemical and physical characterization of LD microspheres and diluent.
  • Analysis included leuprolide, gelatin, and poly(lactic-co-glycolic acid) (PLGA) content and properties.
  • In vitro drug release, particle size, morphology, residual solvents, and moisture content were assessed.

Main Results:

  • PLGA and formulation compositions aligned with official specifications and literature values.
  • Gelatin type B (approx. 300 bloom) and 11-μm microspheres were identified.
  • Controlled in vitro release with minimal initial burst, low residual moisture (<0.5%), and methylene chloride (<1 ppm) was observed.

Conclusions:

  • The rigorous reverse engineering approach successfully characterized LD.
  • This methodology can guide the development of generic leuprolide-PLGA microspheres.
  • The findings support the feasibility of developing generic long-acting injectable formulations.