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A Package of Established Analytical Tools to Investigate the Solid-State Alteration of Lipid-Based Excipients
Published on: August 9, 2022
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Long-term release and stability of pharmaceutical proteins delivered from solid lipid implants
Moritz Vollrath1, Julia Engert1, Gerhard Winter1
1Department of Pharmacy, Pharmaceutical Technology and Biopharmaceutics, Ludwig-Maximilians-University, Butenandtstrasse 5-13, Munich D-81377, Germany.
Summary
Solid lipid implants (SLIs) offer sustained protein release for 120 days. This study evaluated monoclonal antibody and Ranibizumab stability, showing SLIs are promising for long-term drug delivery.
Area of Science:
- Pharmaceutical Technology
- Biomaterials Science
- Drug Delivery Systems
Background:
- Solid lipid implants (SLIs) are a promising platform for sustained pharmaceutical protein delivery.
- Twin-screw (TSC) extrusion is an effective method for preparing SLIs.
Purpose of the Study:
- To evaluate the long-term release and stability of proteins incorporated into SLIs prepared by TSC extrusion.
- To assess the impact of protein loading on release profiles and protein integrity.
Main Methods:
- SLIs were fabricated using TSC extrusion with specific triglycerides (H12 and Dynasan D118).
- Two proteins, a monoclonal antibody (mAb) and Ranibizumab, were incorporated into a hydroxypropyl-β-cyclodextrine (HP-β-CD) matrix.
- Protein release and stability were analyzed using various chromatography (SE-HPLC, IEX, HIC) and electrophoresis (SDS-PAGE) techniques, alongside FT-IR spectroscopy.
Main Results:
- Sustained release of both proteins was observed for approximately 120 days.
- Increased protein load up to 3.00 mg per implant did not affect release profiles.
- The monoclonal antibody showed some degradation (7% monomer loss, 16% acidic subspecies), while Ranibizumab remained largely intact (>95% monomeric).
Conclusions:
- SLIs prepared by TSC extrusion demonstrate potential for long-term sustained release of pharmaceutical proteins.
- The stability of released proteins varies, with Ranibizumab showing higher stability than the monoclonal antibody under tested conditions.
- SLIs are a viable platform for applications requiring prolonged drug delivery, such as intraocular delivery for age-related macular degeneration (AMD).
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