Development of 3D-printed subcutaneous implants using concentrated polymer/drug solutions

Area of Science:

• Materials Science
• Pharmaceutical Technology
• Biomedical Engineering

Background:

• Implantable drug-eluting devices offer extended therapeutic cover, reducing patient pill burden for chronic conditions.
• 3D printing enables the creation of highly tuneable, personalized drug delivery systems.

Purpose of the Study:

• To formulate subcutaneous implants loaded with olanzapine (OLZ) using robocasting, a 3D-printing technique.
• To evaluate the physicochemical properties and in vitro drug release of these implants.

Main Methods:

• Robocasting 3D-printing was used to fabricate cylindrical implants from OLZ blended with poly(caprolactone) (PCL) or PCL/poly(ethylene)glycol (PEG).
• Characterization involved scanning electron microscopy (SEM), thermal analysis, infrared spectroscopy, and X-ray diffraction.
• In vitro drug release studies were conducted over 200 days.

Main Results:

• The crystallinity of OLZ within the formulated implants was confirmed.
• All formulations exhibited sustained drug release over the 200-day study period.
• A maximum of approximately 60% drug release was observed within 200 days.

Conclusions:

• 3D-printed subcutaneous implants using robocasting are a viable method for sustained delivery of hydrophobic drugs like olanzapine.
• These implants demonstrate potential for long-term, personalized treatment of chronic conditions, minimizing frequent administration.
• The PCL and PCL/PEG formulations successfully achieved sustained release profiles over an extended period.