Biodegradable scleral implants as new triamcinolone acetonide delivery systems

Area of Science:

• Ophthalmology
• Biomaterials Science
• Drug Delivery Systems

Background:

• Ocular drug delivery faces challenges with frequent administration and limited bioavailability.
• Sustained release of anti-inflammatory drugs like triamcinolone acetonide (TA) is crucial for managing various eye conditions.

Purpose of the Study:

• To develop novel ocular scleral implants for long-term release of triamcinolone acetonide (TA).
• To evaluate the biocompatibility and drug release profile of these implants in vivo.

Main Methods:

• Scleral discs were fabricated using compression-molding with poly(methylidene malonate) (PMM2.1.2) as the polymer matrix.
• High molecular weight PMM2.1.2 (100,000-150,000 Da) was combined with plasticizers (ethoxylated stearic acid or methylidene malonate oligomers).
• Implants were tested for mechanical properties, ocular biocompatibility, and TA release in rabbit eyes.

Main Results:

• The developed scleral implants exhibited suitable mechanical properties for ocular implantation.
• In vivo studies in rabbit eyes demonstrated excellent ocular biocompatibility with no significant inflammation.
• Implants successfully released therapeutically relevant concentrations of TA into the vitreous and sclera for up to 5 weeks.

Conclusions:

• Poly(methylidene malonate) (PMM2.1.2)-based scleral implants are a promising platform for sustained ocular drug delivery.
• These implants offer good biocompatibility and controlled release of triamcinolone acetonide, potentially reducing the need for frequent injections.