Self-Plugging Microneedle (SPM) for Intravitreal Drug Delivery

Area of Science:

• Ophthalmology
• Biomaterials Science
• Drug Delivery Systems

Background:

• Intravitreal injection (IVI) is a standard method for treating eye diseases, but carries risks like ocular tissue damage and infection from needle retraction.
• Current IVI methods often require repeated injections, increasing potential complications and patient discomfort.
• Microneedles (MNs) have shown promise for ocular drug delivery with a good safety profile, but lack a self-sealing mechanism.

Purpose of the Study:

• To develop and evaluate a self-plugging microneedle (SPM) for single-time intraocular drug delivery.
• To simultaneously seal the scleral puncture after drug delivery, preventing leakage and infection.
• To assess the safety and efficacy of SPMs for sustained drug delivery in an ocular model.

Main Methods:

• SPMs were fabricated using a thermal drawing process.
• Microneedles were coated with a drug-loaded polymeric carrier and a hydrogel-based scleral plugging component.
• In vitro, ex vivo, and in vivo studies (porcine model) were conducted to characterize functional layers and evaluate performance.

Main Results:

• Fabricated SPMs demonstrated successful drug loading and hydrogel component integration.
• In vitro and ex vivo tests confirmed the functional integrity and sealing capabilities of the SPMs.
• In vivo porcine model tests showed prompt sealing of the scleral puncture and sustained intraocular drug delivery.

Conclusions:

• The developed self-plugging microneedle (SPM) technology provides a promising approach for safer and more effective intraocular drug delivery.
• SPMs offer a single-injection solution that minimizes risks associated with traditional intravitreal injections.
• This technology has the potential to improve patient outcomes and reduce complications in ophthalmic treatments.