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Single Administration of a Biodegradable, Separable Microneedle Can Substitute for Repeated Application of Eyedrops
SeungHyun Park1, KangJu Lee2, Heekyoung Kang3,4,5
1Department of Mechanical Engineering, Yonsei University, Seoul, 03722, Republic of Korea.
Abstract:
Infectious keratitis is mainly treated with topical antibiotics. To achieve and maintain the required therapeutic concentration in the cornea where the tear fluid continuously rinses the surface, the antibiotics must be frequently applied, even while the patient is sleeping, and oral medication is sometimes required. However, the inevitably poor compliance and avascular nature of the cornea decrease drug bioavailability. In this study, a single microneedle (MN) is injected into the cornea to substitute for the repeated application of eyedrops in the treatment of infectious keratitis. After comparing the mechanical integrity and drug release profiles of three different drug-tips, the drug-tip with the "high" drug concentration that releases 12.5 ng drug within 3 days is applied to a cornea to evaluate the transferability and in vivo drug release. In the treatment of infectious keratitis with repeated application of eyedrops for six consecutive days, a single MN injection is substituted for the initial 3 days of eyedrop applications. The progression remains similarly attenuated after 3 days without eyedrops, and comparable efficacy is achieved on day 6 when combined with delayed eyedrop treatment from day 3. Thus, the single administration of a biodegradable MN can substitute for the repeated application of eyedrops in the treatment of infectious keratitis.
Insights
A single microneedle injection can replace frequent antibiotic eye drops for infectious keratitis. This novel approach improves drug delivery to the cornea, simplifying treatment and enhancing patient compliance.
Area of Science:
- Ophthalmology
- Drug Delivery
- Biomaterials
Background:
- Infectious keratitis treatment relies on topical antibiotics, demanding frequent application.
- Poor patient compliance and the cornea's avascular nature limit topical antibiotic efficacy.
- Achieving therapeutic drug concentrations in the cornea is challenging due to tear fluid washout.
Purpose of the Study:
- To evaluate a single microneedle (MN) injection as a substitute for repeated topical antibiotic eyedrops in treating infectious keratitis.
- To assess the mechanical integrity and drug release kinetics of different MN drug-tips.
- To determine the in vivo efficacy of MN-based drug delivery compared to conventional eyedrops.
Main Methods:
- Three drug-tip designs were compared for mechanical integrity and drug release profiles.
- A selected high-drug-concentration MN (releasing 12.5 ng over 3 days) was tested for corneal transferability and in vivo release.
- Infectious keratitis models were treated with a single MN injection replacing the first 3 days of eyedrops, with delayed eyedrop treatment initiated on day 3.
Main Results:
- A microneedle releasing 12.5 ng of drug over 3 days demonstrated suitable properties for corneal application.
- A single MN injection effectively substituted for the initial 3 days of eyedrop treatment.
- Disease progression was similarly attenuated, and comparable efficacy was achieved by day 6 with delayed eyedrop initiation.
Conclusions:
- A single biodegradable microneedle injection offers a viable alternative to frequent topical antibiotic eyedrops for infectious keratitis.
- This microneedle approach enhances drug bioavailability and simplifies treatment regimens.
- The study demonstrates the potential of microneedle technology for improving ocular drug delivery and patient compliance.
