In the JournalsPerspective

Gel eye drops containing hrDecorin reduce corneal scarring from keratitis

Researchers have shown that a novel eye drop can be used as a method of sustained delivery of antifibrotic drugs in patients with fibrosis associated with bacterial keratitis, according to a study published in npj Regenerative Medicine.

“We believe that this drug delivery system is an ideal noninvasive antifibrotic treatment for patients with microbial keratitis, potentially without recourse to surgery, saving the sight of many in the developing world, where corneal transplantation may not be available,” the authors wrote.

Researchers aimed to test the efficacy of a fluid gel to deliver human recombinant Decorin to the ocular surface with the aim of reducing corneal opacity and scarring postbacterial keratitis.

Using a population of anaesthetized mice (n=6), researchers introduced Pseudomonas aeruginosa to infect the surface of the damaged corneas. After a 12-hour incubation, the eyes were sterilized of infection and 2 days later were administered single 5 µl gellan eye drops every 4 hours between 8:00 a.m. and 8:00 p.m. for 13 days.

Three types of gellan drop were administered among three randomized treatment groups: the first received gentamicin and prednisolone; the second received gentamicin, prednisolone and fluid gel; and the third group received gentamicin, prednisolone and hrDecorin fluid gel.

Researchers found that the fluid gel eye drops caused a reduced level of corneal opacity and scarring after 7 and 10 days of treatment. Of the three treatment groups, eyes administered the hrDecorin fluid gel showed significantly less corneal scarring.

“The structured or ‘fluid gel’ formed from gellan provides a pivotal advance since it enables the sustained delivery of molecules such as hrDecorin capable of preventing scarring and obviating the need for invasive surgical repair strategies,” the authors wrote. “The major advantage of the gellan fluid gel is its capacity to transition between solid and liquid states as it passes through the applicator and solidifies on the surface of the cornea.”

Researchers concluded that either the gel eye drop allowed the hrDecorin stay in contact with the eye long enough to reduce scarring or it altered the structure of the gel itself, creating an improved type of therapeutic bandage.

The researchers said, “Not only do the material properties of the eye drop enhance anti-scarring drug retention times, but the user-friendly nature of the drops would be welcomed by patients, providing a simple treatment to prevent the scarring pathology that is prevalent after corneal infection.” – by Scott Buzby


Disclosure: The authors report no relevant financial disclosures.

Researchers have shown that a novel eye drop can be used as a method of sustained delivery of antifibrotic drugs in patients with fibrosis associated with bacterial keratitis, according to a study published in npj Regenerative Medicine.

“We believe that this drug delivery system is an ideal noninvasive antifibrotic treatment for patients with microbial keratitis, potentially without recourse to surgery, saving the sight of many in the developing world, where corneal transplantation may not be available,” the authors wrote.

Researchers aimed to test the efficacy of a fluid gel to deliver human recombinant Decorin to the ocular surface with the aim of reducing corneal opacity and scarring postbacterial keratitis.

Using a population of anaesthetized mice (n=6), researchers introduced Pseudomonas aeruginosa to infect the surface of the damaged corneas. After a 12-hour incubation, the eyes were sterilized of infection and 2 days later were administered single 5 µl gellan eye drops every 4 hours between 8:00 a.m. and 8:00 p.m. for 13 days.

Three types of gellan drop were administered among three randomized treatment groups: the first received gentamicin and prednisolone; the second received gentamicin, prednisolone and fluid gel; and the third group received gentamicin, prednisolone and hrDecorin fluid gel.

Researchers found that the fluid gel eye drops caused a reduced level of corneal opacity and scarring after 7 and 10 days of treatment. Of the three treatment groups, eyes administered the hrDecorin fluid gel showed significantly less corneal scarring.

“The structured or ‘fluid gel’ formed from gellan provides a pivotal advance since it enables the sustained delivery of molecules such as hrDecorin capable of preventing scarring and obviating the need for invasive surgical repair strategies,” the authors wrote. “The major advantage of the gellan fluid gel is its capacity to transition between solid and liquid states as it passes through the applicator and solidifies on the surface of the cornea.”

Researchers concluded that either the gel eye drop allowed the hrDecorin stay in contact with the eye long enough to reduce scarring or it altered the structure of the gel itself, creating an improved type of therapeutic bandage.

The researchers said, “Not only do the material properties of the eye drop enhance anti-scarring drug retention times, but the user-friendly nature of the drops would be welcomed by patients, providing a simple treatment to prevent the scarring pathology that is prevalent after corneal infection.” – by Scott Buzby


Disclosure: The authors report no relevant financial disclosures.

    Perspective
    Jeffrey Varanelli

    Jeffrey Varanelli

    Corneal scarring, which affects an estimated 27.9 million people globally, is a leading cause of blindness according to the World Health Organization (Oliva et al.). Currently, the only curative treatment of an existing opacity is a corneal transplant. Attempts have been made with limited success to develop anti-scarring therapies. The shortfalls to these treatments revolve around the drop formulations and their retention on the ocular surface.

    The authors of the study discuss a novel eye drop formulation that will allow a sustained delivery of decorin, a noted anti-scarring agent. This new formulation transitions between a solid and liquid state, which increases retention time on the ocular surface, ultimately increasing both bio-efficiency and therapeutic response to topical therapies. Hill and colleagues theorize that this drug delivery system creates a noninvasive, antifibrotic treatment that could potentially save the sight of many in the developing world where the risk of corneal scarring secondary to corneal infections is significant.

    Reference:

    Oliva MS, et al. Indian J Ophthalmol. 2012;doi:10.4103/0301-4738.100540.

    • Jeffrey Varanelli, OD, FAAO
    • Simone Eye Center
      Chair, Anterior Segment Section, American Academy of Optometry

    Disclosures: Varanelli reports he has received honoraria or support from: Allergan, Bio-Tissue, Blythe Medical, Johnson & Johnson Vision Care, Katena and Shire.