INTRODUCTION
Corneal injury is a common disease which is accounting for approximately
3% of emergency department visits. [1] Cornea can be injured from
numerous causes including oculopathy, mechanical trauma, infection,
inflammation, chemicals, and radiation. [2] Corneal injury is
important because it may be vision-threatening. However, there are no
absolute medical therapies for it.
Corneal healing consists of a complex process involving cell death,
migration, proliferation, differentiation, and extracellular matrix
remodeling. [3] In addition, limbal stem cells and basement membrane
remodeling have key roles in corneal healing. [4] Numerous
cytokines, chemokines, and growth factors are involved in corneal
healing.
Epidermal growth factor (EGF) is one of the growth factors which is
secreted from lacrimal gland. [5] EGF involves corneal healing; it
regenerates limbal stem cells and regulates migration of corneal cells
thus accelerating corneal healing. [6, 7] In addition, previous
studies showed that tear EGF concentration was significantly decreased
in dry eye syndrome which is the one of common causes of corneal injury.
[8] Therefore, EGF has been thought a treatment option for corneal
injury.
For the treatment of corneal injury, the topical eye administration of
EGF has been used through cord blood serum, autologous serum, amniotic
membrane extract, and amniotic membrane transplantation. [9-12]
However, the currently implemented treatment options may not be wildly
used because these mass produce for treatment options is difficult, not
only infection risk is relatively high. Therefore, human recombinant EGF
(rhEGF) eyedrops can be an appropriate treatment option to solve the
above problems.
Some studies showed the effect of rhEGF eyedrops in vitro study and
animal study. [7, 13] However, there are no published human data
about rhEGF eyedrops. The purpose of this study was to evaluate the
safety/tolerability, and pharmacokinetics (PKs) of EGF in serum and tear
after topical administration of a single and multiple doses of rhEGF
eyedrops in healthy subjects.