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@ U S T . H K
People with diseases that require
frequent injections into their eyeballs
have been given hope that the ocular
medicines they need can be delivered
without pain andmuch less frequently.
Prof Ying Chau leads research in
biomaterials for drug delivery, specializing
in the ocular area. Her research teams
have come up with two breakthroughs
for delivering ophthalmic drugs to the
eye, which they hope will improve the
treatment of increasingly common
diseases such as age-related macular
degeneration and diabetic retinopathy.
Both have now been patented through
the University’s Technology Transfer
Center, in preparation for downstream
start-up development, led by the students
involved in the initial studies.
The first invention has been pioneered
by Prof Chau’s team since 2006 and is
now being championed by Dr Langston
Suen, who was trained in her lab.
This uses ultrasound to non-invasively
VISIBLE DIFFERENCE
deliver drugs to the back of the eye to
treat retinal diseases, replacing injections
into the eyeball that are often painful,
leave wounds, and come with the risk
of infection, among other side effects.
Ultrasound, the team discovered, provides
physical energy that temporarily disrupts
natural ocular barriers, opening the
door for drug treatment. The innovation
won the Institution of Engineering and
Technology Healthcare Technologies
Innovation Award in the UK in 2016,
among other prizes, and is now poised to
compete in a global drugs market worth
nearly US$10 billion for the treatment
of retinal diseases according to the
Controlled Release Society, a premier
organization worldwide for delivery
science and technology.
The second breakthrough, derived
from studies led by Dr Yu Yu, a
postdoctoral research fellow in Prof
Chau’s team, employs a new injectable
hydrogel biomaterial. The ocular drug is
Age-related macular degeneration
Diabetic retinopathy
A novel hydrogel-based drug
carrier can maintain the drug’s
therapeutic effect in the eye for
a long period of time, reducing
the need for regular treatment
by injection.
Drug-loaded
hydrogel biomaterial
An ultrasound applicator with
low frequency range enhances the
transport of macromolecules across
the sclera
(
tough white part of the
eye
)
, thus allowing the ocular drug
to permeate into the eye.
Non-invasive
ultrasound technology
wrapped in the gel to allow its slow
release, thus extending the time
between treatments for eye diseases to
at least six months, compared with
monthly injection required by traditional
treatment.
The hydrogel makes use of natural
hyaluronic acid (HA), which is similar
to the vitreous, a gel found in the eye,
with additional properties engineered
to control the speed of degradation.
“We started with HA and modified it to
become an injectable gel. The chemistry
and formulation are focused on
extremely slow release,” said Prof Chau.
The hydrogel has excellent
compatibility with the eye based on
preclinical testing. It can also improve
treatment of front-of-eye problems, such
as dry eye and cornea wounds, and can
be applicable for human and veterinary
use. Its use for treating dry eye in dogs
is already being evaluated together with
a local veterinary hospital.
Hydrogel
