ocular drug delivery system

1. Presented by : Mr. Ankur
M Pharm.1st sem
(1394011)
Kuk (IPS)
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2.  Introduction
 Anatomy of eye
 Mechanism of drug absorption
 Factors affecting bioavailability
 Barriers
 Classification of ODDS
 Inserts
 Challenges and researches
 References
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3.  Ocular administration of drug is primarily
associated with the need to treat ophthalmic diseases.
 Eye is the most easily accessible site for topical
administration of a medication.
 Ideal ophthalmic drug delivery must be able to
sustain the drug release and to remain in the contact
of the eye for prolong period of time.
 The unique structure of the eye restricts the entry
of drug molecules at the required site of action
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5.  The eye is composed of two components:
 Anterior segment: consists of front one-third of eye that mainly includes pupil,
cornea, iris, ciliary body, aqueous humor, and lens.
 Posterior segment: consists of the back two-thirds of the eye that includes
vitreous humor, retina, choroid, macula, and optic nerve.
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6. ADVANTAGES:-
 Increase ocular residence,
hence improving
bioavailability.
 Possibility of providing a
prolonged drug release and
thus a better efficacy
 . Increased shelf life with
respect to aqueous solutions.
 Exclusion of preservatives,
thus reducing the risk of
sensitivity reactions as
compare to aqueous solutions.
DISADVANTAGES:-
 It is Expensive.
 Insertion technique is
difficult & expulsion of shields
may occur not individually fit
for each patient.
 Shields are not fully
transparent & thus reduce
visual activity.
 Occasional inadvertent loss.
 Difficult to handle.
 Foreign body sensation.
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7.  Good corneal penetration.
 Prolong contact time with corneal tissue.
 Simplicity of instillation for the patient
 . Non irritative and comfortable form.
 Appropriate rheological properties.
 Inert and stable.
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8. Non- corneal absorption:
Penetration across sclera & conjunctiva into intra ocular
tissues.
Non productive: because penetrated drug is absorbed by
general circulation.
Corneal absorption:
Outer epithelium: rate limiting barrier, with pore size 60a,
only access to small ionic and lipophilic molecules.
Trans cellular transport: transport between corneal
epithelium and stroma.
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10. 1. Inflow & outflow of lacrimal fluids.
2. Efficient naso-lacrimal drainage.
3. Interaction of drug with proteins of lacrimal
fluid.
4. dilution with tears.
5. Corneal barriers.
6. Active ion transport at cornea.
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12. OCULAR DELIVERY
SYSTEMS
CONVENTIONAL VESICULAR
CONTROL
RELEASE
PARTICULATE
IMPLANTS
HYDROGELS
DENDRIMERS
IONTOPORESIS
COLLAGEN SHIELD
POLYMERIC
SOLUTIONS
CONTACT LENSES
CYCLODEXRIN
MICROONEEDLE
MICROEMULSIONS
NANO SUSPENSION
ADVANCED
SCLERAL PLUGS
GENE DELIVERY
Si RNA
STEM CELL
ECT
MICROPARTICLE
S
NANOPARTICLES
LIPOSOMES
NIOSOMES
DISCOMES
PHARMACOSOME
S
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13.  Ocular insert (Ocusert) are sterile preparation that prolong
residence time of drug with a controlled release manner and
negligible or less affected by nasolacrimal damage.
 Inserts are available in different varieties depending upon their
composition and applications.
 Lacrisert is a sterile rod shaped device for the treatment of dry eye
syndrome and keratitis sicca.
They act by imbibing water from the cornea and conjunctiva and
form a hydrophilic film which lubricates the cornea.
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14. CLASSIFICATION :
1 .NON ERODIBLE INSERTS
i. Ocusert
ii. Contact lens
2 .ERODIBLE INSERTS
i. Lacriserts
ii. SODI
iii. Mindisc
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15. OCUSERT:
 The Ocusert therapeutic system is a flat, flexible, elliptical device
designed to be placed in the inferior cul-de-sac between the sclera and
the eyelid and to release Pilocarpine continuously at a steady rate for 7
days.
The device consists of 3 layers…..
1. Outer layer - ethylene vinyl acetate copolymer layer.
2. Inner Core - Pilocarpine gelled with alginate main polymer.
3. A retaining ring - of EVA impregnated with titanium di oxide
(diagram)
The ocuserts available in two forms.
Pilo - 20 :- 20 microgram/hour
Pilo – 40 :-40 micrograms/hour
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16. ADVANTAGES:
Reduced local side effects and toxicity.
Easily administered by patient
Improved compliance.
DISADVANTAGES:
Retention in the eye for the full 7 days.
Periodical check of unit.
Replacement of contaminated unit
Expensive.
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17. The solid inserts absorb the aqueous tear fluid and gradually
erode or disintegrate. The drug is slowly leached from the
hydrophilic matrix.
they quickly lose their solid integrity and are squeezed out of
the eye with eye movement and blinking.
do not have to be removed at the end of their use.
Three types :
1. LACRISERTS
2. SODI
3. MINIDISC
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18. LACRISERTS:
Sterile rod shaped device made up of hydroxyl
propyl cellulose without any preservative.
For the treatment of dry eye syndromes
It weighs 5 mg and measures 1.27 mm in
diameter with a length of 3.5 mm.
It is inserted into the inferior fornix.
SODI:
Soluble ocular drug inserts
Small oval wafer
Sterile thin film of oval shape
Weighs 15-16 mg
Use – glaucoma
Advantage – Single application
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19. MINIDISC:
Countered disc with a convex front and a concave
back surface
Diameter – 4 to 5 mm
Composition:
Silicone based prepolymer-alpha-w-dis (4-
methacryloxy)-butyl poly di methyl siloxane.
(M2DX)
M-Methyl a cryloxy butyl functionalities.
D – Di methyl siloxane functionalities.
Pilocarpine, chloramphenicol
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20. Registered
name
Active
substances
Implant size Marketing
status
References
vitrasert® Ganciclovir Millimeter Clinical use www.bausch.co
m
retisert® Flucinolone
acetonide
Tablet 3mmx
2mmx
5mm
Clinical use www.bausch.co
m
Medidur Flucinolone
acetonide
Cylindrical tube
3.5
mm in length
and
0.37 mm in
diameter
Phase 3 www.psivida.co
m
Posurdex Dexamethasone Microsized
implant
Phase 3 www.retinalphy
sician.com
Ozurdex® Dexamethasone intravitreal
implant)
0.7 mg
Clinical use www.allergan.c
om
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21.  HAEMATIC DERIVATIVES
 Jesús Merayo MD from Spain opened the symposium with a presentation on the potential of haematic
derivatives to treat a wide range of ocular surface diseases. He explained that platelet-rich plasma
(PRP) derivates work by supplying fundamental factors to maintain the integrity of the ocular surface.
Current PRP preparation methods are highly variable and yield a range of products including plasma
rich in growth factors (PRGF), which is particularly interesting for ophthalmic applications.
Nanoparticles:
 Turning to the rich potential of nanomaterials to deliver effective drug delivery to ocular tissues,
Quirina Ferreira MD from Portugal shared her research on a novel combination approach to treating
glaucoma.
 This is focused on the possibility of using nanostructured films as a delivery vehicle for brimonidine to
treat glaucoma.
 “The layer-by-layer films are able to release precise amounts of brimonidine to the biological
environment at specific periods of time. In addition to glaucoma, these nanostructured films may be
used with other ocular drugs and can be coated in any type of surface or ocular device,” she said. In
vitro and in vivo trials are needed to validate the films’ efficiency in the ocular environment
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22.  www.eurotimes.org/challenges-innovations-ocular-drug-
delivery-methods
 https://en.wikipedia.org/wiki/Main_Page
 • Lachman/Lieberman’s “The Theory and Practice Of Industrial
Pharmacy” Fourth Edition 2013, Edited by: Roop K Khar, SP Vyas,
Farhan J Ahmad, Gaurav K Jain, CBS Publishers and Distributors Pvt
Ltd, New Delhi
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