Bioadhesive ophthalmic drug insert

What are the conventional ophthalmic preparation ?

Drops

(suspensions ,solutions)

ointments

What are the non conventional types(alternative approaches)?

Ocular iontophoresisDrug-

presoaked hydrogel type contact Lens.

Artificial tear

inserts.

Collagen shields

or corneal shields.

Ocular inserts.

Phase transition systems.Microspheres and nanoparticles

Q/ what are the problem with the conventional ophthalmic dosage form? That lead to the innovation of ocular inserts

Problems: 1. rapid precorneal drug loss due to nasolacrimal

drainage2. tear turnover and drug dilution resulting in

poor bioavailability3. binding of the lacrimal proteins 4. limited corneal area and poor corneal

permeability5. nonproductive absorption /adsorption6. Pulsed dosing of drug.

Way this problem is a lot in this type of dosage forms?

• The anatomy, physiology and biochemistry of the eye render this organ exquisitely impervious to foreign substances.SO The introduction of ophthalmic insert solves many problems present with conventional ocular dosage forms

So we should concentrate on two things: 1) To prolong the contact time 2) To enhance corneal permeability either by mild or transient structural alteration of corneal epithelium or by modification of chemical structure of the drug molecules.

Define “Bioadhesive” and by which intervention we can obtain Bioadhesive

properties? • Bioadhesive can be defined as a state in which

two components, of which one is of biological origin, are held together for extended periods by the help of interfacial forces. In case of bioadhesive drug delivery, the term bioadhesion is used to describe the adhesion between polymers, either synthetic or natural and soft tissues.

• So by the use of certain polymer matrix we can get bioadhesion

Bioadhesive

what are the Bioadhesive ophthalmic drug inserts(BODI) ?

BODIs are soluble type of “ocular insert” .Ocular inserts: are -sterile, -thin, mono or multilayered, -drug-impregnated or not, -solid or semisolid devices placed into the cul-de-sac or conjuctival sac, whose size and shape are especially designed for ophthalmic application. “They are composed of a polymeric support that may or may not contain a drug.”

Bioadhesive ophthalmic drug inserts

Soluble adhesive

rods ocular insert

What are the advantage of BODI over the other types of conventional ocular insert?

• overcome the main problems with conventional ophthalmic inserts, which include their site of application and the risk of expulsion from the site.

• BODI are totally eliminated • do not need to be removed, • thus limiting manipulations to insertion only.

what are the Criteria for Successful Ocular Inserts?

• Comfort and noninterference with vision • Biocompatibility and stability • Reproducibility of release kinetics • Applicability to a variety of drugs • Ease of sterility and nontoxicity • Ease of handling ( insertion and removal) • Ease of manufacture and low cost.

What are the advantage of ocular insert ?

• Increased contact time • prolonged drug release • Reduction in dosage frequency • an accurate dose • Reduction of systemic side effect . • Reproducibility of release kinetics. • Sterility. • Increased shelf life with comparison to aqueous

solutions due to absence of water.

So what are the disadvantages?

• Perceived by the patient as a foreign body.• Movement around the eye.( not the case with

BODI) • Occasionally lose during sleep or while

rubbing eyes• Interference with vision• Difficulty in placement and removal ( BODI

need no removal )

what are the considerations of manufacturing?

• 1. Thickness of Insert• 2. Surface pH determination• 3. Mechanical strength• 4. Bioadhesive strength• 5. Sterility • 6. Pattern and rate of the release of drug and

accuracy of the dose• 7. Dissolution rate • 8. Type of the polymer used and its swelling factor

What are the Components Of Soluble Inserts?

Drug polymer Additives

Soluble synthetic polymers

Cellulose derivatives – Hydroxypropyl cellulose methylcellulose, hydroxyethyl cellulose and hydroxypropyl cellulose. Divers – Polyvinyl alcohol, ethylene vinyl acetate copolymer.

Additives Plastisizer – Polyethylene glycol, glycerin, propylene glycol Enteric coated polymer – Cellulose acetate phthalate, hydroxypropyl methylcellulose phthalate. Complexing agent – Polyvinyl pyrrolidone. Bioadhesives – Polyacrylic acids

By which methods preparation is happen?

Various methods used in preparation. Examples: 1. Solvent casting method2. Glass substrate technique3. Melt extrusion technique

Solvent casting method

Polymer D.WDissolved polymer plastici

zer

DRUG

Poured in glass petridish Evaporation

dried films thus obtained

Solvent casting method• using different ratios of drug and polymer • The polymer is dissolved in distilled water. • A plasticizer is added under stirring conditions. • The weighed amount of drug was added • the casting solution was poured in clean glass

petridish and covered with an inverted funnel to allow slow and uniform evaporation at room temperature for 48 h.

• The dried films thus obtained • The ocular inserts were then stored in an airtight

container (desiccator) under ambient condition

examples of drugs that can be incorporated in the BODI ?

acyclovir chitosan gatifloxacin levofloxacin natamycin ofloxacin phenylephrine

diclofenac sodium idoxuridine norfloxacin pefloxacin timolol maleate brimodine and pilocarpine

CONCLUSION

• BODI are sterile polymeric drug• Soluble type of ocular insert • Have many advantage the most important is

increase contact time and controlled release• prepared by polymerization technique• Applicable with many drugs