Presentation on the Targeted Drug Delivery Systems. topic included by PCI to the master's course in Pharmaceutics

1. Guided by
Dr. Sayyad F. J.
(HOD, Department of Pharmaceutics)
Presented by
Somani R. M.
(M.Pharm F. Y.)
Government College of Pharmacy,
Karad

2. CONTENT
• INTRODUCTION.
• BIOLOGICAL PROCESS.
• TUMOR TARGETING.
• BRAIN SPECIFIC DELIVERY.
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3. DEFINITION
Targeted drug delivery, also known as smart drug
delivery,
It is a method of treatment that involves the increase
in drug concentration in one or few body parts in
comparison to others. Therefore, it delivers the
medication only to areas of interest within the body.
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4. PRINCIPLE REQUIREMENTS
• There are four principle requirements for a successful targeted
drug delivery system
There should be proper Loading of the drug into an appropriate
drug delivery vehicle,
It must possess an ability to Escape the body's secretions that
may degrade it,
Leading to a long Residence time in circulation and thereby
reaching the Site(Target) of interest and, should release the drug
at the specific site within the time that calls for effective drug
functioning.
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5. ADVANTAGES OF A TARGETED
DRUG DELIVERY SYSTEM
• Increased Treatment efficacy.
• Increased Specific Localization.
• Controlled Biological Distribution.
• Modulated Pharmacokinetic
• Reduced Dose.
• Improved Patience Compliance.
• Decreased Toxic Side Effects.
• Selective targeting to infections cells that compare to
normal cells.
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6. NEED OF TARGETING DRUG
DELIVERY SYSTEM
1. Pharmaceutical reason
A. Drug instability
B. Low solubility
2. Pharmacokinetic reason
A. Poor absorption
B. Short half life.
C. Large volume of distribution.
3. Pharmacodynamics reason.
A. Low specificity
B. Low therapeutic index
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7. IDEAL CHARACTERISTICS
• It should be nontoxic, biocompatible, biodegradable,
and physicochemical stable invivo and invitro.
• Restrict drug distribution to target cells or tissues or
organs and should have uniform capillary
distribution.
• Minimal drug leakage during transit.
• Carriers used must be bio-degradable or readily
eliminated from the body without any problem and
no carrier induced modulation of diseased state.
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8. WHICH TYPE OF DRUG CAN BE
GIVEN THROUGH TARGETED
DRUG DELIVERY SYSTEMS
• Drug which have affinity to very specific receptors
can be given through Targeted Drug Delivery
Systems.
• Highly potent drug.
• Drug which may cause severe adverse effect when
comes in contact with different organ system.
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9. COMPONENTS OF DRUG
TARGETING
Any drug delivery system comprises of a target and
the drug carriers or markers required for it
• Target :-Target means an organ or a tissue or a cell,
which is in need of treatment.
• Drug Carrier:- Carriers are vectors specifically
engineered for the purpose of holding a drug inside
them. This is possible by means of encapsulation. It
should be easily recognized by the target cells and
the drug-ligand complex hence formed should be
stable.
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10. 3 Types of targeting is done
Depending on site
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Type I First order targeting organ
compartmentalization
Type II Second order targeting Cellular targeting
Type III Third order targeting Intracellular targeting

11. STRATEGIES OF DRUG
TAERGETING
• Passive targeting
• Active targeting
• Physical Targeting
• Dual Targeting
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12. Passive targeting :-
• Drug delivery systems which are targeted to systemic
circulation are characterized as Passive delivery
systems.
• In this technique drug targeting occurs because of the
body’s natural response to physicochemical
characteristics of the drug or drug carrier system.
Active targeting :-
• In this approach carrier system bearing drug reaches to
specific site on the basis of modification made on its
surface rather than natural uptake by RES (Reticulo
Endothelial Systems).
• Surface modification technique include coating of surface
with either a bio adhesive, nonionic surfactant or specific
cell or tissue antibodies (i.e. monoclonal antibodies) or
by albumin protein.
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13. • Physical Targeting
In this type of targeting some characteristics of environment
changes like pH, temperature, light intensity, electric field,
ionic strength small and even specific stimuli like glucose
concentration are used to localize the drug carrier to
predetermined site.
• Dual Targeting
In this targeting approach carrier molecule itself have their
own therapeutic activity and thus increase the therapeutic
effect of drug also.
• For example, a carrier molecule having its own antiviral
activity can be loaded with antiviral drug and the net
synergistic effect of drug conjugate was observed.
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14. DEVICES USED IN TARGETING
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Sr.No Devices name Description Application
1 Nano tubes They are hollow cylinder made of
carbon, atoms which can be filled
and sealed for potential drug
delivery.
Help to identify
DNA changes
associated
with cancer cells
2 Nano shells Nano shells are hollow
silica spheres covered with gold.
It has potential for
targeting
cancerous drug.
3 Quantum dots Quantum dots are miniscule
semiconductor particles that can
serve as sign posts of certain types
of cells or molecules in the body.
This technique has
potential for
targeting
cancerous drug.
4 Dendrimers Dendrimers are new class of
macromolecules which have a
symmetric core and form the 3-D
spherical structure. These have
branching shape which gives them
vast amounts of surface area.
It useful in gene
transfection and
medical imaging.

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Tumor is a swelling of a part of the body, generally without
inflammation, caused by an abnormal growth of tissue, whether
benign or malignant.
Barriers to Tumor Targeting
• Cellular Barriers.
• Tumor Microenvironment.
• Hypoxic core and extracellular pH of tumors.
• Vesicular and organellar barriers.
To over come these barriers different Strategies and devices of
Drug Targeting specific to tumor are discussed above.
TUMOR TARGETING

16. Among different barriers in human body, Blood Brain
Barrier is a strongest barrier to cross.
There are different approaches have been utilized
successfully to promote crossing the BBB by drugs.
1. Use of permeation enhancers such as DMSO.
2. Osmotic disruption of the BBB by infusing internal
carotid artery with mannitol.
3. Use of dihydropyridine redox system as drug carrier
to brain.
4. Highly lipid soluble drugs with less molecular weight.
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BRAIN SPECIFIC DELIVERY

17. STRATEGIES FOR BRAIN DRUG DELIVERY.
• Viral vectors
• Nanoparticles
• Exosomes
• Delivery through active transporters in the BBB.
• Brain permeability enhancer
• Delivery through the permeable BBB under
disease conditions.
• Non-invasive techniques to enhance brain drug
uptake.
• Alteration of administration routes
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18. • Viral vectors :-
Viral vectors have a natural ability to infect cells with
nucleic acids. The application of viral vectors for gene
delivery to patients with neurological disorders has
been investigated for over two decades.
Lentivirus, herpes simplex virus, adenovirus and
adeno-associated virus (AAV) vectors have achieved
gene transduction in the brain.
The limitations of using viral vectors for drug delivery
include difficulties in manufacturing, high cost of
production, and, most importantly, the safety of viral
vectors.
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19. • Non-viral nanoparticles :-
It have an advantage that it help in Actively
targeted delivery; brain targeting using specific
physiological conditions is possible.
• Exosomes :-
Exosomes are small extracellular vesicles
secreted by cells. The major advantage of
exosomes versus other synthetic nanoparticles
is their non-immunogenic nature, leading to a
long and stable circulation.
Exosomes have been utilized to deliver small
molecules, proteins and nucleic acids to cross
the BBB.
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20. • Delivery of drugs through active transporters in the blood-
brain barrier :-
Endogenous amino acids enter the brain through the
transportation systems within the BBB. One attractive approach
on brain drug delivery utilizes this knowledge to link drugs with
amino acids that actively cross the BBB.
• Brain permeability enhancers :-
Many molecules have demonstrated the ability to transiently open
the BBB and allow high concentrations of systemically
administered chemotherapeutics to reach the brain.
One of the rationales for these molecules to open the BBB is
based on the transient disruption of the BBB by decreasing
expression of Tight Junction proteins such as claudin-1, occludin
and tricellulin.
Their early application was for intraarterial mannitol with
chemotherapy agents to treat brain tumors.
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21. • Delivery of drugs through the permeable blood-brain
barrier under disease conditions :-
glutamate release in ECs promotes BBB permeability.
Interendothelial junctions are key structures to maintain tissue-
fluid homeostasis in the healthy brain.
Under certain disease conditions, proteinaceous fluid enters the
interstitium through the disrupted interendothelial junctions,
consequently causing edema.
On the other hand, brain injury further alters BBB permeability in
the progression of the diseases.
• Non-invasive techniques to enhance brain drug uptake :-
Ultrasound has become an attractive technique to facilitate drugs
to cross the BBB in recent years.
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22. THANK
YOU
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23. REFERENCE
• Controlled and novel drug delivary by N.K. Jain CBS
publication.
• Recent Advances in Tumor Targeting Approaches by
Kaushik Thanki , Varun Kushwah , and Sanyog Jain.
• Targeted drug delivery- a review by e.Bhargav*, n.Madhuri,
k.Ramesh, anand manne, v.Ravi, world journal of pharmacy
and pharmaceutical sciences volume 3, issue 1, 150-169.
• Brain targeted drug delivery system: a review by parle
pallavi*, aggarwal geeta and kumar s. L. Hari world journal of
pharmacy and pharmaceutical sciences Volume 5, issue 6,
398-414.
• A Review on Targeted Drug Delivery: its Entire Focus on
Advanced Therapeutics and Diagnostics Kirti Rani*, Saurabh
Paliwal Scholars Journal of Applied Medical Sciences Sch. J.
App. Med. Sci., 2014; 2(1C):328-331
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