Newer drug delivery systems

1. Newer Drug
Delivery Systems (NDDS)
Dr. Ashutosh Tiwari
M.D. Pharmacology
Ist Yr. Stud. SAIMS
28/11/2013

2. Drug Delivery Systems
Oral
Inject-
able Mucosal
Trans-
dermal
Ocular
Vaginal/
Anal
Needle
Needle-
less
Nasal
Buccal
Pulmonary
Active
Passive
Topical

3. Demerits of conventional dosage
forms
1. Large amount of drug is delivered to the
site
2. Therapeutic conc. is not maintained
3. Repeated dosage is necessary
4. Less patient compliance
5. Fluctations in concentration of drug in
blood

4. Definition : NDDS
Therapeutic systems that incorporate
drugs in a dosage form that releases
the medication
at a predetermined site
at a predetermined rate
over an extended period of time
from a single application

5. 1. Delivery of the drug
a) controlled rate
b) slow delivery
c) targetted delivery
2. Longer duration of action
3. ↑ bioavailability
4. ↓ Adverse Effects
5. ↑ compliance
ADVANTAGES

6. Types
• Prolonged release
–Oral preparations
–Parenteral preparations
• Targeted delivery systems
• Local delivery systems

7. Prolonged release
Oral preparations

8. Prodrugs
Inactive form of the drug which
undergoes biotransformation inside the
body to pharmacologically active drug
They increase
Absorption
Distribution
Duration of action

9. PRODRUG
Overcome
1) Pharmaceutical barrier
Chloramphenicol palmitate
2) Pharmacokinetic barrier
L-Dopa
3)Increase bioavailability
Esterification of Ampicillin
4)Increase solubilty
Esterification of vidarabine

10. ENTERIC COATED TABLETS &
CAPSULES
a) Drug coated with acid resistant substance
1. Prevent gastric irritation
2. Prevent alteration of drug in the stomach
3. To get desired conc. of drug in small
intestine
4. Retards rate of absorption and prolongs
duration of action
b) Drug coated with azopolymers for drug
delivery to colon

11. ENTERIC COATED
TABLETS &
CAPSULES

12. CONTROLLED RELEASE /
EXTENDED RELEASE / SUSTAINED
RELEASE PREPARATIONS
Release medication in a predetermined manner over
extended period of time
1. Medicines incorporated in different layers –
release drug at different time interval
OR
2. Granules of the drug can have different coatings
that dissolve at different time intervals
OR
3. Medication can be covered with a gel which can
swell and act like a semipermeable membrane

13. Granules of the drug can have
different coatings that dissolve at
different time intervals
v
v vv
v

14. Medication can be covered with
a gel which can swell and act like
a semipermeable membrane

15. ADVANTAGES
1. Therapeutic effect for longer time
2. Less fluctuation
3. ↓ frequency of drug administration
4. ↓ intensity / incidence of adverse effects

16. Prolonged Release
Parenteral preparations

17. • Pumps
–Osmotic pumps
–Portable pumps
–Computerised pumps
–Implantable pumps
• Pens
• Pellets
• Transdermal delivery system

18. PUMPS
• They deliver drugs at a predetermined rate
for a specific period following a single
application.

19. MECHANICAL PUMPS
• Insulin infusion devices:
-CSII-Continuous subcutaneous
insulin infusion device
Advantages:
• More physiological & better control
• Less variations in absorption

20. CSII-
Continuous
Subcutaneous Insulin
Infusion device
Insulin reservoir
Program chip
Keypad
Display screen

21. Patient controlled
analgesia
Infusion pump
- I/V
- Epidural
Patient can control the infusion rate
and provide the degree of pain
control

22. PCA

23. Insulin jet
Delivers insulin subcutaneously without using
needle.
Achieved by pressurizing the liquid through a
small orifice which creates high speed jet
that can penetrate the skin and underlying
tissue.

24. Dermojet
It is a sub-cutaneous
needleless injection used
for mass inoculation

25. Pellet implantation
• Drug as a solid
pellet is
implanted under
the skin to
provide uniform
systemic effect.
• Eg: testosterone

26. Pens

27. Inhalational / Pulmonary Drug delivery
system
• Inspiration through the
nose or mouth
• Alveolar epithelium
offers good surface
area especially for
lipid -soluble drugs
• The drugs are also
excreted by this route

28. 28
Metered dose inhaler
Dry powder inhalers

29. IMPLANTS
Drugs placed in pellets / capsules implanted in
body
Eg: Norplant-Contraceptive implant
Levonorgesterel  5 yrs subcutaneously

30. TRANSDERMAL THERAPEUTIC SYSTEM
or
TRANSDERMAL DRUG DELIVERY
SYSTEM

31. Transderm-SCOP
(Scoplamine)
Used for motion
sickness
Hydrogel transdermal patch:
Used in treatment of burns

32. Skin – Site of administration of systemically active drug
Advantages:
1) Avoid hepatic 1st
pass metabolism
2) Maintains constant blood level for longer period
without fluctuation
3) Improves bioavailability
4) ↓ dose to be administered and ↓ side effects
5) ↓ GI effects
6) Easy to discontinue in case of toxicity
7) ↑ patient compliance
Non invasive method

33. Transdermal patch
Scopolamine : Motion sickness
Lasts 72hr, Applied 4hrs before journey
Oral dose - action : 4-6hrs
Nitroglycerine : Angina – 1d
Clonidine : Hypertension – 7d
Nicotine : Smokers - 1 d
Fentanyl : Pain - 3 d

34. Local controlled
delivery systems

35. OCULAR SYSTEMS
Ocusert:
Eg: Pilocarpine ocusert
- Treatment of glaucoma
Lasts 7 days
Less side effects
Dose also ↓

36. VAGINAL & UTERINE SYSTEMS
Progestasert:
Hormone releasing IUCD
Release 60µg/d of progesterone for 1 year
Dinoprostone vaginal insert:
Inserted vaginally
Absorbs water swells and release drug
- cervical ripening

37. IONTOPHORESIS

38. IONTOPHORESIS
Mild electric current applied for the transport of
drug across the skin
Eg: Vasopressin, Dexamethasone

39. Drug eluting stents:
Stents can be coated with drugs
embedded in a surface polymer

40. Targeted drug delivery
systems

41. LIPOSOMES
Bilayered vesicles made of amphipathic
phospholipids
E g: Liposomal Amphotericin B

43. Monoclonal antibodies
• mAbs act directly
when binding to a
cancer specific antigen
and induce
immunological
response to cancer
cells
• mAbs were modified
for delivery of a toxin,
cytokine or other
active conjugates
monospecific antibodies that are the
same because they are made by identical
immune cells that are all clones of a
unique parent cell, Monoclonal
antibodies have monovalent affinity, in
that they bind to the same epitope.

44. Future Opportunities
•Gene Therapy
•Nanoparticles

46. Nanoparticle based drug delivery
Using nanotechnology the drug can be targeted to
a precise location which would make the drug
much more effective & reduce the chances of
possible side-effects
•More specific drug targeting & delivery
•Reduction in toxicity while maintaining
therapeutic efficiency
•Nanocarriers-
Nanoparticles,Nanotubule,Nanoshell
46

47. Carbon Nanotubules
Used in treatment of
Bronchial asthma
Gold Nanoparticles
Cancer chemotherapy
-free radical generation

48. Nanoerythrosomes
Nanoerythrosomes are resealed erythrocytes that can carry
proteins ,enzymes & macromolecules.They are used in the
treatment of liver tumor,parasitic disease & enzyme disease

49. Dendrimer Modified Buckyball
They deliver radioactive atoms to cancerous
material.Eg:C-60 against CA colon
Transfer of radiation is within the ball hence
minimise strong radiation to healthy tissue
Dendrimer-highly branched
globular
Biodegradable synthetic
molecule.

50. 10/20/2012 50
Thank You