NANOMEDICINE & DRUG DELIVERY SYSTEMS

UNIT 1-PROSPECT OF NANOMEDICINE

BIO-PHARMACEUTICALS

Seminar byR.DELMA JONES RUFINA

II M.Tech-NST

PREAMBLE

Biopharmaceuticals are medical drugs produced using biotechnologyThey are proteins (including antibodies), nucleic acids used for therapeutic or in vivo diagnosticproduced by other than direct extraction from biological source

First Substance Approved For Therapeutic Use:biosynthetic 'human' insulin (humulin) made via recombinant DNA technology

a pharmaceutical product manufactured by biotechnologymethods (involving live organisms;bioprocessing);

CLASSIFICATIONAccording to biological roles of proteinsEnzymes – Catalyses virtually all chemical reactions i.e. 6GDH Transport proteins i.e. Haemoglobin of erythrocytes Contractile or Motile proteins i.e. Actin and Myosin Structural proteins i.e.Collagen Defense proteins i.e. Immunoglobulins and Antibodies Regulatory proteins i.e. insulin Nutrient and storage proteins i.e. Ovalbumin

Thrombolytic agents (tissue plasminogen activator) plasminogenplasmin protein involved in blood clot removal

Hormones (insulin, glucagon, growth hormone, gonadotrophins) CS Factor glycoprotein harmone binds to hemopoietic stem cellsHaematopoietic growth factors (Erythropoietin) gylcoprotein harmone controls erythropoiesis

Interferons (Interferons-α, -β, -γ) proteins relesed by lymphocytes

Monoclonal antibodies (Various)

SOME EXPLANATIONS………………

BIOPHARMACEUTICALS PRODUCTION

Biotechnology makes large-scale production of existing substances using microbial cells mammalian cell lines,tissues plant cell cultures, whole cultivation

Mechanism behind is TransgenicDNA recombinant technology

MECHANISM

Strengths:Access new manufacturing facilitiesHigh production rates/high protein yieldRelatively fast 'gene to protein' timeSafety benefits;no human pathogensStable cell lines/high genetic stabilitySimple medium (water, minerals & light)Easy purification

Weaknesses:No approved products yet (but Phase III)No final guidelines yet (but drafts available)

Threats:Food chain contaminationSegregation risk

PLANT BIOPHARMACEUTICALS

SOURCE

PRODUCTS

Very large and unstable molecules held by weak non-covalent forces

Easily destroyed by relatively mild storage conditions

Hard to obtain in large quantities

Elimination by B and T cells

Proteolysis by endo/exo peptidases

Small proteins (< 30 kD) filtered out by the kidneys very quickly

Unwanted allergic reactions may develop (even toxicity)

Loss due to insolubility/adsorption

Noncovalent Covalent

Denaturation - Deamidation

Aggregation - Oxidation

Precipitation - Disulfide exchange

Adsorption - Proteolysis

CHALLENGES IN PROTEINS

Storage

Delivery

Formulation

• Addition of stabilizing salts or ions (Zn+ for insulin)

• Addition of polyols (glycerol and/or polyethylene glycol) to solubilize

• Addition of sugars or dextran to displace water or reduce microbe growth

• Use of surfactants (CHAPS) to reduce adsorption and aggregation

Refrigeration

Freeze-Drying

Additives

STORAGE MECHANISM

PROTEIN FORMULATION

Protein sequence modification

(site directed mutagenisis)

PEGylation

Proteinylation

Peptide Micelles

Formulating with permeabilizers

1.Site Directed Mutagenesis:

Allows amino acid substitutions at specific sites in a protein

i.e. substituting a Met to a Leu will reduce likelihood of oxidation

Strategic placement of cysteines to produce disulfides to increase Tm

Protein engineering (size, shape, etc.)

E343H

2.PEGylation

+C

H-C

H-C

H-C

H-C

H-C

H-C

H-C

H-C

H-C

H | | | | | | | | | |O

H O

H O

H O

H O

H O

H O

H O

H O

H O

H

PEG is a non-toxic, hydrophilic, FDA approved, uncharged polymerIncreases in vivo half life Decreases immunogenicityIncreases protease resistance, solubility & stability

Peptide-PEG monomers

Peptide Peptide

O

R3HNH

O

R4HH3N+

O

R1HNH

O

R2HNH

O

O

R3HNH

O

R4HH3N+

O

R1HNH

O

R2HNH

O

Hydrophobic block Hydrophobic block

cont……

+

Protein Drug ScFv (antibody)

Attachment of additional or secondary (nonimmunogenic) proteins for in vivo protection

Increases in vivo half life (10X)

Cross-linking with Serum Albumin

Cross-linking or connecting by protein engineering with antibody fragments

3.Proteinylation

4.Formulation with permeabilizers

Salicylates (aspirin)

Fatty acids

Metal chelators (EDTA)

Anything that is known to “punch holes” into the intestine or lumen

DELIVERY

Polymeric drug delivery Microencapsulation Liposomal delivery Niosomal delivery

MECHANISM Proteins in pumps Oral protein delivery Nasal delivery Pulmonary delivery Ocular delivery Patch delivery

LEVELS OF TESTING

DRUG + receptor

BINDING

+ transductionsystem (secondmessenger; enzyme)

Biochemical Testing

Functional whole or part organs

Isolated Tissue Experiments

Anaesthetised Or Conscious Animals

Whole Animal Experiments

{Phase 0 (non-clinical)}Phase 1 (volunteers)Phase 2 (patients)Phase 3 (large scale multi-centre)Phase 4 (post registration monitoring)

NANO BIOPHARMACEUTICALS

Nanoparticles including various nanodimensional entities such as

molecular imprinted polymers

metallofullerenes

prodrug delivery

oral, injectable and implantable, pulmonary, and transdermal and

transmucosal delivery have come up.

THANK YOU...