NANOMEDICINE & DRUG DELIVERY SYSTEMSUNIT 1-PROSPECT OF NANOMEDICINE BIO-PHARMACEUTICALS
Seminar by R.DELMA JONES RUFINA II M.Tech-NST
PREAMBLE Biopharmaceuticals are medical drugs produced using biotechnology They are proteins (including antibodies), nucleic acids used for therapeutic or in vivo diagnostic produced by other than direct extraction from biological source
a pharmaceutical product manufactured by biotechnology methods (involving live organisms;bioprocessing);
First Substance Approved For Therapeutic Use: biosynthetic 'human' insulin (humulin) made via recombinant DNA technology
CLASSIFICATIONAccording to biological roles of proteins Enzymes 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. Immunoglobulinsand Antibodies Regulatory proteins i.e. insulin Nutrient and storage proteins i.e. Ovalbumin
SOME EXPLANATIONS Thrombolytic agents (tissue plasminogen activator) plasminogen plasmin protein involved in blood clot removal Hormones (insulin, glucagon, growth hormone, gonadotrophins) CS Factor glycoprotein harmone binds to hemopoietic stem cells Haematopoietic growth factors (Erythropoietin) gylcoprotein harmone controls erythropoiesis Interferons (Interferons-, -, -) proteins relesed by lymphocytes Monoclonal antibodies (Various)
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 Transgenic DNA recombinant technology
MECHANISM
PLANT BIOPHARMACEUTICALSStrengths: Access new manufacturing facilities High production rates/high protein yield Relatively fast 'gene to protein' time Safety benefits;no human pathogens Stable cell lines/high genetic stability Simple medium (water, minerals & light) Easy purification Weaknesses: No approved products yet (but Phase III) No final guidelines yet (but drafts available) Threats: Food chain contamination Segregation risk
SOURCE
PRODUCTS
CHALLENGES IN PROTEINSVery large and unstable molecules held by weak non-covalent forces Easily destroyed by relatively mild storage conditions Hard to obtain in large quantitiesElimination 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 Denaturation Aggregation Precipitation Adsorption Covalent - Deamidation - Oxidation - Disulfide exchange - Proteolysis
Storage
Formulatio n
Delivery
11
STORAGE MECHANISMRefrigeration Freeze-Drying AdditivesAddition 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
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.PEGylationPEG is a non-toxic, hydrophilic, FDA approved, uncharged polymer Increases in vivo half life Decreases immunogenicity Increases protease resistance, solubility & stabilityCH-CH-CH-CH-CH-CH-CH-CH-CH-CH | | | | | | | | | | OH OH OH OH OH OH OH OH OH OH
+
contPeptide-PEG monomers
Hydrophobic blockPeptide
Hydrophobic blockPeptide
O H H3N+ H R1 N H
R2 H N O H
O H R3 N H
R4
O H O H3N+ H R1 N H
R2 H N O H
O H R3 N H
R4 O O
O
3.ProteinylationAttachment 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
+
Protein Drug
ScFv (antibody)
4.Formulation with permeabilizersSalicylates (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
Biochemical Testing
LEVELS OF TESTING
DRUG + receptor + transduction system (second BINDING messenger; enzyme)
Isolated Tissue Experiments Functional whole or part organs Whole Animal Experiments
Anaesthetised Or Conscious Animals{Phase 0 (non-clinical)} Phase 1 (volunteers) Phase 2 (patients) Phase 3 (large scale multi-centre) Phase 4 (post registration monitoring)
NANO BIOPHARMACEUTICALSNanoparticles 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...
