Protein Therapeutics: Delivery

Devin Hudson

Delivery Methods

Intravenously Subcutaneously Suppository Intranasally

Orally*

Transinfection*

Liquid Filled Nanoparticles as a Drug Delivery Tool.

Venkatesan, N., Yoshimitsu, J., Ito, Y., Shibata, N. Takada, K. (2005)

Biomaterials. 26, 7154-7163.

Barriers to Oral Bioavailability

• Percent Bioavailability: BA%

• Poor Membrane Permeability

• Enzymatic Degradation

• Past Attempts: liposomes, nanoparticles, micro-spheres, hydragels, mucoadhesives, micro-emulsions

Concept

Erythropoietin (EPO)

1BUY1BUY1BUY

PDB: 1BUY

Hormone: Produced in Kidneys

Erythropoiesis

Porous Absorbents

Carbon Nano Tube

Carbon Nanohorn

Fullerenes

Other Porous Substrates: Silicon Dioxide, Charcoal, bamboo charcoal

Treatment

Jejunum: large surface area

Blood EPO measured via Jugular vein with ELISA

Formulation G: labrasol

Absorption Enhancers

Formulation A: CNT

Porous Absorbents

Formulation G: Casein

Protease Inhibitors casein vs lactoferrin

Conclusion

BA% = 11.5

Systemic Delivery of Secreated Protein by Grafts of Epidermal Keratinocyctes: Prospects for

Keratinocyte Gene Therapy.Fenjves, E. S., Smith, J., Zaradic, S. and Lorne, B. T. (1994)

Human Gene Therapy. 5, 1241-1248

Wikipedia.org

Concept

Transfect with recombinant apoE-HA1 (pSV2neo)

Graft skin

ELISA: Two Tests

Wikipedia.org

Keratinocyctes and Aythmic MiceStable Long Term Grafts

Effectively Transduced via retrovirus

Secretory tissue

Newborn Foreskin

Nude Mouse

Immune- deficient

No Rejection Response

Xenografts

Wikipedia

Fractionation – Ficoll 400

Non-fractionated: total

Small: basal compartment rich

Intermediate: poorly characterized

Large: terminally differentiated suprabasal cells

Basal compartment keratinocyctes excrete endogenous apoE

Mature Differentiated keratinocyctes do not excrete endogenous apoE

Recomibant apoE expressed by any transfected keratinocytes

Long Term Success

Blood Serum apoE after 28 days

Previous work: Viral promoters shut off over time

Conclusion

Higher Recombinant Expression in vivo

Expansion in suprabasal cells in grafts

Estimated that graft covering 2% of human skin could provide 6.5-8.9mg of recombinant protein per day.

Oral vs Graft

Pros: Easily Manage Dosing

Quit/Start/Change Treatment

Minimally Invasive

Lower Short Term Expense

Cons: Require On-going Care

Suffer from Varied Absorption

Pros: Doesn’t Require On-Going Care

Lower Long Term Expense

Less Margin for Patient Error

Less Risky than Systemic Transfection

Cons: Invasive

Treatment Can Not be Stopped Easily

Refrences

Skin Patch

Fenjves, E. S., Smith, J., Zaradic, S. and Lorne, B. T. (1994) Systemic Delivery of Secreated Protein by Grafts of Epidermal Keratinocyctes: Prospects for Keratinocyte Gene Therapy. Human Gene Therapy. 5, 1241-1248.

Review Paper

Leader, B., Baca, Q, J,. and Golan, D, E. (2008) Protein therapeutics: a summary and pharmacological classification. Nature Publishing Group. 7, 21-39.

Oral

Venkatesan, N., Yoshimitsu, J., Ito, Y., Shibata, N. Takada, K. (2005) Liquid filled nanoparticles as a drug delivery tool. Biomaterials. 26, 7154-7163.