Upload
rajan-bawa
View
223
Download
0
Embed Size (px)
Citation preview
Polymers Are Omnipresent
• Automobiles
• Food & Beverage
• Energy – oil, solar panels, wind turbines
• Computers & Telecommunications
• Medical
• Pharmaceuticals
Polymers in Medical Devices
• Syringes, needles
• Bandages & Dressings
• Equipment
• Prosthetics – Artificial Limbs
• Implants – Heart valves, Dental Implants
• Drug Delivery
Contact Lenses
• Traditionally – Monomer Mix Heat Cast Rods
• Discs (Buttons) Cut
• Chucked & Lathed One Side
• Re-Chucked & Lathed Other Side
• Polished/Buffed
• Hydrated and Residual Monomers Extracted
• Labor Intensive & Scratch Marks Interfere
with Resolution – Less Visual Acuity
SpinCasting
• Highly Finished (Optical Surface)
• Monomer Mix Injected with UV Initiator
• Under Nitrogen Blanket – prevents “poisoning”
• Free Spin Surface Generated – Parabola
• Dynamic Equilibrium Established
• Polymerized by UV Lights
• Edges Finished
• Hydrated & Residual Monomers Extracted
• Sterilized & Vialed
SpinCasting (Wichterle)
• Bausch & Lomb Acquired Rights
• 25cents + $1 for vial – Sold for $90/lens
• Lathed Lens Cost = $9.00/lens – Sold for $90
• B&L Allowed Competitors to Survive
• Johnson & Johnson Developed Cast Molding
Cast Molded Contact Lenses
• One Mold Placed on Top of the Other
• Monomer Mix in Between
• Heat Initiated Polymerization
• Cost in Between Spinning & Lathing
• True Sphere Resulted in Superior Optics
• Better Resolution Than Parabola
• Superior Visual Acuity
Ocular Drug Delivery Systems
• Eye Maintains Homeostasis of 7.5 microliters
• Typical Drop Size is 50 microliters
• Excess Fluid Cleared from Eye
• Rolls down cheeks or flows down Naso-Lacrimal
Duct
• Severe Eye Infections – Patient Hospitalized
• Nurse Administers Medication every 5 mins!
Previous Attempts
• Gels – short lasting, interference with vision
• Creams – same as gels
• Contact Lenses Soaked in Drug Solutions – not
long lasting enough
• Lacrisert – Merck – dry eye interferes with vision
• Ocusert (Pilocarpine for Glaucoma) – Alza Corp.
– flat oval falls out during use
Requirements of Ocular Drug Delivery
Systems
• Sterility
• Comfort
• Versatility – long lasting/short lasting
• Non-Interference With Vision
• Oxygen Permeability
• Should not fall out of eye during use
Minidisc
• Cast Molded Shaped Concavo-Convex
• Mini “Contact Lens”
• Slightly Steeper Base Curve Against Eye –
slight suction
• Flexibility of Choice of Monomer Mix
allows Variable Physico-Chemical
Properties
• Hydrophobic to Hydrophilic Drugs
• Sterile – Gamma Irradiation
Implications For Ocular Health
• Many Eye Camps in India
• People from Rural Areas Transported
• Infection Rate Very High
• Have to be Retained in Clinic
• Interference with Life and Economic
Hardship
• Treat with Minidisc & Send Home
General Entrepreneurship
Challenges
• Funding
• IP Protection
• Legal/SEC Compliance
• Personnel
• Cheaper Competition Global Marketplace – China & India
ADDITIONAL CHALLENGES IN
LIFESCIENCES• Regulatory Agencies – FDA/USDA
• Rigorous SOPs
• Stringent Quality Assurance Systems
• On-Going Training of Personnel
• Periodic On-Site Inspections
• Establishing Credibility as “Foreigner”
• Questionable Practices by Foreign Based
Firms
REGULATORY PROCESS
• PK/TK Studies
• Acute Toxicity (1 month)
• IND
• Chronic Toxicity (3,6,9 mths – 2 species)
• DART Studies for NCEs, Seg I, II, III
• NDA (New Drug Approval)
• Carcinogenicity Studies
REGULATORY PROCESS
(cont)
• Human Clinical Trials
• PHASE –I (normal volunteers)
• PHASE –II (diseased patients, single
center)
• PHASE –III (diseased patients, multi-
center)
• NDA APPROVAL
Cheaper Competition Global Marketplace –
China & India
• Language (China not India)!
• Unfamiliarity with Common Formulation
Practices
• Unethical Business Practices
• Studies Have to be Repeated in
Compliance with FDA Regulations
• Small Start-Ups Go Belly-Up!