Injectable Polymer Scaffolds – An Approach to Cartilage ... · Cartilage Anatomy zComposed of...
Transcript of Injectable Polymer Scaffolds – An Approach to Cartilage ... · Cartilage Anatomy zComposed of...
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N.K.O.B.®(New Kim on the Block)
Injectable Polymer Scaffolds – An Approach to Cartilage Tissue
Engineering
Mark Shreve, Jessica Yankovich, Mira Kim
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Background
Millions of Americans suffer from trauma, disease, or malformation of cartilage tissueCartilage provides
Mechanical supportDistributes forces during loadingLubrication to the joint
Cartilage lacks the ability to regenerate itselfCurrent treatments are not seen with high success rates
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Project Aim
GoalRegenerate cartilage in knee to restore full functionality in a minimally invasive manner
PathwayEmploy a procedure involving an injection of a biodegradable cell/scaffold/growth factor composite into defect site
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Cartilage AnatomyComposed of four components
Chondrocytes10% of total volume of cartilage tissue
CollagenProteoglycansWater
80% of total volume of cartilage tissue
Articular Surface
Chondrocytes
Calcified Zone
Subchondral Bone
Tide mark
Superficial Zone (10-20%)
Middle Zone (40-60%)
Deep Zone (30%)
Articular Surface
Chondrocytes
Calcified Zone
Subchondral Bone
Tide mark
Superficial Zone (10-20%)
Middle Zone (40-60%)
Deep Zone (30%)
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Chondrocytes
Cartilage receives no neural impulses No nerve supplyNo vascular supply
Cannot signal repair
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Collagen
Macromolecule with triple helical structuresType II is prevalent in articular cartilageGives cartilage shear and tensile propertiesMaintains proteoglycan in extracellular matrix
http://www.rcsb.org/pdb/molecules/pdb4_1.html
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Proteoglycan
Complex macromoleculesLong protein chain100s of bound glycosaminoglycans
Promotes proteoglycan-collagen and proteoglycan-proteoglycan interactionsHolds the tissue togetherGives mechanical properties
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Types of CartilageFibrocartilage (type I)
Non-load bearing regionsEarNose
Less resilient mechanical properties
Hyaline cartilage (type II)Prevalent in all diarthroidaljointsResilient mechanical properties
www.silent.se/ soundscapes.php
http://netscape.lhj.com/lhj/story.jhtml?storyid=/templatedata/bhg/story/data/6501.xml&catref=cat410032
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Cartilage Defects
Injury to articular cartilageCartilage lesionsOsteoarthritis
Cartilage lacks the inherent means to regenerate itself
Many cartilage defects affect underlying subchondral bone
Ref: http://www.orthogastonia.com/patient_ed/html_pages/knee/knee_cartilage_surgery.html
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Cartilage lesions
Underlying bone is often exposedMay result in unbalanced jointLeads to further damage with surrounding tissues
http://www.carticel.com/patients/learning/aboutcartdamage.asp
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Osteoarthritis
Noninflammatorydegenerative joint diseaseBones rub and underlying subchondral bone is warn awayLeads to further complications
http://www.zimmer.com/ctl?op=global&action=1&id=1979&template=PC
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Current Therapies
Reparative
TemporaryProduces fibrocartilage
Arthroscopic debridementAbrasion arthroplastyMicrofracturing http://www.orthogastonia.com/patient_ed/html_pages/knee/knee_cartilage_surgery.html
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Current Therapy
RestorativeNot highly successfulChondrocytes migrate from defect site
OsteochondralautograftsOsteochondral allograftsAutologous chondrocyteimplantation
http://www.orthogastonia.com/patient_ed/html_pages/knee/knee_cartilage_surgery.html
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Solution
Our goal:Mimic the in vivo environment of the knee Use an injectable polymer with two regions (bone and cartilage) that contains autologouscells encapsulated with growth factors
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Production Process
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Tissue Engineering
Progenitor Cells Growth Factors
3D Matrix scaffold
Vascularization
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Cells harvested from patient
Cells Proliferated in vitro Cells encapsulated in
gelatin microparticles
Polymer mixed with crosslinking reagent
prior to injection
Polymer/cell suspension injected
arthroscopically
Polymer crosslinks in situ forming hard
scaffold
SubchondralBone Region
ArticularCartilage Region
Over a few months scaffold degrades and cartilage regenerates
Subchondral Bone Region
Articular Cartilage Region
Overview of Process
Cells and growth factors seeded into injectable
polymer
Overview of Process
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Harvesting/Proliferation of Chondrocytes
•Elapsed Time ~ 5 weeks
http://www.orthogastonia.com/patient_ed/html_pages/knee/knee_cartilage_surgery.html
Biopsy of cartilage from non-
loadbearing region
Biopsy cut into pieces <2mm and placed in culture
flasks
Culture media containing
Collagenase and DNase added
Flasks placed in incubator for 24
hrs.
Media strained with 70µm cell
strainers
Elutate centrifuged to isolate
chondrocytes
Cells resuspended in medium containing
ascorbic acid and antibiotics
Cells centrifuged again
Cells resuspended in medium and cultured for 4 weeks at 37°C
Flasks washed with PBS and
lifted with Trypsin
Centrifuged and resuspended in
DMEM for microencapsulation
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Harvesting/Proliferation of BMSC’s
http://my.webmd.com/hw/health_guide_atoz/hw200221.asp
•Elapsed Time ~ 5 weeks
•Concurrently with Chondrocyte culture
Bone Marrow aspirates (20mL) obtained from hip
Aspirate mixed with a-MEM with 10% FBS and
antibiotics
Cells then resuspended in a-MEM in 20-gauge
needles
Suspension added to culture flask with medium containing
ascorbic acid and bFGF
Cells cultured 4 weeks at 37°C in
incubator
Cells washed with PBS and lifted with Trypsin
Centrifuged and resuspended in
medium ready for microencapsulation
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Preparation of Gelatin Solution
30% (w/v) porcine gelatin solution in ddH2O prepared
30g gelatin added to 100mL water 0.25 g at a time
Solution allowed to solidify at R.T. then stored
at 4ºC till later use
An 11% (w/v) solution is then made from the
30% solution
DMEM and 30% Gelatin solution warmed to
50ºC
33.33g Gelatin and 56.67 mL DMEM added
to beaker
pH adjusted to 7.2 with either NaOH or HCl
Resulting solution is sterilized by vacuum
filtration in Laminar Flow Hood into a sterile media
bottle
http://www.macbicnj.com/corning/90307.htm
Stored at 4ºC till Microparticle formation
•Elapsed Time ~ 2 hrs
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Encapsulation and Surface Crosslinking
45mL of 11% gelatin warmed to 37ºC and
diluted with 5mL sterile suspension of cells in DMEM
Gel/cell solution placed in sterile 30mL syringes with 22 gauge
needles
Allowed to cool to 34ºC
400mL sterile mineral oil with 5mM DSP
(crosslinks on surface) prepared at
10ºC
Solution then dripped into oil to form microparticles
containing cells
Causes microparticlesto form due to hydrophobic
interactions and harden due to
temperature change
Microparticle solution filtered on 80µm meshes
Transferred to PBS at 15ºC agitated 2 min
Microparticles filtered again and placed on absorbent
towels in ice bath
•Elapsed time ~ 2 hrs
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Microparticle Chemistry
NH2
gelatin
NH2
gelatin
NH 2
gelatin
NH 2
gelatin
HN
gelatin
C
O
CH2CH2 SS CH2CH2 C
O
gelatin
NHHN
gelatin
C
O
CH2CH2 SS CH2CH2 C
O
gelatin
NH
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Gelatin MicroparticleContaining Cells
DSP
DSP
DSP
DSP
DSPDSP
DSP
DSP
DSP
DSP
DSP
DSP DSP
DSP
DSP
DSP
DSPDSP
DSP
DSP
DSP
DSP
DSP
DSP
DSP
DSP
DSP
DSP
DSPDSP
DSP
DSP
DSP
DSP
DSP
DSP
View at MicroparticleSurface
Cross-Section of Microparticle
DSP Crosslinked Layer
Cells
Inner uncrosslinkedGelatin
Crosslinking at the Surface
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Gelatin Microparticles
This membrane will help maintain the mechanical integrity for a short timePrevents enzymatic degradation mainly by steric hindrancePrevents reverse thermal gelation of the particle by holding the gelatin molecules together
Liang et al. Genipin-crosslinked gelatin microspheres as a drug carrier for intramuscular administration: In vitro and in vivo studies J Biomed Mater Res 65A: 271–282, 2003
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Preparation of PPF
Poly(propylene fumarate) is prepared in a two step reaction scheme:
First is formation of a diesterSecond is a transesterification reactionPPF will be prepared with both β-TCP particles and as a copolymer with poly(ethylene glycol)
Payne, R.G. et al. Development of an injectable, in situ crosslinkable, degradeable polymeric carrier for osteogenic cell populations, Part 2. Biomaterials 23: 4373-4380, 2002.
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Polymer Chemistry
The reactions involved in the production of PPF are as follows:
MeMe O
O
O
O OH
OH
EOEtEtO
O
O
ECH CH2H3C
OH
OH+
DEF PGBHPF
+ CH2H3C OH
Ethyl alcohol
ZnCl2Hq
MeMe O
O
O
O OH
OH
EOEtEtO
O
O
ECH CH2H3C
OH
OH+
DEF PGBHPF
+ CH2H3C OH
Ethyl alcohol
ZnCl2Hq
Step 1 – formation of Diester
Step 2 – transesterification
MeMe O
O
O
O OH
OH
E
BHPFPPF
+High Temp
Low PressureCH CH2H3C
OH
OH
PG
O
O
HO OOH
O
n
O
O
HO OOH
O
n
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Microparticle Seeding and Injection Preparation
Table 1. Relative Amount of each Component in Crosslinking ReactionComponent AmountPPF/β-TCP or PPF-co-EG 1.0 gN-VP 0.1 gBenzoyl Peroxide 0.0015 gDMT 2.5 µL
•This procedure is performed directly before injection
PPF composite, N-vinylpyrrolidinone (N-VP) and
benzoyl peroxide (BP) sterilized with UV light 2 hrs. Dimethyl p-toluidine (DMT)
also obtainedBP and the other half of N-VP are mixed together
PPF, DMT and half of N-VP mixed
together
Appropriate amount of
Microparticles and Microspheres
obtained
Solutions briefly mixed
Microparticles and Microcapsules added to the
solution
Resulting solution is loaded into a
syringe and ready for injection
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Polymer Chemistry
The PPF is crosslinked in situ using N-VP and benzoyl peroxide as an initiator, and DMT as an accelerator
CH2HC
O N
CH2HC
OO NO
OHO O
OH
O
n
O
OHO O
OH
O
n
+ BP initiatorDMT accelerator
O
OHO O
OH
O
n
CH2
HC N
O
O
OHO O
OH
O
n
R
R
O
OHO O
OH
O
n
CH2
HC N
O
O
OHO O
OH
O
n
O
OHO O
OH
O
n
O
OHO O
OH
O
n
CH2
HC N
O
CH2
HC N
OO
O
OHO O
OH
O
n
O
OHO O
OH
O
n
R
R
PPF N-VP
CrosslinkedPPF
+ Heat
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Close-up of Injection Procedure
Subchondral Bone Region
Articular Cartilage Region
Subchondral cartilage defect is first cleaned out and prepared for injection
PPF/β-TCP composite containing Encapsulated BMSC’s and BMP-2 microspheres injected into defect site
PPF Crosslinking reaction then occurs in situ hardening the polymer in 20 minutes
PPF-co-EG composite containing encapsulated chondrocytes and TGF-βmicrospheres injected ontopof lower layer
PPF crosslinking occurs in 20 minutes hardening the polymer
Gelatin Microparticlescontaining cells then disperse approximately 1 hr. post injection at 37ºC and pores are created also securing material into place
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Temperature Profile
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Polymer Crosslinking Reaction
Heat released during cross-linking reactionAt increased temperatures, gelatin undergoes reverse thermal gelation
Gelatin becomes fluidCell survival decreases
DSP cross-linking on surface of microcapsules in order to maintain mechanical integrity
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Temperature Profile of Polymer Crosslinking Reaction
Payne, R.G. et al. Development of an injectable, in situ crosslinkable, degradeable polymeric carrier for osteogenic cell populations, Part 2. Biomaterials 23: 4373-4380, 2002.
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Cell Survival vs. Temperature
0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60
Tim e (m in)
Perc
ent S
urvi
val (
%) 42 C
41 C
40 C
39 C
38 C
37 C
Lin et al. Stability of Heating Temperature on Cytotoxicity. Int. J Radiation Oncology Biol. Phys. Vol. 13, pp. 1869-1873. 1987.
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Temperature Profiles
Maximum temperature of polymer = 45.7ºC after 562 s (9.4 min)Polymer is above critical temperature of 37ºC for less than 5 minutesModel behavior of temperature rise within injection as a function of time in order to determine cell viabilityModel can determine optimal injection temperature
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Mathematical Model
CartilageCartilage
Bone
x = -L x = L
2
2
xT
tT
∂∂
=∂∂ α2
2
xT
tT
∂∂
=∂∂ α
pCq
yT
xT
tT
ρα
•
−⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂
=∂∂
2
2
2
2
2
2
yT
tT
∂∂
=∂∂ α
Air (h = 0)
Polymer
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Assumptions
Boundary Conditions:
From symmetry: One-dimensional inside term:
Heat generation term:
tzT
tLxu z
TxT
,0, == ∂∂
=∂∂ αα
( ) oTxT =0,
)(2
2
tqxT
tT
+∂∂
=∂∂α
( ) ( )tLTtLT xx ,, −=
( ) tetq 75.21450 −=
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Inside Term
From separation of variables:
Using Fourier series and rules of orthogonality:
Unknown K is determined from outside equation
( ) ( ) ( ) ( )∑ ∑+++= xtBxtADxtCtxT nnnn λλ cossin,
( ) ( )∑ −−
⎥⎥⎥
⎦
⎤
⎢⎢⎢
⎣
⎡⎟⎠⎞⎜
⎝⎛+−
+⎟⎟⎠
⎞⎜⎜⎝
⎛−= xe
Lk
kKue
kkKtxT n
t
n
otk λ
λ
α
ααλ sin2,
22 2
1
2
1
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Outside Term
In cartilage region in one dimension:
Taking the Laplace transform:
From boundary conditions:
2
2
xT
tT
∂∂
=∂∂ α
zszs
BeAeT αα−
+=ˆ
( ) ( ) ( ) ( ) ( ) ( )zs
esGL,sTsFsGsFszT α−
==⋅= and where,ˆ
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Initial Solution
By using the initial boundary condition:
From the theory of convolution:
Therefore the final equation for the outside term:
( ) ( )sLTsT inout ,,0 =
( ) ( ) ( ) ( ) ( )∫ −=∗=t
dgtftgtftzT0
, ξξξ
⎥⎥⎦
⎤
⎢⎢⎣
⎡⎟⎟⎠
⎞⎜⎜⎝
⎛++++⎟
⎠⎞
⎜⎝⎛
Π−⎥
⎦
⎤⎢⎣
⎡⎟⎠⎞
⎜⎝⎛
Π− − tk
tktktktk eeee
zte
kk
tzerfcK
2
222
2 43
24
2
1 222122
2 ααα
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Inside vs. Outside
By using boundary condition
These two equations are used to solve for the unknown constant K
( ) ( )tLTtT inout ,,0 =
( ) ⎟⎟⎠
⎞⎜⎜⎝
⎛−= − tke
kk
KtLT 2
2
1,α
( )Π
−=KtTout 2,0
tkek
kK 2
2
1
21
−
⎟⎠
⎞⎜⎝
⎛Π
+=
α
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Final Solution
The temperature flux is:
All constants knownα is thermal diffusivity of water (cartilage is 80% water)L is 0.035 cm (average size of defects)
( ) xeL
kke
k
kT
xT
nt
tko
n λ
αα
αλ∑⎟⎟⎟⎟⎟
⎠
⎞
⎜⎜⎜⎜⎜
⎝
⎛
⎟⎠⎞⎜
⎝⎛+
⎟⎠
⎞⎜⎝
⎛Π
+−
=∂∂
−
cos
212
2
2
2
1
2
1
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Expected Behavior
42º C
t = 1, 9 min
t = 2, 8 min
t = 3, 7 min
t = 4-6 min
37º C
Based on the internal body temperature of 37 ºC and the temperature rise to 42 ºC
due to polymerization, the expected temperature behavior is plotted.
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Future Work
Inside term to be solved in two dimensionsCylindrical coordinates may be simpler
Graphical representation of temperature profile during cross-linking reactionMicroparticle temperature profile determined to analyze cell survival with given sizes
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Porosity
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Porosity
a measure of the voids orratio of volume of openings/ total volume of the materialIncreasing porosity will
Allow greater amount of cells to be injectedDecrease mechanical stability
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Networking
Creating Pores within the Polymer Structure
High PorosityLow porosity Acceptable Porosity
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Cartilage Modeling
Compressive modulus: 0.4 – 1.5 MPa
Mechanical Properties of PPF
30 % porosityCompressive modulus: 28.7 + 9.1 MPa
80% porosityCompressive modulus: 0.11+ 0.02 MPa
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Mechanical Properties of PPF
(Assuming linear relationship)
Porosity range: 77-75%
y = -0.5718x + 45.854
0
5
10
15
20
25
30
35
40
0 20 40 60 80 100
% porosity
Com
pres
sive
Mod
ulus
(M
Pa)
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Amount of Microcapsules Needed
After polymerization, microcapsules form the void space Example: 77% porosity
77 volume % microparticles23 volume % PPF/β-TCP or PPF-co-EG
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FDA Approval Process
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Regulation and Classification
CDRH (Center for Devices and Radiological Health)
Medical Device
Class IIIImplant lacks safety and effectiveness supportRisky side effects of implantPre-Market Approval
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Pre-Market Approval
Modular PMANon-clinical studies
Laboratory experimentsProduction of materialsAnimal testing
Clinical studiesVoluntary patients
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FDA Approval Modeling
Uses two-stage stochastic modeling
1st stage decision variables“Here and Now” decisionsNumber of laboratory technicians and experiments
2nd stage decision variablesMade after an outcomeWhether to continue or not post failure
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1st Stage Decision Variables
10, 5, or 2 laboratory techniciansAffect cost, time, but not probability
70, 60, or 45 pre-FDA experimentsAffect cost, time, and probabilityMore experiments provides for greater probability of success
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1st Stage Decision Variables
Stage One Variables
Determine Number of
workers
1 PhD10 Lab Technicians
$480,000
1 PhD5 Lab Technicians
$275,000
1 PhD2 Lab Technicians
$152,000
Determine Number of
Experiments
Determine Number of
Experiments
70 Experiments$200,00090 Days
60 Experiments$170,00075 Days
45 Experiments$100,00055 Days
Determine Number of
Experiments
70 Experiments$200,000180 Days
60 Experiments$170,000150 Days
45 Experiments$100,000110 Days
70 Experiments$200,000450 Days
60 Experiments$170,000375 Days
45 Experiments$100,000275 Days
Begin Pre-FDA Experimentation
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Pre-FDA Experiments
45 experiment decisionThis set will contain the base number and type of experiments, deemed minimally essential prior to PMA filing and are as follows:
1. Synthesis of Poly(propylene fumarate)2. Gelatin Microencapsulation Histology3. Evaluation of cell growth on polymer4. Growth Factor encapsulation and effect5. Basic biocompatibility tests
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Pre-FDA Experiments
60 experiment decisionIn addition to the aforementioned experimental sets, 3 more additional experiment types will be performed for the 60 experiment decision, and are as follows:
6. Evaluation of polymer mechanical properties pre- and post-implantation
7. Evaluate the optimal cell seeding density of the gelatin microparticles
8. Evaluate optimal growth factor and cell density ratio within the construct
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Pre-FDA Experiments
70 experiment decisionIn addition to all the previously described experiments for 45 and 60, 2 additional experiment types will be performed as follows:
9. Evaluate the degradation rate of the polymer versus the cell tissue ingrowth
10. Evaluate the longterm success rate of procedure on white rats
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PMA Application Review
$250,000180 Days
PMA Filing
Re-apply for PMA Application
Review$62,000
180 Days
Abandon Project
Upon rejection of PMA Application, FDA refunds
75% of initial fee.
Failure due to data inconsistencies and
vacancies5%
Failure due to consumer needs5%
Approval Granted90%
Approval Granted99%
Failure1%
PMA Filing Decision Tree Example pathway
10 lab techs, 70 exp decision
Time so far: 180 days
Cost so far: $250,000
Probability so far: 0.9
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Module 1 Testing$500,0003 years
Module 2
Module 1 testing$500,0003 years
Abandon Project
Failure due to polymer problems
5%, 7%, 10%
Failure due to gelatin microparticles
7%, 9%, 15%Approval Granted
70%, 60%, 35%
Approval Granted90%, 85%, 75%
Failure due to polymer synthesis4%, 7%, 10%
Failure due to growth factor microspheres5%, 7%, 15%
Change polymer synthesis procedure$40,0002 months
Change gelatin formulation/
seeding density$20,0001 month
Change microsphere fabrication procedure$60,0003 months
Reapply for Module 1
Failure due to microparticle
synthesis3%, 5%, 9%
Failure due to growth factor microspheres
3%, 3%, 6%
Abandon Project Abandon Project
Failure due to poor cell adhesion
7%, 9%, 13%
Failure due to poor cell survival in encapsulated
microparticles6%, 8%, 12%
Attach RGD peptides to
polymer surface$20,0002 months
Abandon Project
Module 2
Module 1
Time so far: 2520 days
Cost so far: $1,970,000
Probability so far: 0.0405
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Module 2
Time so far: 4800 days
Cost so far: $3,700,000
Probability so far: 0.000255
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Module 3
Total time: 8267 days
Total Cost: $12,000,000
Total Probability: 0.0000306
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FDA Approval Modeling
Number of paths possible
5,290 different paths possible through the decision trees for each first stage decision variable (47,610 total pathways)
2,970 lead to success and 2,320 lead to failure
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10 Lab Technicians
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
-50 -30 -10 10 30 50 70 90 110 130 150 170 190 210 230 250 270 290 310 330 350
NPV (million $)
10 techs 70 exp10 techs 60 exp10 techs 45 exp
Risk Curve for 10 Lab Techs
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5 Lab Technicians
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
-50 -30 -10 10 30 50 70 90 110 130 150 170 190 210 230 250 270 290 310 330 350
NPV (million$)
5 techs 70 exp5 techs 60 exp5 techs 45 exp
Risk Curve for 5 Lab Techs
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2 Lab Technicians
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
-50 -30 -10 10 30 50 70 90 110 130 150 170 190 210 230 250 270 290 310 330 350
NPV (million $)
2 techs 70 exp2 techs 60 exp2 techs 45 exp
Risk Curve for 2 Lab Techs
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Comparison at 70 Experiments70 Experiments
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
-25 -5 15 35 55 75 95 115 135 155 175 195 215 235 255 275 295 315 335
NPV (million $)
10 techs 70 exp5 techs 70 exp2 techs 70 exp
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FDA Approval Modeling
Shortest pathPath in which approval is met with no failures using 10 lab techs and 45 experiments
Total Time: 4250 days or 11.6 yearsENPVcost: $4.4 millionENPV: $1130.4 million
Cheapest PathPath in which approval is met with no failures using 2 lab technicians and 45 experiments
Total Time: 4470 days or 12.2 yearsENPVcost: $3.96 millionENPV: $1012.8 million
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FDA Approval Modeling
Longest pathPath in which every failure possible is met using 2 lab techs and 70 experiments
Total Time: 11483.5 days or 31.5 yearsENPVcost: $8.7 millionENPV: -$8.7 million
Most Expensive PathPath in which every failure possible is met using 10 lab technicians and 70 experiments
Total Time: 9060 days or 24.8 yearsENPVcost: $18.6 millionENPV: -$18.6 million
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Business Plan
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Business Goals
Treatment of cartilage deficiencies using autologous cultured chondrocytesFDA Approval Provide non-invasive surgery at a competitive cost to be covered by insuranceBreak even point after 2-3 years Expand company over time to increase profit and production
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Business Plan
Culture and grow cells in facilitiesShip materials and cultured cells to hospitalsTrain surgeons on handling and preparation of scaffoldBase cost on the culturing of cells and materials
Price will be influenced by market demand and competitor’s prices
Fees to be covered by health insurance by patient
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Demand
17 million people reported have knee problems in 2000Total knee replacements cost insurance companies $41 billion annuallyOsteoarthritis leading chronic condition in elderlyCartilage repair has extremely limited treatments available
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Competition
Carticel®Autologous cultured chondrocytesFirst company to have FDA approval for cell therapeuticsMany insurance companies cover the treatment
Chondrocytes cultured and regenerated in defective site
Only major competitorAverage cost of their services - $10,360
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Strength of N.K.O.B.®
Non-invasiveReduced surgery costs, recovery timeFewer revisits to physicians
Regeneration lasts longer than knee replacements
Advantageous for younger patients
Treatment will allow repair to underlying bonePricing model will account for both strengths and weakness in determining selling price
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Current Costs
Total knee replacement: $25,000Other arthroscopic surgeries: $5,000-$10,000Carticel® treatment: $26,000
Genzyme Tissue Repair fee: $10,360First year Carticel® brought in $29 million in sales136 million people have insurance companies that cover Carticel® treatment
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Selling Price
Pricing ModelBased on production costs, investments, FDA and clinical trial costsUses superiority and inferiority functionsEvaluates current demand for treatment and approximates increase in demandUses competitor’s prices as basis for estimation
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Capital Investment
Major Cost – construction of new facility 2 major laboratories, 1 animal storage, 1 cellular storage, 3 offices10,000 square feet Construction + furnishings = $3 million
Other investment costs:Equipment: $76, 300
FCI: $3 million
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Clinical Studies Cost
Cost Cost/5 yrs 1st Stage Labor $630,000 $3,150,000 750 Patients $50,000 $37,500,000 Hospital Fees ($10,000 per patient) $10,000 $7,500,000Utilities (Refrigeration) $12,000 $60,000 Misc. Operating Costs $5,000 $25,000 2nd Stage Labor $950,000 $4,750,000 750 Patients $50,000 $37,500,000 Hospital Fees ($10,000 per patient) $10,000 $7,500,000Utilities (Refrigeration) $12,000 $60,000 Marketing $10,000 $50,000 Misc. Operating Costs $5,000 $25,000 Total $98,120,000
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Production Costs
Raw material cost per implantCell harvesting - $167.49Polymer production and cross-linking - $5.36Gelatin microcapsules and growth factor microsphere - $250.66
Total production cost per implant$423.52
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Pricing ModelModel uses demand and selling prices of competitors as well as superiority and inferiority functions
( ) ( ) ( )tdDpdpt αβ ⋅−=⋅ 1211
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 1 2 3 4 5 6
Time (years)
α(t)
β(t)
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Pricing Model
Pricing model manipulated to allow break-even point after three years
p2=$10,360/implantD=25,000 implantspc=$423.50/implantFCI = $3 millionFDA+clinical trials = $100 million
Selling price, p1, of N.K.O.B.® services: $11,000Surgery cost will be comparable to arthroscopic surgery ($5,000 - $10,000)
FDAFCIpp
Dppcpp
Dppi ii
i
ii
i +=⎥⎦
⎤⎢⎣
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3
1 21
2
21
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αβα
αβα
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Cash Flow
Year
Raw Material Cost (2%
inflation rate) # of implants Revenue Total Production
Cost Cash Flow 1 $423.50 3000 $33,000,000 $2,025,500.00 $30,974,500.00 2 $431.97 3450 $38,709,000 $2,137,296.50 $36,571,703.50 3 $440.61 3968 $44,515,350 $2,395,117.79 $42,120,232.21 4 $449.42 4563 $51,192,653 $2,697,542.17 $48,495,110.33 5 $458.41 5247 $58,871,550 $3,052,285.97 $55,819,264.41 6 $467.58 6034 $67,702,283 $3,468,400.44 $64,233,882.49 7 $476.93 6939 $77,857,625 $3,956,502.72 $73,901,122.65 8 $486.47 7980 $89,536,269 $4,529,046.69 $85,007,222.49 9 $496.20 9177 $102,966,710 $5,200,640.77 $97,766,068.79 10 $506.12 10554 $118,411,716 $5,988,420.62 $112,423,295.37
Raw material prices reflect 2% inflation rate
Cash Flow = Revenue - Total Production Cost
Demand for implants modeled after Carticel® demand
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Cumulative Cash Position
-200000000
-100000000
0
100000000
200000000
300000000
400000000
500000000
600000000
-20 -15 -10 -5 0 5 10 15
Time (yrs)
$
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Summary
GoalsProvide non-invasive solution to cartilage and bone repair at competitive pricesFDA ApprovalProfit
AdvantagesComparably non-invasive and affordable
Selling Price$11,000 plus approximately $5,000 in surgery fees
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Thanks to…
Dr. Bagajewicz
Dr. Sikavitsas
Kim Fink
Chem-E class
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Any Questions?