Sandro Rusconi

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Sandro Rusconi
UNIFR Rusconi 2003
1972-75 School teacher (Locarno,
Switzerland) 1975-79 Graduation in Biology UNI
Zuerich, Switzerland 1979-82 PhD curriculum UNI
Zuerich, molecular biology 1982-84 Research
assistant UNI Zuerich 1984-86 Postdoc UCSF, K
Yamamoto, (San Francisco) 1987-91 Principal
Investigator, UNI Zuerich 1994-today Professor
Biochemistry UNI Fribourg 1995-today Director
Swiss National Research Program 37 'Somatic Gene
Therapy' 2002-03 Sabbatical, Tufts Med. School
Boston and Univ. Milano, Pharmacology
Department 2002-05 President Union of Swiss
Societies for Experimental Biology (USGEB)
Feb 19, 2003 ECPM Basel
2003 Gene therapy turning teenage, what have we
learned?
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Genetics has been used since millennia,Molecular
Biology, only since 30 years
UNIFR Rusconi 2003
100000 b.C. Empirical genetics
10000 b.C. Biotechnology
2000 a.d. Molecular biology
2001 a.d, Genomics
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1 Gene -gt 1 or more functions
UNIFR Rusconi 2003
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Recap what is a gene?a regulated machine for
RNA production
UNIFR Rusconi 2003

• To fulfil its role, a transferred gene must
  include
• regulatory sequences for Tx initiation
• proper signals for RNA maturation/transport
• proper signals for mRNA translation

coding
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regulatory
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1 Organism -gt more than 105 genetically-controlle
d Functions
UNIFR Rusconi 2003

• 1 Cm3 of tissue
• 1'000'000'000 cells!

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Reductionistic molecular biology paradigm(gene
defects and gene transfer)
UNIFR Rusconi 2003

• Gene transfer implies either
• transfer of new function, or
• transfer of restoring function, or
• transfer of interfering function

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Examples of inheritable gene defects
UNIFR Rusconi 2003
Polygenic defects Type estimated ( frequent )
min - max Diabetes poly 1 - 4
Hyperurikemia Multi 2 - 15 Glaucoma poly 1 - 2
Displasia Multi 1 - 3 Hypercolesterolemia Mul
ti 1 - 5 Syn- Polydactyly poly 0.1 - 1
Congenital cardiac defects Multi 0.5 - 0.8
Manic-depressive psychosis Multi 0.4 - 3
Miopy poly 3 - 4 Polycystic
kidney poly 0.1 - 1 Psoriasis Multi 2 - 3
Schizofrenia Multi 0.5 - 1 Scoliosis Multi 3
- 5
Monogenic defects estimated ( rare )
min - max Cystic fibrosis, muscular
dystrophy immodeficiencies, metabolic diseases,
all together Hemophilia... 0.4 - 0.7
Predispositions Type estimated min - max ()
Alzheimer Multi 7 - 27 () Parkinson Multi 1 -
3 () Breast cancer Multi 4 - 8 () Colon
Carcinoma Multi 0.1 - 1 ()
Obesity Multi 0.5 - 2 () Alcolholism/ drug
addiction Multi 0.5 - 3

• Ergo
• every person bears one or more latent genetic
  defects
• many defects are not manifest but lead to
  predispositions
• there are also protective predispositions

Sum of incidences min - max (all
defects) 32 - 83
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Not only the genome determines the health
status...
UNIFR Rusconi 2003

• also acquired conditions may have a genetic
  component that modulates their healing
• trauma
• fractures
• burns
• infections

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The major disease of the 21st century Ageing
UNIFR Rusconi 2003

• This major challenge means
• higher investments
• more financial returns
• long term treatment
• customised treatment
• social security dilemma

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The THREE missions of medicine
UNIFR Rusconi 2003
Prevention

'Molecular Medicine' Application of the
know-how in molecular genetics to medicine
Diagnosis


Therapy
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The FOUR eras of molecular medicine
UNIFR Rusconi 2003
genomeABC.mov
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Now, let's talk about Somatic Gene Therapy (SGT)
UNIFR Rusconi2003
Chronic treatment
Definition of SGT 'Use genes as
drugs' Correcting disorders by somatic gene
transfer
Acute treatment
Preventive treatment
NFP37 somatic gene therapy www.unifr.ch/nfp37
Hereditary disorders
Acquired disorders
Loss-of-function
Gain-of-function
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The SGT principle is simple Yes,...but the
devil is often in the details
UNIFR Rusconi2003
Gene therapy turns teenage in 2003, buthas it
really grown up?
There are many things that are simple in
principle, like...
1990
First clinical trial of a monogenic disease F.
Anderson Co ADA deficiency
getting a train ticket...
! try this 5 min before departureand with a
group of Chinese tourists in front
...does not work
parking your car...
! try this at noon, any given day in Zuerich or
Geneva ...
2002
Same protocol as Anderson's for ADA gene therapy
(C. Bordignon)
counting votes...
...it works!
! ask Florida's officials ...
gene therapy...
look at progress in 13 years...
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Why 'somatic'?
UNIFR Rusconi2003

• Germ Line Cells the cells (spermatocytes and
  oocytes and their precursors) that upon
  fertilisation can give rise to a descendant
  organism

• Ergo
• transformation of germ line cells is avoided, to
  exclude risk of erratic mutations due to
  insertional mutagenesis

i.e. somatic gene therapy is a treatment aiming
at somatic cells and conse-quently does not lead
to a hereditary transmission of the genetic
alteration

• Somatic Cells all the other cells of the body

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When/where/ may be SGT indicated?
UNIFR Rusconi2003

• No existing cure or treatment
• most monogenic diseases

• Side effects and limitations of protein injection
• interleukin 12 (cancer)-gt toxic effects and
  rapid degradation
• VEGF (ischemias)-gt angiomas
• Factor VIII or IV (hemophilia)-gt insufficient
  basal level

• Ergo
• there are many indications for SGT as stand-alone
  or as complementary therapy

• Complement to conventional
• increase specificity of conventional therapy
  (cancer)
• increase efficacly of conventional therapy
  (hemophilia)

• Life quality burden of patient
• costs of enzyme therapy (ex. ADA)
• burden of daily injections (ex. Insulin)

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SGT's four fundamental questions players
UNIFR Rusconi2003
Efficiency of gene transfer
Specificity of gene transfer
Persistence of gene transfer
Toxicity of gene transfer

• The variables
• which disease?
• which gene?
• which vector?
• which target organ?
• which type of delivery?

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The SGT acrobatics matching vectors / delivery
system / disease
UNIFR Rusconi2003

• Chronic Conditions
• Slow onset of expression acceptable
• Initiation of the treatment weeks/months/years
  before 'point of no return' (ex. cystic
  fibrosis)
• persisting expression of the transgene or
  re-administration required (example hemophilia)
• Usually based on compensation of 'genetic
  loss-of-function' (permanent re-gain of function
  ex. ADA)
• Regulation of gene expression often necessary
  (because of persistence)
• For some diseases even a small of tissue
  transformation is already therapeutic

• Acute Conditions
• Rapid onset of expression necessary
• Initiation of the treatment minutes/hours/days
  before 'point of no return' (ex. brain ischemia)
• persisting expression of the transgene not
  required, occasional re-administration (example
• Usually based on augmentation of resident
  function (transient gain of function ex. VEGF)
• Regulation of gene expression not necessary
  (because of transiency)
• For most diseases even a small of
  transformation is already therapeutic

• Ergo
• many divergent variables must be matched for each
  case
• an advantage for one purpose becomes a
  disadvantage for another (viceversa)

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Pharmacological considerations for DNA transfer
UNIFR Rusconi 2003
Classical Drugs
Protein Drugs
Nucleic Acids

• Mw 20 000- 100 000 Da
• Biologically prepared
• Slower diffusion/action
• Oral delivery not possible
• Cellular delivery - act extracellularly
• Can be delivered as soluble moleculesnm size
• rapidly reversible treatment

• Mw 50- 500 Daltons
• Synthetically prepared
• Rapid diffusion/action
• Oral delivery possible
• Cellular delivery - act at cell surface-
  permeate cell membrane- imported through
  channels
• Can be delivered as soluble moleculesÅngstrom/nm
  size
• rapidly reversible treatment

• Mw N x 1000000 Da
• Biologically prepared
• Slow diffusion
• Oral delivery inconceivable
• Cellular delivery- no membrane translocation -
  no nuclear translocation- no biological import
• Must be delivered as complex carrier
  particles50-200 nm size
• slowly or not reversible

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• Therapy with nucleic acids
• requires particulated formulation
• is much more complex than previous drug
  deliveries
• has a different degree of reversibility (dosage
  problem)

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THREE classes of anatomical gene delivery
UNIFR Rusconi 2003
Ex-vivo
In-vivo topical delivery
In-vivo systemic delivery
Examples - bone marrow - liver cells - skin cells
Examples - brain - muscle - eye - joints - tumors
Examples - intravenous - intra-arterial -
intra-peritoneal
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TWO classes of gene transfer vectors non-viral
viral delivery
UNIFR Rusconi 2003
Non-viral transfer (transfection of plasmids)
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Viral gene transfer (Infection by r-vectors)
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Nuclear envelope barrier! see, Nature
Biotech December 2001
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Transfection versus Infection
UNIFR Rusconi 2003
Transfection
exposed to 106 particles/cell 12 hours
Infection
exposed to 1 particle/cell 30 min

• Ergo
• virally mediated gene transfer is millions of
  times more efficent than nonviral transfer (when
  calculated in terms of transfer/particle)

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Most relevant issues in the two main
'vectorology' sectors (viral versus nonviral)
UNIFR Rusconi2003

• Viral vectors
• Packaging capacity from 4 to 30 kb problem for
  some large genes (ex. dystrophin gene or CFTR
  gene)
• important toxic load ratio infectious/non-infecti
  ous particles from 1/10 to 1/100
• strong immunogenicity capsid and envelope
  proteins, residual viral genes
• contaminants replication-competent viruses (ex.
  wild type revertant viruses)
• Viral amount (titre) obtainable with recombinants
  (ex. 10exp5 poor, 10exp10excellent)
• Complexity of production (existence or not of
  packaging cell systems)
• Emotional problems linked to pathogenicity of
  donor vectors (ex. lentiviruses)

• Nonviral vectors
• Packaging capacity not an issue, even very large
  constructs can be used (example entire loci up to
  150 kb)
• minor toxic load small percentage of non
  relevant adventitious materials
• moderate immunogenicity methylation status of
  DNA (example CpG motifs)
• contaminants adventitious pathogens from poor
  DNA purification (ex endotoxins)
• Amount of DNA molecules is usually not a problem,
  the other components depends on chemical
  synthesis
• No particular complexity, except for specially
  formulated liposomes
• no particular emotional problems linked to the
  nature of the reagents

• Ergo
• problems that must be solved to be suitable for
  clinical treatment and for industrial production
  are different between viral and non-viral vectors
• when ignoring thir low efficiency, nonviral
  vectors appears largely superior

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Ideal properties of a systemically delivered
non-viral formulation
UNIFR Rusconi2003

• Stability
• particle should resist serum inactivation
• particle should be inert to immune inactivation

• Ergo
• several independent problems must be solved for a
  nonviral formulation to be suitable for clinical
  treatment and for industrial production
• most viral vectors include many, if not all those
  properties

• Addressability
• particle should possess a vascular addressing
  signature
• particle should bear a tissue-docking specificity
• DNA construct should include tissue-specific
  regulatory elements

• Efficiency
• cargo should be protected from cytoplasmic
  inactivation (ex. lysosomes)
• cargo should contain nuclear-translocating
  signals
• DNA cargo should include genome-integration
  functions
• DNA element must be guaranteed to function after
  genomic integration (no silencing)

• Other properties
• Particle should not include immunogenic/toxic
  surfaces
• cargo should not encode immunogenic/toxic
  products
• Cargo should include anti-apoptotic functions

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Small parade of popular vectors/methods
UNIFR Rusconi 2003
Naked DNA Liposomes Co. Oligonucleotides
Adenovirus Adeno-associated V. Retrovirus
(incl. HIV)
but remember... "Nobody's perfect "!
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Recombinant Adenoviruses
UNIFR Rusconi 2003

• Approaches
• Generation I
• Generation III
• Hybrid adenos
• Adeno-RV
• Adeno-AAV
• Adeno-Transposase

• Advantages / Limitations
• 8 Kb capacity Generation I gt30 Kb capacity
  Generation IIIAdeno can be grown at very high
  titers,However
• Do not integrate
• Can contain RCAs
• Are toxic /immunogenic

• Examples
• OTC deficiency (clin, ---)
• Cystic Fibrosis (clin, --- )
• Oncolytic viruses (clin, )

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Recombinant adeno-associated-virus (AAV)
UNIFR Rusconi 2003

• Advantages / Limitations
• Persistence in the genome permits long-
• term expression, high titers are easily
• obtained, immunogenicity is very low,
• However the major problem is
• Small capacity (lt4.5 kb) which does not allow to
  accommodate large genes or gene clusters.

Approaches Helper-dependent production Helper
independent production Cis-complementing
vectors Co-infection

• Examples
• Hemophilia A (clin, animal, )
• Gaucher (clin, animal, )
• Brain Ischemia (animal, )
• Cystic fibrosis (animal, /-)

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Recombinant Retroviruses (includes HIV-based)
UUNIFR Rusconi 2003
Approaches Murine Retroviruses VSV-pseudotyped
RV Lentiviruses ! Self-inactivating
RV Combination viruses

• Advantages / Limitations
• 9 Kb capacity integration through
• transposition also in quiescent cells
• (HIV), permit in principle long-term
• treatments, however disturbed by
• Insertional mutagenesis
• Gene silencing
• High mutation rate
• Low titer of production

• Examples
• SCID (IL2R defect, Paris) (clin, )
• Adenosine Deaminase deficiency (clin, !!!)
• Parkinson (preclin, )
• Anti cancer (clin /-)

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Naked / complexed DNA
UNIFR Rusconi 2003
Approaches Naked DNA injection /biolistic Naked
DNA pressure Naked DNA electroporation Liposom
al formulations Combinations

• Advantages / Limitations
• Unlimited size capacity lower
• immunogenicity and lower bio-risk
• of non viral formulations is
• disturbed by
• Low efficiency of gene transfer
• Even lower stable integration

• Examples
• Critical limb Ischemia (clin, )
• Cardiac Ischemia (clin, /-)
• Vaccination (clin, /-)
• Anti restenosis (preclin. /-)

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Oligonucleotides
UNIFR Rusconi 2003
Approaches Antisense Ribozymes/DNAzymes Triple
helix Decoy / competitors Gene-correcting oligos

• Advantages / Limitations
• these procedures may be suitable for
• handling dominant defects
• transient treatments (gene modulation)
• permanent treatments (gene correction)

• Examples
• Anti cancer (clin,preclin., /-)
• Restenosis (clin, )
• Muscular Distrophy (animal, )

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Recap current limitations of popular vectors
UNIFR Rusconi 2003
Adenovirus - no persistence - limited packaging -
toxicity, immunogenicity
Biolistic bombardment or local direct injection -
limited area
Electroporation - limited organ access
Retrovirus (incl. HIV) - limited packaging -
random insertion - unstable genome
Liposomes, gene correction Co. - very
inefficient transfer
General - antibody response - limited packaging -
gene silencing
General - low transfer efficiency - no or little
genomic integration
Solutions - synthetic viruses (Virosomes)
Solutions - improved liposomes with viral
properties (Virosomes)

• Ergo
• the future will see increasing interest in
  viral-like, but artificial particles

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Not all gene therapy approaches are 'random
shooting'
UNIFR Rusconi2003

• Ergo
• genotoxic
• non-genotoxic

• Random integrating vectors
• r-lentiviruses
• r-retroviruses
• r-AAV
• plasmids (low frequency)
• plasmids transposase (eg 'sleeping beauty')

• Specifically integrating vectors
• hybrid vectors (HSV-AAV)
• Phage 31 integrase-based
• designer integrase

• Transient, non integrating vectors
• adenovirus
• plasmid
• RNA virus based
• oligonucleotides (SiRNA, antisense, ribozymes)
• artificial chromosomes

• Gene correction vectors
• chimeroplasts (RNA-DNA chimeric oligos)
• single stranded DNA (homologous recom)

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Which vector for which disease category
UNIFR Rusconi2003
Justifications /Issues
Most suitable vector
Disease Type
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Technologies related to-, but not genuinely
definable as 'gene therapy'
UNIFR Rusconi2003

• Bioactive oligonucleotides
• antisense
• decoy dsDNA
• decoy RNA
• ribozymes DNAzymes
• Si RNA

• Oncolytic viruses
• ONYX-15, ONYX-638 (r-adeno)
• r-HSV
• r-FSV

• Implants of encapsulated cells
• neurotrophic factor producer cell implants
• hormone-producing cells

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'Classical' SGT models and strategies
UNIFR Rusconi2003
Disease
transferred function
Clinical Results

• additional 'popular' and emerging examples
• Morbus Gaucher, Morbus Parkinson, Crigler Njiar,
  OTC deficiency, Duchenne's MD, Restenosis control

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Gene Therapy in the clinic Trials Wordldwide
UNIFR Rusconi2003

• Ergo
• in spite of 13 year- research only less than 1
  of the trials has reached phase III

As of December 2002632 registered
protocols 3472 treated patients
66 phase I 21 phase I-II 11 phase II 0.8
phase II-III 0.7 phase III
21 overall still pending or not yet Initiated
! www.wiley.com/genetherapy
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Gene therapy in Switzerland the 30 projects
financed by the NFP37 programme (1996-2001)
UNIFR Rusconi2003
NFP37 phase A phase B (96-99) (99-01)
Submissions 30 26 Granted 19 18 Total requested
32 Mio 9 Mio Granted 7.6 Mio 6 Mio
DISEASE ORIENTATION Cancer 8 10 Acquired
disorders 2 7 Vector development 5 3
Hereditary disorders 2 4 Infectious diseases
1 2 RESEARCH LEVEL Fundamental 10 7
Preclinical (animal models) 5 9 Clinical phase
I 2 3 Clinical Phase II 0 1 Clinical Phase
III 0 0 Ethical/social aspects 1 1
Nationales Forschungsprogramm 37 NFP37  somatic
gene therapy www.unifr.ch/nfp37

• Please Note
• the NFP37 represented at most 30 of the
  Swiss-based experimentation in SGT during
  1996-2001

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Gene Therapy Clinical and Preclinical Milestones
UNIFR Rusconi2003
1990, 1993, 2000 // ADA deficiency F Anderson, M
Blaese // C Bordignon
1997, 2000, Critical limb ischemia J Isner (
4.11.2001), I Baumgartner, Circulation 1998
1998, Restenosis V Dzau, HGT 1998
1999, Crigler Njiar (animal) C Steer, PNAS 1999
2000, Hemophilia M Kay, K High
2000, SCID A Fischer, Science April 2000
2000, correction Apo E4 (animal model) G.
Dickson, 2000 esgt, 2002 BBA
2000, correction Parkinson (animal model) P
Aebischer, Science, Nov 2000
2001, ONYX oncolytic Viruses D Kirn (Cancer Gene
Ther 9, p 979-86)
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Two major SGT frustration cases
UNIFR Rusconi2003

• Muscular dystrophy (incidence 1 3000 newborn
  males)
• requires persistence of expression
• extremely large gene (14 kb transcript, 2 megaBP
  gene
• unclear whether regulation necessary
• unclear at which point disease is irreversible

• Cystic fibrosis (incidence 1 2500 newborns)
• luminal attempts failed because of anatomical /
  biochemical barrier no receptors, mucus layer
• large gene that requires probably regulation
• requires long term regulation
• unclear at which point disease becomes
  irreversible

• Although genes discovered in the 90ties
• no suitable vector
• no satisfactory delivery method

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The most feared potential side-effects of gene
transfer
UNIFR Rusconi2003

• Immune response to vector
• immune response to new or foreign gene product
• General toxicity of viral vectors
• Adventitious contaminants in recombinant viruses
• Random integration in genome-gt insertional
  mutagenesis (-gt cancer risk)
• Contamination of germ line cells

• Random integration in genome-gt insertional
  mutagenesis (-gt cancer risk)

• Ergo
• Most side effects are still related to the rather
  primitive state of the vectorology/delivery

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Three (four) bitter lessons, but only one
treatment-related death so far
UNIFR Rusconi2003
NY May 5, 1995, R. Crystal in a trial with
adenovirus mediated gene transfer to treat cystic
fibrosis (lung) one patient developed a mild
pneumonia-like condition and recovered in two
weeks. The trial interrupted and many others on
hold.
UPenn, Sept. 19, 1999, J. Wilson in a trial
with adenovirus mediated gene transfer to treat
OTC deficiency (liver) one patient (Jesse
Gelsinger) died of a severe septic shock. Many
trials were put on hold for several months
(years).
Paris, Oct 2, 2002, A Fischer in a trial with
retrovirus mediated gene transfer to treat SCID
(bone marrow) one patient developed a
leukemia-like condition. The trial has been
suspended to clarify the issue of insertional
mutagenesis, and some trials in US and Germany
have been put on hold.
Paris, Jan 14, 2003, A Fischer a second patient
of the cohort of 9 comes up with a similar
disease than the one reported in october 2002. 30
trials in USA are temporarily suspended
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Public perception problems
UNIFR Rusconi2003

• Negative perception of manipulative genetics
• general aversion of genetic manipulation
• fear of catastrophic scenarios

• Confusion with other gene-based and
  non-gene-based technologies
• stem cell technology
• human cloning procedures
• genetically modified food

• Deception after excessive promises
• hopes reinforced by media spectacularisation and
  over-simplification
• deception after non-complied deadline

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Other factors that have negatively influenced
the public perception and progress of gene
therapy
UNIFR Rusconi2003

• Naive statements by some good-willing scientists
  in the early 90ties
• Not-so-naive statements by not-so-naive
  scientists in search of fame
• Huge amount of money that flowed into the
  research and development that attracted many
  incompetent researchers.
• Concomitance with stock-market euphoria (little
  attention to realism)
• Reckless statements or misreporting by greedy
  scientists or company managers to increase the
  value of their stock options (memorandum by the
  ASGT on conflict of interest 2000, www.asgt..org)
• Tendency by the media to spectacularise good news
  and/or bad news

• Ergo
• An explosive cocktail, just like for sports or
  arts,...
• the field tends to degenerate as soon as huge
  amounts of money are involved and when the mass
  media become interested in it.

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Ups and Downs of Gene Therapy a true roller
coaster ride!
UNIFR Rusconi2003
A. Fischer M. Kay
lentivectors in clinics?
R. Crystal
V.Dzau
Adeno I
C Bordignon
J. Isner
ADA
AAV germline in mice?
NIH Motulski report
Adeno III

• Ergo
• whenever a reasonable cruise speed was achieved,
  a major adverse event has brought us back square
  one

Lentivectors in pre-clinic
Adverse events in Paris
J. Wilson J. Gelsinger
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Genes, cells, tissue transplants...some people
fear possible negative developments
UNIFR Rusconi2003
Amelioration instead of therapy?
aa beauty woman.mov
Too High-tech too expensive
robot woman.mov2
Bioweapons?
military biolabs1.mov
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Somatic Gene Therapy is facing fierce competition
UNIFR Rusconi2003

• 1. Cell Therapy (Stem cells (SC))
• identified in many tissues
• cell transfer could be combined with gene
  transfer
• there would be no anatomical barriers for gene
  transfer
• Selection /amplification of desired transformants
• Current limitations of SC
• Lack of control on differentiation and
  trans-determination
• Difficulties in complex organ-reconstruction
• Future of SC
• Increasing number of SC types will be
  characterised
• culturing conditions will be perfectioned
• May replace in vivo gene transfer for treatment
  of chronic conditions?

• 2. Breakthroughs from the small/medium molecules
• STI571 (Glivec)
• anti HER2 (Herceptin)
• Si RNA?
• ...

• 3. Challengers from the biomechanics world
• bone reconstruction
• intelligent protheses (stents)
• micropumps
• artificial organs

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Conclusions
UNIFR Rusconi2003

• Fundamentally
• a gene encodes usually more than one function
• The therapeutic gene transfer in somatic cells
  must cope with efficiency, specificity,
  persistence and toxicity
• many genes with potential therapeutic value have
  been identified, and essentially all types of
  diseases can be treated by gene transfer

• Vectors and models
• There is the choice of a certain number of viral
  and non viral vectors, none of them being
  generally applicable
• viral vectors have the advantage of efficiency
  and nonviral vector the advantage of lower
  toxicity/danger.
• viral vectors have the disadvantage of limited
  packaging and some toxicity, while nonviral
  vector have the major disadvantage of low
  efficiency of transfer

• Clinically
• over 600 trials and 3500 patients in 12 years
• only a handful of trials is now reaching phase
  III
• Progress further slowed down by periodical
  pitfalls

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Perspectives
UNIFR Rusconi2003

• Fundamental level vectorology
• the better understanding of gene interactions and
  networking (functional genomics) could improve
  the utilisation of gene-based or gene targeted
  strategies
• novel paradigms can become available (Si RNA, PNA
  triplex etc...)
• specifically integrating gene constructs or
  artificial chromosomes becoime more realistic

• Preclinically
• scaling up to larger animal models (dog and
  monkey) permits better appreciation of dosage
  requirements
• new transgenic models may give improved
  similarities to human diseases

• Clinically
• Use of recombinant lentiviruses may be imminent
• Increase of Phase III procedures over the next 5
  years
• First therapeutical applications may be
  registered within 3-5 years
• challenge by other emerging therapies

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...Thanks !
UNIFR Rusconi2003

ECPM
My collaborators at UNIFR
Swiss National Research Foundation
Thank you all for the attention, and... if you
are too shy to ask send an e-mail
to sandro.rusconi_at_unifr.ch or visit www.unifr.ch
/nfp37
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