TS Meeting Lima_Peru Oncology Congress January 2010 Scientific ...

lunchlexicographerBiotechnology

Dec 1, 2012 (4 years and 10 months ago)

230 views

Biotech Pharmaceuticals -Scientific Aspects and Regulatory ConsiderationsDr. Thomas Schreitmüller
Table of content
BiotechPharmaceuticals: Wheredo westand today
Propertiesof Proteins
MonoclonalAntibodies A Perspective on BiosimilarMonoclonal Antibodies Immunogenicity
Conclusions
Biotech Pharmaceuticals –Where do we stand today?
•Biotechnology has produced medical treatment for hitherto serious
incurable diseases. About 250 biotech drugs approved for 380
indications.
•More than 300 biotech products are in clinical trials targeting more
than 200 diseases, including cancer treatment (40%), auto-immune
diseases etc.
•Biotech industry expanded rapidly in 1990’s. Global biotech sales
grew 12.5% in 2007. Today, more than $70B business worldwide.
•22 biotech products generated sales more than $1B in 2007
compared with just 6 in 2002. 50% of new drugs are bio drugs.
3
Source: IMS 2008
Table of content
BiotechPharmaceuticals: Wheredo westand today
Propertiesof Proteins
MonoclonalAntibodies A Perspective on BiosimilarMonoclonal Antibodies Immunogenicity
Conclusions
ProteinsBasic Structures
ProteinsMolecularSizeand 3-D Structure
M. Clark,
http://www-immuno.
path. cam.ac.uk/~mrc7/
Antibody (IgG)
molecule
Interferon-α
Aspirin

May not be enough to have the correct protein sequence
-nucleic acid sequence can affect translation, thereby folding and activity
-“A Silent Polymorphism in the MDR1 Gene Changes Substrate Specificity”.
Kimchi-Safaty, Gottesmanet al.(2007) Science 315, 525-528.
ProteinsHigherOrder StructureIssues
Proteins 3D structures are in dynamic vibrations in normal
conditions; an alteration of physiological parameters (pH,
temperature, solvent, etc.) may denaturateits active structure.
ProteinsStructuralFlexibility
www.nurseminerva.co.uk/images/haem2
bowers.chem.ucsb.edu/theory_analysis/mm/PES
Proteins functions requiring conformational changes.
ProteinsFunctional Flexibility
Microheterogeneity: the t-PA Example
COOH
Variable N-linked
carbohydrate
sidechains
Additional O-glycosylation
Proteolysisat Arg-X
N-terminalsequence
lengthvariation
NH2
Deamidationof Asn
residues
Oxidation of Cysor
Met residues
Possible Sources of Heterogeneity
TissuePlasminogenActivator(t-PA): A 527-aminoacidprotein
with17 S-S bridgesand 3 glycosylation sites
Single-chain
and two-chain
forms
Total possiblevariants:
1.09 x 10
9
Protein Microheterogeneity
Small Molecule
Drug
Protein
Drug
•Biotech products are very complex, sensitive,
heterogeniousmixtures of protein molecules.
•Each molecular entity of that mixture is
characterized by specific physical, chemical and
biological properties.
•Any change in the composition of that mixture is potentially going to affect patients safety and
chance of cure.
Biotech products
Table of content
BiotechPharmaceuticals: Wheredo westand today
Propertiesof Proteins
MonoclonalAntibodies
A perspective on BiosimilarMonoclonal Antibodies Immunogenicity
Conclusions
TheStructureof MAbsishighlycomplex
Not all possible variants are described. For example, there are fucosylation
variants in glycosylationthat were not counted. If one assumes these variants
are independent and considers combinations, each half-antibody has
2x6x4x4x5x5x2=9600 possible states.
If one assumes both halves of the antibody are independent, there are (9600)
2

10
8
possible states.
Source: Kozlowski, S. & Swann, P. (2006) Adv. Drug Delivery Revs58, 707-722
The importance and associated Effects of glycosilation
non-human/antigenic
(Cooper, Xenotransplantation1998)
α(1-3)-Gal
Enhanced ADCC
(Okazaki et al., J. Mol. Biol. 2004)
absence of core
Fucose
prevents core fucosylation￿enhanced ADCC
(Umañaet al., Nat. Biotech. 1999)
bisecting GlcNAc
Placental transport
(Kibeet al., J. Clin. Biochem. Nutr. 1996)
Galactose
Suppression of ADCC(anti-inflammatory activity) (Kaneko
et al., Science 2006)
Sialicacid
Ligandfor Mannose Binding Protein ￿complement
activation (Malhotraet al., Nat. Med. 1995)
GlcNAc/ Mannose
a1-3
Source: H. Kettenberger, Roche
Immune effector function
0
20406080
100120
01020304050
antibody conc. [ng/ml]
cell lysis in %
glycoengineered antibody
wildtype antibody
glycoengineered negative
control antibody

(100% fucosylated)
(only26% fucosylated)
Lowering the
fucosecontent
e.g. by glycoengineeringleads to
higher affinity
of the
antibody Fcpart to Fcreceptors on immune effectorcells. Immune effectorcells are
recruited and activated more efficiently. Antibody-dependent cellular cytotoxicity
(ADCC) is strongly increased (depending on tzherecruited effectorcell type).
This is highly relevant for the potency and safety profile of some antibodies.
Data fromRoche Penzberg
LoweringtheFucoseContentincreasesADCC
0
1
2
3
4
5
01234567
% Non-Fucosylated IgG
Relative ADCC(in-vitro)
Even very
small differences in
fucosylation
may have significant
effects on in vitroADCC.
R. Garnick(2008) Biogenerics2008 Conference
TheGlycopatterndependson theHost Celland on theFermentation Conditions
Level of a-fucoseduring10-l-labscalefermentations
Run 1 #1
0%
20%40%60%80%
100%
56789
10
11
12
13
14
15
% non-fuc
% complex
% bisected
Clone1, 1 X YClone165, 1 X Y
Run 2.1
0%
20%40%60%80%
100%
579
11
13
15
17
% non-fuc
% complex
% bisected
Run 2.2
0%
20%40%60%80%
100%
579
11
13
15
17
Run 2 #1
0%
20%40%60%80%
100%
56789
10
11
12
13
14
15
Source: Roche Penzberg
Table of content
BiotechPharmaceuticals: Wheredo westand today
Propertiesof Proteins
MonoclonalAntibodies
A Perspective on BiosimilarMonoclonal Antibodies
Immunogenicity
Conclusions
22
TheMode of Action of mAbsiscomplex
and mayinvolveContributionsfrommultiple Mechanisms
Inhibition of Signal TransductionorReceptorActivation
•Inhibition of LigandBinding
(Example: Cetuximab)
•Inductionof ReceptorInternalization
(Example: IGF-1R-Abs
)
•Inhibition of ReceptorDimerization
(Example: Pertuzumab)
•Inhibition of ReceptorShedding
(Example: Trastuzumab)
Inductionof Apoptosis
(Example: Rituximab)
Activationof Effector
Mechanisms
Complement
Activation(CDC
)
(Example: Rituximab)
BlockingLigandBinding
(Example: Bevacizumab)
Targetingof Toxins
(Example: T-DM1)
EGFR
VEGF
-R
CD20
CD20
CD20
HER2
Activationof T-Cells
(Example: Catumaxomab)
CD3
HER
2
HER2
T-Cell
Antibody-dependentcellular
Cytotoxicity(ADCC)
(Example: Rituximab)
NK-Cell
C1q
TumorC
ell
Modifiedfrom: Hasmann, M. et al. (2009) ChiuZ, submitted
Thein-vivonetcontributionof different modesof actiondescribedforonemAbis
oftenincompletelyunderstoodand mayalso bedifferent in different indications.
mABBiosimilarsTheCHMPBMWPChair‘sViewhas beenpublishedrecently
Schneider, Christian K. & Kalinke, Ulrich, Toward biosimilarmonoclonal antibodies (2008)
Nature Biotechnol. 26
, 985-990
mAbBiosimilars-Issuesand Conclusions
…it is clear why the 'generic' approach is not applicable to biotechnological products—a fact that is all
the more relevant for mAbs, which are
considerably more complex than currently developed
biosimilars,
such as human growth hormone, insulin or erythropoietin.

glycosylation patterns are likely to be among the most crucial issues
for biosimilar mAb
development, because these modifications can influence binding, immunogenicity and effector activity
of a mAb molecule.
For mAbs, this [i.e., extrapolation of indications] can be a particular challenge because their
mechanism of action is usually complex and in many cases only partially understood.
Mechanism of action relates not only to binding of the Fab part of the mAb to its epitope (and all
associated signaling events that are subsequently triggered or inhibited), but also to the complex
interaction of the Fc part with the Fc receptor system (effectorfunction).
Extrapolating from efficacy
in one indication (e.g., psoriasis) efficacy in another indication (e.g., rheumatoid arthritis) can
thus be particularly challenging for a biosimilar mAb.
Another important consideration is the design of the clinical comparative trial. An equivalence study to
demonstrate biosimilarity against a reference mAb might be expected to require a large number of
patients, and might thus be by
far more extensive than the pivotal trial for a stand-alone
development.
As comparative trials to establish similarity of efficacy and safety can require a large number of
patients,
it might well turn out for certain mAbs that the biosimilar approach is simply not
feasible.
Source: Schneider, C. K. & Kalinke, U., Toward biosimilarmonoclonal antibodies (2008) Nature Biotechnol. 26
, 985-990
A variety of Functionalities are associated with Rituximab!
EMEAworkshop on Monoclonal Antibodies–2 July 2009
Completely different dose schedules for Rituximab
across different indications!
EMEAworkshop on Monoclonal Antibodies–2 July 2009
Mode of Action in vivo of Rituximabis poorly
understood!
EMEAworkshop on Monoclonal Antibodies–2 July 2009
Completely different dose response relation of
Rituximabacross different indications!
EMEAworkshop on Monoclonal Antibodies–2 July 2009
Very specific clinical outcomes for sub-populations in
different indications for Rituximab!
EMEAworkshop on Monoclonal Antibodies–2 July 2009
For Rituximaba simple extrapolation of indications
puts patients at risk!
EMEAworkshop on Monoclonal Antibodies–2 July 2009
Table of content
BiotechPharmaceuticals: Wheredo westand today
Propertiesof Proteins
MonoclonalAntibodies A Perspective on BiosimilarMonoclonal Antibodies
Immunogenicity
Conclusions
•Most biopharmaceuticals induce antibodies
•The consequences of immunogenicity may be manageable (e.g. loss or
enhancement of efficacy, general immune effects), but can be severe
(e.g., neutralization of endogenous protein)
•This is a key safety issue for biosimilars
•Immunogenicity can only be revealed through clinical trials
Neutralising antibodies
can inhibit biological activity
Antibodies can impair
endogenous protein function
Protein drug
Antibody
Antibody
Patient protein
Immunogenicity
Breakdown of Self Tolerance
Immunogenicity
Low quality,
aggregated product
B cell
B cell
B cells produce binding antibodies against
therapeutic andendogenous protein
Immune tolerance
High quality,
soluble product
Endogenous proteinTherapeuticprotein
B cell
Therapeutic protein aggregates
Antibody
B cells not activated
Factorscontributingto Immunogenicity
0
200400600800
100012001400160018002000
012345678
IFNneutralizingunits
Time (months)
Antigenicityof different IFN alpha-2a Products
A (n = 190)
B (n = 86)
C (n = 110)
D (n = 81)
E (n = 74)
H. Schellekens(2005) FDA/DIA Workshop on Follow-onProtein Products
A. DePaoliset al CentocorInc., 2005
EPOand PRCA
Assessmentof Immunogenicity
H. Schellekens(2003) IBCConferenceon MultisourceBiologicals
•Current
analytical methodscannot predict
immunogenicity
•The immune system can detect alterations in proteins missed by
analytical methods
•The clinical consequences are mostly benign, but may be severe

Only clinical trials are decisive to reveal immunogenicity
•Comparison of immunogenicity can only be made in comparative
clinical trials (no comparison based on „historical data“possible)
Biosimilarsin EUInterchangeability/Substitution: The English Way
Epoetinalfa: Binocrit®, EpoetinalfaHexal®, Abseamed®
Vorläufige Beendigung einer klinischen Studie zur subkutanen
Anwendung des Epoetinsbei Patienten mit renalerAnämie
Aktualisiert: 05.08.2009Erstellt: 05.08.2009
Die Firma Sandoz hat Anfang Juni 2009 die Fortführung einer klinischen Studie zur Sicherheit der subkutanen
Gabe eines EpoetinalfaNachfolgepräparates (HX575) an Patienten mit renalerAnämie vorläufig beendet. Anlass
war das Auftreten einer Aplasieder roten Blutkörperchen (pure red cellaplasie; PRCA) bei einem deutschen
Studienpatienten sowie der Nachweis von neutralisierenden Antikörpern gegen Erythropoietinbei einem
Studienteilnehmer aus Russland.
Nach dem Abbruch der klinischen Studie weist das BfArMausdrücklich darauf hin, dass Epoetinalfa
Hexal®, Binocrit®und Aseamed®bei renalerAnämie ausschließlich zur intravenösen Anwendung
zugelassen sind.
In der randomisierten, kontrollierten, doppelt-blinden Multizenterstudiesollten die Sicherheit und die
Immunogenitätvon subkutan angewendetem EpoetinalfaHexal®mit Erypro/Eprex®, für das die ursprüngliche
Zulassung erteilt wurde, in der Behandlung der Anämie bei Patienten mit chronischer Niereninsuffizienz untersucht
werden. Die klinische Studie wurde durchgeführt, da vor der Zulassung des EpoetinalfaNachfolgepräparates der
Nachweis der sicheren Anwendung bei der subkutanen Applikation nicht erbracht werden konnte und es somit für
die subkutane Anwendung bei renalerAnämie nicht zugelassen ist.
http://www.bfarm.de/cln_012/nn_421158/DE/Pharmakovigilanz/risikoinfo/epo.html__nnn=true
Biosimilarsin EU
Epoetinalfa: Binocrit®, EpoetinalfaHexal®, Abseamed®
•Aone year safety study involving 300 patients suffering from chronic kidney
disease about to embark on dialysis, comparing EPOHexalvs. Johnson & Johnson’s
Erypo, has been suspended; this study was designed to assess the safety of sub-
cutaneous, rather than intravenous, EPOalfaadministration
•On 5 Aug 2009, Germany’s BfArM(Bundesinstitut für Arzneimittel und
Medizinprodukte) confirmed that the trial was suspended due to safety concerns,
specifically a case of pure red cell aplasia(PRCA) in a patient enrolled in a study in
Germany, and a case of EPOneutralizing antibodies in a patient enrolled in a study
in Russia
•In the statement, BfArMcommented that “…after termination of this study, BfArM
explicitly states that EpoAlfa Hexal, Binocritand Abseamedshould only be
administered via the intravenous route when prescribed for renalanemia”
Table of content
BiotechPharmaceuticals: Wheredo westand today
Propertiesof Proteins
MonoclonalAntibodies A Perspective on BiosimilarMonoclonal Antibodies Immunogenicity
Conclusions
Global consolidated conclusions of all serious
stakeholders on biosimilars
•It is impossible to characterize the critical quality attributes of biotech products
completely by physico-chemical analysis.
•Comprehensive prediction of the impact of the expected structural differences on
clinical safety (e.g. immunogenicity) and efficacy is not possible.
•The in vivoMode of Action of many proteins is often complex involving
contributions from multiple mechanisms potentially different in different indications.
•Relevant, comprehensive and head to head comparative pre-clinical and clinical
data will be required for the approval of biosimilarpharmaceuticals.
•Extrapolation of indications will not be possible in many casesand additional
clinical data for additional indication will be required.
•NRA’s are called to set up appropriate regulatory oversight determining a suitable
regulatory framework for licensing biosimilars
Biosimilarsin LA
Thank You Thank You Thank You Thank You