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Non-Clinical Drug Development. Chris H. Takimoto, MD, PhD Institute for Drug Development San Antonio Cancer Institute University of Texas Health Science Center San Antonio, TX. Drug Development. Drug discovery & screening Non-clinical development Animal scale up Phase I studies - PowerPoint PPT Presentation
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Non-Clinical Drug Development
Chris H. Takimoto, MD, PhD
Institute for Drug DevelopmentSan Antonio Cancer Institute
University of Texas Health Science CenterSan Antonio, TX
Drug Development
• Drug discovery & screening• Non-clinical development• Animal scale up• Phase I studies• Phase II studies• Phase III studies
Specific examples from anticancer drug development
Overview of Anticancer Drug Development
IND NDAChemical Synthesis and Formulation Development
Animal Models for Efficacy
Assay Development
Animal PK and PD
Dose Escalation and Initial PK
Proof of Concept and Dose Finding
Large Efficacy Trials with PK Screen
PHASE I PHASE II PHASE IIIPre-Clinical Development Clinical Development
PK/PD Studies in Special Populations
Goals of Non-Clinical Testing of Small Molecule Drugs and Biologicals
• To characterize potential adverse drug effects– Define end organ toxicities– Define reversibility of toxicity
• To characterize pharmacokinetic profile• To characterize beneficial pharmacodynamic
effects– Proof of principle
• To guide safe use in human clinical studies– To determine a safe & reasonable starting dose– Provide monitoring guidelines for the clinical study
• Provide sufficient data to conclude that patients are not exposed to unreasonable risks– Potential for benefit must also exist
Oncology drug development is changing in the new era of targeted cancer therapies
Conventional Wisdom in the New Age of Modern Drug Development
• Targeted therapies are unique and distinct from classic cytotoxic chemotherapies– Classical chemotherapy = poisons
• All new agents entering the clinical have well defined molecular targets
• Conventional clinical study designs are outdated, outmoded, and poorly-suited to develop targeted therapies
• Biomarkers rule!
What are Targeted Therapies?The NCI’s Definition
• From the NCI’s internet fact sheet – Targeted cancer therapies use drugs that block
the growth and spread of cancer. – They interfere with specific molecules involved
in carcinogenesis … and tumor growth. – Because scientists call these molecules
“molecular targets,” these therapies are sometimes called “molecularly-targeted therapies.”
– By focusing on molecular and cellular changes that are specific to cancer, targeted cancer therapies may be more effective than current treatments and less harmful to normal cells.
(http://www.cancer.gov/cancertopics/factsheet/Therapy/targeted)(http://www.cancer.gov/cancertopics/factsheet/Therapy/targeted)
Poster Child for Targeted Therapies
• Prototypical targeted agent is imatinib• A selective inhibitor of BCR-Abl tyrosine
kinase in CML or c-Kit in GIST
Imatinib (Gleevec™)Imatinib (Gleevec™)N
N
NHN
HN
N
N
O CH3SO3H
Imatinib (Gleevec™)
Chronic Myelogenous Leukemia and the Ph Chromosome
• Abnormal Philadelphia (Ph) chromosome identified in most patients with chronic myelogenous leukemia (CML)– Identified in over 90% of CML, 20% of adult ALL and 5%
of pediatric ALL patients• Piece of chromosome 9 is abnormally linked to
chromosome 22– 9:22 translocation
• c-Abl, the cellular homologue of the transforming retrovirus oncogene (v-Abl), is located on chromosome 9– Activation of c-Abl signals the cell to proliferate and
grow
Targeted Therapy with Imatinib
• Imatinib is a potent inhibitor of the BCR-Abl and the c-Kit tyrosine kinases
• Generates marked growth inhibition of CML cells and Gastrointestinal Stromal Cell Tumors (GIST)
• Early Phase I data in CML– Hematological response in 98% and
cytogenetic remissions in 13% of patients treated in Phase I
• Substantial single agent activity in GIST tumors
Targeted Therapies Targeted Therapies & Preclinical Development& Preclinical Development
(adapted from Paoletti 2005)(adapted from Paoletti 2005)
Characteristic Cytotoxic Agents Targeted Agents
Discovery Cell based, empirical Receptor based screen, rationale
Mechanism Often unknown Basis for screening
Pharmacological Effect Cytotoxic Cytostatic
Specificity Non-selective Selective
Dose and schedule Pulsed, cyclical at MTD
Continuous, at tolerable dose
Targeted Therapies & Phase I Trials
(adapted from Paoletti 2005)
Characteristic Cytotoxic Agents Targeted Agents
Objectives PK, MTD Optimal biological dose (OBD), PK, PK-PD
Disease All types All types or target bearing
Dose Toxicity-guided escalation
Biomarker-guided escalation
Endpoints Toxicity, MTD, PK Target inhibition, OBD, PK
Design Dose escalation in small cohorts
Dose escalation to target inhibition
Components of Non-Clinical Drug Development
1. In vitro studies: Cell lines, cell-free systems (drug screening)
2. Drug formulation 3. Chemistry, Manufacturing, and
Controls: Drug supply & quality4. In vivo efficacy studies: Animal
models and proof of principle5. Non-clinical safety studies
In Vitro Study Goals: Define the Drug’s Pharmacology
• Molecular mechanism of action and specific drug targets
• Molecular pharmacology• Determinants of response • Intracellular pharmacodynamics• Mechanisms of drug resistance
In Vitro Study Systems
• Cell-free assay for specific molecular effects– Enzyme inhibition, receptor blockade,
etc.• Yeast-based screening in genetically
defined target• Mammalian cell lines: (murine,
human, etc.)
Preclinical PharmacologyIn Vitro Studies of Cancer Agents (1)• Define anticancer effects
– Growth inhibition, differentiation, apoptosis, etc
• Impact on defined biochemical and molecular pathways– RNA, DNA and protein biosynthesis, signaling
kinases, etc• Spectrum of antitumor activity
– Human tumor cell lines
Preclinical PharmacologyIn Vitro Studies of Cancer Agents (2)• Cellular uptake and membrane transport
– MDR, MRP, etc• Mechanisms of resistance• In vitro drug metabolism
– P450 isoenzymes• Effects on hERG channels (prolonged QT
interval risk)• Preliminary protein binding studies
Components of Non-Clinical Drug Development
1. In vitro studies: Cell lines, cell-free systems (drug screening)
2. Drug formulation 3. Chemistry, Manufacturing, and
Controls: Drug supply & quality4. In vivo efficacy studies: Animal
models and proof of principle5. Non-clinical safety studies
Drug Supply and Formulation
• Drug supply: bulk chemical synthesis, natural product isolation, etc.
• Good Manufacturing Practice (GMP) guidelines for pharmaceutical product manufacturing
• Formulation for clinical delivery of drug: vehicles for intravenous or other routes of administration
Drug Supply Issues
• Paclitaxel source from the bark and wood of the Pacific Yew tree
• Early drug supply limited the amount available for initial clinical trials
• Newer semisynthetic production from the needles of the Yew tree (renewable)
Drug Formulation Issues
• Poor water solubility of natural products
• Paclitaxel formulation in Cremophore EL™ (increased toxicity?)
• Camptothecin derivatives formulated in a dimethylacetamide, polyethylene glycol and phosphoric acid vehicle– Later formulated as a lipid colloidal dispersion
Components of Non-Clinical Drug Development
1. In vitro studies: Cell lines, cell-free systems (drug screening)
2. Drug formulation 3. Chemistry, Manufacturing, and
Controls: Drug supply & quality4. In vivo efficacy studies: Animal
models and proof of principle5. Non-clinical safety studies
In Vivo Study Goals:Animal Models
• Efficacy: Proof of therapeutic principle
• Toxicology: Toxicity profile• Practical Issues:
– Animal pharmacokinetics and pharmacodynamics
– Starting dose and schedule for clinical trials
Animal ModelsProof of Principle
• Animal screening is too expensive for routine use
• Efficacy in animal models of specific disease states occurs after in vitro studies
• Evaluation of therapeutic index– Toxicity versus efficacy
Ideal Animal Model• Validity• Selectivity• Predictability• Reproducibility
“There is no perfect tumor model”
Endostatin: An Endogenous Inhibitor of Angiogenesis and Tumor Growth
O'Reilly et al, Cell 88:277-285 (1997)
Animal Models in Cancer• Spontaneous tumors
– Idiopathic– Carcinogen-induced– Transgenic/gene knockout animals: p53, RB,
etc• Transplanted tumors
– Animal tumors: Lewis lung, S180 sarcoma, etc– Human tumor xenografts: human tumor lines
implanted in immunodeficient mice (current NCI standard in vivo efficacy testing system)
– Human tumors growing in vivo in implantable hollow fibers
Human Tumor Xenografts
• Athymic “nude”mice developed in 1960’s• Mutation in nu gene on chromosome 11• Phenotype: retarded growth, low fertility,
no fur, immunocompromised– Lack thymus gland, T-cell immunity
• First human tumor xenograft of colon adenocarcinoma by Rygaard & Poulson, 1969
Athymic Nude Mice
Murine Xenograft Sites
• Subcutaneous tumor (NCI method of choice) with IP drug administration
• Intraperitoneal• Intracranial• Intrasplenic• Renal subcapsule• Site-specific (orthotopic) organ
inoculation
Xenograft Study Endpoints
• Toxicity Endpoints:– Drug related death– Net animal weight loss
• Efficacy Endpoints– Clonogenic assay– Tumor growth assay (corrected for tumor
doubling time)– Treated/control survival ratio– Tumor weight change
Xenograft Tumor Weight Change
• Tumor weight change ratio (used by the NCI in xenograft evaluation)
• Defined as: treated/control x 100%• Tumor weight in mg = (a x b2)/2
– a = tumor length– b = tumor width
• T/C < 40-50% is considered significant
Xenograft Advantages
• Many different human tumor cell lines transplantable
• Wide representation of most human solid tumors
• Allows for evaluation of therapeutic index• Good correlation with drug regimens
active in human lung, colon, breast, and melanoma cancers
Xenograft Disadvantages• Brain tumors difficult to model• Different biological behavior, metastases rare
– Survival not an ideal endpoint: death from bulk of tumor, not invasion
• Shorter doubling times than original growth in human
• Less necrosis, better blood supply• Difficult to maintain animals due to infection risks• Host directed therapies (angiogenesis, immune
modulation) may not be applicable– Human vs. murine effects
Other Animal Models
• Orthotopic animal models: Tumor cell implantation in target organ– Metastatic disease models
• Transgenic Animal Models– P53 or other tumor suppressor gene
knockout animals– Endogenous tumor cell development– May be of high value for mAb therapies
Non-Clinical Efficacy TestingThe FDA Perspective
(J. Leighton, FDA ODAC Meeting, March 13, 2006)• Pharmacological activity assessed by models of
disease are generally of low relevance to safety (IND) and efficacy (NDA) decisions– Efficacy in vivo and in vitro from non-clinical studies may
not dependably predict clinical efficacy• Heterogeneity of disease• Interspecies differences in ADME• Role of immune system
• Pharmacology studies are useful for:– Assessing an appropriate schedule (daily, weekly, q3wks)– Justification for a drug combination– Understanding effect at a molecular target
• Examine receptor specificity• Identifying and evaluating biomarkers
Components of Non-Clinical Drug Development
1. In vitro studies: Cell lines, cell-free systems (drug screening)
2. Drug formulation 3. Chemistry, Manufacturing, and
Controls: Drug supply & quality4. In vivo efficacy studies: Animal
models and proof of principle5. Non-clinical safety studies
Non-Clinical Safety Studies
• Safety pharmacology• Toxicokinetics & pharmacokinetic
studies• Single dose toxicity studies• Repeated dose toxicity studies
Safety Pharmacology• Assessment of drug on vital functions• Examples:
– Cardiovascular: heart rate, BP, ECG, QT interval
– Central nervous system: locomotor activity, coordination, proconvulsive effects, analgesic effects
– Respiratory system: respiratory rate, tidal and minute volumes
• Should complete prior to FIH studies• May be separate or a component of
toxicity studies
Pharmacokinetic & Toxicokinetic Studies
• Analytic assay development and testing
• Preclinical PK/PD efficacy and toxicity relationships
• Initial drug formulation testing• Testing of different schedules and
routes of administration• Animal ADME
Non-Clinical Toxicology Studies• GLP Toxicology is expected• Use the clinical schedule, route, and formulation• Single dose acute toxicity studies required in 2
mammalian species prior to FIH studies– Classically rat and dog for small molecules– Non-human primates for biologicals
• Repeat dose toxicology required for anticipated duration of clinical use for most non-oncology agents– 3 mo. toxicology for ≤ 3 mo. clinical study
• Recommendations for agents used in the treatment of advanced cancer differs
Expected Toxicology Testing for Phase I Oncology Drug Studies
(J. Leighton, FDA ODAC Meeting, March 13, 2006)
Clinical Schedule Preclinical study schedule *
Every 21 d Single dose study
Every 14 d 2 doses, 14 d apart
Weekly x 3, week off Weekly x 3
Daily x 5, break Daily x 5
Continuous daily Daily for 28 days
* Study schedule does not include a a recovery period
-- 28 day toxicology is generally sufficient for DRUG trials extending beyond 28 days
Non-Clinical Toxicology Studies For Oncology Drug Combinations• May not be necessary for testing in
advanced cancer patients• May exclude if:
– No PK, PD, or metabolic interactions anticipated
– Drugs are not packaged as a combination
– All components well studied individually
Single Dose Toxicity Studies
• Dose escalation study may be an alternative to a single dose design– Dose range should include maximally
tolerated dose (MTD) and no adverse effect level (NOAEL)
• Standard design– Early sacrifice at 24 to 48 hr and after 14
days
Repeated Dose Toxicity Studies
• Duration of repeated dose studies related to duration of anticipated clinical use– Use same schedule and duration– Typically 14-28 days– Should include recovery group
• Use can support repeat dose clinical studies
Non-Clinical Toxicology Ongoing Endpoints
• Ongoing– Clinical signs, behavior– Body weights and food consumption– Clinical pathology (in larger species)
• Hematology• Chemistry panels
– Toxicokinetics• End of Study
– Macroscopic changes at necropsy– Organ weights– Histopathology of all organs
Other Toxicology Studies
• Local tolerance studies– If warranted by route of administration
• Genotoxicity studies• Reproductive Toxicity studies• Carcinogenicity studies
Genotoxicity studies• General
– Normally done prior to FIH studies, but not required prior to phase I studies in oncology patients
– Standard battery of genotoxicity tests required prior to initiation of phase II
• Specific genotoxicity studies– In vitro bacterial reverse mutation assays: Ames test,
point mutation test– In vitro chromosome damage tests in mammalian cells:
metaphase cell analysis, murine lymphoma gene mutation assays
– In vivo chromosomal damage assays: rodent micronucleus tests
Reproductive Toxicity Studies• Men
– May include in Phase I/II after relevant repeated dose toxicity studies
– Male fertility study should be completed prior to initiation of Phase III
• Women not of childbearing potential– May include in clinical trials after relevant repeated dose
toxicity studies• Women of childbearing potential
– May include in carefully monitored early studies with precautions
– Fertility and embryo-fetal toxicity studies should be completed prior to entry of women into phase III trials
• Pregnant women– All reproductive toxicity and genotoxicity studies must be
completed prior to entry of these women in trials
Carcinogenicity studies
• Usually not needed prior to clinical trial initiation
• Not needed in advanced cancer indications
Preclinical ToxicologyGoals
• Estimate a “safe” starting dose for phase I studies
• Determine the toxicity profile for acute and chronic administration
• NCI guidelines recommend single dose and multidose toxicity in two species (one non-rodent)
• Historical guidelines are 1/10 the LD10 in mice – Death, as an endpoint no longer required
Current FDA Approach to Starting Doses
• Starting dose of 1/10 the dose causing severe toxicity (or death) in 10% of rodents (STD10) on mg/m2 basis
• Provided the same dose causes no severe irreversible toxicity in a non-rodent species (usually dogs)
• If irreversible toxicities are seen, then 1/6 of the highest dose tested in non-rodents that does not cause severe, irreversible toxicity– Occasionally, species specific difference may mandate
the use of alternative species for selection of starting dose
Determine dose severely toxic to 10% of rodents (STD10)
Convert from mg/kg to mg/m2
Mouse x 3; Rat x 6; Guinea-pig x 7.7Hamster x 4.1
Determine non-rodent HighestNon-Severely Toxic Dose
(HNSTD)
Is rodent aninappropriate species?
(biochem, ADME, target, etc)
Is 1/10rodent STD10 (mg/m2)
severely toxic tonon-rodents?
Is non-rodent inappropriate?
Convert from mg/kg to mg/m2
Dog x 20; Monkey x 10Rabbit x 11.6
Start Dose =1/6Non-Rodent HNSTD
NO YES
YES
YESNO
Start Dose =1/10Rodent STD10
NO
Non-Clinical Drug Safety Testingfor Summary of the FDA Perspective
(J. Leighton, FDA ODAC Meeting, March 13, 2006)• Conduct 2 pivotal toxicology studies using the
same schedule, formulation, and route as the proposed clinical trial– Conduct a rodent study that identifies life-threatening
doses– Conduct a non-rodent study that confirms non-life
threatening doses have been identified• Studies of 28 days should be provided for continuous
administration• Studies for one or several administrations, depending on
the schedule for intermittent schedules• Provide full histopathology in one of these studies
– Conduct other studies as needed
Non-Clinical Drug Safety TestingSummary of the FDA Perspective(J. Leighton, FDA ODAC Meeting, March 13, 2006)
• Multiple cycles/continuous treatment generally acceptable, assuming acceptable safety profile in the non-clinical setting
• Pre-IND meeting with sponsors are encouraged to discuss problem areas and provide alternative pathways to initiation of the phase I trial
• Most potential clinical holds resolved through discussion with sponsor
• Guidelines for biologicals (monoclonal antibodies, etc) are in preparation but may differ from small molecule recommendations
An Excellent Resource for Anticancer Drugs(DeGeorge et al Cancer Chemother Pharmacol 1998;41:173)
Plus numerous FDA guidances at http://www.fda.gov/cder/Guidance
Monoclonal Antibody (mAb) Therapeutics
• Targeted mAb are distinct from small molecule therapeutics– Explosion in popularity– Higher approval rates in oncology (~21% vs. <5%)
• High specificity, less off target risk• Long t1/2 (10-21 days)• Novel targets that are difficult or impossible to
modulate by small molecules• Flexible bioengineered design
– Modulation of functional domains
Non-Clinical Toxicology for mAb Therapies
• mAb present major safety challenges• Safety toxicology studies in primates
– Old world primates most common– May exceed primate toxicology resources– Chimpanzees in rare specialized cases
• Primate toxicology may still not predict human effects– TGN1412 anti CD28 super agonist causes non-specific broad
T-cell activation in humans with catastrophic consequences
• Transgenic rodents engineered to express human target may be selectively employed (knock out/knock in animals)
• Surrogate mAb (mouse equivalent) toxicity and efficacy studies to support clinical studies
Starting Doses for Biological Therapies
• Historically, some fraction of the no adverse event level (NOAEL)
• If species specific differences preclude precise dose calculations, then…
• Consider estimations of receptor occupancy, cellular dose response studies from best available models to estimate a Minimum Anticipated Biological Effect Level (MABEL)
• Recommendations for biological therapies are in evolution
An Example of a Phase I study of a Targeted Therapy that Incorporates Biomarkers Developed in Preclinical
Development
AEE788, A Dual EGFR & AEE788, A Dual EGFR & VEGFR Targeting AgentVEGFR Targeting Agent
• Oral receptor tyrosine kinase inhibitor Oral receptor tyrosine kinase inhibitor – A “dirty” kinase inhibitorA “dirty” kinase inhibitor
• 7H-pyrrolo[2,3-d] pyrimidine derivative7H-pyrrolo[2,3-d] pyrimidine derivative• Inhibits EGFR and ErbB-2 receptor tyrosine kinases with Inhibits EGFR and ErbB-2 receptor tyrosine kinases with
ICIC5050’s of 2-6 nM’s of 2-6 nM• Also inhibits multiple other kinasesAlso inhibits multiple other kinases
N
N
HN
NH
N
N
In Vitro AEE788 PharmacologyIn Vitro AEE788 Pharmacology
KinaseKinase ICIC5050 (uM) (uM)
EGFREGFR 0.0020.002ErbB2ErbB2 0.0060.006KDRKDR 0.0770.077HER4HER4 0.0590.059C-AblC-Abl 0.0520.052C-SrcC-Src 0.0610.061RETRET 0.740.74
KinaseKinase IC IC5050 (uM) (uM)
C-KitC-Kit 0.790 0.790 C-MetC-Met 2.902.90Flk, TekFlk, Tek >2>2IGF-1RIGF-1R >2>2PKC-aPKC-a >10>10CDK1/2CDK1/2>10>10
AEE788 Study DesignAEE788 Study Design• Three center N. American/European studyThree center N. American/European study
– C.H. Takimoto, IDD/CTRC, San AntonioC.H. Takimoto, IDD/CTRC, San Antonio– J. Baselga, Vall d’Hebron, Barcelona, Spain J. Baselga, Vall d’Hebron, Barcelona, Spain – A.T. van Oosterom, Catholic University Leuven, BelgiumA.T. van Oosterom, Catholic University Leuven, Belgium
• Dose escalation design of AEE788 orally on a daily Dose escalation design of AEE788 orally on a daily dose schedule in advanced cancer patientsdose schedule in advanced cancer patients– Standard adult phase I patient populationStandard adult phase I patient population– 3-6 patients per dose level allowed3-6 patients per dose level allowed
• Endpoints:Endpoints:– Determine the MTD and DLT of AEE orally on a daily dose Determine the MTD and DLT of AEE orally on a daily dose
scheduleschedule– Characterize drug pharmacokineticsCharacterize drug pharmacokinetics– Extensive pharmacodynamic assessmentsExtensive pharmacodynamic assessments
Dose Levels and DLTs During Cycle 1Dose Levels and DLTs During Cycle 1(Baselga ASCO 2005)(Baselga ASCO 2005)
Dose Level, mgDose Level, mg EnrolledEnrolled Pts with DLT, nPts with DLT, n DLT (n)DLT (n)
2525 55 00 ----
5050 66 00 ----
100100 55 00 ----
150150 55 00 ----
225225 77 00 ----
300300 77 00 ----
400400 77 00 ----
450450 77 00 ----
500500 66 22 Gr 3 diarrhea (2)Gr 3 diarrhea (2)
550550 99 22 Gr 3 diarrhea (2)Gr 3 diarrhea (2)
TotalTotal 6464 44
AEE788 Skin RashAEE788 Skin Rash• Skin rash Skin rash
– Any grade = 42.7%Any grade = 42.7%– Gr 3 or 4 = 0%Gr 3 or 4 = 0%
• Dry skin, fine rash Dry skin, fine rash seen at lower dose seen at lower dose levelslevels
• Pustular macular Pustular macular papular skin rash papular skin rash seen at higher dose seen at higher dose levels (>225 mg/d)levels (>225 mg/d)
AEE788 Other ToxicitiesAEE788 Other Toxicities
• Grade 3 diarrhea (10 pts)Grade 3 diarrhea (10 pts)• Grade 3 fatigue (5 pts)Grade 3 fatigue (5 pts)• Grade 3 anorexia (4 pts)Grade 3 anorexia (4 pts)• Grade 3 hyperbilirubinemia (3 pts)Grade 3 hyperbilirubinemia (3 pts)• No evidence of cardiac toxicity or QTc No evidence of cardiac toxicity or QTc
changes in 2811 EKGs in 96 ptschanges in 2811 EKGs in 96 pts
Delayed Onset Reversible Hepatic Delayed Onset Reversible Hepatic Transaminase ElevationTransaminase Elevation
• Reversible grade 3 / 4 elevations of Reversible grade 3 / 4 elevations of AST/ALT at doses AST/ALT at doses ≥≥300 mg seen in 12 pts300 mg seen in 12 pts
• Median onset of 99 days (after 4 cycles)Median onset of 99 days (after 4 cycles)• Observed in presence and absence of liver Observed in presence and absence of liver
metastasesmetastases• Total bilirubin generally unaffectedTotal bilirubin generally unaffected• Dose and duration of treatment dependentDose and duration of treatment dependent
– Dosing at Dosing at ≥≥300 mg/d for 4+ cycles is 300 mg/d for 4+ cycles is problematicproblematic
AEE788 Efficacy DataAEE788 Efficacy Data
• 83 Patients treated with doses up to 550 83 Patients treated with doses up to 550 mgmg– One PR in angiosarcoma at 400 mg now One PR in angiosarcoma at 400 mg now
completed 5 cyclescompleted 5 cycles– 36 of 83 pts (43%) with stable disease 36 of 83 pts (43%) with stable disease
beyond 2 cyclesbeyond 2 cycles– Median number of cycles that patients Median number of cycles that patients
remained on study is 2 (range 0.5-14)remained on study is 2 (range 0.5-14)
Planned PD AssessmentsPlanned PD Assessments
• Skin biopsies in 53 ptsSkin biopsies in 53 pts• Vascular IHC analyses in 32 ptsVascular IHC analyses in 32 pts• Tumor biopsy IHC data from 15 ptsTumor biopsy IHC data from 15 pts
DailyAEE788
Skin (wound) biopsy day -1
Skin biopsy day +22
w1 w2 w3 w4 w5
Skin (wound) biopsy day +29
Skin biopsy day-8
Cycle 1 Cycle 2
Tumor biopsy day -14 to -1
Tumor biopsy day +28
Biopsy samples were evaluated by immunohistochemistry (IHC) and scored by Hscore. Hscore = (% faint stained cells) + (% moderate stained cells)*2 + (% strong stained cells)*3. Ki67 was scored by % positive cells --Baselga et al, ASCO 2005
Results: Skin (basal epidermis) p-EGFRResults: Skin (basal epidermis) p-EGFR
25mg 50mg 100mg 150mg
90
60
88
59
75 7573 73
0
30
60
90
120
150
Hscore basal pEGFR day -7 Hscore basal pEGFR day +22
75
45
120
105105
60
48
30
0
30
60
90
120
150
Hscore basal pEGFR day -7 Hscore basal pEGFR day +22
105
15
75
15
7875
12
30
60
42
0
20
40
60
80
100
120
Hscore basal pEGFR day -7 Hscore basal pEGFR day +22
60
15
30
75
60
42
0
30
60
90
120
150
Hscore basal pEGFR day -7 Hscore basal pEGFR day +22
225mg 300mg 400mg 550mg
75
42
72
30
17
30
15
54
28
15
0
30
60
90
120
150
Hscore basal pEGFR day -7 Hscore basal pEGFR day +22
72
15
54
12
72
24
36
6
60
30
0
30
60
90
120
150
Hscore basal pEGFR day -7 Hscore basal pEGFR day +22
66
0
45
0
30
60
90
120
150
Hscore basal pEGFR day -7 Hscore basal pEGFR day +22
48
0
30
0
72
0
30
0
30
60
90
120
150
Hscore basal pEGFR day -7 Hscore basal pEGFR day +22
--Baselga et al, ASCO 2005
Pharmacodynamic ModelingPharmacodynamic Modeling
--Baselga et al, ASCO 2005
Tumor Biopsy IHC Results (n=15)Tumor Biopsy IHC Results (n=15)pEGFR pMAPK pAkt Ki67
25 mg25 mg
Pre-RxPre-Rx
During RxDuring Rx
550 mg550 mg
Pre-RxPre-Rx
During RxDuring Rx
--Baselga et al, ASCO 2005
PD Tumor Marker ChangesPD Tumor Marker Changes
Maximal pEGFR SuppressionMaximal pEGFR Suppression
--Baselga et al, ASCO 2005
Pharmacodynamic FindingsPharmacodynamic Findings• Inhibition of molecular targets was dose and serum concentration Inhibition of molecular targets was dose and serum concentration
dependent with significant variablitydependent with significant variablity– Active concentration = AEE788 (parent) + AQM674 (active metabolite)Active concentration = AEE788 (parent) + AQM674 (active metabolite)
• Tumor pEGFR inhibition (ICTumor pEGFR inhibition (IC5050 18 nM) agrees with A431 cell line data 18 nM) agrees with A431 cell line data (IC(IC5050 = 11 nM) = 11 nM)
• Skin PD PotencySkin PD Potency– TestTest ID80ID80– pEGFR/pMAPKpEGFR/pMAPK 225-250 mg225-250 mg– Ki67Ki67 50-100 mg50-100 mg
• Tumor PD Potency (greater than skin)Tumor PD Potency (greater than skin)– TestTest ID80ID80– pEGFRpEGFR 150 mg150 mg– pAktpAkt 100-150 mg100-150 mg
• Optimal biological dose may be ~250 mg(?)Optimal biological dose may be ~250 mg(?)
AEE788 Phase I Study AEE788 Phase I Study ConclusionsConclusions
• Cycle 1 DLT was grade 3 diarrhea despite supportive Cycle 1 DLT was grade 3 diarrhea despite supportive care at 500-550 mg/dcare at 500-550 mg/d– Other toxicities: fatigue, nausea, rash, anorexia, vomiting, Other toxicities: fatigue, nausea, rash, anorexia, vomiting,
stomatitisstomatitis
• Chronic dosing revealed grade 3/4 hepatic transaminitis Chronic dosing revealed grade 3/4 hepatic transaminitis at doses >300 mg after 4 cyclesat doses >300 mg after 4 cycles
• PK/PD analysis suggests dose PK/PD analysis suggests dose ≥≥250 mg may optimally 250 mg may optimally modulate biological target(s)modulate biological target(s)
• Further exploration of daily 250 mg dosing and Further exploration of daily 250 mg dosing and alternative schedules is ongoingalternative schedules is ongoing– PK/PD biomarker data highly useful in clinical decision making PK/PD biomarker data highly useful in clinical decision making
processprocess
The Clinical Trial Challenge• We stand at the dawn of the post genomic era
when new targets for novel treatments for human cancer are just being discovered and defined
• Basic research is the engine that drives this process
• Clinical researchers have to take these promising agents and test them in the best and most efficient ways possible – Traditional clinical endpoints, and…– Molecular target endpoints in clinical studies
The Challenge!
PreclinicalPharmacology
Traditional animal studies
PK/PDToxicology
Molecular targets
ClinicalPharmacologist
Early Phase IPharmacokinetic
Clinical Trials
Traditional dose and toxicity endpointsTraditional PK/PD
Molecular andbiochemicalendpoints
New Paradigms for Drug Development in the Post Genomic Era
• Expanding role for translational studies in Phase I clinical trials
• Bridge the gap between preclinical pharmacologic studies and early clinical trials
• New molecular and biochemical endpoints are essential for cancer prevention and antimetastatic agents
• This is an exciting time to be developing new anticancer drugs!
New Phase I Paradigms: New Phase I Paradigms: Evolution not Revolution!Evolution not Revolution!