Novel Strategies for the Treatment of AML: Tailoring

Treatment For Specific Genetic Subtypes

Martin S. Tallman, M.D. Northwestern University Feinberg School of

MedicineRobert H. Lurie Comprehensive Cancer Center

Chicago, IL

Topics To Address• Introduction and epidemiology

• Overview of current therapy

• Distinguishing genetic subtypes

• Novel strategies for specific genetic subtypes

• Future Directions

Introduction

• New patients/deaths in 2004: 12,000/9,000

• Median age of AML: 68 years

• Heterogeneity in genetics and clinical manifestations

• Outcome varies by prognostic factors

Epidemiology• Therapy-related (alkylating agent or topo II

active agents)

• Evolving from MDS or MPD

• Congenital chromosomal instability syndromes

• Higher frequency of APL in Latin Americans1

• Higher frequency of t(8;21) in Japan2

1Douer Blood, 1996, Br J Haematol, 2003; 2Nakase Leukemia, 2000

Current Treatment Results In Younger Adults

STUDY N CR % ED % OS % (3-5 yr)

CALGB 474 72 9 34

GAMLCG

HOVON

535

253

74

77

11

7

39

38

ALFA 345 82 9 38

Current Treatment Results In Older Adults

STUDY N CR % ED % OS % (2-7 yr)

CALGB 388 52 25 15

ECOG 348 42 17 10

SWOG 328 43 7 19

MRC 1,314 55 19 10

Prognostic Factors

• Age

• Intensity of postremission therapy (younger adults)

• Cytogenetics (distinguish fav- intermed- and unfav-risk groups)

Overall Survival by Cytogenetic Group

Slovak Blood, 2000

Years After Entering Study

0

20

40

60

80

100

0 2

Cu

mu

lati

ve P

erce

nt

84 6

Favorable 121 53 55% Intermediate 278 168 38% Unfavorable 184 162 11%

Estimate At Risk Deaths at 5 Years

Heterogeneity of 3 Groups: p<.0001

Prognostic FactorsMolecular Markers

• Transmembrane transporter proteins which confer multidrug resistance (MDR1)

• Mutations in or overexpression of specific genes-unfav. prognosis: WT1, BAX, BCL-2/BAX, BAALC, EVI1, KIT, FLT3, MLL, ERG; fav. prognosis: C/EBP, NMP1

Expressed in cells from pts with normal karyotype

Outcome For AML with Fav-risk Cytogenetics

N CR % DFS % OS %

CBF 3731

3122

86

88

40

47

43

50

1613 96 52 59

APL 4634 91 88 85

2985 94 90 871Castaigne Blood, 2002; 2Appelbaum Proc ASCO, 2005; 3Marcucci J Clin Oncol,

2005; 4Sanz Pro ASCO, 2005; 5Lo Coco Blood, 2004

Outcome For AML in Older Adults with

Unfavorable Cytogenetics

N CR% OS% (5-yr)

MRC1 145 26 2.0

ECOG2 61 23 2.5

1Grimwade Blood, 2004; 2Rowe Blood, 2004

Current Therapeutic Strategies

• Induction with anthracycline 45-60 mg/m2/day for 3 days + cytarabine 100 mg/m2/day for 7 days c.i.

• Multiple cycles of high-dose ara-C consolidation

• No maintenance (except APL)

Strategies To Improve Outcome

• Dose intensification (anthracyclines)

• Alternative chemotherapy

• Priming with growth factors

• New agents

Daunorubicin Dose Intensification

1Appelbaum Ann Int Med, 1984; 2Castaigne Blood, 2003; 3Kolitz Blood, 1998

Study Dauno Dose CR%

FHCRC1 70 mg/m2 80

ALFA2 80 mg/m2 76

CALGB3 90-95 mg/m2 80

ECOG Priming StudiesRecruiting Leukemic Cells into Cell

Cycle

GM-CSF Placebo

CR 38% 40%

Induction mortality 26% 17%

OS, median 5.3 mo. 8.5 mo.

DFS, median 6.9 mo. 5.1 mo.

Rowe Blood, 2004

Priming With Growth Factor (GF) in Younger Patients with Intermediate

Cytogenetics

Study N CR % DFS % OS %GF/No GF GF/No GF GF/No GF

HOVON1 464 87/86 45/33 (p=.006)

45/35 (p=.02)

ALFA2 259 91/87 50/35 (p=.05)

56/47(p=.07)

1Lowenberg NEJM, 2003; 2Thomas Blood, 2005

Specific Genetic Subtypes of AML To Which Therapy Can Be

Tailored• APL

• CBF AML

• CD33 pos AML

• AML with FLT3 mutatations

• AML with c-kit mutations

• AML with MLL PTD

Curative Strategies in APLInduction: ATRA + anthracycline-based

chemotherapy

Consolidation: Anthracycline-based chemotherapy for 2-3 cycles to molecular negativity

Intermediate-dose ara-C for high-risk

Maintenance: ATRA +/- low-dose chemo for 1-2 years; ? Role in PCR neg after consol

Mol. Monitoring: RT-PCR from PB every 3-6 months for 2-3 years, prob for high-risk only

Relapse: Arsenic followed by ASCT (allo if PCR pos) (consider prophylactic IT

therapy)

GIMEMA AIDA 2000

Years

Su

rviv

al

0 .5 1.0 2.0 3.0 4.0

0

.25

.50

.75

1.0

N=3383 years: 87%

1.5 2.5 3.5

Overall Survival

Courtesy of F. Lo Coco

Advances in Therapy in APLParadigm for tailoring therapy to

specific genetic subtypeStudy Group ContributionNo. Am. Intergroup Maintenance

PETHEMA Elimination of ara-C

PETH/GIMEMA ATRA in consolidation

No. Am. Intergroup ATO in consolidation

GIMEMA Gemtuzumab

Shanghai ATRA + ATO

Iran ATO single agent

Will chemotherapy be eliminated?

Arsenic Trioxide for Rel/Ref APLPilot and US Multicenter Trial

Overall and Relapse-Free Survival

Years

0

20

40

60

80

100

0

Pro

bab

ility

(%

)

1 4

OS - 1st Relapse

2 3

OS - > 1st RelapseRFS - 1st RelapseRFS - > 1st Relapse

Soignet J Clin Oncol, 2001; Douer, Tallman J Clin Oncol, 2005

< .02*

0

11.1

26.3

Relapse (%) (median follow-up 18 months)

< .01

119

32

6.7

PML/RARα (fold)

< .05

25 5

35 3

40 10

Time to CR (days)

NS

95

90

95

(%)

CR

—P

21ATRA + ATO

20ATO

20ATRA

N

Induction/ maintenance therapy

*All patients also treated with consolidation chemotherapy and 6-MP + MTX as maintenance

Randomized Trial of Arsenic Trioxide and ATRA in Untreated APL

Shen Proc Natl Acad Sci,U S A, 2004

Time of Follow-up (months)

0

0.2

0.4

0.6

0.8

1.0

0 8

Probability

3216 244 2812 20

ATRA + arsenic trioxide (n = 20)arsenic trioxide (n = 18)ATRA (n = 19)

Shen PNAS, 2004

Disease-Free Survival by Treatment Group

1Zhang J Biol Regul Homeost Agents, 19992Ghavamzadeh ASCO, 2003[abst]3Ghavamzadeh EHA, 2004[abst]

Induction With Single-Agent Arsenic Trioxide: Untreated APL

51

111

124

N

95

92

NR

PCR neg (%)

ATO 6

ATO 1

Chemotherapy

Postremission therapy

80

86

88

CR (%)

Chandy – India5,6,7

Ghavamzadeh – Iran2,3,4

Zhang – China1

Study

4Ghavamzadeh Ann Oncol, 20055George Haematologica, 20046George European Hematol Assoc, 20047Mathews Blood, 2005 (abstr)

North American Intergroup Trial C9710

Induction Consol #1 Consol #2 Maint

ATRA DaunoAra-C

ATOATRADauno

CR

ATRA6-MPMTX

ATRA7 days, QOW

UntreatedAPL

No ATO

Tests arsenic as early consolidation and 2 maint regimens

Proposed North American Intergroup Study-Phase III

Low- and Intermediate-Risk

Induction Consol #1 Consol #2 Maint

ATRA Daunorubicin

Ara-CATO

ATRADaunorubicin

PCR

ATRA6-MPMTXneg

pos

OBS

GemtuzumabOzogamicin

HSCTTests benefit of maint in PCR neg patients

Proposed North American Intergroup Study-Phase II

High-Risk

Induction Consol #1 Consol #2 Consol #3 Maint

ATRAATO

GemtuzumabOzogamicin

ATO ATRADaunorubicin

GemtuzumabOzogamicin

ATRA6-MPMTX

Tests benefits of 3 nonchemotherapy agents in induction

Incidence of CBF AML by Age

Age Total inv(16) t(8;21) P-value

16-30 27% 43% 57% 0.056

31-40 26% 55% 45%

41-55 27% 59% 41%

56-65 9% 50% 50%

66-83 10% 62% 38%

Appelbaum FR, Kopecky KJ, Tallman MS, et al (submitted)

Outcome of t(8;21) AMLStudy N CR OS Postrem

Palmeri 17 82% 79% HiDACx3

Nishii 85 95% 52% No I-or HDAC

Baer 29 90% 45% >/=1 HiDAC

Marcucci 139 89% 46% S-, I-, HiDAC

Appelbaum

Schlenk

174

191

85%

87%

45%

65%

Variable

HiDAC

Palmeri Leuk Res, 2002; Nishii Leukemia, 2003; Baer Blood, 1997; Marcucci J Clin Oncol, 2005; Appelbaum (submitted); Schlenk J Clin Oncol, 2004

Outcome of inv16/t(16;16) AML

Study N CR OS Postrem

Marcucci 164 87% 54% S-, I-HiDAC

Delaunay 110 93% 58% variable

Appelbaum 196 89% 50% variable

Schlenk 201 89% 60% HiDAC

Marcucci J Clin Oncol, 2005; Delaunay Blood 2003; Appelbaum (submitted); Schlenk J Clin Oncol 2004

Overall Survival

Years0 10 20 25

100

Per

cent

0

40

60

80

20

5 15

5YearN Deaths Estimate

All Patients 370 197 48%

Overall Survival by Abnormality

Years0

100

Per

cent

0

40

60

80

20

5YearN Events Estimate

inv 16 196 97 50%t(8;21) 174 100 45%

10 20 255 15

Disease-Free Survival by Treatement

Years After Start of Post-CR Regimen0

100

Per

cent

0

40

60

80

20

5YearN Events Estimate

FA 53 20 61%HCT 31 12 61%HDAC 44 23 50%Other 136 96 31%

10 20 255 15

Outcome for CBF Leukemias

Appelbaum et al.(submitted)

CALGB Protocol 19808: Induction +/- MDR Modulation Followed by Cytogenetic Risk-

Adapted Intensification in Younger Adults

ADE

ADEP

Favorable Cytogenetics

Unfavorable Cytogenetics

HiDACConsolidationTherapy x 3

If able toReceive PSCT

If unable toReceive PSCT

HiDACG-CSF VP-16

Stem CellMobilize

VP-16HiDACG-CSF

BU/VP-16PSCT

HiDACConsolidationTherapy x 2

Obs.

IL-2

Tests HiDAC for fav. Cyto and IL-2 post-ASCT

Specific Genetic Subtypes Are Heterogeneous: t(8;21)

• CD56 expression may confer poor prognosis

• Associated trisomy 4 is a distinct subtype with poor prognosis

• Receptor tyrosine kinase pathway mutations in 49% and confer poor prognosis

Baer Blood, 1997; Nishii Leukemia 2003; Nanri Leukemia 2005

New AgentsClass Agent Target

Antibodies Gemtuzumab CD33

MDR inhibitors PSC833, Zosuquidar P-gp

FT inhibitors Tipifamib Lamin A, HJJ-2

FLT3 inhibitors PKC-412, CEP-701, MLN518, SU11248

FLT3 ITD

HDAC inhibitors Valproic acid, SAHA, depsipeptide

HDAC

Antiangio agents Bevacizumab VEGF

Apoptosis inhibitors Genasense BCL-2

Deoxyadenosine analogs

Nucleoside analogs

Clofarabine

Tiazofurin

DNA

IMPDH

S

H

HOO

OCH

NH O

O

OCH 3

N

EtO

OHOCH 3

HOCH3

OCH3

HNHO

OO

OH

CH3

S

CH3

OCH 3

OCH 3

I

O

O

O

O

O

CH 3

S

O

NHN

Me Me

Me

OO

HN

hP67.6

Gemtuzumab Ozogamicin

• Approved for adults > 60 in first relapse

• Induces CR + CRp in ~ 30%1,2

• Rare VOD/SOS if allo < 3.5 mo.3

•Structure hP67.6 - humanized anti-CD33 antibody Blue- linker Periwinkle - calicheamicin

1Sievers J Clin Oncol, 2001; 2Larson Leukemia, 2002; 3Wadleigh Blood, 2003

Gemtuzumab OzogamicinCR

MD Anderson1

Single Agent 8%

With IL-11 36%

Northwestern2 27%

EORTC3

Single Agent 23%

Followed by Chemo 35%

1Estey Blood, 2002; 2Nabhan Leukemia Res, 2004; 3Amadori Blood, 2004 [abstr]

Gemtuzumab Ozogamicin in Induction

DeAngelo Blood, 2003 (abstr); Kell Blood, 2003

Study Chemotherapy GO Dose CR

DeAngelo Dauno/Ara-C 6 mg/m2 d4 83%

Kell DAT or FLAG-ida 3 mg/m2 d1 85%

Prompts SWOG Phase III trial of chemotherapy +/- GO d4

ECOG Protocol E1900: Dose Intensification in Induction and Gemtuzumab Ozogamicin (GO) pre-ASCT in Younger Adults with

Untreated AML

Daunorubicin45 mg/m2/day

+Cytarabine

Allogeneic HSCT

CR

Daunorubicin90 mg/m2/day

+Cytarabine

High Risk

HiDAC x 2PBSH after 2nd

courseGO

6 mg/m2 IV day 1

AutologousASCT

Tests anthracycline dose intens and GO as in vitro purge pre- ASCT

Inhibition of Multidrug Resistance

• P-gp-mediated MDR plays major role in clinical resistance to chemotherapy

• P-gp correlates inversely with CR

• 71% of patients > age 60 express moderate to high P-gp1

• Major limitation is alteration in pK of concomitant chemotherapy

1Leith Blood, 1994

Group Modulator Regimen Outcome

CALGB1 PSC-833 ADE+PSC-833 Closed due to

toxicity

HOVON2 PSC-833 DA+PSC-833 DFS, OS not

improved1Baer Blood, 1999; 2 Van der Holt Blood, 2004 (abstr)

MDR Modulation Studies in AMLDe novo > 60 years

Inhibition of Multidrug Resistance

• Selective P-gp inhibitor with high affinity1

• In vitro conc of 50-100nM circumvent P-gp-mediated resistance 2,3

• Does not alter PKs of co-administered drugs2

• Phase II trial in poor-risk AML CR or mCR 42%4

• ECOG phase III trial

LY335979 (Zosuquidar)

1Sato Cancer Res, 1991; 2Dantzig Cancer Res, 1996; 3Green Biochem Pharmacol, 2001; 4Cripe Blood, 2001 (abstr)

ECOG Protocol E3999: Dauno + Cytarabine+/- Zosuquidar in Older Adults

DaunorubicinCytarabine

Zosuquidar

Induction Consolidation I

Daunorubicin

Cytarabine

Placebo

V

A

L

U

A

T

E

E

CR or

MR

Cytarabine

Consolidation II

Daunorubicin

Cytarabine

Zosuquidar

Daunorubicin

Cytarabine

Placebo

Tests novel MDR modulator

Ras• Ras mutations

– Activating mutations in 10-30% of AML1,2 – Frequent in t(3;5) and inv(16)3

• Active inhibition of farnesyl transferase (FT), inhibits ras protein

• Inhibitors of FT active in AML4,5

• Gene expression profiling may predict response to Tipifarnib6

1Radich Blood, 1990; 2Neubauer Blood, 1999; 3Bowen Blood, 2005;

4Karp Blood, 2001; 5Lancet Blood, 2002; 6Raponi Blood, 2005

Tipifarnib-Phase II Trial in Untreated High-risk AML/MDS

• Med age 74 yrs (46-85)• CR in 21%• Med CR dur 5-8 mo. (1.5-11+)• Gr. 4 neutropenia 13%• Inhibition of FT in 74% of samples• Encouraged US Intergr Phase II trial of

2 different doses/schedules in older adults

Lancet Blood, 2003 (abstr)

S0432: US Intergroup Phase II Study Zarnestra for Previously Untreated AML in

Patients > Age 70

Randomization

Arm 1 Arm 2 Arm 3 Arm 4

Zarnestra 600 mg

bid x 21 daysq 28 days

Zarnestra 600 mg bid x 7 days every other week q 28

days

Zarnestra 300 mg

bid x 21 daysq 28 days

Zarnestra 300 mg

bid x 7 days every other week q 28

days

AML With Mutant RAS and Cytarabine Intensification

wtRAS mutRAS

LoDAC HDAC LoDAC HDAC

Yrs to relapse

0.8 1.1 0.6 NR

RR 82% 71% 100% 45%

Neubauer ASCO, 2005

0

40

20

60

100

0 1

Su

rviv

al (

%)

Years2 3 4 5

80

44%44%

32%32%

ITD- n=627ITD- n=627

ITD+ n=227ITD+ n=227

P<0.001P<0.001

Kottaridis Blood, 2001

Prognostic Significance of FLT3 ITD

Tyrosine Kinase Inhibitors

PKC412• Staurosporine-derived, targets PKC, KDR, VEGF-R2,

PDGFR, c-KIT, FLT3

• Phase II study1 – 28 pts with FLT3 mutation, HI in 50%, but no CR or PR

CEP-701• Indolcarbazole alkyloid-targets TrkA, VEGFR, FLT3

• Phase I/II study2-14 pts with FLT3 mutation, biologic activity in 35%, but no CR or PR

1Estey Blood, 2003; Smith Blood, 2004

FLT3 Inhibitors and Chemotherapy in AML

•CEP-7011

•N=34 in first relapse•MEC or HiDAC +/- CEP-701•10/17 CR with CEP-701

•PKC4122

•N=19 de novo•Dauno + Ara-C + PKC412•CR 71-75%•100% FLT3 mut•62% FLT3 wt

1Lewis, Blood, 2005 (abstr);

2 Stone, Blood, 2005 (abstr)

FLT3 Inhibitors• In vitro data strong

• Modest clinical activity-few, if any, CRs

• How best to develop? • Focus on combinations with chemotherapy1, 2;

Phase III US Intergroup trial planned (dauno + ara-C +/- PKC412)

• Will combining agents with in vitro activity, but modest clinical activity, be effective?

1Stone Blood, 2005; Levis, Blood 2005

Genasense (Oblimersen Sodium)• Bcl-2 associated with poor outcome in AML

• Phosphorothioate 18-mer antisense oligonucleotide directed at first 6 codons of Bcl-2

• Genasense + dauno/cytarabine in high-risk de novo pts– 26 pts, med. age 67 – CR in 45.4%; no unexpected toxicity

• CALGB phase III trial underway

Marcucci Blood, 2003

G3139+

Cytarabine +Daunorubicin

Cytarabine +Daunorubicin

High-Dose Cytarabine

G3139+

High-DoseCytarabine

CALGB 10201: Daunorubicin + Cytarabine +/- G3139 (Genasense)

in Older Adults

CR

RemissionInduction

ConsolI & II

CR

Tests bcl-2 antisense strategy

Clofarabine• Intentionally designed to incorporate

the favorable properties of fludarabine/cladribine

• Multiple mechanisms of action

– Inhibits DNA replication and repair

– Disrupts mitochondrial function leading to apoptosis

• Active in both dividing and non-dividing cells

Clofarabine Trials in AML

Regimen N Population

CR/OR %

Clo 31 Rel/Ref 01

Clo 28 Untreated 59/752

Clo +IDAC 25 Rel/Ref 22/383

Clo + IDAC 60 Untreated 52/604

Clo + LoDAC 32 Untreated 59/625

1Kantarjian Blood, 2003;2Faderl Blood, 2005; 3Burnett Blood, 2005; 4Faderl Blood, 2005; 5Faderl Blood, 2005

CClofarabine Low-dose cytarabine

DDaunorubicin Cytarabine

Clofarabine

CClofarabine Low-dose cytarabine

CCytarabine 1.5 mg/m2 IV Q12 d1-6

CCytarabine 1.5 g/m2 IV Q12 d1-3

CClofarabine

Age 60-69

R

R

No CR Off Study

Age 70-79

HLA-iden sibling Mini-MUD alloSCT

Proposed ECOG Trial

CR

Can we eliminate conventional chemotherapy in older adults?

Specific Genetic Subtypes Of AML To Target In The Very

Near Future

• C-KIT AML: Imatinib, Dasatinib, FLT3 inhibitors

• MLL PTD AML: HDAC and DMT inhibitors

• Bcr-abl pos AML: IMP dehydrogenous inhibitor (Tiazofurin )

Whitman Blood, 2005; Malek Leuk Res, 2004

Other Active Agents Awaiting Assignement

To Specific Genetic Subtypes

• Choretazine (VNP40101M): sulfonylhydrazine alkylating agent1

• Tandutinib: small molecule inhibitor or type II receptor tyrosine kinases2

• XL99: inhibits multiple receptor kinases(VEGFR-2, PDGFR-alpha, PDGFR-beta, c-KIT, SRC, FGFR1, FLT4, FLT3)

• Low-dose decitabine3

• Arsenic plus low-dose ara-C41Giles Blood 2005 (abstr); 2Deangelo Blood, 2004 (abstr);

3Lubbat Blood, 2005 (abtsr); 4Robosz Blood, 2005(abstr)

Future Directions

• Gene expression profiling to determine signatures characteristic of specific genetic subtypes, identify cooperating mutations and perturbed pathways and predict treatment response

• Further characterization of normal karyotype AML and adverse karyotype AML

• Increased collaboration among cooperative groups to study myriad of new agents to tailor to specific genetic subtypes