RANDOLPH ASHEBORO YMCA INDOOR CYCLE STUDIO APRIL

Myeloproliferative Neoplasms
Myeloproliferative Neoplasms
The Path to Targeted Agents
Disclosures
• Member, Advisory Committee, 2011 – Incyte Corporation
• I will discuss the off‐label use of medications and medications used in the context of clinical trials only.
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Outline of Topics
Outline of Topics
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Case based Review
Case‐based
Review
Historical Context
Therapeutic Context
h
i C
2005 and the discovery of JAK2
Effects on Therapy?
Where to now?
Where to now? Case #1: JG
Case #1: JG
• 43
43 yo woman
yo woman
• In Aug of 2006 
Abdominal Pain
Abdominal Pain.
• Idiopathic portal vein thrombosis Thought to
thrombosis. Thought to be due to OCPs.
• Anticoagulated.
Anticoagulated
• Mid 2010 – Abdominal pain and fatigue
pain and fatigue
Case #1: JG
Case #1: JG
Case #1: JG
Case #1: JG
• Labs demonstrated:
Labs demonstrated:
– WBC: 5.6 k/uL
– Hgn: 13.6 gm/dL
g
g /
– Platelet Count of 610 k/uL
• Smear
Smear shows polychromasia and burr cells, shows polychromasia and burr cells,
occasional dacrocyte (or tear drop cell)
• Liver Function Panel Normal
Liver Function Panel Normal
• Congenital Clotting Disorders – Negative
• JAK2 gene mutation positive
JAK2 gene mutation positive
Case #2: EW
Case #2: EW
• 36 yo woman
36 yo woman
• First Pregnancy
Interuterine fetal demise
Interuterine fetal demise
at 22 wks gestation
• Platelet count of 680 k/uL.
• Jak 2 Positive
• Consistent with a diagnosis of Essential Thrombocythemia
Case #2: EW
Case #2: EW
• Pregnancy #2
Pregnancy #2
– Prophylactic level anticoagulation
– Complicated by placental abruption, rapid Complicated by placental abruption rapid
maternal hemorrhage, pre‐eclampsia and late fetal demise
fetal demise
Case #2: EW
Case #2: EW
• Pregnancy #3
Pregnancy #3
– Anticoagulation with therapeutic level low‐
molecular weight heparin and aspirin
molecular weight heparin and aspirin
– Anti‐XA levels measured (peak and trough), Q2 weeks.
– Successful delivery of healthy infant
• Same with Pregnancy #4
Same with Pregnancy #4
• Currently: 4.9>‐13.9<320
Myeloproliferative
Disorders
Myeloproliferative Disorders
MPN (WHO 2008)
MPN (WHO 2008)
BCR/ABL Positive
BCR/ABL Negative
g
PV
ET
PMF
Others
CML
Epidemiology
Polycythemia Vera
Essential Thrombocytosis
Primary Myelofibrosis
Annual Incidence
Annual Incidence
Median Survival
Median Survival
1.9‐2.3/100,000
12.6 years in PVSG studies
2.5/100,000 individuals. 10‐year survival roughly 64%‐80%
May equal age‐matched controls
t l
0.4‐1.3/100,000
Median survival ranges from less than 2
years to greater than 15
years to greater than 15 years on the basis of currently
identified prognostic factors
Polycythemia Vera
Polycythemia Vera
• Cardinal Features of PV
Cardinal Features of PV
– Increased red cell mass
– Hypercellular BM with increased numbers of Hypercellular BM with increased numbers of
erythroid, megakaryocytic, granulocytic precursor cells
– Variable increase in reticulin fibers
– Thrombotic Risk>Bleeding; Vasomotor SX
Thrombotic Risk>Bleeding; Vasomotor SX
– Arterial and Venous clotting
– Risk of leukemic transformation
Risk of leukemic transformation
Essential Thrombocythemia
Essential Thrombocythemia
• Cardinal Features of ET
Cardinal Features of ET
– Increased Megakaryocytes and Platelets
and Platelets
– Median age 60; F>M
– Propensity for hemorrhage
Propensity for hemorrhage
– Thrombosis includes stroke, TIA CVST abdominal veins
TIA, CVST, abdominal veins
– Pregnancy complications
– Rare transformations to AML
Rare transformations to AML
– Progression to MF
Primary Myelofibrosis
Primary Myelofibrosis
• Cardinal
Cardinal Features of PMF
Features of PMF
• Previously called chronic idiopathic myelofibrosis (CIMF) and agnogenic myeloid
myelofibrosis (CIMF) and agnogenic myeloid metaplasia
• Often an older patient, with sx related to Of
ld
i
ih
l d
splenomegaly – including fatigue, NS, weight loss. • Shorter OS, secondary to cytopenias, transformation to AML
MF Transformation
PV 20 yr: 30%
ET 20yr: 20%
AML
Transformation
PV 20 yr: 15%
ET 20yr: 8%
Thrombosis:
PV 22-35%
22 35%
ET: 23-29%
MF 20yr: 25%
Topics to Cover
Topics to Cover
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•
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Overview of Diseases
Overview
of Diseases
Historical context
Therapy Up to Now
h
Therapy In the Future?
Pitfalls and Open Questions
ESSENTIAL THROMBOCYTHEMIA
EMIL EPSTEIN & ALFRED EMIL
EPSTEIN & ALFRED
GOEDEL Hemorrhagic Thrombocythemia… a case of extreme thrombocytosis
of extreme thrombocytosis, erythocytosis and mucocutaneous bleeding and no panmyelosis….
MYELOFIBROSIS
GUSTAV HEUCK
Falle von Leukamie mit Falle
von Leukamie mit
eigenthumlichem Blut‐resp. Knochenmarksbefund “Two cases of leukemia with peculiar blood and bone marrow findings” Arch Pathol Anat Physiol Virchows 1879
POLYCYTHEMIA VERA
Louis Henri Vasquez
40 yr old man with chronic cyanosis*, vertigo, dyspnea, palpitations, hepato‐
splenomegaly and and
erythrocytosis
WILLIAM OSLER
WILLIAM OSLER
4 cases of chronic cyanosis, with polycythemia and enlarged spleen *Cyanosis =
ruddiness,
congestion
From Description to Hypothesis
William Dameshek (1900
William Dameshek
(1900‐1969)
1969)
….is it possible that these various conditions is it possible that these various conditions – “myeloproliferative
myeloproliferative disorders”– are all somewhat variable manifestations of proliferative activity of the bone marrow cells, perhaps due to a hitherto undetected stimulus? …
William Dameshek, 1951, Blood
Essential Questions for Neoplasia
Essential Questions for Neoplasia
• Clonal?
• What is the cell of origin?
Answers to both of these questions addressed with
• Answers to both of these questions addressed with studies of women who were heterozygotes for G6PD
A Stem Cell Disorder?
A Stem Cell Disorder?
• Early
Early studies used Females who were G6PD studies used Females who were G6PD
heterozygotes Fialkow ‐‐ MPN generally were clonal in
generally were clonal in origin
 Adamson ‐‐
Adamson clonality
was present in WBCs, platelets and RBCs
p
 Confirmed in recent studies (T‐cell, B‐cells, NK cells, also)

Xa
Xb
Xb
Xa
Xb
Xa
Xa
Xb
Xb Xb Xb
Xb Xb Xb
Xb
b
Xb Xb
Xa
Xa
Xb
Xb
Xa
Xa
Xb
Xb
Xa
Xa
Xb
Xb
Xa
Xa
Xb
Xb
Xb
Xb
Xa
Xa
Xb
Xa
Xa
So… by the mid‐1970s
So… by the mid
1970s
• Myeloproliferative
Myeloproliferative Disorders are considered Disorders are considered
variations of the same disease. • They are proven to be clonal ‐‐
They are proven to be clonal and
• In 1974, studying individuals with PV, researchers found that h f
d h
– Blood cells could grow in the absence of erythropoeitin
h
ii
– Demonstrated constitutative proliferative capacity
Then… in 1973
Then… in 1973
Implications
• First
First off off – separated out CML as a unique separated out CML as a unique
molecular entity
• Within 20 years led to the development of Within 20 years led to the development of
Imatinib – a targeted agent that blocks the kinase activity of the BCR ABL molecule
kinase activity of the BCR‐ABL molecule
• Spurred additional research on what could be the molecular pathogenesis of the BCR‐
h
l l
h
i f h BCR
negative MPDs
Molecular Understanding of MPNs
1951
Essential Thrombocythemia
y
(ET),
( ) PV and Myelofibrosis
y
(MF)
( )
recognized as similar syndromes by Dameshek
1974
Discovered that the erythroid precursors in PV grow in the
absence
b
off EPO stimulation
ti l ti
1983--2003
1983
Mutations in tyrosine kinases described in other MPDs,
including CML, Mastocytosis, Eosinophilia
2001--2004
2001
EPO-independent
EPOp
g
growth shown to be dependent
p
on JAKJAKSTAT signaling pathway.
2005
Inhibitors of JAK2  hampered erythroid production in PV cell
lines
Adapted from Campbell NEJM 2006
Janus Kinase 2 (JAK2)
Janus Kinase 2 (JAK2) • JAK2 is a cytoplasmic tyrosine kinase which instigates intracellular signaling when
instigates intracellular signaling when triggered by the receptors
– Erythropoeitin
y
p
– Thrombopoetin
– IL3 – GCSF
– GMCSF
2005 Discoveries
2005 Discoveries
• Four major studies – all published within 3 weeks of one another
• All generally confirmatory of one another, but also each one with slightly different methods and aims
with slightly different methods and aims
• All four groups identified a single recurrent mutation Baxter EJ et al
Lancet March 19, 2005
Kralovics R et al
NEJM April 28, 2005
James et al
Nature April 28, 2005
Levine RL et al
Cancer Cell April 2005
2005 Discoveries
2005 Discoveries
• A
A single point mutation identified single point mutation identified
in the JAK2 kinase which changed a G T in exon 14 This exon is a
a G T in exon 14. This exon is a crucial brake on kinase activity • The mutation results in the substitution of a The mutation results in the substitution of a
valine at position 617 to a phenylalanine.
• Analysis demonstrates this is a highly conserved Analysis demonstrates this is a highly conserved
residue
• This mutation ubiquitous in PV, less often found hi
i
bi i
i Vl
f
f
d
in ET and MF.
FERM
SH2
Pseudokinase
JH2 Pseudokinase
Domain
V617F
KINASE
Campbell NEJM 2006
2005 Discoveries
2005 Discoveries
• DNA samples from patients with PV, ET or MF
DNA samples from patients with PV, ET or MF
• Sequencing performed in – Granulocyte subsets
Granulocyte subsets
– T‐Cell subsets
– DNA obtained from buccal swabs
• Mutation in JAK2 exon 14 discovered • In vitro and in vivo confirmatory experiments to prove gain of function and genotype‐phenotype relationship
In Vitro Data
In Vitro Data
• Grew
Grew cell lines that express the EPO Receptor and cell lines that express the EPO Receptor and
either JAK2 WT or JAK2 V617F
Data from Levine, Cancer CELL 2005
In vivo data
In vivo
• Mutant
Mutant JAK2 transfected into mouse bone JAK2 transfected into mouse bone
marrow cells
• Polycythemia and splenomegaly 28 days after Polycythemia and splenomegaly 28 days after
transplantation
• In different genetic backgrounds (murine), I diff
i b k
d (
i )
there were subtle differences in the phenotypes –
h
i
i.e. marked leukocytosis and k dl k
i
d
fibrosis in BALb/c mice
JAK2
mutational presence
JAK2 mutational presence
JAK2 Mutation Present
JAK
Mutation Present
95%
50%
50%
50%
20%
3%
PV
ET
PMF
RARS
Non‐classic de novo MPD
AML
Since then….
Since then….
• The
The same labs that began that investigation same labs that began that investigation
have discovered numerous other, less ubiquitous mutations
ubiquitous mutations
• Some are complementary to the JAK2
• Some are already in clinical practice
S
l d i li i l
i
Mutation
Mechanism?
Jak2V617F
Derails kinase regulatory activity; mutant allele burden appears
to coincide with disease activity; not-necessarily initiating event
Jak2, exon 12
Multiple mutations described. Induces erythrocytosis in mice if a
certain conserved region is disrupted
MPL
Encodes the thrombopoeitin receptor. Mutations seems to
disrupt negative regulatory elements in the cytosol of the
thrombopoeitin receptor – for a gain of function  JAK-STAT
JAK STAT
activation
TET2
With or without JAK2; biclonal disease described; ? Pathologic
impact
ASXL1
Aberrant RAR signaling
CBL
Wt CBL responsible for ubiquitination of kinases,
kinases including FLT3,
FLT3
mouse models implicate role in mast-cell disease
IDH1/IDH2 exon 4
Isocitrate dehydrogenase mutations. Role in decreased NADPH
production ?early events or develop during transformation
production.
IKZF1
19% of blast phase MPN JAK-STAT activation
Adapted from Tefferi, Leukemia, 2010
Novel Mutations
Novel Mutations
Mutation
Chromosome
Frequency
Jak2*
9p24
PV=96%;ET=55%;PMF=65%; blast phase MPN=50%
Jak2, exon
12*
9p24
PV=3%
MPL*
1p34
PV=rare;ET=3%;PMF=10%
TET2
4q24
PV=16%;ET=5%;PMF=17%; blast phase MPN=17%
PV=16%;ET=5%;PMF=17%; blast phase MPN=17%
ASXL1
20q11.1
Blast phase MPN=19%
CBL
11q23.3
PMF=6%
PMF
6%
IDH1/IDH2 exon 4
2q33.3/15q26 PMF=4%
.1
IKZF1
7p12
Blast phase MPN=19%
*affect lymphoid and myeloid cells
Adapted from Tefferi, Leukemia, 2010
Clonal or Oligoclonal?
Tefferi, Leukemia, 2010
So What?
So What?  Academically Interesting??
 Prognostic – Marker of Outcome in the absence of treatment??
 Predictive – Marker of Outcome in the presence of treatment??
 Therapeutic Target?
Topics to Cover
Topics to Cover
•
•
•
•
•
Overview of Diseases
Overview
of Diseases
Historical context
Therapy Up to Now
h
Therapy In the Future?
Pitfalls and Open Questions
Therapy: MPDs
Therapy: MPDs
• Polycythemia Vera
Polycythemia Vera
– Untreated patients‐ Median OS of 6‐18mo
– Treated patients –
Treated patients 10+ years
10+ years
– Goal: Prevent clotting
– Symptom Management: headache, weakness, S
t
M
t h d h
k
dizziness, epigastric distress, and pruritus.
Therapeutic Context
Therapeutic Context
Early part of the century
Early part of the century
Skeletal radiation, potassium arsenite, nitrogen mustard, busulfan, 6‐MP, etc.
Most common: P‐32 and Phlebotomy
Early retrospective studies showed benefit to P‐32
Polycythemia Study Group – founded 1967
Concern re toxicity of P‐32 therapy
Dissolved in 1987 after 14 studies. Last official publication in 1997
PVSG and others
PVSG and others
Study
Question
PVSG 01
PVSG‐01
Phlebotomy vs Phl
b t
Phlebotomy + P‐32 or Chlorambucil
Results
P
OS 12 6
OS=12.6yrs
P+C
9.1‐10.9 yrs
Conclusion: Increased AML in intervention arm – Reversal of conclusions from retrospective data
PVSG‐08
Hydrea vs Hydrea
vs
phlebotomy (NR)
Hydrea =less
Hydrea
less early thromboses
early thromboses
6.6 vs 14% at 2 years
5.9% risk of AML w/ hydrea
Conclusion: Hydroxyurea likely helpful to prevent clots in PV
Conclusion:
Hydroxyurea likely helpful to prevent clots in PV
Possible risk of AML – but this is retrospective, no randomized data
Therapy: Polycythemia Vera
Therapy: Polycythemia Vera
Phlebotomy: Safe and efficacious
Phlebotomy:
Safe and efficacious
Hydroxyurea
In high
In
high‐risk
risk patients better in preventing thrombosis
patients better in preventing thrombosis
Prospective studies show no single agent g
y
leukemogenicity
Low‐dose Aspirin
No excess bleeding risk
g
Positive antithrombotic properties
Therapy: ET
Therapy: ET
• Essential Thrombocythemia
Essential Thrombocythemia
– Most patients with ET enjoy a normal life expectancy without associated disease‐related complications – Goal: Prevent clotting and bleeding
– Symptom Management: vasomotor symptoms
• Aspirin
• For High‐risk patient (over 60, history of clot, Platelets>million)  Hydroxyurea
Therapy: ET
Therapy: ET
• Most
Most important randomized study
important randomized study
• UK study . Outcome: composite end point of stroke bleeding MI embolic event or death
stroke, bleeding, MI, embolic event or death
• Published in NEJM, 2005
• N=809, High‐Risk ET patients
• Randomized to Low‐Dose Aspirin
p
– + Hydrea
– +Anagrilide
Anagrilide
Therapy: PMF
Therapy: PMF
Differences – Less about preventing clot or bleeding.
L
b t
ti
l t bl di
– Much more symptomatic
– Much shorter life expectancy
M h h
lif
• Current drug therapy in PMF is neither curative nor essential for survival. • Risk stratification has been attempted –
DIPSS PLUS
DIPSS‐PLUS
Low ‐ 0 risk factors – Med OS: 15.4 yrs
Intermediate 1 ‐ 1 risk factor – Med OS: 6.5 yrs
y
Intermediate 2 – 2‐3 risk factors – Med OS: 2.9 yrs
High – 4+ risk factors – Med OS: 1.3 yrs 1.
2
2.
3.
4.
5.
6.
7.
8.
Thrombocytopenia; Pls <100K
Age>65
Hgn<10gm/dL
RBC transfusion requirement
Constitutional Symptoms
*unfavorable karyotype includes complex Circulating blasts >1%
karyotype or sole or two abnormalities that
Unfavorable karyotype*
Unfavorable karyotype
include +8, ‐7/7q‐, i(17q), inv(3), ‐5/5q‐, l d
/
(
)
( ) /
Leukocytosis >25,000
12p‐ or 11q23 rearrangement
“Conventional
Conventional therapies
therapies” ‐‐ PMF
• Symptom management: Anemia
Symptom management: Anemia
– ESAs, danazol, thalidomide, corticosteroids, androgens lenalidomide+Prednisone
androgens, lenalidomide+Prednisone
• Splenomegaly
– Hydrea, cladribine, thalidomide, lenalidomide
Hydrea cladribine thalidomide lenalidomide
– Splenectomy
– Radiotherapy
R di th
• Allo‐SCT capable of inducing CR
Allo‐SCT
Allo
SCT ‐‐ Myelofibrosis
 British Society of BMT (Stewart et al 2010)
et al 2010)  CIBMTR review (Ballen KK et al. 2010)
 N=51 PMF
 27=myeloablative (MA) (19
(MA) (19‐
54yrs)
 24= reduced‐intensity conditioning (RIC)(20‐64yrs)
 3yr OS was 44% for MA and 31% f
d
for RIC transplant
 Relapse rate = 15% (MA)46%, ((RIC))
 Nonrelapse mortality rates = 41% (MA) and 32% (RIC)
 Extensive chronic graft‐versus‐
host disease (GVHD) rates = 30%
host disease (GVHD) rates = 30% and 35%
 N=289 patients with PMF  Treatment
Treatment‐related
related mortality mortality
(TRM) was 27% at 1 year and 35% at 5 years.
 Five‐year OS were 37% and 30% in related and unrelated donor
in related and unrelated donor settings, respectively.
 Outcome did not appear to be favorably affected by RIC.
But now we have a gene, right??
But now we have a gene, right??
JAK 2 Inhibitor
JAK 2 Inhibitor
• Multiple under investigation
p
g
• Only one has been FDA approved: ruxolitinib
g
• Tested in MF – both JAK2 and JAK2 Negative
Ruxolitinib
Phase I/II : N Engl J Med 2010;363:1117‐27.
/
g
;
N=153; MF – JAK2+ and JAK2‐
15 mg twice daily; DLT ‐‐ reversible thrombocytopenia
Outcomes: Symptom improvement, spleen size. S
Secondary Outcomes: Survival, PFS
d
O t
S i l PFS
Confirmed in two Phase III studies  FDA approval
Confirmed in two Phase III studies 
FDA approval
N Engl J Med 2010;363:1117‐27.
JAK2 inhibitor Ruxolitinib
JAK2 inhibitor Ruxolitinib
Phase III study (COMFORT 1)
N= 309 patients
BID oral ruxolitinib (155 patients) vs placebo.
After median FU of 32 weeks
After median FU of 32 weeks
Ruxolitinib >> Placebo for spleen reduction
Ruxolitinib >> Placebo for symptom control
Reduction in proinflammatory cytokines (e.g. IL‐1RA, IL‐6, d
fl
k
(
TNF‐a, MIP‐1b) was documented and correlated with improvement in constitutional symptoms.
No change to JAK2V617F allele burden
No change to JAK2V617F allele burden
Little change to bone marrow pathology
Slight increase in Overall Survival reported at 2011 update
ASH, 2011
N Engl J Med 2010;363:1117‐27.
N Engl J Med 2010;363:1117‐27.
Ruxolitinib
•
•
•
•
•
12/2011 Survival Analysis:
12/2011
Survival Analysis:
Median follow up 52 weeks
13 ruxolitinib died
3
li i ib di d
24 placebo pts died A hazard ratio of death (95% CI) of 0.499 (
(0.254, 0.98) (p=0.0395) for ruxolitinib‐treated ,
) (p
)
pts.
Withdrawal Syndrome
Withdrawal Syndrome
• Clinical
Clinical problems in MF are due to the problems in MF are due to the
underlying abnormal myeloproliferation and a reactive cytokine‐driven
reactive, cytokine
driven inflammatory state.
inflammatory state
• There is an acute relapse of sx on drug discontinuation
• In 5 patients requiring hospitalization and even ICU stays
ICU
JAK2 inhibitors in PV and ET?
JAK2 inhibitors in PV and ET?
Drug
Disease
Phase
Results
INCB018242
PV and ET
–
refractory
to HU
Phase II, US
and Italy
sites
PV, n=34
97% with phlebotomy independence
59% with decrease in spleen size.
ET n=39
ET,
49% with normal plt counts
PV/ET
Phase II
↓ Spleen size (83%)
Improved pruritis (all)
Improved pruritis (all)
Reduction in phlebotomy (3/5)
5 thrombotic events
GI disturbance
2010 ASH
CEP701
Cephalon
2009 ASH
Back to the Patient
Back to the Patient
• JG
JG – Discussed JAK2 inhibitors with her. Discussed JAK2 inhibitors with her.
Because of her clotting risk and elevated platelets, I started her on hydroxyurea
• Have also discussed stem cell transplant with her, given her young age
• Fatigue, not splenomegaly is her primary complaint
• Real goal for her will be long‐term survival –
not symptom relief
Wrap Up
Wrap Up
•
•
•
•
•
Overview of Diseases
Overview
of Diseases
Historical context
Therapy Now
h
Therapy Soon? Pitfalls and Open Questions
`