myelodysplasia: background and current treatment approaches in australia michael dickinson,...
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Myelodysplasia: background and current treatment approaches in Australia
Michael Dickinson, HaematologistPeter MacCallum Cancer Centre
Overview
• What is myelodysplasia? How does it affect you?
• How doctors think about the disease and the words we use?
• What on earth is epigenetics?• Treatments – When, what, how,
practicalities…. Azaciditine & lenalidomide (MDS)
• Trials
Understanding myelodysplasia isn’t easy!
Effects of MDS
• Low white cell count (neutropenia)• Low red cell count (anaemia)• Low platelet count (thrombocytopenia)• In some patients there is a risk of
leukaemia
What is myelodysplasia (MDS)?
• “clonal disorder of the bone marrow”• MDS is a kind of cancer
Myeloproliferative disorders
• Also a clonal disorder• Large spleen &/or liver• High white cell count, red cell
count, or platelets
Clones.
Causes
?
DIAGNOSIS
Basic Diagnostic Evaluation FBE, film
Bone marrow aspiration and biopsy
Cytogenetics
(flow cytometry)
Additional tests
Vitamin levels (B12, folate, iron and ferritin)
EPO (erythropoietin)
Other eg causes anaemia
Diagnosis
• Low counts• The way the precursors look under the
microscope• More than the normal amount of blasts.
What are “blasts”?
Classification of MDS - marrow
Percentage of blasts
Cytogenetics
Prognosis - IPSS
Prognosis – R-IPSS
TREATMENT - MDS
Managing marrow failure:Transfusion
• Red cells• Platelets• ?white cells
For many people people, transfusion is no problem but sometimes there are complications
• Inconvenient• Platelet transfusion refractoriness
“platelet antibodies”• Red cell transfusion refractoriness
“red cell antibodies”• Rate of transmitted disease is very
low – ARCBS keeps blood safe.
Iron overload
• Haemoglobin contains iron
• Ferritin > 1000 (20units)• Evidence of iron overload
Iron overload
Exjade
• Iron chelator• Orally available • Generally well tolerated• Some side effects
Median Change in Serum Ferritin Levels from Baseline (By Initial Dose Group)
−1500
−1000
-500
0
500
1000
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42
Time Since Start of Treatment (months)
Med
ian C
han
ge in S
eru
m F
err
itin
Levels
(µg/L
)
0
Core Extension
5–10 (n = 227) 20 (n = 182) 30 (n = 243)Initial deferasirox dose, mg/kg/day
Studies 106–109With permission from Porter J, et al. ASH 2007. December 8-10, 2007. Poster 968.
Other treatments
• Erythropoietin in renal failure• Immunosuppression in rare
cases
New treatments for MDS
• Big steps forward• Azacitidine (Vidaza)• Lenalidomide (for 5q-) (Revlimid)• New trials
Epigenetics
• Things that change the way genes are expressed without changing the DNA code.
• Histone modification
• DNA methylation
Azacitidine (Vidaza)
• Epigenetic drug• “low dose chemotherapy”
Azacitidine (VIDAZA)
• Subcutaneous injection 7 days each month• Given as a maintenance therapy• PBS funded - >10% blasts, <30% blasts• Reduces the risk of progression to
leukaemia• Reduces transfusion dependence
Better than “best supportive care” and conventional chemotherapy
Key issues around azacitidine
• Initial cytopenia cycle 1-2 (and sometimes ongoing)
• Response at 4 cycles.• 7 consecutive days of therapy• Skin irritation• Azacitidine breaks conventional
thinking.• PBS approval
Example of patient: 5-azacitidine
Lenalidomide (Revlimid)
• Tablet - well tolerated. Best evidence 5q-disease
• Available in Australia but not funded for myelodysplasia
• Expensive• Reduces transfusion requirements but not a
treatment for blasts• Side effects include low neutrophils and
platelets• Doesn’t work in everyone• In high doses maybe anti-leukaemic
Other supportive things
• Antibiotics – posaconazole (noxafil)
Allotransplantation
• Mini-allo transplant• Uncertainty about timing
Why MDS studies are challenging
• Toxicity of novel agents• Measuring responses• Leukemic transformation is
part of the natural history• Drug development is also a
business
Trials
• MDS4 (Aza-rev)
Trials
• MDS4 (Aza-rev)• Aza-eltrombopag
Trials
• MDS4 (Aza-rev)• Aza-eltrombopag• Aza-panobinostat• Phase 1 studies• International studies
– Eltrombopag– Estybon (rigosertib, ON 01910.NA) – cell cycle
inhibitor via polo-like kinase inhibition– Tosedostat – aminopeptidase inhibitor– HDAC inhibitor combination studies
Conclusions
• Myelodyspasia is heterogenous (everybody’s case is different)
• Many advances in the last few years• Much progress in supportive care
• Victoria is a great place to be!