Azacitidine Plus Deferasirox (ICL670) in Higher Risk Myelodysplastic Syndromes (MDS)

A PHASE II STUDY OF Azacitidine Plus Deferasirox (ICL670) in Higher Risk Myelodysplastic Syndromes (MDS)

Myelodysplastic syndromes are common blood disorders that can affect as many as one in 1000 Canadians over the age of 65. They are characterized by low blood counts that require frequent blood transfusions. The development of iron overload in these patients is inevitable. The iron deposits in vital organs such as the heart and the liver and can lead to organ dysfunction. Deferasirox is a well-studied drug that helps remove iron from the body. Most people with this disorder die due to progression of their disease to acute leukemia through multiple mechanisms. Iron overload in patients with myelodysplastic syndromes has been shown to be associated with shorter survival, and potentially a higher chance of leukemia. In a certain sub-group of higher risk patients, the drug azacitidine has been shown to decrease the chance of progression to leukemia and death from it. Thus, it is presently the standard of care for these patients. However, 50% of higher risk patients are still unresponsive to this medication, leaving a large group of patients for which other treatment options are emergently needed. Given that a large proportion of higher risk MDS patients fail to respond to azacitidine, and the evidence that iron deposition may lead to increased leukemic transformation, we would like to study whether iron removal from the body with deferasirox potentiates azacitidine in its effects on overall survival, as well as the chance of leukemia transformation. This question needs to be addressed in a randomized controlled trial, and the first step is a preliminary study to determine if the combination of azacitidine and deferasirox has any biologic effect. This study will determine whether this combination leads to blood count improvement over azacitidine alone. If this drug combination ultimately proves more useful than azacitidine alone with respect to survival, this has the potential to impact the care of a large proportion of patients with myelodysplastic syndromes.

Patients with stable disease after 6 cycles of AZA with higher risk MDS will be randomized to either standard of care (continued AZA until progression ) or AZA + defasirox. Primary endpoint is augmented response rate by the addition of deferasirox

Inclusion Criteria:

• Adults >18 yrs of age
• WHO defined MDS with Higher risk MDS (IPSS int-2/high)
• Azacitidine X at least 6 cycles with no hematologic improvement/no disease progression as per IWG 2006 criteria
• Ferritin >500 µg/L
• If transfusion independent, must have Hb <110 g/L OR Neutrophils < 1,000/mL OR Platelets < 100,000/mL
• ECOG ≤2
• CrCl >40 ml/min

Exclusion Criteria:

• Increased ALT (>300 U/L)
• Uncontrolled infection
• HIV+
• Pregnant or breast-feeding
• Previous and concurrent iron chelation
• Concurrent use of hematopoietic growth factors including erythropoietin, darbepoietin and granulocyte colony stimulating factor
• Concurrent use of other disease modifying agents including cytotoxic chemotherapy, histone deacetylase inhibitors, other hypomethylating agents or lenalidomide