LBH589 Plus Decitabine for Myelodysplastic Syndromes (MDS) or Acute Myeloid Leukemia (AML)

To address the need for less toxic, more effective treatments for older patients with advanced MDS and AML, the purpose of this Phase 1-2 single institution study is to evaluate the safety and efficacy of LBH 589 and decitabine administered in combination.

Decitabine is an epigenetic modifier of gene expression that has been shown to be well-tolerated in this population at the dose schedule proposed in this study, with reasonable efficacy. Although its precise mechanism of action is incompletely understood, it is postulated to work by reactivating the expression of key tumor suppressor genes silenced in tumor cells by reversing a pattern of hypermethylation of promotor elements.

LBH389 is likewise an epigenetic modifier that inhibits the deacetylation of both histones and non-histone proteins, including HSP90 and p53. Although clinical experience with LBH589 in AML is limited, aberrant histone deacetylase activity has been previously shown to play a significant role in the pathogenesis of AML. The addition of LBH589 to a decitabine regimen of previously established efficacy and tolerability will allow us to evaluate the hypothesis that two epigenetic modifiers that are believed to work through distinct mechanisms of action may act together to improve the responses of patients treated with decitabine alone, without significant additional toxicity.

Inclusion criteria

• AML (except t(15;17), inv(16) or t(8;21) and variants) or high risk MDS (IPSS Int-2 or High) diagnosed according to WHO criteria (see Appendix 1)
• Age ≥ 60 years old
• Not a candidate for allogeneic stem cell transplantation within next 12 weeks
• Ability to provide written informed consent, obtained prior to participation in the study and any related procedures being performed
• Patients must meet the following laboratory criteria:
• Serum albumin ≥ 3 g/dL
• Aspartate aminotransferase (AST)/SGOT and alanine aminotransferase (ALT)/SGPT ≤ 2.5 x upper limit of normal (ULN) ) or ≤ 5.0 x ULN if the transaminase elevation is due to leukemic involvement
• Serum bilirubin ≤ 1.5 x ULN
• Serum creatinine ≤ 1.5 x ULN or 24-hour creatinine clearance ≥ 50 ml/min
• Serum potassium ≥ lower limit of normal (LLN)
• Serum phosphorus ≥ LLN
• Serum total calcium (corrected for serum albumin) or serum ionized calcium ≥ LLN
• Serum magnesium ≥ LLN, thyroid stimulating hormone (TSH) and free thyroxine (T4) within normal limits (WNL) (patients may be on thyroid hormone replacement)
• Baseline MUGA or ECHO must demonstrate left ventricular ejection fraction (LVEF) ≥ the lower limit of the institutional normal.
• Eastern Cooperative Oncology Group (ECOG) Performance Status of ≤ 2

Exclusion criteria

• Prior treatment for MDS / AML with Histone deacetylase (HDAC) inhibitor or hypomethylating agent (e.g., Decitabine, azacitidine etc.)
• Active central nervous system (CNS) involvement with MDS/AML
• Impaired cardiac function including any one of the following:
• Screening electrocardiogram (ECG) with a QTc > 450 msec confirmed by central laboratory prior to enrollment to the study
• Patients with congenital long QT syndrome
• History of sustained ventricular tachycardia
• Any history of ventricular fibrillation or torsades de pointes
• Bradycardia defined as heart rate < 50 beats per minute. Patients with a pacemaker and heart rate ≥ 50 beats per minute are eligible.
• Patients with a myocardial infarction or unstable angina within 6 months of study entry
• Congestive heart failure (NY Heart Association class III or IV)
• Right bundle branch block and left anterior hemiblock (bifasicular block)
• Uncontrolled hypertension
• Concomitant use of drugs with a risk of causing torsades de pointes
• Patients with unresolved diarrhea > CTCAE grade 1
• Impairment of gastrointestinal (GI) function or GI disease that may significantly alter the absorption of oral LBH589
• Other concurrent severe and/or uncontrolled medical conditions
• Patients who have received chemotherapy or any investigational drug < 2 weeks or hydroxyurea < 48 hours prior to starting study drug or who have not recovered from side effects of such therapy.
• Concomitant use of any anti-cancer therapy or radiation therapy
• Male patients whose sexual partners are women of child bearing potential (WOCBP) not using effective birth control
• Patients with known positivity for human immunodeficiency virus (HIV) or hepatitis C; baseline testing for HIV and hepatitis C is not required
• Patients with any significant history of non-compliance to medical regimens or with inability to grant a reliable informed consent
• Patients who will need valproic acid for any medical condition during the study or within 5 days prior to first LBH589 treatment
• Patients who have received targeted agents within 2 weeks or within 5 half-lives of the agent and active metabolites (whichever is longer) and who have not recovered from side effects of those therapies
• Patients who have undergone major surgery ≤ 4 weeks prior to starting study drug or who have not recovered from side effects of such therapy.