New Developments in Acute Myelogenous Leukemia (AML)

  • Control of Infection - Because leukemia patients are vulnerable to bacterial and fungal infections, research is ongoing to develop improved methods for the prevention and treatment of infections in patients with leukemia.

  • Targeted CD33 Therapy - Approximately 90% of AML blast cells express a protein on their surface called CD33 (myeloid-specific antigen). Targeted CD33 has recently emerged as an exciting new strategy for the treatment of acute myelogenous leukemia. Examples include:

    • Gemtuzumab ozogamicin (Mylotarg) - This is a monoclonal antibody directed against the CD33 antigen that was approved in May 2000 for the treatment of relapsed acute myelogenous leukemia in patients 60 years or older. Studies are underway to evaluate the efficacy of gemtuzumab-ozogamicin in older patients with newly diagnosed acute myelogenous leukemia.

    • HuM195 - This is a monoclonal antibody that was developed by researchers at the Memorial Sloan-Kettering Cancer Center (New York, NY) that is active against acute promyelocytic leukemia (APL)

  • Farnesyl Transferase Inhibitors - Mutations in the RAS oncogenes are sometimes observed in acute myelogenous leukemia. It has also been hypothesized that RAS oncogenes may be activated or "turned-on" in AML. A new class of drugs called farnesyl transferase inhibitors (FTI's) are being developed to prevent the activation of RAS oncogenes as a novel treatment for acute myelogenous leukemia.

  • Other new approaches for the treatment of acute myelogenous leukemia that are currently being investigated include:

    • Hypomethylating agents such as decitabine
    • Troxacitabine - an L-nucleoside compound that has been shown to have anticancer activity
    • Anti-VEGF inhibitors - Several studies have shown that angiogenesis, the production of new blood vessels, is enhanced in acute myelogenous leukemia. Anti-VEGF inhibitors are antibodies that are designed to inhibit angiogenesis by interfering with vascular endothelial growth factor (VEGF) that is thought to play an important role in angiogenesis.

  • The role of viruses in the development of leukemia and other cancers is being studied.

  • Immunotherapy is an area of great promise in treating leukemia, especially for older persons who do not tolerate aggressive chemotherapy regimens as well. Antibodies are being created and vaccines are being developed which attack leukemic cells.

  • The use of therapy which is targeted to mutations in leukemic cells and the biochemical molecules and pathways which result from these genetic changes. For example, one relatively common mutation is known as an "internal tandem duplication of the FLT 3 gene". This mutation results in abnormal function of an enzyme known as a kinase. Several drugs have been developed that inhibit this enzyme. These drugs are analogous to iminitab mesylate (Gleevec) that has been used successfully in chronic myeloid leukemia ("CML"). Although preliminary data suggest that the drugs targeting the FLT3-altered kinase are unlikely to be as successful as Gleevec has been in CML, they may be more useful when combined with chemotherapy.

  • Using less intense therapy to prepare patients for stem cell transplantation and capitalizing upon donor immunologic cells attacking residual leukemic cells which remain the recipient (non myeloablative transplantation)

  • Arsenic trioxide is very effective at inducing remission in patients with relapsed APL.

  • Information regarding ongoing clinical studies in your area can be obtained at the Clinical Trials Listing Service at http://www.centerwatch.com or http://www.clinicaltrials.gov.