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The FDA has granted accelerated approval to Bristol-Myers Squibb's Sprycel (dasatinib) Tablets for the treatment of adults in all phases of chronic myeloid leukemia (CML) (chronic, accelerated, or myeloid or lymphoid blast phase) with resistance or intolerance to prior therapy, including imatinib (Gleevec). Sprycel also received regular FDA approval for the treatment of adults with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) with resistance or intolerance to prior therapy.

At a median of 4.9 months of therapy with the investigational agent nilotinib (Tasigna, formerly AMN107), 92% of patients with treatment-resistant chronic phase Ph+ chronic myeloid leukemia (CML) achieved a complete hematologic response with normalization of white blood cell counts, and 35% had a complete cytogenetic response. All patient had shown resistance or intolerance to optimized imatinib (Gleevec) therapy

In a randomized open-label phase II clinical trial (START-R) presented at the 42nd Annual Meeting of the American Society of Clinical Oncology (abstract 6507), the oral multitargeted kinase inhibitor dasatinib achieved major cytogenetic responses in 35% of patients with chronic myeloid leukemia (CML) in chronic phase who had resistance or intolerance to imatinib (Gleevec) (aee also report on page 1 on FDA approval of dasatinib).

Molecular discoveries and clinical advances over the past few decades have made the treatment of chronic myeloid leukemia (CML) one of the great success stories of modern medicine. Before the 1980s, the focus was on maintaining normal white blood cell counts with agents such as hydroxyurea and busulfan. With the use of interferon, treatment strategies turned more toward cytogenetic remission. In 1998, targeted therapy was introduced to this setting with the first studies of imatinib mesylate. Since then, treatment objectives have shifted toward the attainment of molecular remission. In this review, we consider the variety of approaches to treating CML, efforts to minimize treatment failures, and possible future directions in therapy.

The FDA has granted priority review to dasatinib (BMS-354825), developed by Bristol-Myers Squibb, for treatment of imatinib (Gleevec)-resistant or refractory chronic myelogenous leukemia (CML) in adults.

Analysis of an early trial of a peptide vaccine, CMLVAX100, provides evidence of disease responses, including some complete molecular responses in patients with previously treated chronic myelogenous leukemia (CML), according to Monica Bocchia, MD, Department of Hematology, University of Siena, Italy. "Despite high rates of clinical and cytogenetic remission achieved by imatinib [Gleevec], most patients still have some degree of molecular residual disease," Dr. Bocchia said at the 47th Annual Meeting of the American College of Hematology (abstract 167). Furthermore, she noted that discontinuation of imatinib (Gleevec) usually results in recurrence of leukemia.

According to a study of late transplant outcomes for more than 6,500 chronic myeloid leukemia (CML) patients, those patients alive in remission 5 years after allogeneic hematopoietic cell transplantation (HCT) enjoy relatively low rates of subsequent disease relapse and death.

The past 20 years have brought significant advances in our ability to manage patients with non-Hodgkin's lymphoma. More precise classification systems, improvements in diagnosis and staging, and effective new treatments have improved outcomes and made cure a reasonable goal for many patients with these disorders.

First results of four phase II studies of the investigational oral, multitargeted kinase inhibitor dasatinib (BMS-354825) showed significant efficacy in imatinib (Gleevec) resistant and intolerant patients with chronic, accelerated, and blast phase (myeloid and lymphoid) chronic myeloid leukemia (CML).

Acute myelogenous leukemia (AML) is a disorder marked by infiltration of the bone marrow by abnormal hematopoietic progenitors. These cells are unable to differentiate in a normal fashion into myeloid, erythroid, and/or megakaryocytic cell lines and, unlike normal progenitors, are capable of infiltrating vital organs.

Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in the Western hemisphere, accounting for 30% of the leukemias in this population. The disease results from a clonal expansion of small B-lymphocytes. CLL always involves the bone marrow and peripheral blood. The disease also can be demonstrated in lymph nodes, liver, and spleen.

The curability of the aggressive, large-cell lymphomas was first convincinglyreported by Levitt et al in 1972.[1] Patients with “reticulum cellsarcoma” were treated with a regimen that came to be known as COMLA(cyclophosphamide, vincristine [Oncovin], methotrexate, leucovorin, cytarabine[Ara-C]). A more commonly quoted paper was published in 1975 by DeVita et aldescribing the cure of advanced “diffuse histiocytic lymphoma” with COPP (cyclophosphamide,vincristine [Oncovin], procarbazine, prednisone).[2] During the 1970sthe CHOP regimen (cyclophosphamide, doxorubicin HCl, vincristine [Oncovin],prednisone) was described by McKelvey et al[3]; it quickly became the mostwidely used treatment for the aggressive large-cell lymphomas. Patients treatedwith two cycles of CHOP beyond documentation of a complete remission wereoften cured.[4]

SAN DIEGO, California-An investigational drug, BMS-354825, overcame resistance to imatinib (Gleevec) in Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia (CML) patients in two small but dramatic phase I trials presented at the 46th Annual Meeting of the American Society of Hematology (ASH). After up to 9 months of treatment with BMS-354825, 31 of 36 chronic-phase patients (86%) had a complete hematological response, Charles L. Sawyers, MD, a Howard Hughes Medical Institute researcher at UCLA, reported (abstract 1). Among 29 patients who reached 3 months on treatment and could be evaluated for cytogenetic response, 13 responses were observed overall, including 8 major cytogenetic responses (28%), of which 5 were complete.

Chronic lymphocytic leukemia (CLL) is a clonal malignancy that results fromexpansion of the mature lymphocyte compartment. This expansion is aconsequence of prolonged cell survival, despite a low proliferative index. Theaffected lymphocytes are of B-cell lineage in 95% of cases, and the remainingcases involve T lymphocytes, likely representing a distinct disorder.

Bcl-2 functions as a key survival factor for lymphocytes and is highlyexpressed in a majority of non-Hodgkin's lymphomas. The ability ofoblimersen sodium (Genasense, previously known as G3139) to targetbcl-2 messenger RNA and decrease Bcl-2 protein levels has the potentialto enhance the activity of cytotoxic chemotherapy. Pretreatmentwith oblimersen followed by cyclophosphamide (Cytoxan, Neosar)markedly improved survival relative to single-agent cyclophosphamidein a murine xenograft model. Oblimersen has also enhanced the cytotoxicityof a variety of other agents against non-Hodgkin's lymphoma,including etoposide, rituximab (Rituxan), and alemtuzumab (Campath).An initial phase I study of oblimersen in non-Hodgkin's lymphomademonstrated modest single-agent activity. Recent reports suggest thatoblimersen may add to the activity of R-CHOP (rituximab-cyclophosphamide/doxorubicin/vincristine/prednisone) in previously untreatedmantle cell lymphoma and to rituximab alone in a variety of subtypesof relapsed non-Hodgkin's lymphoma. Additional studies in both treatment-naive and relapsed patients will define the role of oblimersen inthe treatment of non-Hodgkin's lymphoma.

The field of radioimmunotherapy for the treatment of non-Hodgkin'slymphoma (NHL) has advanced significantly over the past decade, andseveral radioimmunoconjugates are being tested in clinical trials. Twoof these antibodies target CD20: yttrium-90 (Y-90)-labeled ibritumomabtiuxetan (Zevalin) and tositumomab/iodine-131 (I-131)-labeledtositumomab (Bexxar). Other agents target either CD22 (Y-90epratuzumab) or human leukocyte antigen (HLA)-DR (I-131 Lym-1),respectively. In February 2002, Y-90-labeled ibritumomab tiuxetanbecame the first radioimmunoconjugate to be approved by the US Foodand Drug Administration (FDA) for the treatment of cancer.Tositumomab/I-131 tositumomab was approved in June 2003. Thus,two radioimmunoconjugates have been approved for the treatment ofNHL. Both agents, when administered as a single dose, have producedimpressive tumor response rates with an acceptable toxicity profile. Themain side effect is reversible myelosuppression. Radioimmunotherapyproduces overall response rates of approximately 80% in patients withlow-grade lymphomas, and 25% to 30% of patients achieve a completeremission. Lower response rates (approximately 40%) have been reportedin patients with large-cell lymphomas. This review discusses theclinical trials of radioimmunotherapeutic agents for NHL that demonstratedtheir safety and efficacy and outlines the current status of theseagents.

SAN DIEGO-In the IRIS study, newly diagnosed chronic myelogenous leukemia (CML) patients who crossed over from interferon (IFN)-alfa plus cytarabine (ara-C) to imatinib mesylate (Gleevec) and achieved a complete cytogenetic response (CCR = elimination of Ph+ cells), had reductions in bcr-abl similar to those on first-line imatinib, according to a presentation at the 45th Annual Meeting of the American Society of Hematology (ASH abstract 635). Their probability of achieving a CCR, is somewhat diminished, however, compared with those treated with first-line imatinib, said Jerald P. Radich, MD, Fred Hutchinson Cancer Research Center, Seattle.

SAN DIEGO- Doubling the standard dose of imatinib mesylate (Gleevec) to 800 mg provided more complete cytogenetic responses (CCRs) more quickly with higher rates of PCR (polymerase chain reaction) negativity than the standard dose (400 mg) in patients with previously untreated early-stage chronic myeloid leukemia (CML).

Together, parts 1 and 2 of thearticle by Drs. Wilson andSmith on the “Management ofMycosis Fungoides” serve as an excellentreference for the diagnosis andmanagement of this subtype of cutaneousT-cell lymphoma. Part 1, whichdeals with the diagnosis, staging, andprognosis of mycosis fungoides, appearedin the September 2003 issue ofthis journal. Part 2, which deals withtreatment, appears in the current issue.The article is a concise overviewof the numerous treatment strategiesand specific treatments available forvarious stages and presentations ofmycosis fungoides.