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Biomedical subjects

Deborah Thomas

Publications and source records attributed to Deborah Thomas.

At least 19 recordsLinked to original sources

Primary myelofibrosis (PMF), post polycythemia vera myelofibrosis (post-PV MF), post essential thrombocythemia myelofibrosis (post-ET MF), blast phase PMF (PMF-BP): Consensus on terminology by the international working group for myelofibrosis research and treatment (IWG-MRT).

The International Working Group for Myelofibrosis Research and Treatment (IWG-MRT) is comprised of hematologists, hematopathologists, and laboratory scientists and its main goal is to provide a forum for scientific exchange and collaboration. During its first general meeting in April 2006, the IWG-MRT established uniform treatment response criteria for chronic idiopathic myelofibrosis (CIMF); also known as agnogenic myeloid metaplasia (AMM), myelofibrosis with myeloid metaplasia (MMM), and many other names in the hematologic literature. This document summarizes the proceedings from the second meeting of the IWG-MRT, in November 2006, where the group discussed and agreed to standardize the nomenclature referring to CIMF: (i) the term primary myelofibrosis (PMF) was chosen over several other designations including CIMF, AMM, and MMM, (ii) myelofibrosis that develops in the setting of either polycythemia vera (PV) or essential thrombocythemia (ET) will be referred to as post-PV MF and post-ET MF, respectively, and (iii) "leukemic" transformation will be recognized as blast phase disease (PMF-BP, post-PV/ET MF in blast phase).

Blast Crisis↗

The haematopoietic cell transplantation comorbidity index score is predictive of early death and survival in patients over 60 years of age receiving induction therapy for acute myeloid leukaemia.

The haematopoietic cell transplantation comorbidity index (HCTCI) predicts nonrelapse mortality and overall survival (OS) post-stem cell transplantation. HCTCI scores were assessed in 177 patients over 60 years of age receiving acute myeloid leukaemia (AML) induction therapy. HCTCI score was 0 in 22% of patients, 1-2 in 30%, and > or =3 in 48%. In patients with scores of 0, 1-2, or > or =3, early death rates were 3%, 11% and 29% (P < 0.001) respectively; median OS was 45, 31 and 19 weeks (P = 0.04) respectively. The HCTCI score is predictive of early death rates and OS in older patients receiving AML induction therapy.

Acute Disease↗

Lenalidomide in the myelodysplastic syndrome with chromosome 5q deletion.

BACKGROUND: Severe, often refractory anemia is characteristic of the myelodysplastic syndrome associated with chromosome 5q31 deletion. We investigated whether lenalidomide (CC5013) could reduce the transfusion requirement and suppress the abnormal 5q31- clone in patients with this disorder. METHODS: One hundred forty-eight patients received 10 mg of lenalidomide for 21 days every 4 weeks or daily. Hematologic, bone marrow, and cytogenetic changes were assessed after 24 weeks of treatment by an intention-to-treat analysis. RESULTS: Among the 148 patients, 112 had a reduced need for transfusions (76%; 95% confidence interval [CI], 68 to 82) and 99 patients (67%; 95% CI, 59 to 74) no longer required transfusions, regardless of the karyotype complexity. The response to lenalidomide was rapid (median time to response, 4.6 weeks; range, 1 to 49) and sustained; the median duration of transfusion independence had not been reached after a median of 104 weeks of follow-up. The maximum hemoglobin concentration reached a median of 13.4 g per deciliter (range, 9.2 to 18.6), with a corresponding median rise of 5.4 g per deciliter (range, 1.1 to 11.4), as compared with the baseline nadir value before transfusion. Among 85 patients who could be evaluated, 62 had cytogenetic improvement, and 38 of the 62 had a complete cytogenetic remission. There was complete resolution of cytologic abnormalities in 38 of 106 patients whose serial bone marrow samples could be evaluated. Moderate-to-severe neutropenia (in 55% of patients) and thrombocytopenia (in 44%) were the most common reasons for interrupting treatment or adjusting the dose of lenalidomide. CONCLUSIONS: Lenalidomide can reduce transfusion requirements and reverse cytologic and cytogenetic abnormalities in patients who have the myelodysplastic syndrome with the 5q31 deletion. (ClinicalTrials.gov number, NCT00065156 [ClinicalTrials.gov].).

Adult↗

Phase I/II study of the mammalian target of rapamycin inhibitor everolimus (RAD001) in patients with relapsed or refractory hematologic malignancies.

PURPOSE: Everolimus (RAD001, Novartis), an oral derivative of rapamycin, inhibits the mammalian target of rapamycin (mTOR), which regulates many aspects of cell growth and division. A phase I/II study was done to determine safety and efficacy of everolimus in patients with relapsed or refractory hematologic malignancies. EXPERIMENTAL DESIGN: Two dose levels (5 and 10 mg orally once daily continuously) were evaluated in the phase I portion of this study to determine the maximum tolerated dose of everolimus to be used in the phase II study. RESULTS: Twenty-seven patients (9 acute myelogenous leukemia, 5 myelodysplastic syndrome, 6 B-chronic lymphocytic leukemia, 4 mantle cell lymphoma, 1 myelofibrosis, 1 natural killer cell/T-cell leukemia, and 1 T-cell prolymphocytic leukemia) received everolimus. No dose-limiting toxicities were observed. Grade 3 potentially drug-related toxicities included hyperglycemia (22%), hypophosphatemia (7%), fatigue (7%), anorexia (4%), and diarrhea (4%). One patient developed a cutaneous leukocytoclastic vasculitis requiring a skin graft. One patient with refractory anemia with excess blasts achieved a major platelet response of over 3-month duration. A second patient with refractory anemia with excess blasts showed a minor platelet response of 25-day duration. Phosphorylation of downstream targets of mTOR, eukaryotic initiation factor 4E-binding protein 1, and/or, p70 S6 kinase, was inhibited in six of nine patient samples, including those from the patient with a major platelet response. CONCLUSIONS: Everolimus is well tolerated at a daily dose of 10 mg daily and may have activity in patients with myelodysplastic syndrome. Studies of everolimus in combination with therapeutic agents directed against other components of the phosphatidylinositol 3-kinase/Akt/mTOR pathway are warranted.

Adaptor Proteins, Signal Transducing↗

Lenalidomide therapy in myelofibrosis with myeloid metaplasia.

We present results of 2 similarly designed but separate phase 2 studies involving single-agent lenalidomide (CC-5013, Revlimid) in a total of 68 patients with symptomatic myelofibrosis with myeloid metaplasia (MMM). Protocol treatment consisted of oral lenalidomide at 10 mg/d (5 mg/d if baseline platelet count < 100 x 10(9)/L) for 3 to 4 months with a plan to continue treatment for either 3 or 24 additional months, in case of response. Overall response rates were 22% for anemia, 33% for splenomegaly, and 50% for thrombocytopenia. Response in anemia was deemed impressive in 8 patients whose hemoglobin level normalized from a baseline of either transfusion dependency or hemoglobin level lower than 100 g/L. Additional treatment effects in these patients included resolution of leukoerythroblastosis (4 patients), a decrease in medullary fibrosis and angiogenesis (2 patients), and del(5)(q13q33) cytogenetic remission accompanied by a reduction in JAK2(V617F) mutation burden (1 patient). Grade 3 or 4 adverse events included neutropenia (31%) and thrombocytopenia (19%). We conclude that lenalidomide engenders an intriguing treatment activity in a subset of patients with MMM that includes an unprecedented effect on peripheral blood and bone marrow abnormalities.

Administration, Oral↗

Proteomic-based prediction of clinical behavior in adult acute lymphoblastic leukemia.

BACKGROUND: Response in adult acute lymphoblastic leukemia (ALL) can be achieved in a majority of patients. However, unlike pediatric ALL, recurrence is common in adult ALL, and the ability to predict at an early stage which patients are most likely to experience recurrence may help in devising new therapeutic approaches to prevent recurrence. METHODS: Peripheral blood plasma from 57 patients with confirmed ALL was obtained before induction therapy for proteomic analysis. Follow-up continued for a median period of 71 weeks. For each plasma sample, 4 fractions eluted from a strong anion column were applied to 3 different ProteinChip array surfaces, and 12 surface-enhanced laser desorption/ionization (SELDI) spectra were generated. Peaks that correlated with recurrence were identified and decision trees were constructed and evaluated, using only 2 peaks per predictive tree. RESULTS: The best decision trees provided strong positive prediction of recurrence, with correct predictions 84% to 92% of the time, whereas negative prediction of patients who did not experience recurrence was less robust, with 62% to 74% accuracy. Prediction of recurrence was independent of cytogenetics, bone marrow blast count, lactate dehydrogenase, beta-2-microglobulin, or surface markers. Positive prediction of L3 morphological classification was achieved in 80% of test cases. CONCLUSIONS: Peripheral blood plasma is adequate to predict clinical behavior in ALL patients irrespective of the percentage of bone marrow blasts. Proteomic analysis of plasma offers a useful approach for profiling patients with ALL.

Adolescent↗

Triapine and cytarabine is an active combination in patients with acute leukemia or myelodysplastic syndrome.

Triapine, an iron chelator and a potent inhibitor of ribonucleotide reductase, has significant anti-leukemia activity. A phase I study of Triapine in combination with ara-C was conducted in 32 patients with refractory acute leukemia and high-risk MDS. Triapine (105 mg/m2/day 6-h infusion) was followed immediately by ara-C [100 (n=4), 200 (n=6), 400 (n=7), or 800 (n=8)mg/m2/day] as an 18-h infusion for 5 consecutive days. Dose-limiting toxicities (DLTs) were observed at the 800 mg/m2 ara-C dose level (one patient each with grade 4 mucositis; grade 4 neutropenic colitis, sepsis; grade 4 neuropathy; and grade 4 hyperbilirubinemia). Therefore, the study was amended to include an ara-C dose level of 600 mg/m2/day, no DLTs occurred in seven patients treated at this dose level. Mean Triapine C(max) and AUC were 1.13 microg/mL and 251.5 minmicrog/mL. Of 31 evaluable patients, 4 (13%) (3 AML, 1 Ph+ALL) achieved a CR (1 at a dose of 800 mg/m2; 2 at 600 mg/m2; 1 at 200mg/m2). The recommended phase II regimen is Triapine 105 mg/m2/day followed by ara-C 600 mg/m2/day for 5 consecutive days every 3-6 weeks.

Acute Disease↗

A retrospective comparison of three sequential groups of patients with Recurrent/Refractory chronic lymphocytic leukemia treated with fludarabine-based regimens.

BACKGROUND: Combining therapeutics with single-agent activity has improved treatment for patients with many malignancies. Debate continues about the impact of treatment on survival in patients with chronic lymphocytic leukemia (CLL). Purine analogues are the most active agents for treatment of patients with CLL. Recently, it was shown that a chemoimmunotherapy regimen combining fludarabine (F), cyclophosphamide (C), and rituximab (R) (FCR) was very effective in treating patients with recurrent and/or refractory CLL. The objective of the current analysis was to determine whether improvements in treatment have had an impact on survival for patients with CLL. METHODS: Three nonoverlapping, sequential groups of patients enrolled on Phase II studies who received treatment with F (n = 251 patients), FC (n = 111 patients), or FCR (n = 143 patients) were analyzed. Pretreatment characteristics, responses to treatment, and overall survival were compared. RESULTS: Patients who were treated with FCR had a higher complete remission rate compared with patients who were treated with combined F and C or with F alone. Statistically significantly longer estimated median survival was noted for patients who received FCR. A Cox proportional hazards, multivariable model for overall survival that included all patients (n = 505) showed that patients who received FCR had longer survival (P < 0.0001) after adjusting for other significant (P < 0.05) pretreatment characteristics, including age, hemoglobin, beta-2 microglobulin, and the number of prior treatments. CONCLUSIONS: The results of this retrospective comparison of patients with recurrent and refractory CLL indicated a higher complete remission rate and the longest estimated survival for patients who were treated with FCR, providing the basis for randomized clinical trials of this regimen.

Adult↗

Validation of the European Prognostic Index for younger adult patients with acute myeloid leukaemia in first relapse.

In order to validate the European Prognostic Index (EPI) for patients <or=60 years with acute myeloid leukaemia in first relapse, a cohort of 599 such patients, treated between 1980 and 2004 at the MD Anderson Cancer Center, were assessed using this prognostic index. Three risk groups were defined: favourable, 76 patients (13%) [Overall survival (OS), 64% at 1 year, 22% at 5 years]; intermediate, 137 patients (23%) (OS, 38% at 1 year, 12% at 5 years); and poor, 386 patients (64%) (OS, 17% at 1 year 6% at 5 years). The EPI is reproducible and useful.

Acute Disease↗

Advances in the therapy of chronic idiopathic myelofibrosis.

The molecular basis of chronic idiopathic myelofibrosis (CIMF) has remained elusive, thus hampering the development of effective targeted therapies. However, significant progress regarding the molecular mechanisms involved in the pathogenes is of this disease has been made in recent years that will likely provide ample opportunity for the investigation of novel therapeutic approaches. At the fore front of these advances is the discovery that 35%-55% of patients with CIMF harbor mutations in the Janus kinase 2 tyrosine kinase gene. Until very recently, the management of patients with CIMF involved the use of supportive measures, including growth factors, transfusions, or interferon, and the administration of cyto-reductive agents, such as hydroxyurea and anagrelide. However, several trials have demonstrated the efficacy of antiangiogenic agents alone or in combination with corticosteroids. In addition, the use of reduced-intensity conditioning allogeneic stem cell transplantation has resulted in prolonged survival and lower transplant-related mortality.

Antineoplastic Agents↗

Phase I study of cloretazine (VNP40101M), a novel sulfonylhydrazine alkylating agent, combined with cytarabine in patients with refractory leukemia.

PURPOSE: Cloretazine (VNP40101M) is a novel sulfonylhydrazine alkylating agent with significant antileukemia activity. A phase I study of cloretazine combined with cytarabine (1-beta-d-arabinofuranosylcytosine, ara-C) was conducted in patients with refractory disease. DESIGN: Ara-C was given i.v. at a fixed dose of 1.5 gm/m(2)/d by continuous infusion for 4 days (patients ages <65 years at time of diagnosis) or 3 days (patients ages > or =65 years). Cloretazine was given i.v. over 15 to 60 minutes on day 2 at a starting dose of 200 mg/m(2), with escalation in 100 mg/m(2) increments in cohorts of three to six patients until a maximum tolerated dose was established. The DNA repair enzyme O(6)-alkylguanine DNA alkyltransferase (AGT) was measured at baseline. RESULTS: Forty patients, including 32 with acute myeloid leukemia, received 47 courses of treatment. Complete responses were seen at cloretazine dose levels of > or =400 mg/m(2) in 10 of 37 (27%) evaluable patients, and in this patient subset, AGT activity was significantly lower in patients that responded to treatment than in patients who did not (P < or = 0.027). Dose-limiting toxicities (gastrointestinal and myelosuppression) were seen with 500 and 600 mg/m(2) of cloretazine combined with the 4-day ara-C schedule but not seen with the 3-day schedule. CONCLUSION: The recommended cloretazine dose schedule for future studies is 600 mg/m(2) combined with 1.5 gm/m(2)/d continuous infusion of ara-C for 3 days. The cloretazine and ara-C regimen has significant antileukemic activity. AGT activity may be a predictor of response to cloretazine.

Adult↗

Phase 1 study of ABT-751, a novel microtubule inhibitor, in patients with refractory hematologic malignancies.

PURPOSE: ABT-751 is an oral antimitotic agent that binds to the colchicine site on beta-tubulin. A phase 1 study was conducted to determine the maximum tolerated dose and toxicities of ABT-751 in patients with advanced myelodysplastic syndrome and relapsed or refractory acute leukemias. STUDY DESIGN: Thirty-two patients were treated: nine with 100 (n = 3), 125 (n = 3), or 150 mg/m(2) (n = 3) of ABT-751 given orally once daily for 7 days every 3 weeks and 23 with 75 (n = 3), 100 (n = 3), 125 (n = 5), 150 (n = 5), 175 (n = 3), or 200 mg/m(2) (n = 4) of ABT-751 given orally once daily for 21 days every 4 weeks. Consenting patients had pharmacogenetic sampling and enumeration of circulating endothelial cells (CEC). RESULTS: Dose-limiting toxicity consisted of ileus in one patient at 200 mg/m(2), with a subsequent patient developing grade 2 constipation at the same dose level. One patient with relapsed acute myelogenous leukemia achieved a complete remission that was sustained for 2 months. Four other patients had transient hematologic improvements, consisting of a decrease in peripheral blood blasts and improvements in platelet counts. CEC number was reduced in three patients with a concomitant reduction in peripheral blasts. A previously undescribed nonsynonymous single nucleotide polymorphism, encoding Ala(185)Thr, was identified in exon 4 of the beta-tubulin gene, TUBB, in three other patients. The recommended phase 2 dose in hematologic malignancies is 175 mg/m(2) daily orally for 21 days every 4 weeks. CONCLUSION: Further assessment of ABT-751, especially in combination with other agents, in patients with acute leukemias is warranted.

AC133 Antigen↗

A proof-of-principle pharmacokinetic, pharmacodynamic, and clinical study with purine nucleoside phosphorylase inhibitor immucillin-H (BCX-1777, forodesine).

The discovery of purine nucleoside phosphorylase (PNP) deficiency and T lymphocytopenia suggested that inhibition of this enzyme could serve as a therapeutic target. Inhibitors of PNP failed until structure-based synthesis of immucillin-H (BCX-1777, forodesine), a transition-state analog of PNP. The picomolar potency for PNP, T cell-selective cytotoxicity, and animal studies provided the rationale for use of forodesine in T-cell malignancies. Five patients were treated with an intravenous infusion of forodesine (40 mg/m2) on day 1; treatment continued on day 2; forodesine was administered every 12 hours for an additional 8 doses. Plasma and cellular pharmacokinetics and pharmaco-dynamics were investigated. Median peak level of forodesine (5.4 microM) was achieved at the end of infusion. This level was sufficient to increase plasma 2'-deoxyguanosine (dGuo) concentrations in all patients. Intracellular deoxyguanosine triphosphate (dGTP) increased by 2- to 40-fold in 4 of 5 patients (8 of 9 courses) and correlated with antileukemia activity in 4 patients. However, objective responses were not observed. This was the first clinical study in humans to demonstrate the plasma pharmacokinetics and the pharmacodynamic effectiveness of the PNP inhibitor, forodesine; however, regrowth of leukemia cells in the blood and marrow after course 1 suggested that a different therapeutic schedule should be considered for future studies.

Adult↗

Adult acute megakaryocytic leukemia: an analysis of 37 patients treated at M.D. Anderson Cancer Center.

To characterize acute megakaryocytic leukemia (FAB M7 AML), we identified 37 patients with M7 AML treated at M.D. Anderson Cancer Center between 1987 and 2003 and compared them with 1800 patients with non-M7, non-M3 AML treated during the same period. The median age of the M7 AML group was 56 years (range, 21-78 years); 22 patients (59%) had an antecedent hematologic disorder or myelodysplastic syndrome or both, and 7 patients (19%) had previously received chemotherapy for other malignancies. Extensive bone marrow fibrosis was found in 23 patients (62%). Poor cytogenetic characteristics were observed in 49% of patients with M7 AML versus 33% of others (P < .001). Complete remission rates were 43% with M7 AML and 57% with non-M7 AML (P = .089). Median overall survival (OS) was 23 and 38 weeks, respectively (P = .006). Median disease-free survivals were 23 versus 52 weeks, respectively (P < .001). By multivariate analysis, M7 AML was an independent adverse prognostic factor for OS, independent of other factors including cytogenetic abnormalities (hazard ratio 1.51, P = .049). These results confirm the poor prognosis of M7 AML and indicate that other biologic characteristics beyond cytogenetic abnormalities likely play a role in this disease.

Adult↗

Adaptive randomized study of idarubicin and cytarabine alone or with interleukin-11 as induction therapy in patients aged 50 or above with acute myeloid leukemia or high-risk myelodysplastic syndromes.

A higher complete remission (CR) rate was observed in patients with acute myeloid leukemia (AML) who, on a prior randomized study of induction therapy, received gemtuzumab ozogamicin (GO) plus interleukin-11 (IL-11) rather than GO alone. An adaptive randomized phase III study of the addition of IL-11 to idarubicin and cytarabine (IA) induction in 100 patients >/=50 years of age with AML or high-risk myelodysplastic syndrome (MDS) was conducted. Median patient age was 67 years (range 50-82). Twenty-four of the 45 (53%) patients randomized to IA plus IL-11 achieved CR. Eight (33%) subsequently relapsed, 4 (17%) died in CR; median time to treatment failure (TTF) was 37 weeks. Twenty-nine of the 55 (53%) patients treated without IL-11 achieved CR. Eight (28%) subsequently relapsed, 2 (7%) died in CR; median TTF was 46 weeks. Median overall survivals were 21 and 59 weeks for the IA plus IL-11 and IA cohorts, respectively (p=0.271, log rank test; 0.435, Gehan-Breslow test). Ten episodes of the following grade 3 or 4 cardiopulmonary toxicities were observed in patients receiving IA plus IL-11, 12 such episodes in those receiving IA alone: atrial fibrillation, pleural effusions, myocardial infarction, bradycardia or hypotension. Two patients in each arm experienced grade 3 peripheral edema. There was no significant difference in incidence of any grade 3 or 4 adverse event, including thrombocytopenia, between treatment arms. There was no significant impact on CR rates, TTF, survival, or toxicity of adding an IL-11 regimen to IA induction in patients >/=50 years of age with AML.

Aged↗

Early results of a chemoimmunotherapy regimen of fludarabine, cyclophosphamide, and rituximab as initial therapy for chronic lymphocytic leukemia.

PURPOSE: Fludarabine and cyclophosphamide (FC), which are active in treatment of chronic lymphocytic leukemia (CLL), are synergistic with the monoclonal antibody rituximab in vitro in lymphoma cell lines. A chemoimmunotherapy program consisting of fludarabine, cyclophosphamide, and rituximab (FCR) was developed with the goal of increasing the complete remission (CR) rate in previously untreated CLL patients to >/= 50%. PATIENTS AND METHODS: We conducted a single-arm study of FCR as initial therapy in 224 patients with progressive or advanced CLL. Flow cytometry was used to measure residual disease. Results and safety were compared with a previous regimen using FC. RESULTS: The median age was 58 years; 75 patients (33%) had Rai stage III to IV disease. The CR rate was 70% (95% CI, 63% to 76%), the nodular partial remission rate was 10%, and the partial remission rate was 15%, for an overall response rate of 95% (95% CI, 92% to 98%). Two thirds of patients evaluated with flow cytometry had less than 1% CD5- and CD19-coexpressing cells in bone marrow after therapy. Grade 3 to 4 neutropenia occurred during 52% of courses; major and minor infections were seen in 2.6% and 10% of courses, respectively. One third of the 224 patients had >/= one episode of infection, and 10% had a fever of unknown origin. CONCLUSION: FCR produced a high CR rate in previously untreated CLL. Most patients had no detectable disease on flow cytometry at the end of therapy. Time to treatment failure analysis showed that 69% of patients were projected to be failure free at 4 years (95% CI, 57% to 81%).

Adult↗

Chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab for relapsed and refractory chronic lymphocytic leukemia.

PURPOSE: The efficacy, toxicity, and tolerability of chemoimmunotherapy with the combination of fludarabine, cyclophosphamide, and rituximab (FCR) were evaluated in previously treated patients with chronic lymphocytic leukemia (CLL). The purpose of this study was to improve the complete remission (CR) rate for previously treated patients and evaluate the quality of bone marrow response. PATIENTS AND METHODS: One hundred seventy-seven previously treated patients with CLL were evaluated. Treatment consisted of rituximab 375 mg/m(2) day 1 of course 1 and 500 mg/m(2) day 1 of courses 2 to 6; fludarabine 25 mg/m(2)/d days 2 to 4 of course 1 and days 1 to 3 of courses 2 to 6; and cyclophosphamide 250 mg/m(2)/d days 2 to 4 of course 1 and days 1 to 3 of courses 2 to 6. Courses were repeated every 4 weeks. RESULTS: CR was achieved in 25% of 177 patients, and nodular partial remission and partial remission were achieved in 16% and 32% of patients, respectively; the overall response rate was 73%. Twelve (32%) of 37 complete responders tested achieved molecular remission in bone marrow. Univariate and multivariate analyses were used to identify pretreatment patient characteristics associated with CR and overall remission, longer time to progression, and overall survival. CONCLUSION: The FCR regimen was an active and well-tolerated treatment for previously treated patients with CLL. Myelosuppression was the most common toxicity. FCR induced the highest CR rate reported in a clinical trial of previously treated patients with CLL. Furthermore, molecular remissions were achieved in a third of patients achieving CR.

Adult↗

Phase I study of BMS-214662, a farnesyl transferase inhibitor in patients with acute leukemias and high-risk myelodysplastic syndromes.

PURPOSE: To investigate the dose-limiting toxicity (DLT) and maximum-tolerated dose (MTD) of BMS-214662, a farnesyl transferase (FTase) inhibitor, in patients with acute leukemias and high-risk myelodysplastic syndromes (MDS). PATIENTS AND METHODS: Patients with relapsed or refractory acute leukemias or MDS, or previously untreated but poor candidates for chemotherapy, were included in this phase I study with a 3 + 3 dose escalation design. BMS-214662 was administered as a 1-hour bolus once weekly at doses of 42 to 157 mg/m2. Once the MTD was identified, the schedule was changed to a 24-hour continuous infusion once weekly (starting dose, 300 mg/m2). RESULTS: Thirty patients were treated at a dose of 42 (n = 1), 56 (n = 3), 84 (n = 3), 118 (n = 13), 157 (n = 6) or 300 mg/m2 (n = 4). DLT occurred in 3 patients at 157 mg/m2, including nausea, vomiting, diarrhea, hypokalemia and cardiovascular problems. No DLT occurred with 24-hour continuous infusion. MTD with a 1-hour infusion was 118 mg/m2, with no MTD identified with the 24-hour infusion. Plasma concentrations of BMS-214662 correlated with the dose. Inhibition of FTase activity of approximately 60% occurred after the infusion with recovery to near baseline after 24 hours. Five patients had evidence of antileukemia activity, including two with complete remission with incomplete platelet recovery, one with hematologic improvement, and two with morphologic leukemia-free state. CONCLUSION: BMS-214662 is well tolerated at doses of up to 118 mg/m2 as a 1-hour infusion. The toxicity profile and efficacy may be improved with prolonged exposure. Further investigation of this agent in leukemia is warranted.

Acute Disease↗