ALBERT

Description: DAC is a potent hypomethylating agent with clinical activity in patients with myelodysplastic syndromes (MDS) and acute myelogenous leukemia (AML). VPA is a histone deacetylase inhibitor used as an antiepileptic agent. In vitro, the combination of DAC with VPA results in synergistic antileukemia activity at doses of VPA above 1mM. Based on this data, we have developed a phase I/II study of this combination for pts with leukemia. The phase I of the study followed a classic 3+3 design. The dose of DAC was fixed: 15 mg/m2 iv daily for 10 days. This was based on a previous phase I study (Blood2004;103:1635) that indicated that this schedule had an optimal toxicity-response profile in this population. Three dose levels of VPA were selected: 20, 35 and 50 mg/kg. VPA was given orally for 10 days concomitantly with DAC. 22 pts have completed the phase I portion of the study (median age 56 years, range 4–78, 20 pts AML, 2 MDS). At dose level 1 (20 mg/kg of VPA) no grade III-IV toxicity was observed. At dose level 2 (VPA 35 mg/kg), 2 out 6 pts developed grade III neurotoxicity. Both pts were receiving high doses of other neurotropic agents. After IRB approval, 3 mores pts were treated at this dose level with no significant toxicity. Subsequently, 3 pts were treated at the highest planned dose level (50 mg/kg) with no toxicity observed. This cohort was then expanded to a total of 10 pts. One pt developed grade III neurotoxicity. No other severe drug-related toxicities were observed, but 5 patients at all dose levels developed grade II sedation/somnolence. Pancytopenia was induced in all pts. At dose level 1, one pt with refractory AML achieved complete remission (CR) after the second course of therapy. This is now maintained for 5 courses. At dose level 2, a patient with HIV disease and relapsed AML achieved CR after the third course of therapy, and 2 pts with relapsed AML achieved complete marrow responses (marrow blasts less then 5%, no recovery of peripheral counts). Of 3 pts evaluable for response at dose level 3, 1 pt with MDS has achieved CR after 1 course, and 1 with relapsed AML a complete marrow response. Median free VPA levels pretreatment were 0, and 25 mg/L on both days 5 and 10 and returned to 0 prior to next course. Histone acetylation measured by Western blot was observed in 3 pts (25%), all at doses above 20 mg/kg of VPA. Reactivation of p21 expression was induced in 4 out 11 pts analyzed. Global hypomethylation measured using a bisulfite PCR LINE assay was induced in 1 out 3 pts so far studied. Based on the toxicity observed, the phase II portion of the study was initiated. This is restricted to pts with AML/MDS. Seven pts have been accrued to this phase, and 8 out the 10 pts at dose level 3 of the phase I are also evaluable. The response data of this pts will be updated at the meeting. In summary, the combination of low dose DAC and VPA up to doses of 50 mg/kg can be safely administered to pts with leukemia although it may be complicated by neurotoxicity. Clinical and biological activity was observed at all dose levels.

Description: Hypereosinophilic syndrome (HES) is rare, disabling, and incurable disease. In a pilot study, the combination of 2-CdA and ara-C chemotherapy has been evaluated in 9 patients. The median time from diagnosis to therapy was 25 months. All patients had signs and symptoms of end-organ involvement. Seven patients received prior therapies. The median eosinophil count at presentation was 14 x109/L (0.3–110 x109/L) and the median percent eosinophilic bone marrow infiltration was 23% (6%–43%). Ara-C (1g/m2) was given intravenously over 2 hours at hours 0, 48, 72, 96, and 120; 2-CdA (12 mg/m2/day) was given as continuous infusion intravenously over 5 days starting at 24 hours. A second course at the same level was administered for patients who achieved complete remission (CR) and for patients who had 〉50% reduction in eosinophilic infiltration. Two patients studied for pharmacokinetics of ara-CTP (active metabolite of ara-C) in the circulating blood cells accumulated either similar or higher levels of ara-CTP after infusion of 2-CdA. Five patients (55%) achieved CR, one requiring 2 cycles. Elimination of eosinophilia was accompanied by the resolution of symptoms. The median disease free survival was 26 months; 1 patient remains disease free (after allogeneic transplantation) at 42 months. The median overall survival from diagnosis for CR patients was 44 mo. Treatment was well tolerated. Febrile neutropenia occurred in 28% of the 14 cycles given. The median time to recovery from neutropenia and thrombocytopenia was 17 and 39 days, respectively. There was one death related to disease progression. We conclude that 2-CdA + ara-C combination regimen is safe alternative therapy for HES. The addition of consolidation therapy or imatinib may improve the results.

Description: Background: IFI is the most frequent cause of mortality in pts with AML and MDS undergoing chemotherapy. None of the antifungal prophylactic regimens used since 1992 at MD Anderson Cancer Center appeared to be significantly superior in the prevention of IFI. Study Aims: To compare the efficacy and safety of IV-VORI versus IV-ITRA as antifungal prophylaxis in AML and MDS pts receiving chemotherapy Patients and Methods: Pts older than 18 years old receiving induction or salvage chemotherapy, without documentation of prior IFI were eligible. Pts were randomized on day 1 of chemotherapy to receive IV-VORI 400 mg q12 h x 2 days followed by 300 MG IV twice per day or IV-ITRA 200 mg q12 h x 2 days followed by 200 mg IV once per day. Prophylaxis continue until recovery from neutropenia, developed possible/proven IFI, complete remission, declared resistant or up to 35 days for induction pts and up to 42 days for salvage pts. Results: 114 pts were evaluable (49 on IV-ITRA, 65 on IV-VORI). Baseline characteristics were similar in both groups. 102 were induction pts and 12 were on first salvage. Median time on prophylaxis was 21 (induction) and 17 days (salvage) for both groups. 45% pts on IV-ITRA and 48% pts on IV-VORI completed prophylaxis without modification (p=ns). Two pts on IV-ITRA developed IFI (1 disseminated C. glabrata and 1 disseminated Fusarium) as oppose to none on the IV-VORI arm (p=0.101). No significant differences were seen in the number of pts that required empiric antifungal therapy due to persistent fever or possible fungal pneumonia (14% on IV-VORI, 18% on IV-ITRA). 15/49 pts on IV-VORI (23%) versus 4/49 (8%) on IV-ITRA discontinued prophylaxis due to side effects (p=0.036). Reversible increase in the liver function tests (9 on IV-VORI, 4 on IV-ITRA) and hallucinations (5 on IV-VORI) were the most frequent adverse events. Response to induction chemotherapy, overall induction mortality and survival were similar in both groups. Conclusions: 1) IV-VORI appears to be more efficacious than IV-ITRA in preventing IFI in AML and MDS pts receiving chemotherapy. More pts are needed to confirm this finding. 2) IV-VORI tends to be more toxic than IV-ITRA. The usage of high dose IV-VORI may explain the incidence of side effects.

Description: We explored the safety and efficacy of rituximab plus alemtuzumab in patients with relapsed or refractory lymphoid malignancies. Forty-eight patients were treated and were assessable for response (32 with chronic lymphocytic leukemia [CLL], 9 with CLL/prolymphocytic leukemia [PLL], 1 with PLL, 4 with mantle cell leukemia/lymphoma, 2 with Richter transformation). The overall response rate was 52% (complete remission, 8%; nodular partial response, 4%; partial response, 40%). With a median follow-up of 6.5 months (range, 1-20 months), the median time to progression was 6 months (range, 1-20 months); median survival, 11 months (11+ months for responders vs 6 months for nonresponders). Most toxicities were grade 2 or lower and infusion-related. Infections occurred in 52% of the patients. Cytomegalovirus (CMV) antigenemia assays were positive in 27% of the patients, but only 15% were symptomatic and required therapy. The combination of rituximab and alemtuzumab is feasible, has an acceptable safety profile, and has clinical activity with a short course in a group of patients with poor prognoses.

Description: Human leukocyte antigen-class I (HLA-I) molecules are membrane-associated proteins that contain two separate polypeptide chains: an alpha heavy chain and a beta chain. The beta chain is the b-2 microglobulin (b2-M). Significant levels of free soluble HLA-I (sHLA-I) have been detected in serum and studied as a marker for immunomodulation in patients with infection and after transplant. Little is known about the role of sHLA-I as a tumor marker, despite the documentation of b2-M as a tumor marker. We measured the levels of sHLA-I and b2-M in the plasma of 205 patients with acute myeloid leukemia (AML) and 95 patients with myelodysplastic syndrome (MDS) and assessed the value of both markers in predicting clinical behavior. Both sHLA-I and b2-M were strong predictors of response to therapy (P = 0.03 and P = 0.001, respectively), overall survival (both P

Description: Imatinib has become standard therapy for pts with CML in chronic phase (CP). SBT has been reported in pts receiving IFN-α, at a rate of 0.5% to 2.5% during the first 3 years of therapy. There is little information on the occurrence of SBT among pts treated with imatinib. Here we report 3 pts who developed SBT, defined as occurring after being found in complete cytogenetic remission (CG CR). These 3 pts represent 0.5% of 557 pts who received imatinib at MD Anderson for chronic phase CML. The total population has been followed for a median of 33 months (range, 1 to 56). Pt #1 was a 54 yr old female with a variant Ph translocation, t(9;22;19;10) (q34;q11.2;p13.1;q22). Sokal risk was low. She started imatinib 400mg/day within 4 mos from diagnosis, achieved a CG CR within 3 mos and was still in CG CR after 9 mos with BCR-ABL/ABL 0.66%. On routine follow-up at 12 mos she was found in myeloid blast phase with 48,XX,+8,t(8;21)(q22;q22),t(9;22;19;10) (q34;q11.2;p13.1;q22), +der(22)t(9;22;19;10) in all 20 metaphases. She received standard induction chemotherapy followed by bone marrow transplantation and is alive and in CR after 24+ months. Pt #2 was a 51 yr old female initially treated with IFN-α. She achieved a CG CR but discontinued therapy because of toxicity after 18 mos. Fourteen mos after stopping IFN-α she had a CG recurrence (35% Ph-positive) and was started on imatinib 400mg/day. Three mos later she was in CG CR and BCR-ABL was undetectable by nested PCR; a similar result was found after 9 mos of therapy. 9 mos later (18 mos after start of imatinib) she had a lymphoid SBT (precursor B-cell). CG showed 45,XX,-8, t(9;22) (q34;q11.2), −20,+mar in one metaphase, and 11 metaphases were diploid. No ABL mutations were identified. She achieved CR with HCVAD + imatinib and is currently receiving a BMT. Patient #3 was a 27 yr old pt who received imatinib 800 mg/d as first line of therapy for CML in CP with intermediate Sokal risk score. Three mos after start of therapy he was in CG CR and repeated analyses showed continued CG CR up to mo 15, with the lowest BCR-ABL/ABL 0.12 at mo 6. On mo 18 he had a lymphoid SBT (precursor B phenotype) with 43–46,XY, −7, −8,i(9)(q10),t(9;22)(q34;q11.2), −13, −17, −21,+der(22)t(9;22),+mar in 13 metaphases and one diploid metaphase. No ABL mutations were identified. He was treated with HCVAD + imatinib and achieve a CR, becoming undetectable for BCR-ABL by nested PCR. He is undergoing a BMT. In pts 2 and 3, transformation was associated with a sudden drop in platelet counts. These isolated events should alert the physicians to continued monitoring of pts on imatinib and consider marrow studies in the event of late, unexpected peripheral blood count changes. Still, SBT is rare, probably less common that seen with IFN-α therapy.

Description: Imatinib mesylate is effective against Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL) but, when used as a single agent, responses are transient and most patients relapse within 4–6 months. AMN107 is a novel oral aminopyrimidine ATP-competitive inhibitor of the protein tyrosine kinase activity of Bcr-Abl. Following oral administration to animals, AMN107 is well absorbed, has a good pharmacokinetic profile, and is well tolerated. The activity of AMN107, relative to imatinib, in both Ph-positive (Z-119 and Z-181) and Ph-negative (Z-138) ALL cell lines was studied. Z-119 and Z-181 cells were derived from Ph-positive ALL patients and retained typical B-cell characteristics and phenotypes of the original leukemia, including cytogenetic abnormality t(9;22) and p190 Bcr/Abl kinase. Z-138, a Ph-negative cell line, was derived from a patient with chronic lymphocytic leukemia and supervening ALL. Treatment with AMN107 or imatinib for 3 days (MTS assay) inhibited proliferation of Z-119 cells with the IC50 values of 19.3 nM and 620.0 nM, respectively, revealing AMN107 to be 32 fold more potent than imatinib. Treatment of Z-181 cell line lasted for 4 days (MTS assay) because of lower growth rate of these cells: IC50 for AMN107 and imatinib were 1.6 nM and 63.9 nM, respectively, showing AMN107 to be 40 fold more potent than imatinib. Neither drug showed activity against Ph-negative Z-138 cells. We also compared the activity of AMN107 in Ph-positive ALL cell lines expressing p190 Bcr/Abl protein to that in Ph-positive chronic myeloid leukemia cell lines KBM5 and KBM7 expressing p210 Bcr/Abl protein. The activity was similar with IC50 in KBM5 cells of 11.3 nM and in KBM7 cells of 4.3 nM. In experiments focused on cell cycle analysis we found that at equipotent doses (as determined by MTS assay) both drugs induced cell accumulation in G0/G1 phase in Z-119 but not in Z-181. We demonstrated that increasing equipotent concentrations of AMN107 and imatinib induced activation of caspase-3 that resulted in apoptosis, as assessed by propidium iodide staining, in Z-119 cells, while Z-181 cells showed lack of apoptotic response. Following treatment with a broad range of AMN107 and imatinib doses for 3 hrs, Bcr/Abl expression and phosphorylation were determined in Z-119 cells by immunoprecipitation and Western blotting: Bcr/Abl phosphorylation was inhibited completely with AMN107 at 125.0 nM, and with imatinib at 2500 nM, confirming again the higher potency of AMN107. Finally, similar differential effect of AMN107 and imatinib on Bcr/Abl protein expression and phosphorylation was observed in leukemic cells obtained from blood of Ph-positive ALL patients. We conclude that AMN107 has significant activity against Ph-positive ALL cells and warrants investigation in patients with Ph-positive ALL.

Description: Therapeutic responses to interferon-a (IFN-a) therapy in patients with malignancies are at least in part from the effects of IFN-a on the enhancement of anti-tumor immune responses. Antigens responsible for immune responses enhanced by IFN-a remain largely unknown. Polycythemia vera (PV) is a myeloproliferative disease (MPD) resulting from the clonal expansion of a pluripotential hematopoietic precursor cell. IFN-a therapy induces a complete remission in ~50% of PV patients, thus making PV a good model to study the molecular mechanism of the cytokine-enhanced immune responses against tumors. We hypothesized that IFN-a enhances anti-PV immune responses by modulating the expression of non-mutated self-antigens. We identified three novel MPD antigens by applying a technique, termed serological identification of tumor antigens by expression cDNA cloning (SEREX), to screen a human testis cDNA library with sera from three PV patients who responded to IFN-a therapy. Of these three novel SEREX antigens, MPD5 belongs to the newly identified group of unconventional cryptic antigens. These unconventional antigens are encoded by either the introns of genes, or the untranslated regions of mRNAs. MPD5 is the antigen encoded by the complementary strand of the intron 1 region of NEK-6 gene. Two additional MPD antigens, MPD13 and MPD67, are conventional antigens, which are encoded by the genes with conventional exon/intron structures. Our results showed that these novel MPD antigens elicit potent IgG antibody immune responses in the sera of patients with PV, as well as patients with chronic myelogenous leukemia who responded to IFN-a treatment and in patients with prostate cancer, suggesting that these antigens are broadly immunogenic. Previous reports showed that unconventional antigens can elicit cellular T cell mediated responses. Our data demonstrated that these antigens also elicit humoral IgG antibody responses, which can be further enhanced by IFN-a therapy. These findings provide new insights into the molecular mechanism underlying the regulation of the self-antigen repertoire including both conventional antigens and unconventional antigens, in eliciting anti-tumor immune responses in responses to IFN-a therapy, and suggest their therapeutic potential as the targets of novel immunotherapy for MPD.

Description: The criteria to define chronic (CP), accelerated (AP) and blast phase (BP) CML vary in the literature. The WHO recently proposed, based on the literature and collective experience of the clinical advisory committee, new criteria for myeloid malignancies including CML in an attempt to provide more uniform criteria (Blood2002; 100:2292). Imatinib is the current standard therapy for CML, and the criteria used in most studies using imatinib are shown below in contrast to the WHO proposal: Phase Criteria Imatinib WHO *Unrelated to therapy (Rx), **Unresponsive to Rx, Plts=platelets, BM=bone marrow AP Blasts 15–29% 10–19% Blasts + promyelocytes ≥ 30% NA Basophils ≥ 20% ≥ 20% Plts 1000 x 109/L** No Yes Increasing spleen size and WBC** No Yes CE At any time Not at diagnosis (Dx) BP Blasts ≥ 30% ≥ 20% Extramedullary disease Yes Yes Large clusters of blasts in BM NA Yes We investigated the clinical validity of the WHO proposal among 809 patients (pts) with CML in all stages treated with imatinib at MDACC since 1999. According to the imatinib classification, 537 (66%) pts were in CP, 196 (24%) in AP, and 76 (9%) in BP. When analyzing the specific subsets of pts where the classifications differ, major findings are: 1) Pts with CE at Dx (n=14) have similar cytogenetic (CG) complete remission (CR) rate (86%) than pts (n=477) with imatinib CP (75%, p=.53), but it is lower when CE develops after Dx (34/64, 53%; p=.0005). Similar results are found for overall survival (OS) and progression-free survival (PFS). 2) CG CR rate among pts with 20%–29% blasts (4/19, 21%) is more similar to that of AP (37/99, 37%)(p=0.19) than to pts with ≥30% blasts (5/76, p=0.07). This trend is more significant for OS and PFS. 3) Pts with increasing WBC and spleen, or plts 〉1000 x109/L unresponsive to Rx have a CG CR rate (9/42, 21%; p=.07) lower than others with AP, but there is no difference in OS or PFS. 4) Pts with plts 〉1000 x109/L without prior Rx have similar outcome as those with CE developing on therapy. In conclusion, based on results imatinib therapy, AP can be defined as blasts ≥10%, basophils ≥20%, plt 1000 x109/L (unresponsive to Rx), increasing WBC and spleen (unresponsive to Rx), and CE not at diagnosis; BP is defined by blasts ≥30% or extramedullary disease; pts who develop CE during the course of Rx of with plts 〉1000 x109/L not related to Rx constitute an intermediate group between CP and AP; all others are CP.

Description: The value of prolonged administration of arsenic trioxide (ATO) was examined in patients (pts) with MDS and CMML. ATO (0.25 mg/kg) was given intravenously over 1 hour daily for five days followed by 0.25 mg/kg twice weekly for 11 weeks. Pts were assessed at 4 weeks, at the end of the first course, and then monthly. Pts with stable disease were eligible for further courses. The study included 14 RBC transfusion-dependent MDS pts (6 RA/RARS, 8 RAEB; 12 IPSS risk Low/Int1, 2 Int2/High), and 3 CMML pts. Median age was 67 years (range 46–84). Six pts had a history of previous treatment other than supportive care. 16 pts were evaluable for toxicity and response. One pt received 3 courses, 3 received 2 courses, and 13 received 1 course. Hematologic responses (IWG criteria) were observed in 4 pts (25%) and 9 (6 MDS,3 CMML) had stable disease: FAB Type of response Time to response Duration RA Minor erythroid 2 months 3 mo, RBC independence RAEB Major neutrophil and platelet 2 mo 3 mo RAEB BM blast decrease 18% to