Clinical Trial of Paricalcitol in Myelodysplastic Syndrome.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4720-4720
Author(s):  
H. Phillip Koeffler ◽  
James O’Kelly ◽  
Noune Aslanian ◽  
Keyword(s):  
Clinical Trial ◽  
Myelodysplastic Syndrome ◽  
Clinical Response ◽  
Vitamin D3 ◽  
Single Agent ◽  
White Blood Cells ◽  
The Elderly ◽  
Leukemic Cells

Abstract Myelodysplastic syndrome is often a pernicious disorder associated with pancytopenia in the elderly. Therapeutic approaches need to balance their toxicities versus the side-effects of the disease. 1,25(OH)2-vitamin-D3 inhibits proliferation and induces differentiation of leukemic cells in vitro. Small clinical trials have shown slight efficacy in MDS. Hypercalcemia prevents the administration of doses of this seco-steroid, which have been shown to be effective in vitro. This has provided a stimulus to identify vitamin D analogs that have anti-leukemic activity with minimal hypercalcemic effects. Paricalcitol (19-nor-1,25(OH)2D2, Zemplar) has been approved by the FDA for the treatment of secondary hyperparathyroidism; the drug is unique because it has little hypercalcemic potential; but in vitro, it has strong antileukemic effects. We conducted a clinical trial of oral paricalcitol to twelve MDS patients whose disease varied between an IPSS of low to high. Therapy began at 8 μg per day and increased at two week intervals until serum calcium was slightly above normal level; at which point, dose was decreased by 4-8 μg qd. The amount of paricalcitol taken varied between 8 μg qod to 54 μg qd (average 16 μg qd). We confirmed that the drug was having biologic activity in vivo by examining a target of the activated vitamin D3 receptor, 1,25-(OH)2-vitamin-D3-24(OH)ase mRNA. Each patient had prominent induction of this transcript in his or her white blood cells. Furthermore, in selected patients serum paricalcitol was measured and confirmed to be prominently present. The drug was well tolerated in all patients. Two of the 12 patients showed a clinical response. One patient’s platelet counts rose from 50,000 to 120,000/ul blood over 5 weeks; however, the patient succumbed to a fatal fungal infection. The second patient responded by a decrease in RBC transfusions associated with a rise in his hemoglobin, which lasted for about 5 months. Eventually, his hemoglobin began to fall, and erythropoietin therapy was substituted for paricalcitol. In summary, high doses of paricalcitol were well tolerated in all patients. Two patients had a partial clinical response. In general, paricalcitol given as a single agent to individuals with MDS is not therapeutically very efficacious; further trials should examine it in combination with other approaches.

Pharmacokinetic and Pharmacodynamic Effects of PEG-Asparaginase in Newly Diagnosed Childhood Acute Lymphoblastic Leukemia: Results from a Single Agent Window Study.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 860-860
Author(s):  
Inge M. Appel ◽  
Karin M. Kazemier ◽  
Anjo J.P. Veerman ◽  
Elisabeth van Wering ◽  
Monique L. Den Boer ◽  
...  
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Clinical Response ◽  
Lymphoblastic Leukemia ◽  
Single Agent ◽  
Hazard Ratio ◽  
Leukemic Cells ◽  
Newly Diagnosed ◽  
Pharmacodynamic Effects

Abstract L-Asparaginase is an effective drug for treatment of children with acute lymphoblastic leukemia. The effectiveness is generally thought to result from a rapid depletion of asparagine in serum and cells. Several studies have shown that in vitro resistance to this drug is an independent prognostic factor in ALL. We investigated the clinical response of one in vivo dose of 1000 IU/m2 PEG-Asparaginase and its pharmacokinetic and pharmacodynamic effects in children with newly diagnosed ALL before the start of combination chemotherapy. 57 children (36M / 21F) were enrolled in the study: 2 pro B-ALL, 38 common/ pre B-ALL and 17 T-ALL. Genotyping of precursor B-ALL revealed 11 hyperdiploid, 8 TELAML1 positive, 2 BCRABL positive, no MLL rearrangement, 8 normal, 11 others. The clinical response to PEG-Asparaginase on day 0 (5 days after the PEG-Asparaginase infusion) was defined as good when the number of leukemic cells of peripheral blood was < 1 × 109/L, as intermediate when leukemic cells were 1-10 × 109/L, and as poor when leukemic cells were > 10 × 109/L. The in vivo window response was significantly related to immunophenotype and genotype: 26/38 common / pre B-ALL cases, especially those with hyperdiploidy and TELAML1 rearrangement, demonstrated a good clinical response compared to 8/17 T-ALL (p=0.01). Both BCRABL positive ALL cases showed a poor response (p=0.04). A poor in vivo clinical window response was related to in vitro resistance to L-Asparaginase (p=0.02) and both in vitro as well as in vivo response were prognostic factors for long-term event-free survival (Hazard ratio 6.4; p=0.004, and Hazard ratio 3.7; p=0.01, respectively). The L-Asparaginase activity in the serum was >100 IU/L for at least 15 days. The asparagine levels remained below the detection limit of 0.2 mM for at least 26 days with a concomitant rise in serum aspartate and glutamate. These findings confirm that PEG-Asparaginase will yield its pharmacodynamic effects for 2-4 weeks. After administration of one in vivo dose of 1000 IU/m2 PEG-Asparaginase no changes in apoptotic parameters or changes in intracellular levels of twenty amino acids in leukemic cells could be measured, in contradiction to the changes found after in vitro exposure. This may be explained by the rapid removal of apoptotic cells from the circulation in vivo. Otherwise it is possible that in vivo mesenchymal cells from the bone marrow supply leukemic blasts with asparagine in response to treatment with L-Asparaginase. Conclusion: The clinical response to one dose of 1000 IU/m2 PEG-Asparaginase intravenously is related to phenotype and genotype and predicts outcome. These results suggest that children with ALL with a poor clinical response to PEG-Asparaginase might benefit from a more intensive antileukemic therapy.

Development of a novel 1,25(OH)2-vitamin D3 analog with potent ability to induce HL-60 cell differentiation without modulating calcium metabolism

Blood ◽  
1991 ◽  
Vol 78 (1) ◽  
pp. 75-82 ◽  
Author(s):  
JY Zhou ◽  
AW Norman ◽  
M Akashi ◽  
DL Chen ◽  
MR Uskokovic ◽  
...  
Keyword(s):  
Vitamin D3 ◽  
Calcium Metabolism ◽  
Calcium Absorption ◽  
Leukemic Cells ◽  
Inhibition Of Proliferation ◽  
Myc Oncogene ◽  
Differentiation And Proliferation ◽  
Bone Abnormalities

We describe several novel analogs of the seco-steroid 1,25(OH)2-vitamin D3[1,25(OH)2D3] and their effects on differentiation and proliferation of HL-60 human myeloid leukemic cells in vitro as well as their effects on calcium metabolism in vivo. The 1 alpha-25(OH)2–16ene-23yne-26,27F6- vitamin D3 is the most potent analog reported to date, having about 80- fold more activity than the reference 1,25(OH)2D3 for inhibition of proliferation and induction of differentiation of HL-60 cells. Also, this analog decreased RNA expression of MYC oncogene in HL-60 by 90% at 5 x 10(-10) mol/L. Intriguingly, intestinal calcium absorption and bone calcium mobilization mediated in vivo by 1 alpha-25(OH)2–16ene-23yne- 26,27F6-D3 was found to be markedly (15-fold) less than that of 1,25(OH)2D3. In addition, 1 alpha-25(OH)2D3 bound to 1,25(OH)2D3 receptors of both HL-60 and intestine more avidly than did 1 alpha- 25(OH)2–16ene-23yne-26,27F6-D3. This novel analog may open up new therapeutic strategies for several hematopoietic, skin, and bone abnormalities and may provide a new tool to understand how vitamin D3 seco-steroids induce cellular differentiation.

Antimyeloma Efficacy of Plitidepsin (Aplidin®): From Bench to the Bedside.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1178-1178 ◽  
Author(s):  
Enrique M. Ocio ◽  
Constantine Mitsiades ◽  
M. Victoria Mateos ◽  
Patricia Maiso ◽  
Faustino Mollinedo ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Cell Lines ◽  
Single Agent ◽  
In Vitro Studies ◽  
Parp Cleavage ◽  
Hematologic Toxicity ◽  
Cell Transplant ◽  
Significant Toxicity

Abstract Introduction Plitidepsin is a cyclic depsipeptide isolated from the marine tunicate, Aplidium albicans with promising antitumor activity. This work represents a comprehensive study (in vitro, in vivo and clinical) of its antimyeloma efficacy. Material & Methods In vitro studies were performed in 23 multiple myeloma (MM) cell lines and in cells from 16 MM patients. For the in vivo analysis a human plasmocytoma model in CB17-SCID mouse was used. Mice were randomized to receive Aplidin® 100 μg/Kg ip x 7 days/week (n=9), Aplidin® 140 μg/Kg ip x 5 days/week (n=7) or vehicle alone (n=9). The clinical efficacy of Aplidin® in relapsed/refractory patients was evaluated in a non-randomized two-stage Phase II, multicenter, clinical trial. Dosage of Aplidin® was 5 mg/m2 every 2 weeks. Results Aplidin® showed clear in vitro efficacy (IC50:1–10 nM) in the 23 cell lines tested including those resistant to dexamethasone, melphalan or doxorubicin. It was also active in the presence of microenvironment (IL-6, IGF-1 and BMSCs). Thirteen out of the 16 patient samples were sensitive to Aplidin® with >80% cell death in 8 cases and 60–80% in the remaining ones without significant toxicity in non tumor cells. Combination of Aplidin® with dexamethasone, bortezomib or lenalidomide showed clear potentiation. Aplidin® acts by inducing apoptosis with caspase−3, −7, −8, −9 and PARP cleavage. It also involves the activation of p38 and JNK signalling, Fas/CD95 translocation to lipid rafts and downregulation of Mcl-1 and myc. In mice studies, both schedules of treatment reduced tumor growth and increased survival with statistical differences in the group receiving 140 μg/Kg x 5d/week (p=0.04, Log Rank p=0.02). No significant toxicity was observed. These data provided the rationale for a clinical trial that has included 31 patients with relapsed/refractory MM. Median age was 65 years (47–82) and the median number of prior lines of therapy was 4 (range: 1–9) including autologous stem cell transplant (60%), thalidomide (58%) and bortezomib (48%). Out of the 26 evaluable patients, 2 (8%) achieved PR and 3 (12%) MR. Eight patients (31%) remained in stable disease (SD). Due to the synergism with dexamethasone observed in the in vitro studies, the protocol was amended to allow the addition of this agent in pts progressing after 3 cycles or with SD after 4 cycles. With a median follow-up of 14 months (range: 6.8–16.3), the time to progression in responding pts was 5.8 months (4.9–7.6). The most common G3-4 adverse events were fatigue (7%), serum creatine phosphokinase increase (7%), muscle toxicity (10%) and hepatic toxicity (10%). No significant hematologic toxicity or neuropathy was observed. Conclusion Aplidin® is effective both as a single agent and in combination with dexamethasone in the in vitro and in vivo settings. Its activity in relapsed/refractory MM patients is promising with an acceptable toxicity profile.

Pronounced Anti-Leukemia Activity in Vivo of the Novel Peptidic CXCR4 Antagonist LY2510924 As a Single Agent and in Combination with Chemotherapy

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3745-3745
Author(s):  
Byung-Sik Cho ◽  
Zhihong Zeng ◽  
Hong Mu ◽  
Zhiqiang Wang ◽  
Teresa McQueen ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
Cultured Cells ◽  
Single Agent ◽  
Leukemic Cells ◽  
Cxcr4 Antagonist ◽  
Nsg Mice ◽  
Xenograft Models

Abstract LY2510924 is a novel selective peptidic CXCR4 antagonist that blocks SDF-1α from binding to its receptor. We have demonstrated that LY2510924 at nanomolar concentrations durably disrupts the SDF-1α/CXCR4 axis in acute myeloid leukemia (AML) cells and exerts anti-leukemia effects as a single agent (AACR 2014: #4768). We further investigated the pronounced anti-leukemia activity of LY2510924 and the mechanisms underlying the anti-leukemia effect. To test the efficacy of LY2510924 in combination with chemotherapy, we injected OCI-AML3/luc/GFP cells into NSG mice. Mice were randomized into 4 groups (10 mice per group) on day 8: control, chemotherapy (cytarabine [50 mg/kg, daily for 5 days, intravenous or intraperitoneal]/doxorubicin [1.5 mg/kg, daily for 3 days, co-delivered intravenously]), LY2510924 (2.5 mg/kg, daily for 3 weeks, subcutaneously), or chemotherapy and LY2510924. Bioluminescence imaging demonstrated that LY2510924 exerted an anti-leukemia effect equal to that achieved with chemotherapy (P=0.249), and the combination therapy group had the lowest luciferase activity. LY2510924-treated mice had prolonged survival (Figure 1) compared to controls (52 days vs. 40 days, p=0.006), and combination therapy extended survival even further (62 days vs. 52 days, p=0.004). Next, we examined anti-leukemia efficacy of LY2510924 in primary human AML xenograft models. NSG mice were injected with primary AML cells and randomized into 2 groups on day 25, after engraftment was documented: control (n=13) and treatment with LY2510924 (n=15; 2.5 mg/kg subcutaneously, daily). First, we examined AML cell mobilization by measuring the proportion of circulating leukemic cells after daily LY2510924 administration. Mice treated with LY2519024 had a significant increase of circulating leukemic cells at 3 hours (2.1-fold, P=0.008), and further increases at 24 hours (2.7-fold, P=0.008) and 48 hours (3.0-fold, P=0.009) compared to controls. Flow cytometry showed a sustained inhibition of CXCR4 12G5 surface expression at 3 and 24 hours after the first LY2510924 injection. Thereafter, weekly examination of circulating leukemic cells in both groups revealed slower progression of leukemia in the LY2510924-treated group (54% vs. 86% circulating AML cells on day 45, P<0.001). Additionally, we sacrificed 3 mice per group on days 35 and 45 and demonstrated that LY2510924-treated mice had significantly lower leukemic cell burden in the spleen (22% vs. 51%, P=0.001) on day 35, and in both spleen (20% vs. 60%, P<0.001) and bone marrow (72% vs. 90%, P=0.012) on day 45 by flow cytometry. CXCR4 blockade with LY2510924 was associated with reduced AKT and/or ERK signaling in leukemic cells of spleen, bone marrow, and blood as measured by multi-parametric phospho-flow cytometry. This anti-leukemia effect translated into a significant prolongation of survival in LY2510924-treated mice (56 days vs. 44 days, p<0.001, Figure 2). Our previous study (AACR 2014:#4768) demonstrated that LY2510924 did not induce AML cell death in vitro on its own but inhibited AML cell growth in co-cultures with human marrow stromal cells (hMSC). To explore how CXCR4-mediated signaling in AML cells elicits anti-leukemia effects, we performed whole gene expression profiling of FACS-sorted OCI-AML3 cells co-cultured with hMSC for 48 hours and co-treated with LY2510924, in duplicates. Among genes modified by CXCR4 antagonist, we found that CTNNB1 (human beta-catenin), JARID1C (lysine-specific demethylase 5C), RARA (retinoic acid receptor alpha), RARRES2 (chemerin), and COQ4 (coenzyme Q) were downregulated in co-cultured OCI-AML3 cells treated with LY2510925, when compared to either mono-cultured cells or co-cultured cells without LY2510924. These findings are currently being validated by using functional in vitro assays. In conclusion, our findings demonstrate that CXCR4 antagonist LY2510924 inhibits AML progression in leukemia xenograft models in vivo and has a synergistic anti-leukemia effect in combination with chemotherapy. LY2510924 efficiently inhibits CXCR4 signaling in primary AML cells in vivo and induces mobilization of leukemic cells into circulation. This results in pronounced anti-leukemia activity as a single agent. LY2510924's potency and durable occupancy of CXCR4 receptors will likely translate into greater anti-leukemia potency in future clinical applications. Disclosures Peng: Eli Lilly & Company: Employment. Thornton:Eli Lilly & Company: Employment, stocks Other.

scholarly journals Expression of Apoptosis-Regulating Proteins in Chronic Lymphocytic Leukemia: Correlations With In Vitro and In Vivo Chemoresponses

Blood ◽  
1998 ◽  
Vol 91 (9) ◽  
pp. 3379-3389 ◽  
Author(s):  
Shinichi Kitada ◽  
Janet Andersen ◽  
Sophie Akar ◽  
Juan M. Zapata ◽  
Shinichi Takayama ◽  
...  
Keyword(s):  
Cell Death ◽  
Chronic Lymphocytic Leukemia ◽  
Caspase 3 ◽  
Single Agent ◽  
White Blood Cells ◽  
Lymphocytic Leukemia ◽  
In Vitro Chemosensitivity ◽  
Apoptotic Protein

Abstract B-cell chronic lymphocytic leukemia (B-CLL) represents a neoplastic disorder caused primarily by defective programmed cell death (PCD), as opposed to increased cell proliferation. Defects in the PCD pathway also contribute to chemoresistance. The expression of several apoptosis-regulating proteins, including the Bcl-2 family proteins Bcl-2, Bcl-XL, Mcl-1, Bax, Bak, and BAD; the Bcl-2–binding protein BAG-1; and the cell death protease Caspase-3 (CPP32), was evaluated by immunoblotting using 58 peripheral blood B-CLL specimens from previously untreated patients. Expression of Bcl-2, Mcl-1, BAG-1, Bax, Bak, and Caspase-3 was commonly found in circulating B-CLL cells, whereas the Bcl-XL and BAD proteins were not present. Higher levels of the anti-apoptotic protein Mcl-1 were strongly correlated with failure to achieve complete remission (CR) after single-agent therapy (fludarabine or chlorambucil) (P = .001), but the presence of only seven CRs among the 42 patients for whom follow-up data were available necessitates cautious interpretation of these observations. Higher levels of the anti-apoptotic protein BAG-1 were also marginally associated with failure to achieve CR (P = .04). Apoptosis-regulating proteins were not associated with patient age, sex, Rai stage, platelet count, hemoglobin (Hb) concentration, or lymph node involvement, although higher levels of Bcl-2 and a high Bcl-2:Bax ratio were correlated with high numbers (>105/μL) of white blood cells (WBC) (P = .01; .007) and higher levels of Bak were weakly associated with loss of allelic heterozygosity at 13q14 (P = .04). On the basis of measurements of apoptosis induction by fludarabine using cultured B-CLL specimens, in vitro chemosensitivity data failed to correlate with in vivo clinical response rates (n = 42) and expression of the various apoptosis-regulating proteins. Although larger prospective studies are required before firm conclusions can be reached, these studies show the expression in B-CLLs of multiple apoptosis-regulating proteins and suggest that the relative levels of some of these, such as Mcl-1, may provide information about in vivo responses to chemotherapy. In vitro chemosensitivity data, however, do not appear to be particularly useful in predicting responses in B-CLL.

scholarly journals Efficacy of Focal Adhesion Kinase Inhibition in Combination with Dasatinib in BCR-ABL1 Acute Lymphoblastic Leukemia

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 3766-3766 ◽  
Author(s):  
Michelle L. Churchman ◽  
Luke Jones ◽  
Kathryn Evans ◽  
Jennifer Richmond ◽  
Irina M Shapiro ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Lymphoblastic Leukemia ◽  
Lymphoblastic Leukemia ◽  
Single Agent ◽  
Leukemic Cells ◽  
Employment Equity ◽  
Self Renewal ◽  
Equity Ownership

Abstract Introduction: BCR-ABL1+ B-progenitor acute lymphoblastic leukemia (Ph+ B-ALL) is a highly aggressive disease that is often refractory to currently available therapies. Our previous genomic profiling studies have identified loss-of-function or dominant negative mutations in IKZF1, encoding the lymphoid transcription factor Ikaros, in over 80% of Ph+ ALL. In addition, deletion of CDKN2A, which encodes the INK4A and ARF tumor suppressors, is observed in approximately half of all cases (Mullighan et al., 2008). Alterations of IKZF1 are associated with poor outcome despite the use of tyrosine kinase inhibitors (TKIs). Ikzf1 alterations, including Ikaros isoform 6 (IK6), result in the acquisition of stem cell-like features, enhanced self-renewal, expression of adhesion molecules, and transcriptional upregulation of focal adhesion kinase (FAK), resulting in increased adhesion in vitro and in vivo, and decreased sensitivity to TKIs (Churchman, Cancer Cell, in press). VS-4718 is a potent, selective, and orally bioavailable FAK inhibitor currently under evaluation in a phase 1 clinical trial in subjects with various solid tumors, however in vivo efficacy in hematological malignancies had not been evaluated. Targeting FAK with VS-4718 is an attractive approach to abrogate the adhesive phenotype of IKZF1-altered leukemic cells potentially enhancing the effects of dasatinib in the treatment of high-risk BCR-ABL1 B-ALL. Methods: We examined the efficacy and mechanisms of FAK inhibition using VS-4718 as a single agent and in combination with dasatinib in vitro and in vivo in a range of xenograft and genetically engineered mouse models of BCR-ABL1 ALL. Each model had concomitant deletion of Arf which is observed in approximately 50% of human cases. Results: A pre-clinical in vivo trial of dasatinib and VS-4718 combination therapy in a murine C57Bl/6 Arf-/- BCR-ABL1 pre-B cell model resulted in a marked increase in survival in both IK6-expressing and non-IK6 cohorts of mice, and one complete long-term remission in the IK6-expressing group. Further, we showed increased efficacy of VS-4718 and dasatinib, compared to either agent alone, against two highly aggressive human Ph+ IK6-expressing B-ALL xenografts in vivo, with decreased infiltration of leukemic cells in bone marrow and spleens demonstrating a synergistic effect of the VS-4718/dasatinib combination. In vitro cell viability was reduced with induction of apoptosis at increasing concentrations of VS-4718 as a single agent, and further potentiated the effects of dasatinib in cytotoxicity assays using human xenografted and murine leukemic cells. VS-4718 profoundly diminished the ability of BCR-ABL1-expressing cells to form cell-matrix adhesions in vitro, as evident by the reduced adherence to fibronectin monolayers and bone marrow stromal cells. VS-4718 almost completely abolished the colony-forming potential of BCR-ABL1-expressing murine pre-B cells with and without Ikzf1 alterations at drug concentrations that do not affect cell viability suggestive of a reduction in self-renewal. Calvarial imaging of mice transplanted with Ikzf1-altered BCR-ABL1 leukemic cells and treated with VS-4718 alone in vivo revealed a discernible reduction in adhesion in the intact bone marrow niche of Prrx1-Cre; LSL-tdTomato recipient mice. VS-4718 treated leukemic cells localized to Prrx1-expressing perivascular endothelial cells and exhibited round morphology in contrast to the typical spindle-like appearance of Ikzf1-altered pre-B cells adhering to the bone marrow stroma, suggesting that VS-4718 treatment abolished the aberrant leukemic cell-stromal adhesion induced by Ikaros alterations in vivo. Conclusions: Direct inhibition of FAK with VS-4718 attenuates the adhesive, stem-like properties of IKZF1-altered BCR-ABL1 leukemic cells that contribute to the poor prognosis of patients treated with currently available therapies. Targeted FAK inhibition is thus a promising avenue for improving the response of BCR-ABL1 ALL to dasatinib, particularly in refractory cases harboring IKZF1 alterations. These data support the clinical development of VS-4718 in combination with dasatinib in Ph+ B-ALL. Disclosures Shapiro: Verastem: Employment, Equity Ownership. Pachter:Verastem: Employment, Equity Ownership. Weaver:Verastem: Employment, Equity Ownership. Mullighan:Amgen: Honoraria, Speakers Bureau; Cancer Science Institute: Membership on an entity's Board of Directors or advisory committees; Loxo Oncology: Research Funding; Incyte: Consultancy, Honoraria. Off Label Use: The FAK inhibitor VS-4718 for the treatment of BCR-ABL1 acute lymphoblastic leukemia in preclinical models.

Phase I Study of IMGN901, Used as Monotherapy, in Patients with Heavily Pre-Treated CD56-Positive Multiple Myeloma - A Preliminary Safety and Efficacy Analysis.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2883-2883 ◽  
Author(s):  
Asher Chanan-Khan ◽  
Jeffrey Wolf ◽  
Mecide Gharibo ◽  
Sundar Jagannath ◽  
Nikhil C. Munshi ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Multiple Myeloma ◽  
Board Of Directors ◽  
Dose Level ◽  
Single Agent ◽  
Duration Of Treatment ◽  
Advisory Committees ◽  
Grade 3

Abstract Abstract 2883 Poster Board II-859 Background: IMGN901 (huN901-DM1/BB-10901) is a novel anticancer agent consisting of a potent cytotoxic maytansinoid, DM1, attached to a CD56-binding monoclonal antibody, huN901, using an engineered linker. Once bound to CD56 on a cancer cell, the conjugate is internalized and releases DM1. About 70% of multiple myeloma (MM) cases have surface expression of CD56. In preclinical settings, IMGN901 showed significant in vitro and in vivo anti-myeloma activity as a single agent and in combination with approved drugs such as lenalidomide. Objectives: To determine the maximum tolerated dose (MTD), pharmacokinetics (PK), and activity of IMGN901, used as monotherapy, in patients with MM. Methods: Patients with CD56+ relapsed or relapsed/refractory MM receive a single IV infusion of IMGN901 on 2 consecutive weeks every 3 weeks. Patients are enrolled into each dose level in cohorts of 3, with dose-limiting toxicity (DLT) triggering cohort expansion. The European Bone Marrow Transplant (EBMT) criteria were used for response assessment. Results: Twenty-three CD56+ MM patients have received IMGN901 at doses ranging from 40 to 140 mg/m2/week. Most of these 23 patients had been treated with 6 or more chemotherapy regimens prior to study entry. Two of 6 patients treated at the 140 mg/m2/week dose experienced DLT (grade 3 fatigue and grade 3 acute renal failure) and a lower dose has been defined as the MTD. Commonly reported adverse events that were at least possibly related to IMGN901 were fatigue, increased aspartate aminotransferase, increased uric acid, sensory neuropathy and headache. None of the patients experienced serious hypersensitivity reactions or demonstrated a humoral response against either the antibody or DM1 component of IMGN901. Sustained partial response (PR) was documented in 1 patient treated at 140 mg/m2/week and 3 minor responses (MR) were reported in 1 patient each at doses of 60, 90, and 112 mg/m2/week. Of the 23 patients receiving any dose level of IMGN901, 8 remained on IMGN901 treatment for at least 15 weeks. Five of these 8 patients continued treatment on IMGN901 for at least 24 weeks, and two of these 5 patients remained on IMGN901 for at least 50 weeks. Preliminary PK results indicate an approximately linear relationship between dose and observed maximal serum concentration. Conclusion: This is the first study of IMGN901 in patients with MM. The MTD of this agent in MM patients is now defined. Our experience with IMGN901 in this clinical trial demonstrates an overall favorable safety profile. Although the primary objective of this clinical trial was to determine the MTD of single agent IMGN901, exciting single agent activity was observed in heavily pretreated MM patients. This is particularly encouraging as the duration of treatment with IMGN901 in some patients was longer than duration of treatment with prior regimens of approved agents. Clinical observations noted here (including single agent efficacy and the favorable toxicity profile) as well as findings from preclinical combination studies warrant continued investigation of this novel agent in patients with MM especially in combination with approved anti-myeloma agents/regimens such as lenalidomide and dexamethasone. Disclosures: Chanan-Khan: Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Immunogen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Jagannath:Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria; Merck: Honoraria. Miller:Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Guild:ImmunoGen, Inc: Employment. Zildjian:ImmunoGen, Inc: Employment. Qin:ImmunoGen, Inc.: Employment. O'Leary:ImmunoGen, Inc.: Employment.

scholarly journals Expression of Apoptosis-Regulating Proteins in Chronic Lymphocytic Leukemia: Correlations With In Vitro and In Vivo Chemoresponses

Blood ◽  
1998 ◽  
Vol 91 (9) ◽  
pp. 3379-3389 ◽  
Author(s):  
Shinichi Kitada ◽  
Janet Andersen ◽  
Sophie Akar ◽  
Juan M. Zapata ◽  
Shinichi Takayama ◽  
...  
Keyword(s):  
Cell Death ◽  
Chronic Lymphocytic Leukemia ◽  
Caspase 3 ◽  
Single Agent ◽  
White Blood Cells ◽  
Lymphocytic Leukemia ◽  
In Vitro Chemosensitivity ◽  
Apoptotic Protein

B-cell chronic lymphocytic leukemia (B-CLL) represents a neoplastic disorder caused primarily by defective programmed cell death (PCD), as opposed to increased cell proliferation. Defects in the PCD pathway also contribute to chemoresistance. The expression of several apoptosis-regulating proteins, including the Bcl-2 family proteins Bcl-2, Bcl-XL, Mcl-1, Bax, Bak, and BAD; the Bcl-2–binding protein BAG-1; and the cell death protease Caspase-3 (CPP32), was evaluated by immunoblotting using 58 peripheral blood B-CLL specimens from previously untreated patients. Expression of Bcl-2, Mcl-1, BAG-1, Bax, Bak, and Caspase-3 was commonly found in circulating B-CLL cells, whereas the Bcl-XL and BAD proteins were not present. Higher levels of the anti-apoptotic protein Mcl-1 were strongly correlated with failure to achieve complete remission (CR) after single-agent therapy (fludarabine or chlorambucil) (P = .001), but the presence of only seven CRs among the 42 patients for whom follow-up data were available necessitates cautious interpretation of these observations. Higher levels of the anti-apoptotic protein BAG-1 were also marginally associated with failure to achieve CR (P = .04). Apoptosis-regulating proteins were not associated with patient age, sex, Rai stage, platelet count, hemoglobin (Hb) concentration, or lymph node involvement, although higher levels of Bcl-2 and a high Bcl-2:Bax ratio were correlated with high numbers (>105/μL) of white blood cells (WBC) (P = .01; .007) and higher levels of Bak were weakly associated with loss of allelic heterozygosity at 13q14 (P = .04). On the basis of measurements of apoptosis induction by fludarabine using cultured B-CLL specimens, in vitro chemosensitivity data failed to correlate with in vivo clinical response rates (n = 42) and expression of the various apoptosis-regulating proteins. Although larger prospective studies are required before firm conclusions can be reached, these studies show the expression in B-CLLs of multiple apoptosis-regulating proteins and suggest that the relative levels of some of these, such as Mcl-1, may provide information about in vivo responses to chemotherapy. In vitro chemosensitivity data, however, do not appear to be particularly useful in predicting responses in B-CLL.

scholarly journals Venetoclax Synergizes with the RNA-Directed Nucleoside Analog 8-Chloro-Adenosine in Acute Myeloid Leukemia in Vitro and In Vivo

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 22-23
Author(s):  
Ralf Buettner ◽  
Le Xuan Truong Nguyen ◽  
Corey James Morales ◽  
Lisa S Chen ◽  
Timothy Synold ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Single Agent ◽  
Inhibitory Effect ◽  
Nucleoside Analog ◽  
Research Support ◽  
Advisory Committees

Relapse of acute myeloid leukemia (AML) is attributed to the persistence of quiescent leukemia stem cells (LSCs). Bcl-2 inhibition has been shown to target primitive leukemia progenitors. Venetoclax (VEN) is a FDA-approved Bcl-2-selective inhibitor for the treatment of AML. Although the activity of single agent VEN in AML patients (pts.) is modest, clinical efficacy in newly diagnosed, older pts. unfit for intense chemotherapy has been shown when VEN is combined with the hypomethylating agents (HMAs) azacytidine and decitabine or with low-dose nucleoside analog cytarabine. We have recently shown that VEN in combination with HMAs augments oxidative stress in AML cells and provided a molecular mechanism for the VEN-HMA-regulated NF-E2-related factor 2 (Nrf2) antioxidant pathway that could explain the results observed in early clinical studies in AML. Although about 70% of pts. initially respond to these VEN treatment regimens, about 30% of pts. do not and diminished efficacy of VEN combination treatments have been observed in pts. harboring poor-prognosis markers such as FLT3-ITD. In addition, future relapse of a percentage of pts. treated with VEN combinations is expected. Thus, novel treatment options for are urgently needed. We previously reported that the ribose containing, RNA-directed nucleoside analog 8-chloro-adenosine (8-Cl-Ado) demonstrates cytotoxic activity against AML cells and LSCs in vitro and in vivo, without significantly affecting normal hematopoietic stem cells. Importantly, our initial, unpublished results from a phase I/II clinical trial with single agent 8-Cl-Ado in pts. with refractory/relapsed AML demonstrate encouraging clinical benefits. Moreover, we have reported that FLT3-ITD AML is particularly sensitive to 8-Cl-Ado, thus suggesting 8-Cl-Ado plus VEN as a potential novel therapeutic regimen for treatment of AML. We here report that the VEN plus 8-Cl-Ado combination inhibited in vitro growth and induced apoptosis in AML primary cells, LSCs and cell lines significantly more compared to treatment with the individual agents. For in vitro cell growth studies, combination indices of &lt;1 for all experimental and calculated drug concentrations demonstrated strong synergy between the two drugs in 2 human AML cell lines (MV4-11 and KG-1a) and in AML cells isolated from 2 pts. Moreover, immune compromised NSG mice engrafted with FLT3-ITD MV4-11 cells survived significantly longer when treated with VEN (20 mg·kg‒1·day‒1, daily oral) plus 8-Cl-Ado (50 mg·kg‒1·day‒1; osmotic pump), as compared to single agent or vehicle-treated mice (p&lt;0.006, VEN+8-Cl-Ado vs. 8-Cl-Ado; p&lt;0.001 VEN+8-Cl-Ado vs. VEN). LSCs depend on amino acid metabolism-driven and/or fatty acid oxidation (FAO)-driven oxidative phosphorylation (OXPHOS) for energy production. VEN is known to target LSCs through inhibition of OXPHOS by targeting amino acid uptake/metabolism. We report here that 8-Cl-Ado inhibited the FAO pathway and down-regulated the oxygen consumption rate (OCR), a marker for OXPHOS, in LSCs. However, whereas 500 nM of 8-Cl-Ado was sufficient to induce MV4-11 growth inhibition, 1 microM of 8-Cl-Ado was needed for maximum inhibitory effect on FAO. We also report that 8-Cl-Ado increased expression of the anti-apoptotic protein p53. It was previously reported that p53 induces FAO in LSCs. Knockdown of p53 by siRNA augmented the inhibitory effect of 8-Cl-Ado on FAO and OCR. Importantly, addition of VEN could completely overcome the p53-induced activation of FAO and OCR. Mechanistically, we show that 8-Cl-Ado inhibited ribosomal RNA (rRNA) synthesis, a prerequisite for cellular proliferation, through down-regulation of the transcription initiation factor 1 (TIF-IA) protein. Since TIF-1A negatively regulates p53 expression, the inhibition of TIF-1A by 8-Cl-Ado resulted in up-regulation of p53 and subsequent p53-induced upregulation of FAO and OCR, thus diminishing the suppressive effects of 8-Cl-Ado on FAO and OCR. We further show that the VEN plus 8-Cl-Ado combination strongly induced p53 signaling, as shown by activation and inhibition of downstream p21 and PCNA proteins, respectively. This combination also augmented DNA fragmentation and apoptosis in LSCs. Thus, our data suggest that the synergy seen in AML with the VEN plus 8-Cl-Ado combination can be explained at least in part due to augmented inhibition of FAO and OXPHOS and represents a promising novel treatment for AML. Disclosures Pullarkat: Dova: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Servier: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Genetech: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie, Inc.: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Marcucci:Iaso Bio: Membership on an entity's Board of Directors or advisory committees; Abbvie: Speakers Bureau; Novartis: Speakers Bureau; Pfizer: Other: Research Support (Investigation Initiated Clinical Trial); Merck: Other: Research Support (Investigation Initiated Clinical Trial); Takeda: Other: Research Support (Investigation Initiated Clinical Trial). Rosen:Celgene: Speakers Bureau; NeoGenomics: Consultancy; Seattle Genetics: Consultancy; Aileron Therapeutics: Consultancy; Novartis: Consultancy; paradigm Medical Communications: Speakers Bureau; Abbvie: Speakers Bureau; Pebromene: Consultancy.

Effective Targeting of Leukemic Cells in Children with B-Precursor Acute Lymphoblastic Leukemia Treated with Anti-CD22 (Epratuzumab). A Children’s Oncology Group (COG) Study.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2585-2585 ◽  
Author(s):  
Michael J. Borowitz ◽  
William L. Carroll ◽  
Peter C. Adamson ◽  
Mitchell S. Cairo ◽  
David M. Goldenberg ◽  
...  
Keyword(s):  
Induction Chemotherapy ◽  
Lymphoblastic Leukemia ◽  
Single Agent ◽  
Poor Response ◽  
Antigen Expression ◽  
Response To Therapy ◽  
Leukemic Cells ◽  
Color Flow

Abstract Identifying new approaches to treating relapsed ALL is a top priority because these patients fare poorly with current retrieval strategies. COG protocol ADVL04P2 is a phase I/II feasibility pilot study for children with relapsed B-precursor ALL that uses epratuzumab, a humanized anti-CD22 monoclonal antibody, in combination with conventional re-induction chemotherapy. Children whose blasts are CD22 positive first receive 4 doses of 360 mg/m2 epratuzumab as a single agent on days minus(−)14, −10, −6 and −2. Subsequently, they receive epratuzumab weekly in combination with standard re-induction chemotherapy starting on day 0. We assessed the effectiveness of epratuzumab targeting by by assaying CD22 expression on residual leukemic blasts. Peripheral blood was obtained from 15 patients 24 hours after administration of the first dose (day −13), and again at day −6 and day 0 and stained with the combination of CD10/CD22/CD45/CD19 in four color flow cytometry to permit assessment of CD22 on analytically isolated leukemic blasts. We determined quantitative expression of CD22 with a calibration kit (Quantibrite, BDBiosciences, San Jose, CA) using two PE-conjugated anti CD22 antibodies directed against different epitopes of the CD22 molecule: clone RFB4 (Caltag, Burlingame CA), directed against the same epitope as epratuzumab, and clone SHCL-1 (BDBiosciences), directed against a non-cross-reacting epitope of CD22. RFB4 binding was decreased by more than 99% within 24 hours after administration of the first dose in all patients, indicating rapid targeting of epratuzumab to leukemic cells. In all but 4 patients, levels remained low at all subsequent time points; in 2 patients expression was restored to about 15% of baseline levels by day 0, and 2 additional patients had very small (1–2%) subsets of blasts with significant expression, one at day −6 and one at day 0. In contrast to RFB4, SHCL-1 identified residual CD22 antigen expression, but SHCL-1 binding was decreased by an average of 70–75% in 14 of 15 patients at all three post-epratuzumab timepoints. The one patient with no change in SHCL-1 binding was a patient with MLL-rearranged ALL with very low levels of CD22 expression at diagnosis, and poor response to therapy. Because binding of epratuzumab to CD22 has been shown to result in antigen internalization in vitro, we interpret our findings as demonstrating in vivo internalization of CD22 with epratuzumab binding, though we cannot exclude either shedding of antigen or conformational change to block SHCL-1 sites. We conclude that epratuzumab rapidly targets CD22 on ALL blasts in vivo, though some blasts in some patients may escape over time. Targeting is associated with a physical change in CD22 antigen expression in most patients, most likely through internalization.

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