scholarly journals Navtemadlin (KRT-232), a Small Molecule MDM2 Inhibitor, Is More Effective Than Decitabine Against Myeloproliferative Neoplasm-Blast Phase in a Patient-Derived Xenograft Model

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3591-3591
Author(s):  
Xiaoli Wang ◽  
Cing Siang Hu ◽  
Virginia Gillespie ◽  
Cecile Marie Krejsa ◽  
Ronald Hoffman

Abstract Patients with myeloproliferative neoplasm-blast phase (MPN-BP) have a particularly dismal prognosis with a median survival of less than 6 months with currently available therapies (Mesa Blood 2015). Decitabine is the standard of care for MPN-BP. Recently, using xenotransplantation assays, we have shown that MPN-BP originates at the hematopoietic stem cell (SC) level (Wang Blood 2018) and that MPN-BP CD34 + cells contain higher levels of MDM2 protein compared with their normal counterparts (% of MDM2 + CD34 + cells: MPN-BP: 76.4±3.3; Normal: 17.5±6.4. P <0.05). MDM2 negatively regulates p53 activity and MDM2 inhibitors can activate p53 and induce apoptosis of TP53 WT cancer cells. As mutations or deletions of TP53 occur infrequently in MPN-BP, we examined the effects of a potent MDM2 inhibitor, navtemadlin (KRT-232; Canon Mol. Cancer Ther. 2015) and decitabine as monotherapy or in combination on the depletion or elimination of MPN-BP cells in a patient derived xenograft (PDX) model. We firstestablished the dynamics of leukemia cell recovery following a single cycle of navtemadlin treatment. Spleen cells with wild type (WT) TP53 and mutations in KRAS, RAD21, KMT2A and ASXL1 were collected from the 4 th generation of MPN-BP PDX mice. Forty days after injection of these spleen cells (4×10 5/mouse) into sublethally irradiated NSG mice, peripheral blood (PB) leukemic burden (hCD34 + cells: 0.39±0.09%) was demonstrated by flow cytometric analysis. Mice were treated with vehicle alone (n=3) or high doses of navtemadlin (100 mg/kg, n=4) by daily oral gavage on day (D) 1-7. Without navtemadlin treatment, leukemia engraftment and leukemic burden continued to increase until the mice died on D15-D23. By contrast, hCD34 + leukemic blasts were almost undetectable on D8 and remained at significantly lower levels in PB of mice treated with navtemadlin on D15, than were detected in mice receiving vehicle alone (D8: Vehicle: 1.8±1.3%; Navtemadlin: 0.1±0.1%. D15: Vehicle: 19.9±6.0%; Navtemadlin: 0.5±0.1%). These findings suggest that navtemadlin monotherapy has the potential to deplete MPN-BP blast cells and prolong survival in MPN-BP PDX mice. To achieve long-term remission and to prevent relapse, we treated MPN-BP PDX mice with multiple cycles of low (50 mg/kg, n=4) and high dose navtemadlin (100 mg/kg, n=5) at three-week intervals based on the dynamics of leukemia cell recovery following a single cycle of navtemadlin treatment. hCD34 + cells, which contain MPN-BP SCs, and hCD45 dimCD33 + leukemic blasts were reduced in the spleen, but not in the marrows of mice during 3 cycles of 100 mg/kg navtemadlin treatment. However, reduced leukemia cell burden in PB persisted during 3 cycles of navtemadlin treatment and was associated with a prolongation in survival, which was dose-dependent (Mean survival after transplantation: Vehicle: 64.0 days; 50mg/kg navtemadlin: 86.0 days; 100mg/kg navtemadlin: 98.3 days). We then examined if a combination of navtemadlin and decitabine is more effective than single agent therapy in depleting MPN-BP SCs. Again, navtemadlin at 100 mg/kg significantly reduced the leukemia cell burden in mouse PB on C1D8 (hCD34 + cells: Vehicle: 4.1±0.8%; Navtemadlin: 0.6±0.2%, an 85% decrease. hCD45 dimCD33 + cells: Vehicle: 1.4±0.3%; Navtemadlin: 0.04±0.03%, a 97% decrease. P <0.001 for both), which persisted during 2 cycles of treatment. By contrast, multiple cycles of decitabine monotherapy (2.5mg/kg, IP, 3 times/week in 21-day cycles) resulted in a modest reduction in hCD34 + cells and hCD45 dimCD33 + cells (11.4% and 30.1% decrease, respectively) in PB of MPN-BP PDX mice, and did not reduce these cells in either the spleen or bone marrow on C1D8. Finally, addition of decitabine to navtemadlin did not further deplete either MPN-BP SCs or leukemia cells and did not improve survival of MPN-BP PDX mice, as compared to treatment with navtemadlin alone. Mean survival after transplantation in the combination study was: Vehicle: 55.5 days; navtemadlin: 70.3 days; Decitabine: 56.3 days; Combination: 64.0 days. Furthermore, toxicity (body weight loss, intestinal pathology) was observed in mice receiving high dose of navtemadlin and decitabine simultaneously, but not when either drug was administered alone. In conclusion, navtemadlin monotherapy, which activates p53, depletes leukemia cell counts and prolongs survival of MPN-BP PDX mice and is a promising agent for patients with WT TP53 MPN-BP. Disclosures Krejsa: Kartos Therapeutics, Inc.: Current Employment. Hoffman: AbbVie Inc.: Other: Data Safety Monitoring Board, Research Funding; Kartos Therapeutics, Inc.: Research Funding; Protagonist Therapeutics, Inc.: Consultancy; Novartis: Other: Data Safety Monitoring Board, Research Funding.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2258-2258
Author(s):  
Tomer M Mark ◽  
Adriana C Rossi ◽  
Roger N Pearse ◽  
Morton Coleman ◽  
David Bernstein ◽  
...  

Abstract Abstract 2258 Background: Prior use of lenalidomide beyond 6 cycles of therapy in the treatment of multiple myeloma (MM) has been shown to negatively impact stem cell yield, but this phenomenon can be overcome with the addition of high-dose cyclophosphamide to standard G-CSF mobilization. We hypothesized that the use of plerixafor (Mozobil®) would compare similarly to chemotherapy in rescuing the ability to collect stem cells in lenalidomide-treated myeloma. Methods: We performed a retrospective study comparing the efficacy of plerixafor + G-CSF mobilization (PG) to chemotherapy + G-CSF (CG) (either high-dose cyclophosphamide at 3g/m2 or DCEP [4-day infusional dexamethasone/ cyclophosphamide/ etoposide/cisplatin]) in 49 consecutive stem cell collection attempts in patients with MM exposed to prior lenalidomide. The primary endpoint was the ability to collect sufficient stem cells for at least two transplants (minimum 5×106 CD34+ cells/kg), comparing results in terms of total exposure to lenalidomide and time elapsed from lenalidomide exposure until the mobilization attempt. The secondary endpoint was number of apheresis days required to meet collection goal. Resilts: Twenty-four patients underwent PG mobilization and twenty-five with CG (21 with G-CSF + cyclophosphamide, 4 with G-CSF+DCEP). The two groups did not differ in terms of total amount of lenalidomide exposure: median number of lenalidomide cycles for patients mobilized with PG was 6.5 (range 1.2–86.6), vs. 6 (range 2–21.6), for patients mobilized with CG (P = 0.663). The median time between mobilization and last lenalidomide dose was also similar between the two groups: 57.5 (range 12–462) days for PG vs. 154 (range 27–805) days for CG (P = 0.101). There was an equivalent rate of successful collection of 100% for PG and 96% for CG, P = 0.322. One patient failed collection in the CG group due to emergent hospitalization for septic shock during a period of neutropenia; no patient collected with PG had a serious adverse event that interrupted the collection process. Stem cell yield did not differ between the two arms (13.9 vs. 18.8 × 106 million CD34+ cells/kg for PG vs. CG respectively, P = 0.083). Average time to collection goal was also equal, with a median of time of 1 day required in both groups, (range 1–2 days for PG, 1–5 days for CG, P = 0.073). There was no relationship between amount of lenalidomide exposure and stem cell yield with either PG (P = 0.243) or CG (P = 0.867). Conclusion: A plerixafor + G-CSF mobilization schedule is equivalent in efficacy to chemotherapy + G-CSF in obtaining adequate numbers of stem cells for two autologous stem cell transplants in patients with MM exposed to lenalidomide; however, PG may be a less toxic approach than chemomobilization. Number of lenalidomide cycles has no impact on chances of stem cell collection success using either method. Disclosures: Mark: Celgene Corp: Speakers Bureau; Millenium Corp: Speakers Bureau. Zafar: Celgene Corp: Speakers Bureau. Niesvizky: Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Millenium: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Onyx: Consultancy, Research Funding.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 4516-4516
Author(s):  
Esha Kaul ◽  
Gunjan L Shah ◽  
Chakra P Chaulagain ◽  
Raymond L. Comenzo

Background Risk-adapted melphalan and stem cell transplant (SCT) is standard initial therapy for a minority of patients with systemic AL amyloidosis (Blood 2013;121: 5124; Blood 2011;118: 4298). Stem cell mobilization is often accomplished with high dose G-CSF (16μg/kg/d) (Blood 2011;118:4346). In the current era with effective new agents such as bortezomib, many AL patients are receiving initial therapy and achieving profound rapid cytoreduction with organ improvement (Blood 2012;119:4391; Blood 2011;118:86). But not all patients respond and in some cases the duration of response is limited. In addition, the use of SCT for consolidation after an initial response, although reasonable, has not been systematically evaluated. Whether SCT is employed as consolidation or as a second- or third-line option, the efficacy and tolerance of mobilization become important issues. Because AL patients have organ involvement limiting chemotherapy-based mobilization options, we decided to explore the option of Plerixafor and G-CSF for stem cell mobilization, based on the phase III experience in MM (Blood 2009;113:5720). We now report the first experience with this mobilization approach in AL. Patients and Methods Patients were evaluated and diagnosed by standard criteria including, in all cases, tissue biopsies showing amyloidosis. They were mobilized and collected between 4/16/12 and 6/19/13 with G-CSF 10μg/kg/d subcutaneously (SC) for 5 days (continued through collection process) and Plerixafor adjusted for renal function starting on day 4 and continuing until collection was completed. Results We report on 10 patients whose median age at mobilization was 58 years (range 46-72), 60% of whom were men. Median number of organs involved was 2 (range 1-3). Heart and kidneys were the most frequently involved organs (7 patients in each group). Median time from diagnosis to mobilization was 9 months (range 2-123). Eight patients had received prior bortezomib-based therapy. The median number of cycles was 3 (range 0-6). One had received a prior MEL 140 transplant 10 years prior and had relapsed, and 2 were treatment naïve, one of whom was 1 year status post orthotopic heart transplant. At the time of mobilization, 3 patients had non-responsive hematologic disease, 3 had achieved PR, 1 VGPR and 1 had achieved CR. Five patients had a creatinine ≥ 1.5 mg/dL including 2 patients on hemodialysis. The target cell dose was 10x106CD34/kg for all but one patient (with previous history of transplantation). The median number of collections was 2 (range 2-3). On day one, the median number of CD34+ cells collected per kg was 3.6 x106 (0.4-6x106) and on day two 6.4 x106 (2.7-19x106). The median total CD34+ cells collected per kg was 12.5x106 (5-18x106). Two patients had grade 1 bleeding from the catheter site during apheresis and one patient had dyspnea with suspected fluid overload which responded to a single dose of intravenous furosemide. There were no significant toxicities observed with Plerixafor in mobilization. All patients went on to receive high dose chemotherapy with melphalan followed by autologous stem cell transplant. The median length of hospital stay was 25 days (18-32). The median stem cell dose infused was 7.6x106CD34/kg and median days to ANC > 500 was 11 (10-22), to platelets > 20K untransfused 22 (15-44) and to lymphocytes > 500/μl 14.5 (11-25). One patient who had VOD and persistent thrombocytopenia was given the remainder of his stem cells on day +31 with full recovery and normalization of the blood counts by day +65. Conclusions In the era of more effective initial therapies, an era in which AL patients are living longer, many with moderate organ damage, mobilization with Plerixafor and G-CSF was well tolerated and made it possible to collect ample numbers of CD34+ cells with limited leukaphereses in previously treated patients and in those with advanced renal failure. This approach not only allowed the collection of sufficient CD34+ cells for optimal immediate stem cell dosing but also permitted the cryopreservation of aliquots for post-SCT boost and potentially for future cell-based therapies. Disclosures: Comenzo: Millenium: Membership on an entity’s Board of Directors or advisory committees, Research Funding; Prothena: Research Funding; Teva: Research Funding.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 312-312
Author(s):  
Mhairi Copland ◽  
Daniel Slade ◽  
Graham McIlroy ◽  
Gillian Horne ◽  
Jennifer Byrne ◽  
...  

Abstract Background Outcomes for patients with blast-phase chronic myeloid leukaemia (BP-CML) are extremely poor, and allogeneic stem cell transplantation (alloSCT) represents the only opportunity for cure. Crucially, long-term survival post-transplant depends on first attaining a return to chronic phase though salvage treatment. Novel strategies that improve response and can optimise transplant outcomes are therefore required. In the era of tyrosine kinase inhibitors (TKIs), BP-CML has become an orphan disease. Consequently, the prospective trials needed to guide clinical practice are rarely attempted. We now report the final results of the prospective MATCHPOINT trial which uses an innovative EffTox design to investigate the activity and tolerability of the TKI ponatinib in combination with high-dose chemotherapy, to improve remission status and transplant outcomes in BP-CML. Methods and patients Between March 2015 and April 2018, 17 patients were recruited through the UK Trials Acceleration Programme to this dose-finding, seamless phase I/II trial of daily ponatinib combined with fludarabine, cytarabine, granulocyte colony-stimulating factor and idarubicin (PON-FLAG-IDA) salvage therapy. We employed EffTox, an advanced Bayesian method to simultaneously consider response to treatment (efficacy) and dose-limiting toxicity (DLT) in all treated patients, providing a single measure of clinical utility, which then informed the subsequent dose level recommendation. The primary objective was to determine the optimal dose of ponatinib, in combination with chemotherapy, as determined by the EffTox model. The primary outcomes were attainment of a second chronic phase and occurrence of a DLT. Secondary outcomes investigated the toxicity of combination therapy, alloSCT outcomes, and survival. The median follow-up of trial patients is 41 months. Results Nine patients completed one cycle of PON-FLAG-IDA, a further eight patients completed both planned cycles. Using an EffTox analysis, the optimal dose of ponatinib was determined as 30mg once daily. Eleven patients achieved a return to chronic phase and four experienced a DLT, fulfilling the pre-specified criteria for clinically relevant efficacy and toxicity. After PON-FLAG-IDA salvage, eight patients attained complete cytogenetic response and five major molecular response (MMR). The most common grade 3-4 non-hematologic toxicities were febrile neutropenia (29% of patients), lung infection (24%), fever (18%) and hypocalcaemia (18%). Three patients experienced treatment-related mortality. Twelve patients proceeded to alloSCT, of whom seven are alive after median 36 months post-transplant follow-up. Only one of the five patients achieving MMR relapsed post-alloSCT, neither of the other relapsing patients achieved a second chronic phase pre-transplant. Median overall survival (OS) of the whole cohort was 12 months (95% confidence interval 6 months to non-calculable), median OS of patients undergoing alloSCT has not been reached. Conclusions Ponatinib has shown that it can be safely combined with high-dose chemotherapy to achieve a return to chronic phase in patients with BP-CML, and represents an effective novel treatment strategy in this high-risk population. Responding patients subsequently undergoing alloSCT can benefit from long-term disease-free survival. The EffTox method enabled very efficient data usage from this high-risk patient population, and is a model for investigating novel therapies in other ultra-orphan cancers. Figure: Overall survival of the MATCHPOINT cohort Figure 1 Figure 1. Disclosures Copland: Incyte: Honoraria, Research Funding, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau; Jazz: Honoraria, Speakers Bureau; Astellas: Honoraria, Speakers Bureau; Cyclacel Ltd: Research Funding. Byrne: Incyte: Honoraria. Rothwell: Novartis: Honoraria; Incyte: Honoraria; Pfizer: Honoraria; Daiichi Sankyo: Honoraria. Brock: Eli Lily: Honoraria; Invex Therapeutics: Honoraria; Merck: Honoraria; Roche: Honoraria; AstraZeneca: Current holder of individual stocks in a privately-held company; GSK: Current holder of individual stocks in a privately-held company. De Lavallade: Pfizer, Novartis.: Honoraria; Bristol Myers Squibb, Incyte: Honoraria, Research Funding. Craddock: Novartis Pharmaceuticals: Other: Advisory Board ; Celgene/BMS: Membership on an entity's Board of Directors or advisory committees, Research Funding. Clark: Novartis: Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Pfizer: Honoraria. Smith: Daiichi Sankyo: Speakers Bureau; Pfizer: Speakers Bureau; ARIAD: Honoraria. Milojkovic: Novartis: Honoraria, Speakers Bureau; Bristol-Myers Squibb: Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau; Incyte: Honoraria, Speakers Bureau. Yap: Faron Pharmaceuticals: Honoraria; Celgene: Honoraria. OffLabel Disclosure: Ponatinib for the treatment of blast-phase CML


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 2812-2812
Author(s):  
Melinda Varney ◽  
Andres Jerez ◽  
Jing Fang ◽  
David Miller ◽  
Lyndsey Bolanos ◽  
...  

Abstract Abstract 2812 Myelodysplastic syndromes (MDS) are hematologic disorders defined by blood cytopenias due to ineffective hematopoiesis, altered cytogenetics, and predisposition to acute myeloid leukemia (AML). The most common cytogenetic alteration in de novo and treatment-related MDS is deletion of chromosome 5q (del(5q)). There are two commonly deleted regions (CDR) mapped to chr 5q, however the gene(s) in these regions responsible for the manifestation of del(5q) MDS are not clearly defined. A search of annotated genes revealed that TRAF-interacting protein with forkhead-associated domain B (TIFAB), a known inhibitor of TRAF6 and a novel gene identified by an in silico search for TIFA-related genes, resides within the proximal CDR on band 5q31.1. We first determined whether TIFAB is expressed in normal hematopoietic stem/progenitor cell (HSPC) by qRT-PCR. We find that expression of TIFAB is enriched in human CD34+/CD38+ and mouse lineage-/cKit+ progenitors as compared to more differentiated populations, suggesting that it plays a role in normal HSPC function. To determine whether TIFAB is implicated in del(5q) MDS, we measured TIFAB expression in del(5q) MDS patients. According to a microarray analysis, TIFAB mRNA was significantly lower in CD34+cells isolated from MDS patients with del(5q) as compared with cells from MDS patients diploid at chr 5q (Pellagatti, et al., 2006). In an independent subset of patients, we confirmed that TIFAB expression was lower in marrow cells isolated from del(5q) MDS patients. Therefore, we hypothesize that TIFAB loss results in hematopoietic defects contributing to del(5q) MDS. To determine whether deletion of TIFAB affects hematopoiesis, we used lentiviral shRNAs to knockdown TIFAB mRNA in human cord blood CD34+ cells. To mimic haploinsufficiency of TIFAB in del(5q) MDS, we selected shRNAs that result in ∼50% knockdown of TIFAB mRNA and protein. Knockdown of TIFAB in human CD34+ cells results in increased survival, a competitive growth advantage, and altered hematopoietic progenitor function. Conversely, overexpression of TIFAB in human leukemia cell lines (THP1 and HL60) results in increased basal apoptosis, delayed G1/S-phase cell cycle progression, and impaired leukemic progenitor function in methylcellulose. Since TIFAB is predicted to regulate TRAF6, we examined the role of TIFAB on TRAF6 signaling. TIFAB suppressed TRAF6 lysine (K)-63 autoubiquitination (a measure of TRAF6 activity), and decreased total TRAF6 protein levels, suggesting that TIFAB may simultaneously inhibit TRAF6 function and protein expression. Consistent with this finding, TIFAB suppressed lipopolysaccharide-induced (TRAF6-dependent) NF-kB activation, but not TNF-induced (TRAF6-independent) NF-kB activation. TIFAB-mediated inhibition of TRAF6 also coincided with reduced phospho-IKK-beta (a measure of NF-kB activation) in leukemic cells. In summary, we have identified TIFAB as a novel del(5q) MDS/AML gene involved in regulating HSPC survival, progenitor function, and cell cycle. We propose that haploinsufficiency of TIFAB results in malignant clonal cell expansion and may contribute to the MDS/AML phenotype as a consequence of increased TRAF6-mediated activation of NF-kB. Disclosures: Maciejewski: NIH: Research Funding; Aplastic Anemia&MDS International Foundation: Research Funding.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2183-2183 ◽  
Author(s):  
Lucia Brunello ◽  
Luisa Giaccone ◽  
Maria Josè Fornaro ◽  
Matilde Scaldaferri ◽  
Valter Redoglia ◽  
...  

Abstract INTRODUCTION: Autografting (auto-HSCT) is widely used for the treatment of hematological malignancies. Since 2010, Biosimilar Filgrastim (Nivestim™, Pfizer Inc.) (BioG-CSF) has been approved and introduced into clinical practice to mobilize hematopoietic stem cells (CD34+cells) and to reduce the duration of chemo-induced neutropenia. This single institution study was designed to evaluate its safety and efficacy in the setting of "real life" medical practice. METHODS: We designed a "mixed retrospetive-prospective study" to evaluate the impact of BioG-CSF on CD34+ cells collections and engraftment kinetics after autografting. Patients who received BioG-CSF were compared with a historical cohort treated with Originator G-CSF (Filgrastim or Lenograstim). Primary endopoints were CD34+ mobilizations and post auto-HSCT engraftment kinetics. Secondary objectives included transfusions requirements, duration of hospitalization and 1-year overall survival (OS). Leukapheresis (LA) was initiated when circulating CD34+ count was at least 20/uL. Day of neutrophil engraftment was defined as the first of 3 consecutive days of absolute neutrophil count (ANC) ≥ 500/ul whereas day of platelet engraftment was defined as the first of 7 consecutive days without transfusion support. RESULTS: Initially,187 patients (137/187 affected by multiple myeloma) have been enrolled in the cohort under evaluation for CD34+ mobilization kinetics. Overall, 138 and 49 patients received originator and BioG-CSF (5-10 ug/kg/day) to collect CD34+cells. All but two patients underwent chemotherapy for mobilization (high-dose cyclophosphamide in 157/187 patients). Less than 3% of patients were poor mobilizers in both cohorts. No differences between Originator and BioG-CSF cohort were observed in time from chemotherapy to first day of LA (median day 11 vs day 11 p=0.473), CD34+/ul (mean 157.3/ul vs 166.2/ul, p=0.59) and CD34+*10^6/kg recipient harvested on the first day of LA (mean 10.5*10^6/kg vs 11.1*10^6/kg, p=0.323). A higher count of white blood cells on the first day of LA was observed in patients treated with BioG-CSF (mean originator 18.6*10^9/L vs BioG-CSF 27.1*10^9/L, p=0.001). A further analysis was conducted on 175 patients (126/175 affected my multiple myeloma) for a total of 220 auto-HSCTs, evaluable for hematological recovery and clinical outcomes. Overall, 137 and 83 patients received Originator and BioG-CSF, respectively. All patients were hospitalized and prepared for the autograft with a high-dose conditioning (Melphalan 200mg/sqm in 171/220 auto-HSCTs). Infused CD34+ cells were 5*10^6/kg recipient (IQR 3.8-5.1) and 4.1*10^6/kg recipient (IQR 3.5-5.3) in the Originator and BioG-CSF cohorts. After the autograft, patients were prescribed 30-34 milliion units (MU) of Originator G-CSF and 30 MU dose of BioG-CSF starting on day +1/+3. Day +25 cumulative incidences of ANC and platelets recovery were 99.3% and 98.5% and 97.6% and 90.2% in the Originator and BioG-CSF groups, respectively (p=0.786, p=0.006). Of note, by Mann-Whitney test, no differences between cohorts were found in a)median duration of neutropenia (median 7 and 6 days, p=0.355), platelets (median 1 pool/patient in both, p=0.894) and red blood cells (median 0/patient in both, p=0.704) transfusion requirements, hospital stay (median 20 days and 21 days, p=0.33). Serial measurements of complete blood counts were performed from discharge to day +90 post auto-HSCT; no significant differences were found at any time point between the two groups. No severe adverse reactions attributable to G-CSFs were documented. Thrombocytopenia lasted longer for patients treated with BioG-CSF, however this finding did not translate into a higher transfusion requirement or bleeding episodes. Finally, 1-year OS was comparable between cohorts (p=0.699). CONCLUSIONS: In this sizable study, BioG-CSF was as effective as Originator G-CSF in mobilizing CD34+ cells as well as in treating post-transplant neutropenia in patients with hematological malignancies. Moreover, the extensive use of BioG-CSF led to a significant cost containment. Disclosures Massaia: Janssen: Other: advisory board; Gilead: Other: advisory board; Roche: Other: advisory board, research support. Cavallo:JANSSEN: Honoraria; CELGENE: Honoraria; ONYX: Honoraria. Palumbo:Janssen Cilag: Honoraria; Takeda: Employment, Honoraria. Boccadoro:Janssen: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Mundipharma: Research Funding; Abbivie: Honoraria; SANOFI: Honoraria, Research Funding; BMS: Honoraria, Research Funding; CELGENE: Honoraria, Research Funding.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2812-2812 ◽  
Author(s):  
Sebastian Kreil ◽  
Lionel Adès ◽  
Martin Bommer ◽  
Frank Stegelmann ◽  
Mark E Ethell ◽  
...  

Abstract The WHO classification (2008) defines "myeloid/lymphoid neoplasm with eosinophilia and rearrangement of PDGFRA, PDGFRB or FGFR1" as a rare subtype of myeloid neoplasms. Whilst patients with PDGFRA or PDGFRB rearrangements respond very well to imatinib, the optimal therapy for patients with FGFR1 rearrangements, which we refer to as FGFR1 fusion gene positive MLN-eo (FGFR1+ MLN-eo), remains to be defined. Encouraging in-vitro data using inhibitors of the FGFR1 tyrosine kinase prompted the implementation of ponatinib, which inhibits FGFR1, into therapeutical strategies. In a recent report, the clinical activity of ponatinib was reported in a single patient who concomitantly received high-dose chemotherapy and allogeneic stem cell transplantation (ASCT, Khodadoust et al, Leukemia 2015). We sought to evaluate efficacy of ponatinib in seven consecutive FGFR1+ MLN-eo patients. Median age was 52 years (range, 48-74) with a male predominance (n=5). Median observation time after diagnosis was 10 months (range, 5-36). All patients presented with left-shifted leukocytosis but only three patients [all with t(8;13)] had eosinophilia of >0.5 x 109/l. Bone marrow biopsy revealed a hypercellular marrow consistent with myeloproliferative neoplasm in all patients. Five patients presented with concomitantly diagnosed lymphoid neoplasms, i.e. T-lymphoblastic lymphoma (T-LBL, n=3), biclonal accelerated phase (n=1) or lymphoid blast phase of MPN/B-cell acute lymphoblastic leukemia (B-ALL, n=1). Cytogenetic analysis revealed a reciprocal translocation with involvement of chromosome band 8p11 in all patients [t(8;13)(p11;q12), n=3; t(8;22)(p11;q11), n=2; t(1;8;22)(?;p11;q11), n=1; t(6;8)(q27;p11), n=1]. On molecular level, RT-PCR identified the associated fusion genes ZMYM2-FGFR1 (n=3), BCR-FGFR1 (n=3), and FGFR1OP-FGFR1 (n=1), respectively. In one patient with T-LBL, the FGFR1 rearrangement was revealed by FISH analysis in 80% of lymph node cells indicating an origin of both MPN and T-LBL from the same progenitor/stem cell (myeloid/lymphoid stem cell neoplasm) and T-LBL as a feature of extramedullary lymphoid blast phase. All patients were initially treated with chemotherapy-based regimens including hydroxyurea (n=4) and/or high-dose chemotherapy (n=3), the latter exclusively in patients with concomitant aggressive lymphoid neoplasms. Lack of complete response, e.g. persisting features of MPN, relapse or progression led to the off-label use of ponatinib at a dose of 30mg/day (n=2) or 45mg/day (n=5). Median duration of treatment was 8 weeks (range, 2-52). A temporary partial hematologic response (control of peripheral blood cell count) was observed in 6 of 7 patients. One patient did not respond at all and died within a few weeks while on ponatinib due to progressive disease. Three of the 6 responders had cytogenetic analysis at a median of 3 months after the start of ponatinib. One patient with t(8;13) achieved a partial cytogenetic response (50% of metaphases positive after 3 months of treatment); in all other patients no cytogenetic response was observed. Four patients underwent ASCT and are in complete molecular remission and alive after a median time of 19 months (range, 8-36) after diagnosis and 13 months (range, 4-29) after ASCT. For one patient with BCR-FGFR1-positive MLN-eo without concomitant lymphoid disease ASCT is planned. One patient is on supportive care. Conclusion: Unexpectedly, response to standard dose ponatinib in FGFR1+ MLN-eo has been poor. There was either progressive disease or no evidence for sustained hematologic or cytogenetic response. However, there was also no evidence for a sustained complete remission on intensive chemotherapy in patients with full myeloid/lymphoid phenotype. Hence, ASCT currently remains the only option to achieve long-term remission and possibly cure in FGFR1+ MLN-eo. Disclosures Off Label Use: ponatinib, used as FGFR1 inhibitor. Bommer:Alexion Pharmaceuticals: Honoraria. Cross:Ariad: Consultancy, Honoraria, Research Funding; Qiagen: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding. Hochhaus:Bristol-Myers Squibb: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; ARIAD: Honoraria, Research Funding.


Blood ◽  
2011 ◽  
Vol 118 (9) ◽  
pp. 2551-2555 ◽  
Author(s):  
Elodie Pronier ◽  
Carole Almire ◽  
Hayat Mokrani ◽  
Aparna Vasanthakumar ◽  
Audrey Simon ◽  
...  

Abstract TET2 converts 5-methylcytosine to 5-hydroxymethylcytosine (5-hmC) in DNA and is frequently mutated in myeloid malignancies, including myeloproliferative neoplasms. Here we show that the level of 5-hmC is decreased in granulocyte DNA from myeloproliferative neoplasm patients with TET2 mutations compared with granulocyte DNA from healthy patients. Inhibition of TET2 by RNA interference decreases 5-hmC levels in both human leukemia cell lines and cord blood CD34+ cells. These results confirm the enzymatic function of TET2 in human hematopoietic cells. Knockdown of TET2 in cord blood CD34+ cells skews progenitor differentiation toward the granulomonocytic lineage at the expense of lymphoid and erythroid lineages. In addition, by monitoring in vitro granulomonocytic development we found a decreased granulocytic differentiation and an increase in monocytic cells. Our results indicate that TET2 disruption affects 5-hmC levels in human myeloid cells and participates in the pathogenesis of myeloid malignancies through the disturbance of myeloid differentiation.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 5822-5822 ◽  
Author(s):  
Sandra Sauer ◽  
Andreas Marco Fischer ◽  
Andrea Fraenzle ◽  
Christina Kunz ◽  
Maximilian Merz ◽  
...  

Abstract Background: Bone disease is a hallmark of multiple myeloma (MM) and destructive osteolytic bone lesions affect more than 80 % of patients resulting in pain, spinal cord compression and a reduced quality of life. Local radiation therapy (RT) is generally used to achieve rapid improvement of bone pain, control of local tumor growth and recalcification of osseous lesions. However, patients with a high tumor burden, eligible for high dose therapy and autologous stem cell transplantation (ASCT) require systemic treatment with three to four cycles of induction therapy followed by stem cell harvest and high dose therapy. So far, it remains uncertain, if RT prior to mobilization influences stem cell harvest in newly diagnosed patients with MM. Methods: We retrospectively analyzed the impact of RT on stem cell harvest and outcome in 168 transplant-eligible patients with newly diagnosed symptomatic MM (median age 57 years, range 28-73 years). All patients received RT to symptomatic lytic bone lesions before (n=114) or after (n=54) stem cell harvest and high dose therapy. A median of three cycles induction therapy was applied followed by mobilization therapy before stem cell harvest and high dose therapy. We analyzed, whether RT before stem cell collection influenced the number of leukaphereses needed to achieve stem cell yield, the number of stem cells collected per leukapheresis and the total number of collected stem cells. Additionally, we investigated if timing of RT influenced progression-free (PFS) and overall survival (OS) after high-dose therapy and ASCT. Results: Patients receiving RT before stem cell harvest needed more than one leukapheresis to collect the planned number of stem cells (before: 68.8%; after: 44.2%; p=0.09). The median number of stem cells collected per leukapheresis was significantly lower in patients treated with RT before harvest (before: 2.6 x 106 CD34+ cells per kg / bodyweight, after: 3.8 x 106 CD34+ cells per kg / bodyweight; p<0.001). Also the total median number of collected stem cells was significantly lower in the group treated with RT before stem cell harvest (before: 9.0 x 106 CD34+ cells per kg/bodyweight, after: 10.3 x 106CD34+ cells per kg/bodyweight; p<0.02). Patients treated with RT after stem cell harvest showed a longer PFS (48.9 months) compared to the group receiving RT before harvest (36.3 months; p=0.09). No effect on OS was observed. Conclusion: We demonstrate that RT before stem cell harvest negatively influences stem cell collection in patients with symptomatic MM. Furthermore, we observed a negative trend towards shorter PFS in the group treated with RT before stem cell collection. Therefore, we suggest applying RT after stem cell mobilization in transplant-eligible patients with MM if clinically possible. Disclosures Wuchter: Sanofi: Honoraria; ETICHO: Consultancy, Honoraria. Goldschmidt:Janssen-Cilag: Honoraria, Research Funding, Speakers Bureau; Polyphor: Research Funding; Celgene: Honoraria, Research Funding, Speakers Bureau; Novartis: Honoraria, Research Funding, Speakers Bureau; Chugai: Research Funding, Speakers Bureau; Onyx: Consultancy, Speakers Bureau; Millenium: Consultancy, Speakers Bureau.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 21-21
Author(s):  
Erika Morsia ◽  
Naseema Gangat ◽  
James M. Foran ◽  
Jeanne M. Palmer ◽  
Michelle A Elliott ◽  
...  

Introduction: Myeloproliferative neoplasms (MPN), including primary myelofibrosis (PMF), essential thrombocythemia (ET) and polycythemia vera (PV), have a propensity to evolve into blast phase myeloproliferative neoplasm (BP-MPN) with a 20-year incidence rate of 9.3 %, 3.9% and 2.6%, respectively. (Szuber et al., 2019)Treatment options for BP-MPN are limited and the prognosis of these patients is dismal with a median survival of only 3.6 months and 5-year survival rate of &lt;5%.(Tefferi et al., 2018) Considering the recent reported data on the efficacy of venetoclax when combined with hypomethylating agents (HMA) in acute myeloid leukemia (AML) in both relapsed/refractory and newly diagnosed unfit patients, we have extended such combination therapy for patients with BP-MPN. Methods: We retrospectively analyzed 14 consecutive BP-MPN patients who received venetoclax plus HMA therapy between August 2018 and June 2020. We collected data regarding clinical characteristics of chronic phase MPN and BP-MPN, cytogenetic and leukemia mutation profile, efficacy and outcome. Oral venetoclax was administered in combination with azacitidine 75 mg/m2 days 1-7 (5 patients) or decitabine 20 mg/m2 days 1-5 (9 patients). Venetoclax dose was adjusted based on drug interactions particularly with azole antifungal prophylaxis. Diagnostic, risk and response assignments were according to the 2017 European LeukemiaNet (ELN) criteria.(Döhner et al., 2017) Minimal residual disease (MRD) assessment by flow cytometry, karyotype or next-generation sequencing (NGS) was performed in a subset of patients. Results: Patient characteristics at time of leukemic transformation, treatment details, response rates and overall outcome are shown in Table 1. Median age of patients was 67 years (range 48-81) with poor-risk cytogenetics in 69% of patients. JAK2 was mutated in 10 patients (71%) and CALR in 2 (14%); other mutations included TP53 in 5 patients (36%), TET2 in 4 (29%), KRAS in 3 (21%), IDH1/2 in 3 (21%), ASXL1 in 2 (14%) and U2AF1 in 2 (14%). Eight patients (57%) received venetoclax and HMA combination therapy upfront for their BP-MPN, 2 patients (14%) had failed HMA therapy previously and one patient had prior allogeneic hematopoietic stem cell transplant (AHSCT). Two patients (14%) presented with myeloid sarcoma; one of these two patients documented partial resolution of the extramedullary tumor by imaging studies, after treatment with venetoclax plus HMA. Among the remaining 12 patients, overall response rate (ORR) was 42% (n=5) and included complete remission (CR) in 3 patients (25%) and partial remission (PR) in another 2 (17%). The best response to therapy was seen after a median of 1 month (range, 1-2). Among 3 CR responders, 2 (66.6%) had minimal residual disease negative by NGS and not evidence of preceding MPN, then they successfully transitioned to AHSCT, while the third CR patient at the time of best response showed persistence of the TP53 mutation. Additionally, one PR patient subsequently relapsed and received salvage chemotherapy followed by AHSCT. (Table 2) Although data is limited by the small cohort and short follow up when the outcome of patients treated with venetoclax in combination with HMA were compared to Mayo Clinic's historical control of patients with BP-MPN treated with HMA alone (n=26) or intensive chemotherapy (n=69), there was higher CR rate in patients treated with venetoclax and HMA (25%) compared to those receiving HMA alone (4%; p=0.048) but not to those receiving intensive chemotherapy (35%; p&lt;0.0001). Moreover, the intensive chemotherapy cohort showed 24% of CR with incomplete hematologic recovery (CRi) not seen in patients receiving HMA alone or HMA with venetoclax (Figure1). Conclusions: The relatively high rate of complete response observed in our patients with BP-MPN were similar to those reported in a pivotal study of elderly unfit AML patients treated upfront with venetoclax + HMA with overall response rates of 68%.(DiNardo et al., 2019) Furthermore, responders included patients with adverse molecular risk factors who usually respond poorly to conventional chemotherapy (i.e. TP53 mutated patients). Our observations provide preliminary evidence for the potential efficacy of venetoclax and HMA combination therapy in BP-MPN with the goal of achieving CR/CRi followed by consolidative AHSCT wherever possible to provide durable remission and meaningful survival benefit. Disclosures Foran: Agios: Honoraria, Research Funding; Trillium: Research Funding; Takeda: Research Funding; Kura Oncology: Research Funding; Aptose: Research Funding; Aprea: Research Funding; Actinium: Research Funding; Boehringer Ingelheim: Research Funding; Abbvie: Research Funding; BMS: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Servier: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Revolution Medicine: Consultancy; Xencor: Research Funding; H3Biosciences: Research Funding.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 57-57
Author(s):  
Shira Rosenberg ◽  
Andrea Kubas-Meyer ◽  
Neelang Parghi ◽  
Nathaniel D. Omans ◽  
Neville Dusaj ◽  
...  

Abstract Interferon-alpha (IFN), the first approved immunotherapy for cancer, remains an effective therapy for patients with myeloproliferative neoplasms (MPN). The mechanisms of action of IFN on MPN cells are poorly understood, particularly in patients with CALR mutated (MUT) MPNs, who often exhibit clinical but not molecular responses. Previously, by developing Genotyping of Transcriptomes (GoT) that captures mutation status and single-cell RNA-seq (scRNA-seq) in high-throughput, we observed that CALR mutations led to cell identity-dependent effects on CD34 + cells, including a strong megakaryocytic progenitor (MkP) differentiation bias and fitness. We hypothesized that the IFN effects may be cell identity and mutation status dependent; thus we applied GoT to serial bone marrow aspirates (BM) from 5 patients with CALRmutated ET treated with pegylated-IFN-alfa2a who participated in MPD-RC-111/112 clinical trials. To capture the transcriptional impact of IFN, we removed experimental batch effects with Cell Hashing, in which CD34 + cells from serial BM were uniquely labeled and combined for the same GoT experiment (Fig. 1A). Cell clustering based on transcriptomic data alone revealed that the cells on active treatment clustered based on cell identity and IFN effects (Fig. 1B). When off therapy for 3 weeks, the strong transcriptional effects of IFN were largely lost (Fig. 1B). Next, we batch corrected and integrated across time points for each BM sample (Fig. 1C). We observed that IFN caused large shifts in the composition of wildtype (WT) and MUT cell subsets (Fig. 1D). IFN resulted in a dramatic expansion of WT lymphoid progenitors with a corresponding diminution of other progenitors (Fig. 1E). MUT cells at baseline were enriched for MkPs, compared to WT cells; after treatment, we observed an expansion of the immature myeloid (IMP) and neutrophil progenitors, with a less striking expansion of lymphoid progenitors (Fig. 1E). As IFN has been reported to induce cell cycling of murine hematopoietic progenitor cells, we examined whether a differential increase in proliferation by IFN underlies the differentiation shifts in WT and MUT cells. Cell cycle gene expression of ProB cells increased after treatment similarly in MUT and WT cells, while cell cycle expression of IMPs was increased to a greater extent in MUT cells (Fig. 1F), consistent with the differential shifts in populations. Next, we performed differential expression analysis between baseline and treated WT and MUT cells, respectively. We observed enrichment of the IFN pathways post-therapy, whereas TNF-a signaling was downregulated (Fig. 1G). Uniquely in the MUT cells, TGF-b signaling was downregulated, which may underlie improvements in marrow fibrosis following IFN therapy (Fig. 1G). Finally, as the differentiation biases of IFN persisted after discontinuation, we hypothesized that IFN results in chromatin remodeling of the earliest hematopoietic stem progenitor cells (HSPCs), with respect to transcription factor (TF) accessibility. We leveraged single nuclei chromatin accessibility (snATAC-seq) as a powerful measure of TF regulatory activities. We developed GoT-ATAC, an adaptation of the Multiome platform (10x Genomics), to capture snRNA-seq, snATAC-seq and somatic genotyping within the same cells in high-throughput (Fig. 1H). We applied GoT-ATAC to CD34 + cells from the same clinical trial cohorts (Fig. 1I, n = 3 patients: 3 baseline, 2 treated) and identified the expected enrichment of IRFs and STAT2 in treated HSPCs (Fig. 1J). Accessibility of BCL11A, critical for early lymphoid development, was increased in treated MUT and WT HSPCs. We also identified enhanced motif accessibility of PU.1 which can associate with IRF and is essential for myeloid and lymphoid differentiation. Uniquely within the treated MUT cells, we observed enhanced CEBPA motif enrichment, which regulates myeloid differentiation, together with PU.1. In conclusion, GoT revealed that IFN reshapes the differentiation landscape by promoting early lymphoid development and, uniquely in MUT cells, myeloid differentiation, providing a novel mechanism of actions underlying the effects of IFN in MPN patients. Downregulations of TNF-a and TGF-b signaling were other key molecular consequences of IFN. Lastly, GoT-ATAC demonstrated that IFN governs master regulators of hematopoietic differentiation as a function of the underlying mutational status. Figure 1 Figure 1. Disclosures Mimitou: Immunai: Current Employment. Smibert: Immunai: Current Employment. Hoffman: AbbVie Inc.: Other: Data Safety Monitoring Board, Research Funding; Novartis: Other: Data Safety Monitoring Board, Research Funding; Protagonist Therapeutics, Inc.: Consultancy; Kartos Therapeutics, Inc.: Research Funding.


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