A Phase II Open-Label, Ac220 Monotherapy Efficacy Study In Patients with Refractory/Relapsed Flt3-Itd Positive Acute Myeloid Leukemia: Updated Interim Results

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2576-2576 ◽  
Author(s):  
Jorge E. Cortes ◽  
Alexander E Perl ◽  
Catherine C. Smith ◽  
Tibor Kovacsovics ◽  
Herve Dombret ◽  
...  

Abstract Abstract 2576 FLT3-ITD mutations in Acute Myeloid Leukemia (AML) are associated with early relapse after standard chemotherapy and poor survival. AC220 is a potent, selective, oral FLT3 tyrosine kinase inhibitor that showed promising activity in FLT3-ITD+ patients (pts) in a Phase I study. This Phase II monotherapy trial was conducted to examine the safety and efficacy of AC220 monotherapy in pts with relapsed/refractory FLT3-ITD+ AML. Patients were enrolled into two cohorts: Cohort 1 enrolled pts ≥60 yrs and relapsed/refractory to 1st-line chemotherapy and Cohort 2 pts ≥18 yrs and relapsed/refractory to 2nd-line chemotherapy or hematopoietic stem cell transplantation (HSCT). A planned analysis was performed in February 2011 on the first 62 pts which comprised the exploratory group with the subsequent ∼240 pts being the confirmatory group for which the data will remain sequestered until study completion. The exploratory group was enrolled between 19 November 2009 and 25 August 2010. 53/62 (85%) pts were evaluable for efficacy (FLT3-ITD+ by central laboratory, received at least 1 dose of AC220, 1 post-tx response assessment and no major efficacy-related protocol deviations). The composite CR (CRc=CR+CRp+CRi) rate was 45% (24/53: 2 CRp, 22 CRi) and PR rate was 24% (13/53). Importantly, of the pts refractory to any prior therapy, 62% (16/26) had CRc and 19% (5/26) had PR in response to AC220. Median duration of CRc has not yet been reached in Cohort 1 and was 10.6 wks in Cohort 2. Overall, 8% (2/25) of pts in Cohort 1 and 30% (11/37) of pts in Cohort 2 underwent HSCT and were censored for duration of CRc. Median overall survival was 24.7 weeks for efficacy evaluable pts, 24.1 wks for Cohort 1 and not yet reached in Cohort 2 (pts were not censored at HSCT). At the time of the analysis 51/62 patients were off study (most commonly due to disease progression (19), HSCT (13) or adverse event (7). 55% of pts were still alive. The most common (>19%) drug-related AEs were nausea, QTc prolongation, vomiting, fatigue, dysgeusia, anorexia, febrile neutropenia, diarrhea, and dyspepsia. QTc prolongation occurred in 21 (34%) pts (Grade 3 in 11 pts, 18%). The incidence of QTc prolongation was decreased by reducing AC220 starting dose from 200 (35%) to 135 mg/day (8.3%) (males) and 90 mg/day (5.9%) (females). 15 pts (24%) experienced fatal treatment-emergent AEs; none were considered drug-related. An additional analysis will be conducted when all pts have > 1 yr follow up which will be available at the time of the meeting. These preliminary data suggest that AC220 achieves clinically meaningful reductions in marrow blasts in a substantial proportion of pts with both refractory and relapsed FLT3-ITD+ AML, and many of these pts were successfully bridged to HSCT. These encouraging efficacy results and an acceptable safety profile in this high risk population support continued clinical evaluation in mono- and combination therapy. Disclosures: Cortes: Ambit: Research Funding; Novartis: Research Funding.

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 42-43
Author(s):  
Alexander E. Perl ◽  
Qiaoyang Lu ◽  
Alan Fan ◽  
Nahla Hasabou ◽  
Erhan Berrak ◽  
...  

Background: Gilteritinib is approved for patients (pts) with relapsed/refractory (R/R) FLT3-mutated acute myeloid leukemia (AML), based on findings from the phase 3 ADMIRAL trial (Perl AE, et al. N Engl J Med. 2019). A phase 3 trial, QuANTUM-R, demonstrated the benefit of quizartinib in pts with R/R AML with FLT3 internal tandem duplication (FLT3-ITD) mutations (Cortes JE, et al. Lancet Oncol. 2019). Although eligibility criteria across both studies were similar, QuANTUM-R was more stringent as to prior therapy intensity and remission duration, which potentially enriched for higher-risk pts. We sought to describe outcomes from ADMIRAL among pts who otherwise met eligibility for QuANTUM-R. Methods: In this post-hoc analysis, a subset of pts from ADMIRAL were matched with R/R FLT3-ITD+ AML pts from QuANTUM-R on the basis of baseline characteristics and prior treatment criteria. Matched pts were either refractory to initial anthracycline-based chemotherapy or had relapsed ≤6 mos after achieving composite complete remission (CRc) with an anthracycline-based regimen. Results: Overall, 218 pts with R/R FLT3-ITD+ AML in the ADMIRAL trial (gilteritinib, n=140; salvage chemotherapy [SC], n=78) were matched with the QuANTUM-R intention-to treat (ITT) population (N=367; quizartinib, n=245; SC, n=122). Proportions of pts preselected for high-intensity SC were 66% (n=143/218) in the matched ADMIRAL ITT population and 77% (n=281/367) in the QuANTUM-R ITT populations. Demographic and baseline characteristics of the matched ADMIRAL ITT population and QuANTUM-R ITT population were similar. Median durations of exposure to gilteritinib and quizartinib were 3.8 mos and 3.2 mos, respectively, and median number of treatment cycles received were five and four, respectively. Rates of hematopoietic stem cell transplantation (HSCT) were similar in pts treated with gilteritinib (35%; n=49/140) or quizartinib (32%; n=78/245), as were the proportions of pts who resumed gilteritinib (23%; n=32/140) or quizartinib (20%; n=48/245) therapy post-HSCT. Median overall survival (OS) in pts treated with gilteritinib or quizartinib was longer than that observed with SC. After a median follow-up of 17.4 mos, median OS was 10.2 mos with gilteritinib versus 5.6 mos with SC (hazard ratio [HR]=0.573 [95% CI: 0.403, 0.814]; one-sided nominal P=0.0008). After a median follow-up of 23.5 mos, median OS with quizartinib was 6.2 mos versus 4.7 mos with SC (HR=0.76 [95% CI: 0.58-0.98]; one-sided P=0.02). After censoring for HSCT, median OS was 9.3 mos with gilteritinib versus 5.5 mos with SC (HR=0.525 [95% CI: 0.356-0.775]; nominal one-sided P=0.0005), and 5.7 mos versus 4.6 mos with quizartinib versus SC, respectively (HR=0.79 [95% CI: 0.59, 1.05]; one-sided P=0.05). In both QuANTUM-R and matched ADMIRAL populations, the survival benefits of quizartinib and gilteritinib compared with SC were maintained across multiple subgroups, including high FLT3-ITD allelic ratio subsets. Compared with SC, high CRc rates were observed in pts treated with either gilteritinib (57%; n=80/140) or quizartinib (48%; n=118/245). The complete remission (CR) rate with gilteritinib was 23% (n=32/140), whereas the CR rate with quizartinib was 4% (n=10/245) (Table). Median time to achieve CRc was 1.8 mos with gilteritinib and 1.1 mos with quizartinib, median duration of CRc was 5.5 mos with gilteritinib and 2.8 mos with quizartinib. The safety profiles of gilteritinib and quizartinib were generally similar, though aspartate or alanine aminotransferase elevations (any grade) were more frequent with gilteritinib (41-44%) than quizartinib (≤13%), whereas neutropenia (14% vs 34%, respectively), fatigue (24% vs 39%, respectively), and prolonged QT intervals (9% vs 27%, respectively) were more frequent with quizartinib. Conclusions: In pts with R/R FLT3-ITD+ AML and similar baseline characteristics, both gilteritinib and quizartinib were generally well tolerated and associated with improved survival and treatment response compared with SC. Responses to gilteritinib and quizartinib, as measured by CRc, were similar; blood count recovery varied between the two FLT3 inhibitors. Although cross-study comparisons have substantial limitations, the findings suggest that while remission is achieved faster with quizartinib, response may be more durable and survival potentially longer with gilteritinib. Disclosures Perl: Syndax: Consultancy, Honoraria; Leukemia & Lymphoma Society, Beat AML: Consultancy; Novartis: Honoraria, Other, Research Funding; Agios: Consultancy, Honoraria, Other; Jazz: Honoraria, Other; FORMA Therapeutics: Consultancy, Honoraria, Other; Daiichi Sankyo: Consultancy, Honoraria, Other: Writing/editorial support, travel costs for meetings, Research Funding; FUJIFILM Pharmaceuticals USA, Inc: Research Funding; New Link Genetics: Honoraria, Other; Arog Pharmaceuticals Inc: Other: uncompensated consulting, travel costs for meetings; Actinium Pharmaceuticals Inc: Consultancy, Honoraria, Research Funding; Biomed Valley Discoveries: Research Funding; Astellas: Consultancy, Honoraria, Other: writing/editorial support, travel costs for meeting presentations related to study, Research Funding; Bayer HealthCare Pharmaceuticals: Research Funding; AbbVie Inc: Consultancy, Honoraria, Other, Research Funding; Takeda: Honoraria, Other: Travel costs for meeting; Loxo Oncology Inc, a wholly owned subsidiary of Eli Lilly & Company: Consultancy, Honoraria, Other. Lu:Astellas: Current Employment. Fan:Astellas Pharma: Current Employment. Hasabou:Astellas Pharma: Current Employment. Berrak:Astellas: Current Employment. Tiu:Eli Lilly & Company: Current equity holder in publicly-traded company, Ended employment in the past 24 months; Astellas Pharma Global Development: Current Employment.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3949-3949
Author(s):  
Paolo Strati ◽  
Hagop M Kantarjian ◽  
Aziz Nazha ◽  
Gautam Borthakur ◽  
Naval G. Daver ◽  
...  

Abstract Background Acute Myeloid Leukemia (AML) and Myelodysplastic Syndrome (MDS) affect primarily elderly pts. Their treatment with aggressive chemotherapy is frequently challenging. Moreover, pts with FLT3 mutations have very poor prognosis. We hypothesized that the combination of midostaurin, a FLT3 inhibitor, and 5-AZA, a hypomethylating agent, may be an effective and safe regimen. Methods Both untreated (8) and previously treated (36) pts with AML or MDS were eligible for this study, regardless of FLT3 mutation and prior exposure to FLT3 inhibitors. Pts received 5-AZA 75 mg/mq subcutaneously or intravenously on day 1-7 and midostaurin 25 mg bid (in cohort 1 of phase I) or 50 mg bid (in cohort 2 of Phase I and in Phase II) orally on day 8-21 during the first cycle and continuously thereafter, for 12 cycles of 28 days duration. Cytogenetic risk was defined according to MRC criteria. Differences between categorical variables were compared by the chi2 test. CR duration (CRD) was calculated from the time of CR achievement until relapse and estimated by the Kaplan-Meier method and compared by the log-rank test. Results Fourty-four pts were enrolled, 13 included in Phase I and 31 in Phase II. Baseline pts’ characteristics are shown in the Table. Thirty-eight pts (86%) received 50 mg bid of midostaurin, and 6 (14%; Phase I) received 25 mg bid. The median number of administered cycles was 2 (1-9). Grade 3-4 hematological toxicities consisted of 95% neutropenia, 64% anemia and 93% thrombocytopenia. Grade 3-4 non-hematological toxicities consisted of 45% infections, 23% hypokalemia, 16% hyponatremia, 7% reduction in ejection fraction, 7% hyperuricemia, 4% hyperglycemia, 4% nausea/vomiting, 4% QTc prolongation, 4% hyperbilirubinemia, and 4% elevated AST. Eleven pts (25%) achieved a CR, 9 with incomplete platelet recovery (20%), after a median time of 13 (10-16) weeks from treatment start. Five (11%) of these pts relapsed after achieving CR. Two pts (5%) received an allogeneic stem cell transplant while on study, one in CR and one primary refractory (after a blast count drop from 27 to 7%), and they are both still in CR and alive. Among 26 pts with FLT3 ITD and no D835 mutation, 9 (35%) achieved CR/CRp. Six of 18 (33%) pts not previously exposed to FLT3 inhibitors responded. There was no significant correlation of dose with response (24% with 50 mg bid vs 33% with 25 mg bid, p=0.63). After a median follow-up of 15 (3-72) weeks, 20 pts (64%) died, 3 (7%) while on study (2 died of sepsis, 1 of unknown causes with progressive disease). The median CRD was 16 (9-23) months. Factors significantly associated with a longer CRD were male sex (p=0.04), age older than 65 years (0.03) and use of 50 mg bid of midostaurin (p=0.02). Conclusions The combination of midostaurin and 5-AZA is safe and well tolerated. Its efficacy is most noticeable among pts with FLT3 mutations. A longer response duration is observed using midostaurin at 50 mg bid dose and in elderly male pts. Disclosures: Ravandi: CELGENE: Honoraria; NOVARTIS: Honoraria. Cortes:ARIAD: Consultancy, Research Funding; ASTELLAS: Research Funding; AMBIT: Research Funding; AROG: Research Funding; NOVARTIS: Research Funding.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1443-1443
Author(s):  
Aref Al-Kali ◽  
Raoul Tibes ◽  
Jeanne Palmer ◽  
Hassan B. Alkhateeb ◽  
Mrinal M. Patnaik ◽  
...  

Abstract Background: Acute myeloid leukemia (AML) is an aggressive blood cancer with a wide range of response and relapse rates using standard chemotherapy combining anthracycline plus cytarabine (7+3). The stem cell receptor tyrosine kinase KIT is expressed on more than 10% of blasts in 95% of relapsed AML cases and mediates leukemic proliferation and has anti-apoptotic effects (Domen and Weissman 2000). AML with high KIT expression is associated with poorer outcome (Del Poeta, Venditti et al 2003). Goals: To study the efficacy and safety of combination 7+3 and nilotinib in patients (pts) with AML and KIT expression. Primary goal is to determine the complete response (CR) rate; while secondary goals include 2-year overall survival (OS) and disease free survival (DFS) in addition to safety. Methods: A single arm, Phase II study, enrolled pts at Mayo Clinic (MN and AZ). Appropriate IRB was obtained and study was registered (NCT 01806571). Pts were enrolled if they were newly diagnosed with AML with KIT (CD117) expression of ≥ 20% on myeloblasts by flow cytometry. KIT mutations were allowed. Nilotinib 300 mg twice daily was given on days 4-14 of induction and consolidation; and continuous daily maintenance therapy for up to 2 years. Cytarabine 100 mg/m2/day continuous IV x7 days plus daunorubicin 60 mg/m2 IV daily x3 days were used for induction, while consolidation used standard cytarabine 3 gm/m2 twice daily days 1, 3, 5 for a total of 4 cycles. This is a Simon 1-stage design with a safety analysis after enrolling 12 pts, and an interim analysis after enrolling 18 out of 43 pts (Al-Kali, ASH 2015) recommended to continue study accrual. Results: i)- Demographics: Thirty four pts were enrolled from July 2013 to June 2017. Median age was 59 years (range 24-69) with 71% being male. Median laboratory findings include hemoglobin of 8.8 gm/dL, platelets of 56 x109/L, white blood count of 3.3 x109/L (0.4-125), and peripheral blood blasts 17 %(0-94%). Cytogenetics were normal in 43% of the pts and favorable cytogenetics were seen in 6%(inv 16). FLT3 gene testing was done on 26 pts and was positive in 13%. KIT gene sequencing (exon 8, 9, 10, 11, 17) revealed pathogenic mutation in 1/28 cases (4%). ii)- Clinical outcome Out of all 34 pts enrolled on the study, 18 (53%) achieved CR (or CR with incomplete platelet recovery) with a median CR duration of 21.8 months. Of 26 evaluable pts, the overall CR rate was 69%. 4 of the 18 pts (22%) who achieved remission needed a second induction. One pt died due to liver failure (had only one dose of nilotinib and toxicity was attributed to daunorubicin). 13 (38%) pts proceeded to allogeneic stem cell transplant (HSCT), 12 of whom are alive and none were able to initiate nilotinib maintenance. Only 6 (1 had HSCT) out of 34 (18%) pts relapsed after achieving CR. Median DFS was 45.8 months, while median OS was 42.4 months. 2-year DFS and OS were 58% and 72%, respectively. iii)- Safety Thirty four pts were evaluated for adverse events (AE). Fourteen pts had G4 non-hematological AEs, including fourteen G4 AEs related to infection, 2 with electrolyte imbalances, 1 heart failure, 1 elevated bilirubin, 1 elevated lipase, and 1 jejunal hemorrhage. One patient had G5 liver failure. Most common (>20%) G3 non-hematological AEs were febrile neutropenia (56%), hypophosphatemia (21%), elevated ALT (21%) and hypertension (21%). Conclusion: Combination daunorubicin and cytarabine with nilotinib (DATA) appears to be safe and effective. Final results show an acceptable safety profile with most common AE being infection. Thirty day mortality was low (3%). DATA regimen has comparable CR rates of 53% (intent to treat) and 69% in evaluable pts. Relapse rates were very low at 18% with durable responses and encouraging survival rates. Figure. Figure. Disclosures Al-Kali: Novartis: Research Funding. Tibes:Novartis: Research Funding. Palmer:Novartis: Research Funding.


2021 ◽  
pp. JCO.20.02342
Author(s):  
Thomas Cluzeau ◽  
Marie Sebert ◽  
Ramy Rahmé ◽  
Stefania Cuzzubbo ◽  
Jacqueline Lehmann-Che ◽  
...  

PURPOSE TP53-mutated ( TP53m) myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) have very poor outcome irrespective of the treatment received, including 40% responses (20% complete remission [CR]) with azacitidine (AZA) alone, short response duration, and a median overall survival (OS) of approximately 6 months. Eprenetapopt (APR-246), a novel first-in-class drug, leads to p53 protein reconformation and reactivates its proapoptotic and cell-cycle arrest functions. PATIENTS AND METHODS This phase II study assessed the safety and efficacy of eprenetapopt in combination with AZA in untreated high or very high International Prognostic Scoring System-R TP53m MDS and AML patients. RESULTS Fifty-two TP53m patients (34 MDS, 18 AML [including seven with more than 30% blasts]) were enrolled. In MDS, we observed an overall response rate (ORR) of 62%, including 47% CR, with a median duration of response at 10.4 months. In AML, the ORR was 33% including 17% CR (27% and 0% CR in AML with less than and more than 30% marrow blasts, respectively). Seventy-three percent of responders achieved TP53 next-generation sequencing negativity (ie, variant allele frequency < 5%). The main treatment-related adverse events were febrile neutropenia (36%) and neurologic adverse events (40%), the latter correlating with a lower glomerular filtration rate at treatment onset ( P < .01) and higher age ( P = .05), and resolving with temporary drug interruption without recurrence after adequate eprenetapopt dose reduction. With a median follow-up of 9.7 months, median OS was 12.1 months in MDS, and 13.9 and 3.0 months in AML with less than and more than 30% marrow blasts, respectively. CONCLUSION In this very high-risk population of TP53m MDS and AML patients, eprenetapopt combined with AZA was safe and showed potentially higher ORR and CR rate, and longer OS than reported with AZA alone.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3299-3299
Author(s):  
Dennis Dong Hwan Kim ◽  
Taehyung Kim ◽  
Tracy Murphy ◽  
Steven M Chan ◽  
Mark D. Minden ◽  
...  

Introduction: A 17-gene stemness score (LSC17 score) had been reported to determine the risk of therapy resistance in acute myeloid leukemia (Nature 2016), and this was replicated successfully in 5 independent cohorts (n=908). When the patients were stratified according to the median value of the LSC17 score, allogeneic hematopoietic stem cell transplantation (HCT) did not affect overall survival (OS) from initial diagnosis for either high- or low-score patients (p=0.2 for high and p=0.06 for low LSC17 score groups). In the present study, we aimed to further perform a subgroup analysis confined to the patients receiving allogeneic HCT and determine whether the LSC17 score at leukemia diagnosis was associated with treatment outcomes including OS, leukemia-free survival (LFS), non-relapse mortality (NRM), relapse incidence (RI), and acute/chronic GVHD following allogeneic HCT. Methods and patients: Out of 452 patients with available LSC17 scores, 123 patients were included into the final analysis who received allogeneic HCT using matched (n=104, 84.6%) or mismatched/haploidentical donors (n=19, 15.4%). 80 patients were from the previous study (Nature 2016), while 43 patients were a prospectively accrued cohort during 2016-2018. Patients and transplant characteristics were: male/female (n=61/62); median age, 51 (17-73); CR status prior to HCT, CR1 (n=93, 75.6%), CR2 (n=30, 24.4%); Conditioning regimen, reduced intensity/myeloablative conditioning (n=59, 48.0% vs n=64, 52.0%); GVHD prophylaxis using post-transplant cyclophosphamide (PTCy; n=45, 36.6%) or T cell depletion (n=62, 50.4%); Cytogenetic risk, favorable (n=10, 8.1%), intermediate (n=70, 56.9%), adverse (n=26, 21.1%), inconclusive or not done (n=17, 13.8%). The LSC17 score for each patient was measured in a diagnostic sample using a NanoString assay and compared to the high/low threshold of a reference AML cohort (Ng et al, Nature 2016 and unpublished data). Transplant outcomes were compared according to the LSC17 risk group for OS, LFS, NRM and RI. Univariate and multivariate analyses were conducted for OS and LFS using Cox's proportional hazard model or for NRM and RI using Fine-Gray model, respectively. The following variables were included in the model: the LSC17 score group (high vs low LSC17 score), chronic GVHD, CR status (CR2 vs CR1), Cytogenetic risk (adverse vs favorable/intermediate/inconclusive), GVHD prophylaxis (PTCy vs others, T-cell depletion vs others), Age (above 60 vs others), donor type (mismatched/haploidentical vs matched donors). Results: With a median follow-up duration of 22 months among survivors after HCT, 23 patients experienced relapse (n=23, 18.7%) while 63 deaths (51.2%) were noted. Out of 123 patients, 58 (47.1%) had a low LSC17 score and 65 (52.9%) had a high LSC17 score. There was no difference in the distribution of LSC17 scores between the group who received HCT (n=123; 0.479±0.026) vs not (n=229; 0.456±0.019; p=0.491). LFS survival was significantly better in the low LSC17 score group (51.5 vs 32.4% for 2-year LFS rate, p=0.0219), and there was a trend to higher OS rate in the low LSC17 group (48.1%) compared to the high LSC17 group at 2 years (34.2%, p=0.09). Furthermore, patients with a low LSC17 score had a significantly lower RI (14.9% vs 27.3% for 2-year relapse incidence, p=0.028). There is no difference of NRM between the groups (37.2% vs 38.2% at 2 years, p=0.647). Multivariate analysis confirmed that the high LSC17 score group was associated with worse LFS (HR 1.874 [1.080-3.249], p=0.025). However, it was not confirmed with respect to OS or relapse incidence. As expected, it was not associated with NRM. Conclusion: A low 17-gene stemness score is associated with better leukemia-free survival and lower relapse incidence after allogeneic HCT, and is suggested to be associated with OS. The high LSC17 score group may be considered for novel therapeutic strategies to reduce the risk of relapse after allogeneic HCT. Figure Disclosures Chan: Celgene: Honoraria, Research Funding; AbbVie Pharmaceuticals: Research Funding; Agios: Honoraria. Minden:Trillium Therapetuics: Other: licensing agreement. Michelis:CSL Behring: Other: Financial Support. Mattsson:Gilead: Honoraria; Celgene: Honoraria; Therakos: Honoraria. Wang:Pfizer AG Switzerland: Honoraria, Other: Travel and accommodation; Pfizer International: Honoraria, Other: Travel and accommodation; Trilium therapeutics: Other: licensing agreement, Research Funding; NanoString: Other: Travel and accommodation.


Blood ◽  
2009 ◽  
Vol 114 (24) ◽  
pp. 5034-5043 ◽  
Author(s):  
Goichi Yoshimoto ◽  
Toshihiro Miyamoto ◽  
Siamak Jabbarzadeh-Tabrizi ◽  
Tadafumi Iino ◽  
Jennifer L. Rocnik ◽  
...  

Abstract Myeloid cell leukemia-1 (MCL-1) is an essential survival factor for hematopoiesis. In humans, hematopoietic stem cells (HSCs) express MCL-1 at the highest level in response to FMS-like tyrosine kinase-3 (FLT3) signaling. We here show that this FLT3-dependent stem cell maintenance system also plays a critical role in survival of leukemic stem cells (LSCs) in acute myeloid leukemia (AML). The CD34+CD38− LSC fraction expresses high levels of FLT3 as well as MCL-1, even compared with normal HSCs. Treatment with FLT3 ligand induced further MCL-1 up-regulation in LSCs in all AML cases tested. Interestingly, the group of samples expressing the highest levels of MCL-1 constituted AML with FLT3–internal tandem duplications (ITD). In FLT3-ITD AML cell lines, cells expressed a high level of MCL-1, and an inhibition of MCL-1 induced their apoptotic cell death. A tyrosine kinase inhibitor suppressed MCL-1 expression, and induced apoptosis that was reversed by the enforced MCL-1 expression. Finally, transduction of FLT3-ITD into HSCs strongly activated MCL-1 expression through its signal transducer and activator of transcription 5 (STAT5)–docking domains. This effect was completely abrogated when STAT5 activation was blocked. Thus, the acquisition of FLT3-ITD ensures LSC survival by up-regulating MCL-1 via constitutive STAT5 activation that is independent of wild-type FLT3 signaling.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1309-1309
Author(s):  
Theresa Kretschmann ◽  
Christoph Röllig ◽  
Brigitte Mohr ◽  
Michael Kramer ◽  
Matthias Stelljes ◽  
...  

Abstract Introduction: The ELN classification of cytogenetic aberrations in acute myeloid leukemia (AML) distinguishes favorable risk, intermediate risk I and II and adverserisk. The adverse-risk group contains patients (pts) with inv(3) and t(3;3). These pts have a significantly poorer outcome compared to other cytogenetic aberrations. The MRC classification considers both pts with inv(3) and t(3;3) as well as patients with other abn(3q) as adverse risk, but excludes t(3;5). Pts with inv(3) or t(3;3) have breakpoints located on the long arm of chromosome 3 at q21 and q26. As a result of these chromosomal modifications, an enhancer-protein is deregulated and the stem-cell regulator zinc finger protein EVI1 on 3q26 is over expressed. Other 3q aberrations do not involve EVI1. We conducted a comparative analysis on the impact of abn(3q) with likely EVI1 alteration versus abn(3q) without EVI1 involvement. Analyses were done both in the entire group of abn(3q) pts and in the subgroup of pts treated with allogeneic hematopoietic stem-cell transplantation (HSCT). Methods: We performed a retrospective analysis on 163 patients with an abnormality on the q arm of chromosome 3 (abn(3q)). These pts were treated between 1996 and 2009 in three multicenter studies by the German SAL study group (AML2003, AML96, AML60+). Pts with t(3;5) were excluded (n=11). The remaining 152 patients were divided into two groups. Group 1 (EVI1) contained 56 patients with a chromosomal aberration likely to alter EVI1, i.e. t(3;3), inv(3) and abn(3)(q26). Group 2 (noEVI1) comprised the remaining 96 patients displaying other abn(3q) aberrations. We compared groups for baseline characteristics, complete remission (CR), relapse-free survival (RFS) and overall survival (OS) in total and stratified for treatment. Results: Descriptive comparison of the groups (EVI1 vs noEVI1) revealed a significantly higher WBC count (14.3 vs 4.6 Gpt/l), PLT count (62 vs 47 Gpt/l) and -7 incidence (29% vs 16%) in the EVI1 group, whereas in the noEVI1 group, complex aberrations (25% vs 74%) and 17p alterations (0% vs 24%) occurred in a higher proportion of pts. CR rates (52% vs 47%), median RFS (7 vs 6 months) and median OS (6 vs 7 months) did not differ significantly between the two groups. In order to explore the clinical behavior of the different abn(3q) aberrations in relation to allogeneic HSCT, we compared EVI1 pts (n=21) versus noEVI1 pts (n=38) who received an allogeneic HSCT at any time during treatment. Patients with aberrant EVI1 were significantly younger (median age 44 vs 52 years), had a higher incidence of -7 (29% vs 13%), but less frequent karyotype complexity (10% vs 74%) or 17p alterations (0% vs 24%). More patients in the EVI1 group achieved a first CR before HSCT (95% vs 84%). Amongst CR pts, median RFS was slightly higher in the EVI1group (9 vs 6 months). In all abn(3q) pts with allogeneic HSCT, median OS was 30 months in the EVI1 group and only 12.5 months in the noEVI1 group. According to the log-rank test, this difference did not reach statistical significance (p=0.137). The advantage in mean OS for EVI1 patients is most likely due to the higher proportion of patients transplanted in CR while the accumulation of complex karyotypes in the noEVI1 group caused more primary resistant AML cases with a rapid progression even after allogeneic HSCT. Conclusions: Although AML development may be based on different molecularbiological mechanisms in patients with different abn(3q) aberrations depending on EVI1 alteration, the prognosis of the two groups is very similar. The most likely reason is the equal balance of favorable and adverse prognostic factors between the two groups such as age, karyotype complexity, 17p alteration and -7. Patients of both groups benefit from allogeneic HSCT to a similar extent. Confirmation of these results on larger data sets is desirable and under way. Disclosures Baldus: Novartis: Research Funding. Einsele:Novartis: Consultancy, Honoraria, Speakers Bureau; Amgen/Onyx: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau. Thiede:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AgenDix GmBH: Equity Ownership.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 5176-5176
Author(s):  
Torsten Kessler ◽  
Steffen Koschmieder ◽  
Christoph Schliemann ◽  
Martina Crysandt ◽  
Jan-Henrik Mikesch ◽  
...  

Abstract Background: Patients with AML who are not eligible for intensive therapy or stem cell transplantation have a dismal prognosis. Autocrine and paracrine secretion of angiogenic and hematopoietic growth factors such as vascular endothelial growth factor in the bone marrow (BM) microenvironment may promote proliferation and survival of leukemic blasts. The oral multikinase inhibitor pazopanib was reported to exert growth inhibitory and proapoptotic effects in myeloid cells. Methods: This phase II study evaluated pazopanib (800 mg orally once daily) in patients with relapsed or refractory AML or at initial diagnosis when no intensive treatment is possible. All patients who received pazopanib for 14 days or longer were included into the analysis of safety, tolerability and efficacy. Response criteria are defined according to the Revised Recommendations of the International Working Group for Diagnosis, Standardization of Response Criteria, Treatment Outcomes, and Reporting Standards for Therapeutic Trials in Acute Myeloid Leukemia. Co-primary endpoints were cumulative response rate (CR, CRp, CRi, PR) within up to one year and reduction of BM microvessel density (MVD) on day 28. Overall survival (OS) and progression free survival (PFS, time from first dose until progression or death from any cause) were measured from the first day of treatment until death of any cause or progression of disease. Results: Between February 2012 and September 2015, 20 AML patients with a median (range) age of 76 (52 - 86) years were treated with pazopanib. The majority of patients (n = 15, 75%) had relapsed (n = 7) or refractory (n = 8) AML, five patients (25%) were enrolled with newly diagnosed AML. Median (range) ECOG performance status was 1 (1 - 3). According to ELN 2010 criteria, four patients (20%) had adverse risk, 15 (75%) had intermediate risk, and one patient (5%) had favorable cytogenetic/molecular risk. Overall, the safety profile of pazopanib was similar to that reported in previous studies. The most common AEs of any grade, related to pazopanib as assessed by the investigator, were gastrointestinal AEs, including nausea (n = 8), diarrhea (n = 6), inappetence (n = 5) and vomiting (n = 3). Two out of 20 treated patients (10%) had a partial remission (reduction of blast count > 50%) and 14 (70%) a stable disease (SD) while on pazopanib. Four patients (20%) experienced initial PD. Median PFS was 65 days (95% CI 29 - 105). After the end of study period three remarkable responses occurred on subsequent therapies such as demethylating agents resulting in one CRi and one CRp and one CR after secondary BM transplantation. All these patients had SD while on pazopanib and improved general condition allowing escalation of therapy. However, at the time of OS evaluation all patients had died due to PD and/or infections. Median OS of the treated study cohort was 191 days (95% CI 87 - 435), and 1-year survival altogether was 35%. There was no significant change in BM MVD between day 1 and day 28. Conclusion: Pazopanib was found to be safe in patients with AML not eligible for intensive therapy. The survival data are encouraging but clearly necessitate a controlled randomized clinical trial for confirmation. Clinical trial information: NCT01361334. Disclosures Stelljes: Amgen: Honoraria; JAZZ: Honoraria; MSD: Consultancy; Pfizer: Consultancy, Honoraria, Research Funding; Novartis: Honoraria. Lenz:Roche: Consultancy, Honoraria, Other: Travel, Accomodations, Expenses, Research Funding; Bayer: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis: Research Funding; Gilead: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Other: Travel, Accomodations, Expenses, Research Funding, Speakers Bureau; Celgene Corp.: Consultancy, Honoraria, Other: Travel, Accomodations, Expenses, Research Funding, Speakers Bureau. Brümmendorf:Takeda: Consultancy; Novartis: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Janssen: Consultancy; Merck: Consultancy.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 1534-1534
Author(s):  
Razan Jammal ◽  
Kathrin Krowiorz ◽  
Nadine Haetscher ◽  
Stephan Emmrich ◽  
Arefeh Rouhi ◽  
...  

Abstract Deregulated microRNA (miRNA) expression has been implicated in the pathogenesis of acute myeloid leukemia (AML). We previously showed that miR-193b is a STAT5-regulated miRNA that controls hematopoietic stem and progenitor cell (HSPC) expansion by modulating cytokine receptor signaling. Here we demonstrate that the miR-193 family members miR-193a and 193b are potent tumor suppressors in AML. Both miRNAs were downregulated in several cytogenetically-defined subgroups of pediatric and adult AML (n=202), whereas low miR-193b expression was an independent indicator for poor prognosis and survival. Accordingly, ectopic retroviral Hoxa9-Meis1 expression in HSPCs from miR-193b-/- mice resulted in a more aggressive disease with significantly shortened latency and survival as compared to miR-193bWT/WT HSPCs. Inversely, ectopic miR-193 expression in leukemic cells belonging to various AML subgroups decreased leukemic growth in vitro and prolonged survival of mice suffering from Hoxa9-Meis1-induced leukemia through a G1/S phase block. These effects were mediated by targeting c-KIT, KRAS and SOS2 - key factors of the KIT-RAS-RAF-MEK-ERK signaling cascade - as well as the downstream cell cycle regulator CCND1. Knockdown of each of these genes partially recapitulated the anti-proliferative effect of ectopic lentiviral miR-193 expression. As the tumor suppressive function is independent of patient age or AML cytogenetic background, these observations suggest an opportunistic role for miR-193 in future AML therapies. With the notion that a single miRNA can control aberrant MAPK signaling at multiple levels, restoring miR-193 expression in AML cells with constitutive activation of this cascade would assure high antileukemic efficacy, while avoiding the fast development of resistance mechanisms. Disclosures Heuser: Bayer Pharma AG: Research Funding; Novartis: Consultancy, Research Funding; BerGenBio: Research Funding; Tetralogic: Research Funding; Karyopharm Therapeutics Inc: Research Funding; Celgene: Honoraria; Pfizer: Research Funding. Mulaw:NuGEN: Honoraria. Baruchel:Jazz: Consultancy; Servier: Consultancy; Celgene: Consultancy; Novartis: Consultancy; Baxalta: Research Funding.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1516-1516
Author(s):  
Cecilia Y Arana Yi ◽  
Jorge Cortes ◽  
Stefan Faderl ◽  
Guillermo Garcia-Manero ◽  
Marina Konopleva ◽  
...  

Abstract Abstract 1516 Background: Sorafenib is a potent inhibitor of FLT3 kinase with demonstrable clinical activity in patients with acute myeloid leukemia (AML) and FLT3-ITD mutation, but not those with FLT3-D835 mutation. Objectives: To determine the long term outcome of patients with AML treated with the combination of Sorafenib, cytarabine and idarubicin, and in particular those with FLT3-ITD mutation. Method: Between October 2007 to March 2010, 62 patients with newly diagnosed, previously untreated AML, were treated with Sorafenib 400 mg orally twice daily (BID) for 7 days, cytarabine 1.5 g/m2 by continuous intravenous (IV) infusion daily for 4 days (3 days if &gt; 60 years of age), and idarubicin at 12 mg/m2 IV daily for 3 days on an IRB-approved clinical trial. After achieving remission, patients received up to 5 cycles of consolidation with sorafenib 400 mg BID continuously and abbreviated doses of cytarabine and idarubicin given at approximately one month intervals. Results: 62 patients were treated on the phase II portion of the study. Median age was 53 years (range, 18 – 66) and 12 (19%) patients were &gt; 60 years. 23 (37%) had FLT3 mutations including 17 with FLT3-ITD, 4 with FLT3-D835, and 2 with both mutations. Cytogenetics was diploid in 36 (58%), chromosome 5 and 7 deletion in 4 (6%) and 1 (2%) respectively, complex in 8 (13%), miscellaneous in 13 (21%). Median white blood cell count (WBC) at diagnosis was 7.25 × 109/L (range, 0.6 – 225), and 28 (45%) patients had WBC &gt; 10 × 109/L; among these, 12 (43 %) had FLT3-ITD. After induction, 49 (79 %) patients achieved CR and 5 (8%) CR with incomplete platelet recovery (CRp). 1 (2%) patient died before response assessment could be performed and 7 (11%) were non responders. Patients with FLT3-ITD were more likely to achieve a CR/CRp than patients without FLT3-ITD [18/19 (95%) patients vs. 36/43 (83%) patients, respectively (p=0.23)]. To date, 32 (59%) of the responders have relapsed including 10 of 18 (56%) patients with FLT3-ITD and 22 of 36 (61%) patients without FLT3-ITD (P=0.86). 35 patients received salvage therapy; 14 died after receiving salvage therapy, 11 achieved a second CR and 10 were refractory. After a median follow up of 40.6 months (range, 5.7 to 50 months), the median DFS and OS were 13 months and 29 months, respectively. Hematopoietic stem cell transplantation (HSCT) was performed in 34 (55 %) patients, including 23 in CR, and 11 with active disease. Stem cell source was from related donors in 15 (44%), unrelated donors in 9 (26%), cord blood in 7 (21%), and haploidentical donors in 3 (9%) patients. Overall, 35 (56%) patients have died; 16 (26%) had infectious complications, 12 (19%) multi-organ failure, 9 (15%) graft versus host disease, and 10 (16%) other causes with some patients having overlapping causes. Three-year disease free survival (DFS)(in patients achieving CR, n=54) and overall survival (OS) (n=62) were 34% and 47%, respectively (Figures 1 and 2). Conclusion: Combination of sorafenib, idarubicin and cytarabine is an effective regimen with durable responses in patients with newly diagnosed AML, particularly those with FLT3-ITD. Disclosures: Ravandi: Bayer: Research Funding; Onyx: Research Funding.


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