Irum Khan MD Asst. Professor University of Illinois Myelodysplastic Syndrome (MDS) and Myelofibrosis Syndromes: What’s Next? Irum Khan MD Asst. Professor University of Illinois

Landscape of genetic lesions in 944 patients with myelodysplastic syndromes Significantly mutated genes in MDS. (a) Frequency of mutations in 47 significantly mutated genes in 944 cases with different WHO subtypes, which are shown in indicated colors. (b) Frequency of gene mutations involved in common functional pathways, which are defined in Supplementary Table S3. (c) Number of gene mutations detected in different MDS subtypes. (d) Distribution of mutations/deletions of significantly mutated genes in 944 MDS cases. Haferlach et al. Leukemia 2014

Cancer cell signaling pathways and the cellular processes they regulate Cancer cell signaling pathways and the cellular processes they regulate. All of the driver genes listed in table S2 can be classified into one or more of 12 pathways (middle ring) that confer a selective growth advantage (inner circle; see main text). These pathways can themselves be further organized into three core cellular processes (outer ring). The publications on which this figure is based are provided in table S5. Bert Vogelstein et al. Science 2013;339:1546-1558 Published by AAAS

Mutations may segregate with clinical subsets Elli Papaemmanuil et al. Blood 2013;122:3616-3627

IPSS

Bejar R et al. N Engl J Med 2011;364:2496-2506. Overall Survival, According to Clinical (IPSS) Risk Category and Mutational Status Figure 4. Overall Survival, According to International Prognostic Scoring System (IPSS) Risk Category and Mutational Status. Panel A shows the overall survival of patients within each IPSS risk group. Panel B shows the overall survival of patients with mutations in one or more of the five prognostic genes (TP53, EZH2, ETV6, RUNX1, or ASXL1) as compared with patients without such mutations. Panels C through F show the overall survival of patients according to the presence and absence of prognostic mutations and according to IPSS risk group. In Panels C, D, and E, the overall-survival curve for patients in the next-highest IPSS risk group is included for the purpose of comparison. In Panel F, the comparison curve is for patients in the next-lowest IPSS risk group. P values were calculated for the log-rank comparison of overall survival between patients with mutations and those without mutations for the given IPSS risk group. The IPSS risk classification, which is based on the percentage of blasts in bone marrow, the karyotype, and the number of cytopenias (Table 2 in the  Supplementary Appendix), was recalculated for 428 of the 439 samples at the time of bone marrow sample collection (the IPSS classification could not be recalculated for 11 samples). Bejar R et al. N Engl J Med 2011;364:2496-2506.

MDS treatment algorithm. MDS treatment algorithm. Not all patients with MDS require therapy; some can be safely observed with intermittent blood count monitoring for a period of time. Once therapy is justified by the presence of symptoms, severe cytopenias, or increasing blast proportion, prognostic risk assessment can aid in selection of lower-intensity therapies vs disease-modifying treatments, including allogeneic stem cell transplantation, which is the only potentially curative approach. Clinical trial enrollment is encouraged at all phases of disease. The level of evidence supporting the recommendations in this algorithm varies, with some approaches supported by a randomized prospective trial (eg, azacitidine in higher-risk MDS, lenalidomide in del5q MDS) and others supported only by phase 2 data (eg, iron chelation) or case series (eg, androgens). G-CSF, granulocyte colony stimulating factor; sEPO, serum EPO level; TSA, thrombopoietin receptor agonist (thrombopoiesis stimulating agent). Modified from Steensma and Stone.129 ©2014 by American Society of Hematology

Mutations to guide therapy Some data to suggest TET2 mutations may predict response to hypomethylating agents Response rate to azacytidine was 82% in MUT versus 45% in WT patients (P=0.007) (Itzykson et al. Leukemia 2011) TET2 mutated mice with MDS treated with hypomethylating agent respond better to azacytidine than TET2 wild type mice. (Bejar et al. Blood 2014)

Following transplant, certain mutations retain prognostic value mutations in TP53, TET2, and DNMT3A are predictors of survival 60% of patients with MDS without these mutations were alive and disease free 3 years after HSCT. Overall survival (OS) by TP53 and DNMT3A mutation status. OS of patients (A) with and without complex karyotype and (B) with complex karyotype stratified by TP53 mutation status and compared with survival of patients with noncomplex karyotype; (C) OS and mutation distribution showing overlap between patients with TP53, TET2, and DNMT3A mutations. Each column indicates individual patient; colored bars represent mutations of genes in that row. Rafael Bejar et al. JCO 2014;32:2691-2698 ©2014 by American Society of Clinical Oncology

MDS-002: Lenalidomide Versus Placebo in RBC-Transfusion Dependent Patients with IPSS Low/Intermediate (Int-1)-Risk MDS without Del(5q) and Unresponsive or Refractory to Erythropoiesis-Stimulating Agents (ESAs) * Discontinuation rate=31.9% in Len arm versus 11% with placebo

Targeting Smad signaling to alleviate anemia in low risk MDS ACE-536 binds to ligands in the TGF-ß superfamily, inhibits Smad 2/3 signaling, and promotes late-stage erythroid differentiation 6/7 low transfusion burden patients achieved RBC transfusion independence (RBC-TI) for ≥8 weeks during the study. 6/19 high transfusion burden patients had a ≥4 unit or ≥50% reduction in RBC units transfused over an 8-week  five of these 6 patients achieved RBC-TI ≥ 8 weeks during the study (range 71-152 days) Platzbecker et al. ASH 2014. Abstract # 411.

Combination studies with hypomethylating agents-SWOG1117 SWOG1117 failed to show benefit of combination strategy with vorinostat or lenalidomide Sekeres et al. ASH 2014. Late Breaking Abstract #5

Patients with failure of hypomethylating agents are challenging due to poor outcomes Survival analysis according to the salvage treatment regimens. Overall response rate for each treatment group is presented with the number of patients evaluable for response in each cohort. (*) Univariate analysis (log-rank test) showed significant differences between palliative care and intensive chemotherapy (CT; P = .04), investigational therapy (IT; P < .001), or allogeneic stem-cell transplantation (ASCT; P < .001). (†)There was also a significant difference between intensive CT and IT (P = .05) and intensive CT and ASCT (P = .008). The difference between IT and ASCT reached borderline significance (P = .09). AZA, azacitidine; NA, not applicable; ORR, overall response rate; OS, overall survival. Thomas Prébet et al. JCO 2011;29:3322-3327 ©2011 by American Society of Clinical Oncology

High-risk MDS: Rigosertib (ONTIME trial-phase 3 multicenter) Rigosertib: a novel small molecule inhibitor of PI3-kinase and PLK pathways Improved survival in patients refractory to hypomethylating agents Garcia-Manero et al. ASH 2014. Abstract # 163

Low dose decitabine- a new look at dosing Suanthararajah et al. JCI 2015 Complete remission (CR) (normalization of blood counts) : in 4 of 25 HI in 7 of 25 (overall response rate, 44%) subjects these were highly durable, the median duration of treatment-induced freedom from transfusion was 999 days for platelets; and 695 days for RBCs

A new conundrum-CHIP (clonal hematopoiesis of indeterminate potential) somatic mutations in hematopoietic cells leading to clonal expansion are commonly acquired during human aging  this is associated with an increased risk of subsequent diagnosis of myeloid or lymphoid neoplasia and increased all-cause mortality MDS is defined by cytopenias, dysplastic morphology of blood and marrow cells, and clonal hematopoiesis most individuals who acquire clonal hematopoiesis during aging will never develop MDS Steensma et al. Blood 2015

MyeloPROLIFERATIVE NEOPLASMS

Genomic landscape of MPNs Frequency of JAK2, CALR, and MPL mutations in PV, ET, and MF.JAK2 mutations are found in 97% of patients with PV and in 50%–60% of those with ET and MF. CALR mutations are the next most frequent genetic aberration, affecting 1/3 of patients with ET or MF. MPL mutations are found in 3%–10% of ET or MF patients. JAK2, MPL, and CALR mutations are mutually exclusive in the majority of patients. Ten to fifteen percent of ET and MF cases have no common underlying genetic marker. Jyoti Nangalia, and Tony R. Green Hematology 2014;2014:287-296 ©2014 by American Society of Hematology

CALR-mutant MPN patients are characterized by a gene signature associated with activated JAK2 signaling. CALR-mutant MPN patients are characterized by a gene signature associated with activated JAK2 signaling. (A) Mutational status of JAK2, CALR, and MPL mutational status as well as clinical MPN diagnosis in 290 MPN patients. An individual column represents each patient. (B) GSEA showing enrichment of JAK2 shRNA signature in MPN patients with CALR mutations relative to normal subjects. (C) Heatmap representation of the 433 significantly differentially expressed genes (413 genes upregulated and 20 downregulated; FDR <0.01 and FC >2) in granulocytes from CALR-mutant MPN patients relative to normal subjects (21 MPN patients and 11 normal subjects). A red-blue color scale depicts normalized gene expression levels (red: high; blue: low). (D) GSEA showing significant enrichment of CALR-mutant MPN signature in MPN patients with homozygous JAK2V617F mutations relative to normal subjects. ©2014 by American Society of Hematology Raajit Rampal et al. Blood 2014;123:e123-e133

Survival data of 793 patients with primary myelofibrosis evaluated at presentation and risk stratified Gangat N et al. JCO 2011;29:392-397

Prognostic impact of molecular features Of the 617 subjects studied, 399 (64.7%) carried JAK2 (V617F), 140 (22.7%) had a CALR exon 9 indel, 25 (4.0%) carried an MPL (W515) mutation, and 53 (8.6%) had nonmutated JAK2, CALR, and MPL (so-called triple-negative PMF). Patients with CALR mutation had a lower risk of developing anemia, thrombocytopenia, and marked leukocytosis compared with other subtypes. They also had a lower risk of thrombosis compared with patients carrying JAK2 (V617F) Rumi et al Blood. 2014

Mutation-Enhanced International Prognostic Scoring System : MIPPS Risk factors Risk Score Age>60 years 1.5 Constitutional symptoms 0.5 Hb <10g/dl Platelets <200,000/dl 1.0 Triple negative (JAK2, MPL, CALR) JAK2 or MPL SRSF2 ASXL low (score 0-0.5) Intermediate-1 (score 1-1.5) Intermediate-2 (score 2-3.5) high (score 4 or greater) Vannucchi et al. ASH 2014. Abstract #405

Treatment Options Allogeneic Stem cell transplant is the only curative option for myelofibrosis largest retrospective series (n=289), allogeneic transplantation resulted in long-term relapse-free survival (RFS) in 1/3 of patients. (Ballen et al. Biol Blood Marrow Transplant 2010) RIC transplant study, 5-year DFS was estimated at 51%; chronic graft-versus-host disease (cGVHD) occurred in 49% and relapse (29%) (Kroger et al. Blood 2009)

Prospective Trial MPD-RC 101 with FluMel conditioning (RIC) Survival after AHSCT with a FluMel conditioning regimen in MF patients. Cumulative OS (A) and EFS (B) in 32 MF patients who received a transplant from a sibling donor. Median survival has not been reached, because 75% of patients were alive at last follow-up and 71% were without disease progression. Cumulative OS (C) and EFS (D) in 34 MF patients who received a transplant from an unrelated donor. Median OS and EFS in unrelated transplants are shown. ©2014 by American Society of Hematology Rondelli D et al. Blood 2014;124:1183-1191

Challenges and future direction of transplant in MF Hepatotoxicity (Wong. BBMT 2012) moderate/severe hyperbilirubinemia (44% vs 21%, P .02) veno-occlusive disease (36% vs 19%, P .05) Graft Failure prospective study MPD-RC 101: higher rate of primary GF in URD transplantation compared with MSD (25% vs 3%). GVHD Alarmingly high incidence of severe GVHD in URD transplants despite the use of thymoglobulin inflammatory cytokines act as mediators of GVHD

MPD-RC 114 (open) Ruxolitinib x 56 days (+ 4 of tapering) RIC stem cell transplant with Fludarbine/low dose Busulfan/ ATG

Will JAK inhibition be helpful in HSCT? Verstovsek S et al., NEJM 2010; 363:1117 Improve engraftment? Reduce GVHD/rejection?

Phase 3 trial of Ruxolitinib in myelofibrosis Verstovsek S et al. N Engl J Med 2012;366:799-807

Ruxolitinib suppresses inflammatory mileu in myelofibrosis Verstovsek S et al. NEJM 2010 Sep 16;363(12):1117-27.

And improves survival….. Overall Survival. Figure 3 Overall Survival. Kaplan–Meier estimates of overall survival, including 4 months of additional follow-up after the primary analysis, are shown. There were 13 deaths in the ruxolitinib group (8.4%) and 24 deaths in the placebo group (15.6%) during a median follow-up period of 51 weeks. Tick marks indicate censoring times for individual patients. Verstovsek S et al. N Engl J Med 2012;366:799-807

Which begets the question….. ??? =

Case 79 year old Hispanic male was diagnosed with JAK2+ive MF in 2009. He was started on Ruxolitinib for symptomatic splenomegaly in 2011. Did very well on this drug for 2 years. March 2014: presents with anemia, thrombocytopenia and fatigue. Found to have Hb=6, plts=30K. Bone marrow biopsy showed myelofibrosis, no increase in blasts. Normal cytogenetics Now what?

Limitations of JAK2 inhibitor therapy ineffective in reversing abnormalities in peripheral blood or histopathologic abnormalities in the marrow eliminating marker cytogenetic abnormalities Reducing the JAK2V617F allele burden to a significant degree rapid return of splenomegaly and MF-related symptoms after discontinuation of the drug Effects on immune function ruxolitinib inhibits CD4+ T cell activation and differentiation both in vitro and in vivo (Yajnanarayana. Br J Hem 2015)

JAK2 inhibitors in development Proposed algorithm of therapy for MF in 2014. Geyer H L , and Mesa R A Blood 2014;124:3529-3537 ©2014 by American Society of Hematology

Therapeutic efficacy of JAK inhibitors. Geyer H L , and Mesa R A Blood 2014;124:3529-3537 ©2014 by American Society of Hematology

Future Directions Alternative pathways to target PI3/Akt pathway mToR inhibitors Telomerase inhibitors-Imelstat HDAC inhibitors AB0024, a monoclonal antibody inhibiting LOXL2 TGF-βsignaling inhibitor MDM2-p53 inhibitor Aurora kinase inhibitors

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