scholarly journals Combination of Selective Inhibitor of Nuclear Export (SINE) Compounds, Selinexor and KPT-8602, with Venetoclax (ABT-199) Displays Enhanced Activity in Leukemia and Large Cell Lymphoma

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 3949-3949 ◽  
Author(s):  
Melissa A. Fischer ◽  
Sharon Friedlander ◽  
Leah Hogdal ◽  
Pia Arrate ◽  
Hua Chang ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Cell Lines ◽  
Combination Treatment ◽  
Nuclear Export ◽  
Research Funding ◽  
Selective Inhibitor ◽  
Employment Equity ◽  
Advisory Committees ◽  
Cytoplasmic Transport ◽  
Equity Ownership

Abstract Introduction: Exportin 1 (XPO1) is a well characterized and essential nucleo-cytoplasmic transport protein in the karyopherin family, and is responsible for the nuclear export of over 200 cargo proteins, including the major tumor suppressor proteins (TSPs) p53, p21, FOXO and the translation regulator elF4E. XPO1 is overexpressed in numerous cancer types including solid and hematological malignancies, often correlating with poor prognosis. Recently, a novel class of Selective Inhibitors of Nuclear Export (SINE) compounds, selinexor (KPT-330) and the second generation KPT-8602, have been developed for the treatment of advanced cancers. We have previously shown that selinexor has marked activity in AML and DLBCL pre-clinical models. The BCL-2 family of anti-apoptotic proteins are deregulated and linked to maintenance and survival in AML and DLBCL. For its translation, the mRNA for BCL-2 is transported from the nucleus to the cytoplasm by forming a complex with XPO1 cargo, elF4E. Other important mRNAs exported from the nucleus via this mechanism include BCL6 and MYC. We hypothesize that SINE compounds inhibit XPO1/elF4E-mediated nuclear-cytoplasmic transport by covalently binding to the XPO1 cargo binding site and that in the absence of protein translation, BCL-2, BCL6 and MYC levels rapidly decline. Venetoclax (VEN; ABT-199) is a potent, selective inhibitor of BCL-2. In vitro, AML cells acquire resistance to VEN over time, often due to up-regulation of another BCL-2 family anti-apoptotic protein, MCL-1. MCL-1 is regulated by the anti-apoptotic transcription factor and XPO1 cargo NF-kB. We have previously shown that SINE compounds significantly decreased MCL-1 levels, presumably via inactivation of NF-kB. The goal of this study was to test whether SINE compounds will synergize with VEN via BCL-2 modulation and whether the combination would diminish MCL-1 mediated resistance to BCL-2 inhibition in DLBCL and AML models, respectively. Methods: BH3 profiling was performed in a sample of cell lines using a cytochrome c release assay to identify anti-apoptotic dependencies. The effects of SINE compounds and VEN as single agents or in combination on cell viability were performed in AML (K-562, MOLM-13, MV-4-11, and U-937) and DLBCL cell lines (SU-DHL-6, DoHH-2 and Toledo). Whole cell protein lysates were extracted 24 hours after treatment for immunoblot analysis. The activity of SINE compounds (5 mg/kg) and VEN (25 mg/kg) as single agents, or in combination were measured in AML (MV-4-11) and DLBCL (DoHH-2 and Toledo) xenografts in NSGS and nude mice, respectively. Tumor growth and survival were measured throughout these animal studies. Tumor tissue was collected at the end of treatment for flow cytometric analysis, western blotting and immunohistochemistry (IHC). Results: By employing BH3 profiling, we identified AML cell lines that were dependent (MV-4-11 and MOLM-13) and not dependent (U-937 and K-562) on MCL-1. Dose response analysis demonstrated that each of the AML cell lines was sensitive to the SINE compounds, while VEN only reduced viability in the MV-4-11 and MOLM-13 cells. Additionally, there was enhanced growth inhibition when the SINE compounds were combined with VEN in the MCL-1 dependent cells. SINE compound treatment synergistically decreased c-MYC protein levels in all 4 AML cell lines with the combination treatment (Figure 1), whereas PARP cleavage was only enhanced with the combination in the MV-4-11 and MOLM-13 cells. Likewise, MCL-1 is reduced in the presence of SINE compound or SINE compound-VEN combinations. In DLBCL xenograft studies (DoHH-2 and Toledo), combination of selinexor with VEN was synergistic for tumor reduction and increased animal survival when compared to either single agent alone. By IHC we observed a concomitant reduction in BCL-2 and BCL-6 and an increase in cleaved caspase 3 in DLBCL tumors after combination treatment. Conclusions: SINE compound-VEN combinations show enhanced antitumor effect, with reduction of oncogenic activity. SINE compounds reduce MCL-1 in VEN-resistant cells. As MCL-1 driven anti-apoptotic machinery is responsible for resistance to inhibition of BCL-2 in DLBCL and AML, SINE compound regulation of MCL-1 may lead to rescue of VEN resistance. SINE compounds and VEN are excellent candidate partners for combination therapies in AML and DLBCL. Disclosures Friedlander: Karyopharm Therapeutics: Employment. Chang:Karyopharm Therapeutics: Employment, Equity Ownership. Kashyap:Karyopharm Therapeutics: Employment, Equity Ownership. Argueta:Karyopharm Therapeutics: Employment, Equity Ownership. Klebanov:Karyopharm Therapeutics: Employment, Equity Ownership. Senapedis:Karyopharm Therapeutics: Employment, Equity Ownership. Baloglu:Karyopharm Therapeutics: Employment, Equity Ownership. Lee:Karyopharm Therapeutics: Employment, Equity Ownership. Shacham:Karyopharm Therapeutics: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Savona:TG Therapeutics: Research Funding; Amgen Inc.: Membership on an entity's Board of Directors or advisory committees; Takeda: Research Funding; Sunesis: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Ariad: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees.

Absence Of Mutation In Cereblon (CRBN) and DNA Damage Binding Protein 1 (DDB1) Genes In Myeloma Cells and Patients and Its Clinical Significance

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3139-3139
Author(s):  
Anjan Thakurta ◽  
Anita K Gandhi ◽  
Michelle Waldman ◽  
Chad C. Bjorklund ◽  
Suzanne Lentzsch ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Cell Lines ◽  
Research Funding ◽  
Heterozygous Mutation ◽  
Employment Equity ◽  
Advisory Committees ◽  
Single Nucleotide ◽  
Truncating Mutation ◽  
Equity Ownership

Abstract Background CRBN, a target of thalidomide and IMiDs® immunomodulatory agents lenalidomide (LEN) and pomalidomide (POM), is a component of the E3 ubiquitin cullin 4 ring ligase (CRL4) complex that also includes DDB1, Roc1, and Cul4. Two CRBN mutations have been reported in multiple myeloma (MM) patients: truncating mutation (Q99) and point mutation (R283K). One copy of the CRBN gene was shown to be deleted in the MM1S and MM1S.R cell lines. No DDB1 mutation has been described previously. Results We investigated the incidence of CRBN and DDB1 mutations by next-generation sequencing in 20 MM cell lines and MM subjects. Of 90 MM patients, 24 were newly diagnosed and 66 were relapsed and refractory of which 36 patients were LEN resistant. Out of the cell lines tested, 1 heterozygous CRBN mutation (D249Y) was found in the LEN-resistant ANBL6R cells, which is located in the putative DDB1 binding domain, and 2 single silent mutations were identified in the KMS-12-BM (rs17027638) and OPM-2 cells. One DDB1 heterozygous mutation (E303D) was identified in ANBL6 cells. In the cohort of patients assessed, no CRBN mutation was detected; however, 5 single nucleotide variations (SNV) were identified. Three of the 5 SNVs were at position 735 (Y245Y) and 1 each at position 219 (H73H) and 939 (C313C), respectively. The first 2 SNVs (rs17027638 and rs1045309) are described but not the last. We found a single SNV (P51P; rs2230356) in DDB1 gene the patient samples. Conclusion Mutations within the coding sequences of CRBN and DDB1 are rare in MM patients and cell lines. Most intrinsically LEN-resistant cells and cell lines made resistant to LEN or POM do not have CRBN or DDB1 mutations, suggesting the potential role of other sources, such as genetic or epigenetic pathways in developing resistance to IMiD drug–based therapy. Disclosures: Thakurta: Celgene: Employment, Equity Ownership. Gandhi:Celgene: Employment, Equity Ownership. Waldman:Celgene: Employment, Equity Ownership. Bjorklund:Celgene: Employment, Equity Ownership. Lentzsch:Celgene: Research Funding. Schey:Celgene: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau; NAPP: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau; BMS: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau. Orlowski:Bristol-Myers Squibb: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Millennium: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Onyx: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Resverlogix: Research Funding; Array: Honoraria, Membership on an entity’s Board of Directors or advisory committees; Genentech: Honoraria, Membership on an entity’s Board of Directors or advisory committees; Merck: Membership on an entity’s Board of Directors or advisory committees. Madan:Covance Genomics Lab: Employment. Ning:Celgene: Employment, Equity Ownership. Mendy:Celgene: Employment, Equity Ownership. Lopez-Girona:Celgene: Employment, Equity Ownership. Schafer:Celgene: Employment, Equity Ownership. Avet-Loiseau:Celgene: Research Funding. Chopra:Celgene: Employment, Equity Ownership.

Novel Inhibitors Of CRM1/XPO1 Nuclear Exporter Exhibit Striking Activity Against AML “primagrafts,” Including AML Leukemia Initiating Cells, While Sparing Normal Hematopoietic Cells

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3932-3932
Author(s):  
Julia Etchin ◽  
Bonnie Thi Le ◽  
Alex Kentsis ◽  
Richard M. Stone ◽  
Dilara McCauley ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Cell Lines ◽  
Nuclear Export ◽  
Hematopoietic Cells ◽  
Complex Karyotype ◽  
Employment Equity ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Nsg Mice ◽  
Equity Ownership

Abstract Current treatments for acute myeloid leukemia (AML) often fail to induce long-term remissions and are also toxic to normal tissues, prompting the need to develop new targeted therapies. One attractive cellular pathway with therapeutic potential is nuclear export, which is mediated in part by nuclear exporter CRM1/XPO1. XPO1 mediates the transport of ∼220 proteins and several mRNAs and is the sole nuclear exporter of the major tumor suppressor and growth regulatory proteins p53, p73, FOXO, IkB/NF-kB, Rb, p21, and NPM. Our findings demonstrate that novel irreversible inhibitors of XPO1, termed Selective Inhibitors of Nuclear Export, or SINE, induce rapid apoptosis in 12 AML and 14 T-ALL cell lines with IC50s of 15-474 nM. In the SINE-sensitive cell lines, BCL2 overexpression suppresses SINE-induced apoptosis, indicating its intrinsic pathway mediation. Oral administration of clinical XPO1 inhibitor, Selinexor (KPT-330), at 15 or 25 mg/kg, induced remarkable growth suppression in MV4-11 human AML cells and MOLT-4 human T-ALL cells engrafted in immunodeficient NSG mice with negligible toxicity to normal mouse hematopoietic cells after 35 days of treatment. Bone marrow biopsies of selinexor - treated mice were remarkable in that they showed normal hematopoietic cell morphology and cellularity after 35 days of treatment. Significant survival benefit was observed in mice treated with selinexor, compared to vehicle-treated mice. Selinexor is now in Phase 1 clinical trial in patients with AML and other hematological malignancies (NCT01607892). Recently, we have established primagraft models of AML, using primary leukemia blasts isolated from AML patients at diagnosis transplanted into immunocompromised NSG mice. We demonstrated that selinexor exhibits striking anti-leukemic activity against different subtypes of primary AML, including AML-M4; FLT3-ITD and complex karyotype subtypes of the disease. To determine whether selinexor targets leukemia-initiating cells (LICs) of primary AML, we re-transplanted serial dilutions of human CD45+ cells isolated from leukemic mice treated with either vehicle or selinexor. The preliminary results of our re-population assays indicate that selinexor greatly diminished LIC frequency in AML-M4; FLT3-ITD AML (∼6 fold) and complex karyotype disease (∼100 fold). These findings demonstrate that selinexor may represent a novel targeted therapy for the treatment of AML, which spares normal hematopoietic stem and progenitor cells. Disclosures: McCauley: Karyopharm Therapeutics Inc.: Employment, Equity Ownership, Patents & Royalties. Kauffman:Karyopharm Therapeutics Inc.: Employment, Equity Ownership, Membership on an entity’s Board of Directors or advisory committees, Patents & Royalties. Shacham:Karyopharm Therapeutics Inc.: Employment, Equity Ownership, Membership on an entity’s Board of Directors or advisory committees, Patents & Royalties.

A Phase 1/2 Study of the Second Generation Selective Inhibitor of Nuclear Export (SINE) Compound, KPT-8602, in Patients with Relapsed Refractory Multiple Myeloma

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4509-4509 ◽  
Author(s):  
R. Frank Cornell ◽  
Adriana C Rossi ◽  
Rachid Baz ◽  
Craig C Hofmeister ◽  
Chaim Shustik ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Board Of Directors ◽  
Nuclear Export ◽  
Research Funding ◽  
Low Dose ◽  
Phase 1 ◽  
Single Agent ◽  
Employment Equity ◽  
Advisory Committees ◽  
Equity Ownership

Abstract Introduction - Inhibition of Exportin 1 (XPO1) is a novel treatment approach for multiple myeloma (MM). XPO1 mediates the nuclear export of cell-cycle regulators and tumor suppressor proteins leading to their functional inactivation. In addition, XPO1 promotes the export and translation of the mRNA of key oncoproteins (e.g. c-MYC, BCL-2, Cyclin D). XPO1 overexpression occurs in solid and hematological malignancies, including MM and is essential for MM cell survival. Selinexor, the first oral SINE compound, has shown promising anti-MM activity in phase 1 studies but has been associated with gastrointestinal and constitutional toxicities including nausea, anorexia and fatigue. KPT-8602 is a second generation oral SINE compound with similar in vitro potency to selinexor, however, has substantially reduced brain penetration compared with selinexor, and demonstrated markedly improved tolerability with minimal anorexia and weight loss in preclinical toxicology studies. In murine models of MM, KPT-8602 can be dosed daily (QDx5) with minimal anorexia and weight loss. We have therefore initiated a phase 1/2 first-in-human clinical trial. Methods - This phase 1/2 clinical trial was designed to evaluate KPT-8602 as a single agent and in combination with low dose dexamethasone (dex) in patients (pts) with relapsed / refractory MM (RRMM). KPT-8602 is dosed orally (QDx5) for a 28-day cycle with a starting dose of 5 mg. Low dose dex (20 mg, twice weekly) is allowed after cycle 1 if at least a minimal response (MR) is not observed. The primary objective is to evaluate the safety and tolerability including dose-limiting toxicity (DLT), determine the maximum tolerated dose (MTD), the recommended Phase 2 dose (RP2D), and evidence for anti-MM activity for KPT-8602 single agent and in combination with dex. The pharmacokinetic (PK) and pharmacodynamic (PDn; XPO1 mRNA) profile of KPT-8602 will also be determined. PDn predictive biomarker analysis and ex vivo drug response assays are underway using tumor cells from bone marrow aspirates before treatment, during and at relapse. These analyses include cell death pathway assays by flow and nuclear/cytoplasmic localization of XPO1, NF-ƙB, IƙBα, IKKα, NRIF and p53 by imaging flow and IHC. Results - As of 01-Aug-2016, 6 pts 2 M/4 F, (median of 6 prior treatment regimens, median age of 71) with RRMM have been enrolled. Common related grade 1/2 adverse events (AEs) include thrombocytopenia (3 pts), nausea (2 pts) and diarrhea (2 pts). Grade 3 AEs include neutropenia (1 pt) and dehydration (1 pt). No grade 4 or 5 AEs have been reported. No DLTs have been observed and the MTD has not been reached. 5 pts were evaluable for responses (1 pt pending evaluation): 1 partial response, 1 minimal response, and 3 stable disease; no pts have progressed on therapy with the longest on for >5 months. The PK properties following oral administration showed that 5 mg of KPT-8602 was rapidly absorbed (mean tmax= 1 hr, mean Cmax= 30.6 ng/mL). The mean AUCinf was calculated to be 141 ng•hr/mL. After tmax, KPT-8602 declined at an estimated mean t½ of 4 hr. At the same dose level, XPO1 mRNA expression was the highest (~2.5 fold) at 8 hr post dose. Conclusions - Oral KPT-8602 is well tolerated in heavily pretreated pts with RRMM. Gastrointestinal and constitutional toxicities observed with twice weekly selinexor have not been observed with 5x/week KPT-8602, including in pts on study for >4 months. PK was predictable and in line with selinexor. These early results show encouraging disease control with pts remaining on therapy. Enrollment is on-going. Disclosures Rossi: Takeda: Speakers Bureau; Janssen: Speakers Bureau; Onyx: Research Funding, Speakers Bureau; Celgene: Consultancy, Speakers Bureau. Baz:Takeda/Millennium: Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Research Funding; Signal Genetics: Research Funding; Bristol-Myers Squibb: Research Funding; Merck: Research Funding; Novartis: Research Funding. Hofmeister:Karyopharm Therapeutics: Research Funding; Arno Therapeutics, Inc.: Research Funding; Signal Genetics, Inc.: Membership on an entity's Board of Directors or advisory committees; Janssen: Pharmaceutical Companies of Johnson & Johnson: Research Funding; Incyte, Corp: Membership on an entity's Board of Directors or advisory committees; Celgene: Research Funding; Takeda Pharmaceutical Company: Research Funding; Teva: Membership on an entity's Board of Directors or advisory committees. Shustik:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Millenium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees. Richter:Amgen: Consultancy, Speakers Bureau; Takeda: Consultancy, Speakers Bureau; Celgene: Consultancy, Speakers Bureau; Jannsen: Speakers Bureau. Chen:Janssen: Honoraria, Research Funding; Takeda: Research Funding; Celgene: Honoraria, Research Funding. Vogl:Takeda: Consultancy, Research Funding; Celgene: Consultancy; GSK: Research Funding; Calithera: Research Funding; Teva: Consultancy; Karyopharm: Consultancy; Acetylon: Research Funding; Constellation: Research Funding. Shacham:Karyopharm Therapeutics: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Baloglu:Karyopharm Therapeutics: Employment, Equity Ownership. Senapedis:Karyopharm Therapeutics: Employment, Equity Ownership. Ellis:Karyopharm Therapeutics: Employment, Equity Ownership. Friedlander:Karyopharm Therapeutics: Employment. Choe-Juliak:Karyopharm Therapeutics: Employment. Sullivan:Karyopharm Therapeutics: Research Funding. Kauffman:Karyopharm Therapeutics Inc: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees.

Effects Of Inhibition Of XPO1/CRM1-Dependent Nuclear Export By Selinexor (KPT-330), Alone and In Combination With Carfilzomib (CFZ), On Apoptosis and Autophagy In Multiple Myeloma (MM)

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 279-279 ◽  
Author(s):  
Shaun Rosebeck ◽  
Malathi Kandarpa ◽  
Mattina M. Alonge ◽  
Jagoda Jasielec ◽  
Dominik Dytfeld ◽  
...  
Keyword(s):  
Cell Death ◽  
Cancer Cells ◽  
Board Of Directors ◽  
Nuclear Export ◽  
Research Funding ◽  
Proteasome Inhibition ◽  
Employment Equity ◽  
Advisory Committees ◽  
Nuclear Retention ◽  
Equity Ownership

Abstract Introduction Exportin 1 (XPO1/CRM1) is the sole transporter of most tumor suppressor proteins (TSP) from the nucleus to the cytoplasm. Small molecule selective inhibitors of nuclear export (SINE) block XPO1-mediated nuclear export, leading to nuclear retention of TSP, inducing cancer cell death and sensitizing cancer cells to other cytotoxic drugs. Although the cytotoxic and apoptotic effects of SINE on different cancer cells have now been established, the mechanism of cell death is still not fully understood. Recently, autophagy emerged as a possible cell death pathway and alternate to the ubiquitin-proteasome pathway (UPP) by which excess and/or dysfunctional proteins and organelles are degraded and recycled. MM cells require basal autophagy for survival and caspase 10 protease activity is required to limit autophagic cell death. The possibility that autophagy may be involved in the mechanism of action of SINE is supported by observations that knockdown of XPO1 can promote autophagy and that cytoplasmic p53 can repress autophagy. In this study, we evaluated the contribution of autophagy to the effects of Selinexor (KPT-330), a SINE currently in two phase I clinical trials, on MM cell cytotoxicity. Because proteasome inhibition can also induce autophagy, we hypothesized that the combination of Selinexor and CFZ, a next generation irreversible proteasome inhibitor approved for treatment of MM, may synergistically augment cytotoxicity in MM cells. Methods Plasma cells (PC) were purified from consented MM patient bone marrow aspirates using EasySep (Stem Cell Technology). PC purity (>80%) was determined by Wright-Giemsa staining of cytospins. Human myeloma cell lines (HMCL) NCI-H929, RPMI-8226, MM1.S and MM1.R were cultured in RPMI1640 with 10% FBS. IC50 values were determined using GraphPad Prism. Drug combination efficacy was determined using CalcuSyn (Biosoft). Combination index (CI) values <1.0 indicate synergy. Transcription factor profiling plate array II was from Signosis (Sunnyvale, CA). Otherwise, our studies used standard cellular and molecular biology techniques. Results Selinexor caused significant cytotoxicity in HMCL (IC50 10-100 nM), induced cell cycle arrest in G1, and promoted apoptotic cell death typified by caspase activation, DNA fragmentation, and Annexin V binding. Importantly, purified PC from newly-diagnosed MM patients were also sensitive to the cytotoxic effects of Selinexor. HMCL treated with KPT-330 also exhibited nuclear retention of p53. To gain insight into more global effects of SINE treatment, we assayed DNA binding activity of approx. 100 different transcription factors. TSP, such as Rb, p53, and EGR-1, exhibited increased activity, whereas proto-oncogenes, including NF-κB, Myc, and Myb, were inactivated in response to KPT-330. Western blot analysis of inactivated targets showed nearly total loss of protein. Unlike XPO1, which is degraded via the UPP upon treatment with SINE, loss of Myc and NF-κB subunits, including RelA, RelB, and p52, could not be reversed by proteasome inhibition. Instead, we found that Selinexor treatment induced markers of autophagy, including LC3B induction and processing, and promoted loss of caspase 10, which is associated with autophagic cell death in MM. Importantly, we have determined that the combination of Selinexor and CFZ results in synergistic cell death (CI 0.2-0.6) characterized by enhanced induction of both apoptosis and autophagy in HMCL. The effects of Selinexor and CFZ were also evaluated in NOD-SCID mice inoculated subcutaneously with NCI-H929 cells. Mice were treated 3 times weekly per oswith Selinexor (5 or 10 mg/kg) alone and in combination with twice-weekly IV-administered CFZ (1.5 or 3 mg/kg). After 16 days of treatment, high doses of either CFZ or Selinexor alone moderately inhibit tumor growth. Treatment with the combination of CFZ and Selinexor at all dose levels was more effective than single agent treatment, and high dose combination treatment completely impaired xenograft tumor growth with good tolerability. Conclusion Our studies are the first to suggest that Selinexor-induced cell death correlates with both apoptosis and autophagy, and that both cell death pathways are enhanced in response to combined treatment with CFZ. Overall, our pre-clinical study provides strong rationale for evaluation of Selinexor in combination with CFZ for the treatment of MM. Disclosures: McCauley: Karyopharm Therapeutics Inc.: Employment, Equity Ownership, Patents & Royalties. Shacham:Karyopharm Therapeutics Inc.: Employment, Equity Ownership, Membership on an entity’s Board of Directors or advisory committees, Patents & Royalties. Kauffman:Karyopharm Therapeutics Inc.: Employment, Equity Ownership, Membership on an entity’s Board of Directors or advisory committees, Patents & Royalties. Jakubowiak:BMS: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau; Janssen-Cilag: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Karyopharm: Research Funding; Millennium: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; Onyx: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau.

Inhibition Of Nuclear Transport Modulator Xpo1/CRM1 For The Treatment Of Acute Myeloid Leukemia (AML)

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 237-237 ◽  
Author(s):  
Michael P. Rettig ◽  
Matthew Holt ◽  
Julie Prior ◽  
Sharon Shacham ◽  
Michael Kauffman ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Board Of Directors ◽  
Cell Lines ◽  
Nuclear Export ◽  
Employment Equity ◽  
Advisory Committees ◽  
Ic50 Values ◽  
Equity Ownership

Abstract Background Exportin 1 (XPO1) also called CRM1, is a widely expressed nuclear export protein, transporting a variety of molecules including tumor suppressor proteins and cell cycle regulators. Targeted inhibition of XPO1 is a new strategy to restore multiple cell death pathways in various malignant diseases. SINEs are novel, orally available, small molecule Selective Inhibitors of Nuclear Export (SINE) that specifically bind to XPO1 and inhibit its function. Methods We used WST-1 cell proliferation assays, flow cytometry, and bioluminescence imaging to evaluate the efficacy of multiple SINEs to induce apoptosis alone and in combination with cytarabine (AraC) or doxorubicin in vitro in chemotherapy sensitive and resistant murine acute promyelocytic leukemia (APL) cells. This murine model of APL was previously generated by knocking in the human PML-RARa cDNA into the 5’ regulatory sequence of the cathepsin G locus (Westervelt et al. Blood, 2003). The abnormal co-expression of the myeloid surface antigen Gr1 and the early hematopoietic markers CD34 and CD117 identify leukemic blasts. These Gr1+CD34+CD117+ APL cells partially retain the ability to terminally differentiate toward mature granulocytes (mimicking more traditional AML models) and can be adoptively transferred to secondary recipients, which develop a rapidly fatal leukemia within 3 weeks after tumor inoculation. To assess the safety and efficacy of SINEs in vivo, we injected cryopreserved APL cells intravenously via the tail vein into unconditioned genetically compatible C57BL/6 recipients and treated leukemic and non-leukemic mice (n=15/cohort) with 15 mg/kg of the oral clinical staged SINE KPT-330 (currently in Phase 1 studies in patients with solid tumors and hematological malignancies) alone or in combination with 200 mg/kg cytarabine every other day for a total of 2 weeks. Peripheral blood was obtained weekly from mice for complete blood counts and flow cytometry to screen for development of APL. Results The first generation SINE, KPT214, inhibited the proliferation of murine APL cell lines in a dose and time dependent manner with IC50 values ranging from of 95 nM to 750 nM. IC50 values decreased 2.4-fold (KPT-185) and 3.5-fold (KPT-249) with subsequent generations of the SINEs. Consistent with the WST-1 results, Annexin V/7-aminoactinomycin D flow cytometry showed a significant increase of APL apoptosis within 6 hours of KPT-249 application. Minimal toxicity against normal murine lymphocytes was observed with SINEs even up to doses of 500 nM. Additional WST-1 assays using AraC-resistant and doxorubicin-resistant APL cell lines demonstrated cell death of both chemotherapy-resistant cell lines at levels comparable to the parental chemosensitive APL cell lines. Combination therapy with low dose KPT-330 and AraC showed additive effects on inhibition of cell proliferation in vitro. This additive effect of KPT-330 and chemotherapy on APL killing was maintained in vivo. As shown in Figure 1, treatment with AraC or KPT-330 alone significantly prolonged the survival of leukemic mice from a median survival of 24 days (APL + vehicle) to 33 days or 39 days, respectively (P < 0.0001). Encouragingly, combination therapy with AraC + KPT-330 further prolonged survival compared to monotherapy (P < 0.0001), with some mice being cured of the disease. Similar in vivo studies with the AraC-resistant and doxorubicin-resistant APL cells are just being initiated. Conclusions Our data suggests that the addition of a CRM1 inhibitor to a chemotherapy regimen offers a promising avenue for treatment of AML. Disclosures: Shacham: Karyopharm Therapeutics Inc.: Employment, Equity Ownership, Membership on an entity’s Board of Directors or advisory committees, Patents & Royalties. Kauffman:Karyopharm Therapeutics Inc.: Employment, Equity Ownership, Membership on an entity’s Board of Directors or advisory committees, Patents & Royalties. McCauley:Karyopharm Therapeutics, Inc: Employment, Equity Ownership.

scholarly journals Deep and Durable Responses with Selinexor, Daratumumab, and Dexamethasome (SDd) in Patients with Multiple Myeloma (MM) Previously Exposed to Proteasome Inhibitors and Immunomodulatory Drugs: Results of Phase 1b Study of SDd

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 599-599 ◽  
Author(s):  
Cristina J Gasparetto ◽  
Suzanne Lentzsch ◽  
Gary J. Schiller ◽  
William Bensinger ◽  
Nizar Bahlis ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Nuclear Export ◽  
Research Funding ◽  
Phase 1 ◽  
Proteasome Inhibitors ◽  
Maximum Tolerated Dose ◽  
Immunomodulatory Drugs ◽  
Employment Equity ◽  
Advisory Committees ◽  
Equity Ownership

Abstract Introduction - Selinexor is a first-in-class Selective Inhibitor of Nuclear Export (SINE) compound that binds and inactivates Exportin 1 (XPO1). Selinexor with low dose dexamethasone (Sd) or in with protesome inhibitors (PIs) or immunomodulatory drugs (IMiDs), has shown anti-MM activity in patients (pts) with relapsed or refractory MM. Daratumumab (Dara), an anti-CD38 mAb, is approved for the treatment of heavily pretreated MM is limited by short PFS and an ORR of ~21% in quad-refractory MM. Selinexor in combiniation with dara have shown preclinical synergistic killing of MM cells. Methods - Pts were eligible if they had received ≥ 3 prior lines of anti-myeloma therapy, including a PI and an IMiD. Selinexor was dose-escalated in 2 concurrent cohorts: once-weekly (QW, at 100 mg) or twice-weekly (BIW, at 60 mg). Dara was 16 mg/kg IV (recommended schedule) and dexamethasone (dex) was 40 mg QW or 20 mg BIW. The objectives were to determine the maximum tolerated dose (MTD), recommended phase 2 dose (RP2D), safety, tolerability and preliminary efficacy of the combination of this SDd combination in pts with PI/IMiD refractory MM Results - As of Jul 20th2018, 25 pts (11 males / 14 females) have been enrolled. Three pts have been enrolled into the 60 mg BIW and 22 pts in the 100 mg QW cohorts. Pts have a median age of 68 years and a median of 3 (range, 2 - 10) prior treatment regimens. Common SDd treatment related adverse events included (all grades, grades 3/4): thrombocytopenia (58%, 42%), leukopenia (54%, 38%), anemia (46%, 29%), nausea (50%, 0%) and fatigue (46%, 8%). Two dose limiting toxicities (DLTs) were reported in the 60 mg BIW cohort: G3 thrombocytopenia and G2 fatigue requiring dose reduction in selinexor to 100 mg QW. In the 100 mg QW escalation cohort, 6 pts enrolled, 5 evaluable, with no DLTs. This cohort was expanded and enrollment is ongoing. A total of 21 pts were evaluable for response. In 19 dara-naïve pts, the ORR was 74% (5 VGPR, 9 PR, 2 MR, 2 SD, 1 PD), including 3 unconfirmed PRs, 1 unconfirmed MR. In the 2 pts with dara refractory MM, there was one PD and one SD. The longest duration of therapy is 13 months. Based on tolerability and efficacy, the RP2D of SDd is selinexor 100 mg, daratumumab 16 mg/kg and dex 40 mg, administered QW. Conclusions - Selinexor 100 mg QW can be combined safely with dara (per approved dosing) and dex. The preliminary ORR of 74% with SDd in patients with PI/IMiD refractory MM who are dara naïve is promising and compares favorably to 21% ORR of Dara and Sd in quad refractory myeloma. This once weekly regimen is well tolerated with no major organ toxicities to date. Data from the full phase 1 dose expansion will be presented. Disclosures Gasparetto: Takeda: Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria, Other: Travel; Janssen: Consultancy, Honoraria, Other: Travel; Celgene: Consultancy, Honoraria, Other: Travel, Research Funding. Schiller:Celator/Jazz Pharmaceuticals: Research Funding; Pharmacyclics: Research Funding. Bensinger:Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; amgen: Speakers Bureau; Takeda: Speakers Bureau. Bahlis:Celgene: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria. White:Amgen, Celgene, Janssen, Takeda: Honoraria. Sebag:Amgen Canada: Membership on an entity's Board of Directors or advisory committees; Takeda Canada: Membership on an entity's Board of Directors or advisory committees; Janssen Inc.: Membership on an entity's Board of Directors or advisory committees; Celgene Canada: Membership on an entity's Board of Directors or advisory committees. Venner:Janssen: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Amgen: Honoraria; Takeda: Honoraria. Leblanc:Janssen Inc.: Membership on an entity's Board of Directors or advisory committees; Amgen Canada: Membership on an entity's Board of Directors or advisory committees; Celgene Canada: Membership on an entity's Board of Directors or advisory committees; Takeda Canada: Membership on an entity's Board of Directors or advisory committees. Chen:Amgen: Honoraria. Shah:Karyopharm Therapeutics: Employment. Jeha:Karyopharm Therapeutics: Employment. Saint-Martin:Karyopharm Therapeutics: Employment. Kauffman:Karyopharm Therapeutics: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Shacham:Karyopharm Therapeutics: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Lipe:Celgene: Consultancy.

scholarly journals Safety and Efficacy of the Combination of Selinexor, Lenalidomide and Dexamethasone (SRd) in Patients with Newly Diagnosed Multiple Myeloma

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3165-3165 ◽  
Author(s):  
Darrell J White ◽  
Suzanne Lentzsch ◽  
Cristina Gasparetto ◽  
Nizar Bahlis ◽  
Christine I Chen ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Board Of Directors ◽  
Nuclear Export ◽  
Research Funding ◽  
Phase 2 ◽  
Newly Diagnosed ◽  
Efficacy And Safety ◽  
Employment Equity ◽  
Advisory Committees ◽  
Equity Ownership

Introduction: The nuclear export protein Exportin 1 (XPO1) is overexpressed in a wide variety of cancers including multiple myeloma. Selinexor is a novel, first-in-class selective inhibitor of nuclear export (SINE), which blocks XPO1, forcing the nuclear retention and activation of tumor suppressor proteins. Selinexor in combination with low dose dexamethasone (Sel-dex) was recently approved based on data from the STORM study, wherein Sel-dex induced an overall response rate (ORR) of 26.2% in patients with penta-exposed, triple-class refractory multiple myeloma. Lenalidomide in combination with dexamethasone has been approved for the treatment of relapsed/refractory multiple myeloma with an ORR of 60-76%. The STOMP study assessed the efficacy and safety of the all oral combination of selinexor, lenalidomide and dexamethasone (SRd) in patients with relapsed/refractory and newly diagnosed multiple myeloma. We previously reported the recommended phase 2 dose (RP2D) of once weekly selinexor 60 mg, lenalidomide 25 mg and dexamethasone achieved an ORR of 92% in patients with RRMM who were lenalidomide naive. Here we evaluated once weekly selinexor in combination with lenalidomide and dexamethasone in patients with newly diagnosed multiple myeloma. Methods: STOMP is a multicenter, open-label study with a dose escalation (phase 1) and expansion (phase 2) to assess the maximum tolerated dose, RP2D, efficacy and safety of SRd in patients with newly diagnosed multiple myeloma. Patients with newly diagnosed multiple myeloma were eligible if they had symptomatic myeloma per the International Myeloma Working Group (IMWG) guidelines with either hypercalcemia, renal failure, anemia, bone lesions (CRAB) criteria or myeloma defining events needing systemic therapy. Enrollment in this arm is ongoing. Results: As of July 01 2019, 8 patients (4 males and 4 females ) with newly diagnosed multiple myeloma were enrolled at the starting dose level of selinexor 60 mg on days 1, 8, 15, and 22; lenalidomide 25 mg daily 1-21and dexamethasone 40 mg weekly on a 28 day cycle. The median age was 74 years (range: 51-86 years). No dose limiting toxicities (DLT) were observed in 5 DLT evaluable patients, 3 patients were not DLT evaluable because 1 patient did not finish cycle 1 due to social reasons and 2 patients missed doses due to serious adverse events (SAEs) unrelated to study drugs.. Common treatment related hematologic AEs (Grades 1/2, ≥3) were neutropenia (0%, 75%), anemia (0%, 25%), and thrombocytopenia (0%, 25%). Common non-hematologic AEs were diarrhea (63%, 0%), nausea (50%, 0%), fatigue (0%, 38%) decreased weight (38%, 0%), constipation (25%, 0%), hypokalemia (25%, 0%), and hypomagnesemia (25%, 0%). Among 7 efficacy evaluable patients, 6 patients achieved a response (ORR of 86%) including 1 complete response, 1 very good partial responses, 4 partial responses (2 unconfirmed), and 1 patient achieved a minimal response. With a median follow-up of 6.1 months, median progression-free survival was not reached. Conclusions: The all oral combination of SRd has promising activity with 6 of 7 efficacy evaluable patients achieving an objective response in patients with newly diagnosed multiple myeloma and no new or unexpected safety signals. Disclosures White: Amgen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria. Lentzsch:Bayer: Consultancy; Janssen: Consultancy; Takeda: Consultancy; BMS: Consultancy; Proclara: Consultancy; Abbvie: Consultancy; Clinical Care Options: Speakers Bureau; Sanofi: Consultancy, Research Funding; Multiple Myeloma Research Foundation: Honoraria; International Myeloma Foundation: Honoraria; Karyopharm: Research Funding; Columbia University: Patents & Royalties: 11-1F4mAb as anti-amyloid strategy; Caelum Biosciences: Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Gasparetto:Celgene: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; Janssen: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; BMS: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed . Bahlis:Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria. Chen:Janssen: Honoraria, Research Funding; Amgen: Honoraria; Celgene: Honoraria, Research Funding. Lipe:Celgene: Consultancy; amgen: Research Funding; amgen: Consultancy. Schiller:Gilead: Research Funding; Incyte: Research Funding; J&J: Research Funding; Jazz Pharmaceuticals: Honoraria, Research Funding; Karyopharm: Research Funding; Novartis: Research Funding; Sangamo Therapeutics: Research Funding; Pfizer Pharmaceuticals: Equity Ownership, Research Funding; Onconova: Research Funding; Agios: Research Funding, Speakers Bureau; Amgen: Other, Research Funding; Astellas: Research Funding; Biomed Valley Discoveries: Research Funding; Bristol Myer Squibb: Research Funding; Celgene: Research Funding, Speakers Bureau; Constellation Pharmaceutical: Research Funding; Daiichi Sankyo: Research Funding; Eli Lilly and Company: Research Funding; FujiFilm: Research Funding; Genzyme: Research Funding. Tuchman:Karyopharm: Honoraria; Prothena: Research Funding; Roche: Research Funding; Alnylam: Honoraria, Research Funding; Amgen: Research Funding; Sanofi: Research Funding; Merck: Research Funding; Celgene: Honoraria, Research Funding, Speakers Bureau. Kotb:Karyopharm: Equity Ownership; Janssen: Honoraria; Merck: Honoraria, Research Funding; Celgene: Honoraria; Amgen: Honoraria; Takeda: Honoraria. Leblanc:Janssen: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees. Sebag:Amgen: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees. Venner:Sanofi: Honoraria; Amgen: Honoraria, Research Funding; Janssen: Honoraria; J&J: Research Funding; Takeda: Honoraria; Celgene: Honoraria. Bensinger:Amgen, Celgene: Other: Personal Fees, Research Funding, Speakers Bureau; Takeda, Janssen: Speakers Bureau; Sanofi, Seattle Genetics, Merck, Karyopharm: Other: Grant. Sheehan:Karyopharm Therapeutics: Employment, Equity Ownership. Chai:Karyopharm Therapeutics: Employment, Equity Ownership. Kai:Karyopharm Therapeutics: Employment, Equity Ownership. Shah:Karyopharm Therapeutics: Employment, Equity Ownership. Shacham:Karyopharm Therapeutics Inc: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties. Kauffman:Karyopharm Therapeutics Inc: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Baljevic:Karyopharm: Other: Internal Review Committee participant; Cardinal Health Specialty Solutions: Consultancy; Takeda Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees.

­Selective Inhibitor of Nuclear Export (SINE), Selinexor (KPT-330), Shows Remarkable Activity Against AML Leukemia-Initiating Cells

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 995-995
Author(s):  
Julia Etchin ◽  
Bonnie Thi Le ◽  
Alex Kentsis ◽  
Marc R Mansour ◽  
Alla Berezovskaya ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Nuclear Export ◽  
Poor Prognosis ◽  
Phase 1 ◽  
Complex Karyotype ◽  
Employment Equity ◽  
Advisory Committees ◽  
Cytoplasmic Transport ◽  
Blast Cells ◽  
Equity Ownership

Abstract Currently available combination chemotherapy for acute myeloid leukemia (AML) often fails to induce long-term remissions, prompting the need to develop novel therapies. The frequent disease relapse that is observed in patients with AML is thought to occur because of the inability of the existing drugs to target the self-renewing leukemia-initiating (LICs) in AML. An attractive new strategy for AML therapy is inhibition of the nuclear export protein exportin 1 (XPO1), also called CRM1. A member of the karyopherin b family, XPO1 mediates nuclear export of proteins that contain leucine-rich nuclear export signals (NES), including protein adaptors that transport RNA molecules. XPO1 regulates nuclear export of ~220 eukaryotic proteins, including the tumor suppressor proteins p53, p73, p21, Rb, FOXO3A, BRCA1, and PP2A, cell cycle regulators, and apoptotic proteins. Indeed, nuclear-cytoplasmic transport by XPO1 is required for the survival of several types of solid tumors and hematologic malignancies. Recently, novel selective small molecule inhibitors of nuclear export (SINE) that inhibit the export function of XPO1 by targeting Cys528 in its NES-binding groove, were developed using an in silico molecular modeling strategy. The orally bioavailable SINE compound, selinexor (KPT-330), is in Phase 1 and 2 studies in patients with adult AML (NCT01607892 and NCT02088541) and in a Phase 1 study for relapsed childhood ALL and AML that was initiated in March, 2014 (NCT02091245). To determine the anti-leukemic activity of selinexor against primary AML blasts and LICs in a clinically relevant setting, we established mouse xenograft models of human leukemia, in which leukemic blast cells from patients with different subtypes of AML were transplanted into immunodeficient NOD-SCID-IL2Rcgnull (NSG) mice. Engrafted mice were treated with selinexor or a vehicle control. Selinexor was highly active against blast cells from two of the three patients with poor-prognosis disease (cytogenetically normal AML with an internal tandem duplication of FLT3 (AML-CN) and complex karyotype AML (AML-CK1 and AML-CK2)) as evidenced by a reduction in leukemic engraftment in primary mice. Importantly, serial dilution transplantation assays indicate that selinexor therapy greatly reduced the frequency of LICs in xenografts derived from all three patients (6 - to 434- fold reduction compared to controls), indicating that this agent not only targets the bulk leukemic cells, but also eliminates LICs. Interestingly, in mice bearing AML grafts derived from one of the patients with complex karyotype, selinexor dramatically decreased LIC frequency despite exhibiting only modest anti-leukemic activity against bulk disease in primary mice. These findings show that selinexor has potent activity against self-renewing LIC in poor-prognosis AML, even when it has only moderate activity against the bulk AML cell population. Moreover, bone marrow biopsies of selinexor-treated mice showed normal hematopoietic cell morphology and cellularity following four weeks of treatment. These findings demonstrate that inhibition of nuclear export with selinexor addresses the primary remaining problem in the therapy of AML, which is to destroy the very critical self-renewing LIC compartment while sparing normal hematopoietic cells. Disclosures Etchin: Leukemia and Lymphoma Society, Alex's Lemonade Stand, Luck2Tuck Foundation, Karyopharm Therapeutics, Inc: Research Funding. McCauley:Karyopharm Therapeutics, Inc: Employment, Equity Ownership. Kauffman:Karyopharm Therapeutics, Inc: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties. Shacham:Karyopharm Therapeutics, Inc: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties.

Proteolytic Targeting Chimeric Molecules (PROTACs) Specific for Bromodomain-Containing Protein (BRD) 4 Are Active Against Pre-Clinical Models of Multiple Myeloma

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 917-917 ◽  
Author(s):  
Xiaohui Zhang ◽  
Jing Lu ◽  
Yimin Qian ◽  
Robert Z. Orlowski
Keyword(s):  
Multiple Myeloma ◽  
Board Of Directors ◽  
Cell Lines ◽  
Research Funding ◽  
Myeloma Cell ◽  
Employment Equity ◽  
Advisory Committees ◽  
Clinical Models ◽  
Equity Ownership ◽  
Rpmi 8226

Abstract Background: BRD4, a bromodomain and extraterminal domain (BET) family member, has an important role in modulating the expression of essential oncogenes such as c-MYC, and is emerged as a promising therapeutic target in diverse cancer types. Pharmacologic BET inhibitors in development such as JQ1 and OTX015 display preclinical anti-myeloma activity, and induce preferential loss of BRD4 bound to super-enhancers leading to transcriptional repression of c-MYC. Another approach to target this pathway is through the use of bi-functional molecules, which incorporate a small molecule BRD4 binding moiety with an E3 ubiquitin ligase recognition motif, such as ARV-825 and dBET1 (Lu et al. Chem Biol. 22:755, 2015, Winter et al. Science 348:1376, 2015). These agents induce Cereblon (CRBN)-dependent BRD4 ubiquitination and then proteasome-mediated degradation, thereby also reducing downstream c-MYC protein levels. Methods: We performed pre-clinical studies in myeloma cell lines and primary samples using ARV-825 and ARV-763, which are PROTACs that target BRD4 to either the CRBN or the Von Hippel-Lindau (VHL) E3 ligases, respectively. Downstream effects were studied using viability and apoptosis assays, cell cycle profiling, and Western blotting, among others. Results: Tetrazolium assays showed that both PROTACs were able to reduce the viability of a panel of myeloma cell lines, including MM1.S, U266, RPMI 8226, ANBL-6, KAS-6/1, and OPM-2 cells, and this occurred with greater potency than was the case for the BRD4 inhibitors JQ1 or OTX015. Median inhibitory concentrations were 5.66-91.98 nM for ARV-825, and 13.22-1522 nM for ARV-763, respectively. This reduction in viability was both time- and concentration-dependent, and was associated with a reduction of cells in the S phase, and an increase in G0/G1 cells, as well as cells with sub-G0/G1 DNA content, suggesting the onset of apoptosis. Programmed cell death was indeed found to be induced based on the appearance of an increase in Annexin V-positive cells by flow cytometry, and in cleaved caspase 8, caspase 9, caspase 3, and poly-ADP-ribose polymerase by Western blotting. The latter was associated with a specific reduction in the expression levels of both BRD4 and c-MYC that did not influence the abundance of other cellular proteins that were not BRD4 targets, and in a reduction in BRD4 and c-MYC mRNA. In contrast, JQ1 and OTX015 exposure resulted in a slight increase in BRD4 protein expression and a lesser decrease of c-MYC protein. Studies of drug combinations showed that, as expected, lenalidomide and pomalidomide were antagonistic to the effects of the CRBN-targeted ARV-825 PROTAC, but these immunomodulatory drugs showed additive or synergistic effects in combination with the VHL-targeted agent ARV-763. Also as expected, bortezomib and carfilzomib reduced the ability of both ARV-825 and ARV-763 to induce BRD4 degradation, but enhanced anti-proliferative and pro-apoptotic effects were seen in a manner that was influenced by the sequence of drug addition. In studies of drug-resistant cell lines, both PROTACs were able to overcome dexamethasone, melphalan, lenalidomide, and bortezomib resistance, but cross-resistance was seen in RPMI 8226/Dox40 cells, suggesting that these compounds are substrates for P-glycoprotein, which is over-expressed in these cells. Finally, we tested BRD4 PROTACs in primary cells isolated from patients with multiple myeloma, and observed rapid loss of viability of these plasma cells. Conclusions: Taken together, our data demonstrate that BRD4 degraders have promising activity against pre-clinical models of multiple myeloma, and support their translation to the clinic for patients with relapsed/refractory disease. Additional combination and mechanistic studies, as well as data from ongoing in vivo studies, will be presented at the meeting. Disclosures Lu: Arvinas, LLC: Employment, Equity Ownership. Qian:Arvinas, LLC: Employment, Equity Ownership. Orlowski:Acetylon: Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Consultancy, Research Funding; Forma Therapeutics: Consultancy; Celgene: Consultancy, Research Funding; Millennium Pharmaceuticals: Consultancy, Research Funding; Array BioPharma: Consultancy, Research Funding; Onyx Pharmaceuticals: Consultancy, Research Funding; Janssen Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Genentech: Consultancy; BioTheryX, Inc.: Membership on an entity's Board of Directors or advisory committees; Spectrum Pharmaceuticals: Research Funding.

scholarly journals Selinexor Plus Pomalidomide and Low Dose Dexamethasone (SPd) in Patients with Relapsed or Refractory Multiple Myeloma

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1993-1993
Author(s):  
Christine I Chen ◽  
Heather J. Sutherland ◽  
Rami Kotb ◽  
Michael Sebag ◽  
Darrell J. White ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Adverse Events ◽  
Board Of Directors ◽  
Nuclear Export ◽  
Research Funding ◽  
Low Dose ◽  
Published Data ◽  
Employment Equity ◽  
Advisory Committees ◽  
Equity Ownership

Abstract Introduction - The nuclear export protein exportin 1 (XPO1) is overexpressed in a wide variety of cancers including multiple myeloma (MM). Selinexor is a first-in-class Selective Inhibitor of Nuclear Export (SINE) compound that binds and inactivates XPO1. Selinexor forces nuclear retention and reactivation of cell cycle regulators such as p53, IkB, and Rb. Pomalidomide/dexamethasone (Pd) is approved in relapsed/refractory MM (RRMM)with an overall response rate (ORR) of 30% and progression-free survival (PFS) rate of <4 months in patients (pts) having received a prior proteasome inhibitor (PI) and IMiD. Strategies to improve the ORR and PFS are needed. In murine MM models, the combination of selinexor with IMiDs shows synergistic anti-MM activity and good tolerability. Methods- Pts with RRMM who received ≥ 2 prior therapies including lenalidomide (len) and a PI were enrolled. Selinexor was evaluated in 2 different dosing schedules of once-weekly (QW, 60 or 80 mg) or twice-weekly (BIW, 60 or 80 mg), with pomalidomide (pom)3 or 4 mg PO daily, and dexamethasone (dex) 20 mg BIW or 40 mg QW. The primary objectives were to determine the maximum tolerated dose (MTD), recommended phase 2 dose (RP2D), safety, and preliminary efficacy of the combination of selinexor, pomalidomide, and low dose dex (SPd) in pts with RRMM. Results- As of July 20th2018, 34 pts (16 male / 18 female) have been enrolled. The median age is 61 years and patients received a median of 4 (range, 2 - 9) prior treatment regimens. Thirty-two patients were IMiD refractory (21 len, 11 pom/len). Six dose limiting toxicities (DLTs) were observed: G3 fatigue (60 mg BIW, pom 4 mg), G3 febrile neutropenia (FN) (60 mg BIW, pom 3 mg), G3 FN and G4 neutropenia (80 mg QW, pom 4), G3 thrombocytopenia (80 mg QW, pom 3 mg) and 4 missed doses in Cycle 1 due to symptomatic hyponatremia (80 mg BIW, pom 4 mg). Enrollment on selinexor 80 mg QW, pom 3 mg is ongoing. Common SPd treatment related adverse events included (all grades, grades 3/4): neutropenia (62%, 56%), thrombocytopenia (59%, 32%), anemia (53%, 29%), anorexia (56%, 0%), fatigue (50%, 9%), nausea (47%, 0% ). Thirty pts were evaluable for response, which is outlined in Table 1. Median PFS is 10.3 months with a median follow up of 9.4 months. Conclusions- Enrollment is ongoing to evaluate once weekly selinexor in combination with Pd , (SPd). This all-oral SPd combination has clinical activity with an ORR 55% in pom-naive pts with heavily pretreated MM compared to previously published data of 30% ORR for Pd alone. Similarly, the PFS on SPd is 10.3 months vs. <4 months for Pd alone. No unexpected adverse events were noted. Phase 1 dose escalation of the combination of SPd is ongoing to define the optimal RP2D. Disclosures Chen: Amgen: Honoraria. Sebag:Janssen Inc.: Membership on an entity's Board of Directors or advisory committees; Amgen Canada: Membership on an entity's Board of Directors or advisory committees; Takeda Canada: Membership on an entity's Board of Directors or advisory committees; Celgene Canada: Membership on an entity's Board of Directors or advisory committees. White:Amgen, Celgene, Janssen, Takeda: Honoraria. Bensinger:Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Speakers Bureau; celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; amgen: Speakers Bureau. Gasparetto:Bristol-Myers Squibb: Consultancy, Honoraria, Other: Travel; Janssen: Consultancy, Honoraria, Other: Travel; Takeda: Honoraria; Celgene: Consultancy, Honoraria, Other: Travel, Research Funding. Leblanc:Amgen Canada: Membership on an entity's Board of Directors or advisory committees; Janssen Inc.: Membership on an entity's Board of Directors or advisory committees; Celgene Canada: Membership on an entity's Board of Directors or advisory committees; Takeda Canada: Membership on an entity's Board of Directors or advisory committees. Venner:Janssen: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Amgen: Honoraria; Takeda: Honoraria. Schiller:Pharmacyclics: Research Funding; Celator/Jazz Pharmaceuticals: Research Funding. Lipe:Celgene: Consultancy. Shah:Karyopharm Therapeutics: Employment. Jeha:Karyopharm Therapeutics: Employment. Saint-Martin:Karyopharm Therapeutics: Employment. Kauffman:Karyopharm Therapeutics: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Shacham:Karyopharm Therapeutics: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Bahlis:Amgen: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding.

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