California Institute For Regenerative Medicine Research Articles

IKZF3 Overexpression Phenocopies Gain-of-Function Mutation in Chronic Lymphocytic Leukemia

A hotspot mutation within the DNA-binding domain of IKZF3 (IKZF3-L162R) has been identified as a putative driver in chronic lymphocytic leukemia (CLL); however, its functional effects are unknown. We recently confirmed its role as a CLL driver in a B cell-restricted conditional knock-in model. IKZF3 mutation altered mature B cell development and signaling capacity, and induced CLL-like disease in elderly mice (~40% penetrance). Moreover, we found IKZF3-L162R acts as a gain-of-function mutation, altering DNA binding specificity and target selection of IKZF3, and resulting in overexpression of multiple B-cell receptor (BCR) genes. Consistent with the murine data, RNA-sequencing analysis showed that human CLL cells with mut-IKZF3 [n=4] have an enhanced signature of BCR-signaling gene expression compared to WT-IKZF3 [n=6, all IGHV unmutated] (p<0.001), and also exhibited general upregulation of key BCR-signaling regulators. These results confirm the role of IKZF3 as a master regulator of BCR-signaling gene expression, with the mutation contributing to overexpression of these genes. While mutation in IKZF3 has a clear functional impact on a cardinal CLL-associated pathway, such as BCR signaling, we note that this driver occurs only at low frequency in patients (~3%). Because somatic mutation represents but one mechanism by which a driver can alter a cellular pathway, we examined whether aberrant expression of IKZF3 could also yield differences in BCR-signaling gene expression. We have observed expression of the IKZF3 gene to be variably dysregulated amongst CLL patients through re-analysis of transcriptomic data from two independent cohorts of human CLL (DFCI, Landau et al., 2014; ICGC, Ferreira et al., 2014). We thus examined IKZF3 expression and BCR-signaling gene expression, or the 'BCR score' (calculated as the mean expression of 75 BCR signaling-associate genes) in those cohorts (DFCI cohort, n=107; ICGC cohort, n=274). Strikingly, CLL cells with higher IKZF3 expression (defined as greater than median expression) had higher BCR scores than those with lower IKZF3 expression (<median) (p=0.0015 and p<0.0001, respectively). These findings were consistent with the notion that IKZF3 may act as a broad regulator of BCR signaling genes, and that IKZF3 overexpression, like IKZF3 mutation, may provide fitness advantage. In support of this notion, our re-analysis of a gene expression dataset of 107 CLL samples (Herold Leukemia 2011) revealed that higher IKZF3 expression associated with poorer prognosis and worse overall survival (P=0.035). We previously reported that CLL cells with IKZF3 mutation appeared to increase in cancer cell fraction (CCF) with resistance to fludarabine-based chemotherapy (Landau Nature 2015). Instances of increase in mut-IKZF3 CCF upon treatment with the BCR-signaling inhibitor ibrutinib have been reported (Ahn ASH 2019). These studies together suggest an association of IKZF3 mutation with increased cellular survival following either chemotherapy or targeted treatment. To examine whether higher expression of IKZF3 was associated with altered sensitivity to ibrutinib, we performed scRNA-seq analysis (10x Genomics) of two previously treatment-naïve patients undergoing ibrutinib therapy (paired samples, baseline vs. Day 220). We analyzed an average of 11,080 cells per patient (2000 genes/cell). Of note, following ibrutinib treatment, remaining CLL cells expressed higher levels of IKZF3 transcript compared to pretreatment baseline (both p<0.0001), whereas no such change was observed in matched T cells (n ranging between 62 to 652 per experimental group, p>0.05), suggesting that cells with high expression of IKZF3 were selected by ibrutinib treatment. Moreover, we showed that ibrutinib treatment resulted in consistent upregulation of BCR-signaling genes (e.g., CD79B, LYN, GRB2, FOS, RAC1, PRKCB and NFKBIA) (n ranging between 362 to 1374 per experimental group, all p<0.0001), which were likewise activated by mutant IKZF3. Altogether, these data imply that IKZF3 mutation or overexpression may influence upregulation of BCR-signaling genes and enhance cellular fitness even during treatment with BCR-signaling inhibitors. We highlight our observation that IKZF3 mutation appears to be phenocopied by elevated IKZF3 expression, and suggest that alterations in mRNA or protein level that mimic genetic mutations could be widespread in human cancers. Disclosures Kipps: Pharmacyclics/ AbbVie, Breast Cancer Research Foundation, MD Anderson Cancer Center, Oncternal Therapeutics, Inc., Specialized Center of Research (SCOR) - The Leukemia and Lymphoma Society (LLS), California Institute for Regenerative Medicine (CIRM): Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Honoraria, Research Funding; Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Genentech/Roche: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; VelosBio: Research Funding; Oncternal Therapeutics, Inc.: Other: Cirmtuzumab was developed by Thomas J. Kipps in the Thomas J. Kipps laboratory and licensed by the University of California to Oncternal Therapeutics, Inc., which provided stock options and research funding to the Thomas J. Kipps laboratory, Research Funding; Ascerta/AstraZeneca, Celgene, Genentech/F. Hoffmann-La Roche, Gilead, Janssen, Loxo Oncology, Octernal Therapeutics, Pharmacyclics/AbbVie, TG Therapeutics, VelosBio, and Verastem: Membership on an entity's Board of Directors or advisory committees. Wu:BionTech: Current equity holder in publicly-traded company; Pharmacyclics: Research Funding.

Five-Year Analysis of Murano Study Demonstrates Enduring Undetectable Minimal Residual Disease (uMRD) in a Subset of Relapsed/Refractory Chronic Lymphocytic Leukemia (R/R CLL) Patients (Pts) Following Fixed-Duration Venetoclax-Rituximab (VenR) Therapy (Tx)

Five-Year Analysis of Murano Study Demonstrates Enduring Undetectable Minimal Residual Disease (uMRD) in a Subset of Relapsed/Refractory Chronic Lymphocytic Leukemia (R/R CLL) Patients (Pts) Following Fixed-Duration Venetoclax-Rituximab (VenR) Therapy (Tx)

Genetic Determinants and Evolutionary History of Richter's Syndrome

Genetic Determinants and Evolutionary History of Richter's Syndrome

Expression of Sf3b1-K700E accelerates the Development of Chronic Lymphocytic Leukemia in a Del(13q) Murine Model

Expression of Sf3b1-K700E accelerates the Development of Chronic Lymphocytic Leukemia in a Del(13q) Murine Model

Cirmtuzumab Consolidation for Treatment of Patients with Detectable CLL on Venetoclax

Background: Venetoclax (Ven)-based regimens are highly effective in treating patients with chronic lymphocytic leukemia (CLL), effecting clearance of detectable minimal residual disease (MRD) in many patients after just 1 year of therapy. Approximately, 30% of patients fail to clear detectable MRD within this time period and risk developing, progressive disease (PD) despite continued Ven therapy. Moreover, these patients have a relatively short progression free survival (PFS) after stopping fixed-duration therapy. Therefore, development of consolidation strategies to eradicate detectable MRD and/or to mitigate the risk of PD in patients who fail to clear MRD after 1 year of Ven-based therapy is of vital clinical importance. In particular, patients who fail to clear MRD after 1 year of Ven-based therapy harbor CLL cells with high-level expression of ROR1, an oncoembryonic protein expressed by a broad array of incurable malignancies. Patients who are refractory to MRD-clearance on Ven-based therapies have gene-expression signatures reflective of high-level ROR1-signaling, which can be inhibited by the anti-ROR1 mAb, Cirmtuzumab (Choi et al., Cell Stem Cell. 2018; 22: 951-959). Prior studies demonstrated that Cirmtuzumab and Ven have at least additive activity in promoting cytotoxicity of CLL cells in vitro (Rassenti et al. PNAS. 2017;114(40):10731-10736). As such, cirmtuzumab may be an effective consolidation strategy for patients who fail to clear MRD following completing 1 year of Ven-based therapy. Study Design and Methods: Study Design: We initiated a single center, phase 2 Simon's two-stage-designed study to determine the efficacy of Cirmtuzumab plus Ven combination therapy in patients who fail to clear detectable MRD (defined as > 0.01% of the blood mononuclear cells, as assessed by flow cytometry) after ≥1 year of Ven-based therapy (NCT04501939). Enrolled patients will receive cirmtuzumab at 600 mg IV, q14 days for 2 doses and then monthly thereafter. Patients will continue oral Ven at 400mg daily and be monitored for safety and PD. Following 6 months of Cirmtuzumab + Ven, patients will be assessed for MRD in the blood. At the discretion of the treating physician, patients may continue combination treatment for up to one year (Figure 1). Major Eligibility Criteria: Patients must have a diagnosis of CLL with detectable MRD after having received ≥ 12 months of Ven-based treatment . Patients will be excluded from the study if they have an uncontrolled medical co-morbidity, which compromises their capacity to complete the study, or if they are receiving treatment for CLL with agents other than Ven. End Points: The primary end-point of the proposed study is clearance of detectable MRD in the blood after 6 months of cirmtuzumab + Ven therapy. Secondary end-points include safety and time to next CLL treatment. Exploratory end-points include changes in gene expression in leukemia cells, including analysis of archival pre-Ven treatment samples, when available. Statistical Methods: We used a Simon's two-stage minimax design at 5% significance level to test the scientific hypothesis that 6 cycles of cirmtuzumab + Ven will achieve undetectable MRD (a 'response') in more than 5% of patients, against the null hypothesis of less than a 5% response rate. In the first stage, we plan to accrue 12 patients. If none of these patients respond at 6 months, the study will close. Otherwise, we will accrue an additional 4 patients for a total of 16 patients. If three or more patients respond, the primary endpoint of the trial will have been met, demonstrating an MRD clearance rate greater than 5%. The trial is designed to have 80% power to provide such evidence at the 5% significance level if the true rate of clearance of MRD is 25% or greater. Disclosures Heyman: Oncternal Therapeutics, INC: Research Funding. Choi:Pharmacyclics/Abbvie: Research Funding; Genentech: Consultancy. Jamieson:Forty Seven Inc: Patents & Royalties; Bristol-Myers Squibb: Other. Kipps:Genentech/Roche: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; VelosBio: Research Funding; Oncternal Therapeutics, Inc.: Other: Cirmtuzumab was developed by Thomas J. Kipps in the Thomas J. Kipps laboratory and licensed by the University of California to Oncternal Therapeutics, Inc., which provided stock options and research funding to the Thomas J. Kipps laboratory, Research Funding; Celgene: Honoraria, Research Funding; Ascerta/AstraZeneca, Celgene, Genentech/F. Hoffmann-La Roche, Gilead, Janssen, Loxo Oncology, Octernal Therapeutics, Pharmacyclics/AbbVie, TG Therapeutics, VelosBio, and Verastem: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pharmacyclics/ AbbVie, Breast Cancer Research Foundation, MD Anderson Cancer Center, Oncternal Therapeutics, Inc., Specialized Center of Research (SCOR) - The Leukemia and Lymphoma Society (LLS), California Institute for Regenerative Medicine (CIRM): Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau.

The CLL-1100 Project: Towards Complete Genomic Characterization and Improved Prognostics for CLL

The CLL-1100 Project: Towards Complete Genomic Characterization and Improved Prognostics for CLL

Results of a Phase 1 Open Label Dose Escalation Trial of AB-205 (Allogeneic Engineered Endothelial Cell Therapy) in Adults with Lymphoma Undergoing High-Dose Therapy and Autologous Hematopoietic Cell Transplantation (HDT-AHCT)

Results of a Phase 1 Open Label Dose Escalation Trial of AB-205 (Allogeneic Engineered Endothelial Cell Therapy) in Adults with Lymphoma Undergoing High-Dose Therapy and Autologous Hematopoietic Cell Transplantation (HDT-AHCT)

Publicly Available hiPSC Lines with Extreme Polygenic Risk Scores for Modeling Schizophrenia

Schizophrenia (SZ) is a common and debilitating psychiatric disorder with limited effective treatment options. Although highly heritable, risk for this polygenic disorder depends on the complex interplay of hundreds of common and rare variants. Translating the growing list of genetic loci significantly associated with disease into medically actionable information remains an important challenge. Thus, establishing platforms with which to validate the impact of risk variants in cell-type-specific and donor-dependent contexts is critical. Towards this, we selected and characterized a collection of 12 human induced pluripotent stem cell (hiPSC) lines derived from control donors with extremely low and high SZ polygenic risk scores (PRS). These hiPSC lines are publicly available at the California Institute for Regenerative Medicine (CIRM). The suitability of these extreme PRS hiPSCs for CRISPR-based isogenic comparisons of neurons and glia was evaluated across 3 independent laboratories, identifying 9 out of 12 meeting our criteria. We report a standardized resource of publicly available hiPSCs on which we hope to perform genome engineering and generate diverse kinds of functional data, with comparisons across studies facilitated by the use of a common set of genetic backgrounds.

Dexamethasone in hospitalised patients with COVID-19: addressing uncertainties

Dexamethasone in hospitalised patients with COVID-19: addressing uncertainties

Abstract 694: PAWI-2 overcomes tumor stemness and drug resistance in pancreatic cancer stem cells

Abstract Today, pancreatic cancer (PC) remains a major health problem in the US and soon will be the second most common cause of mortality due to cancer. However, most of the front-line PC chemotherapies cause serious side effects and a majority of patients with PC are often resistant to clinical therapies. The fact that cancer stem cells (CSCs) become enriched after anti-cancer therapy implicates CSCs as key contributors to tumor dormancy, metastasis, and relapse in PC. Given the important role of human pancreatic cancer stem cells (hPCSCs) in PC, development of a novel treatment strategy that targets hPCSCs or their extrinsic and intrinsic regulators could be of great clinical utility to treat PC. Herein, we used a highly validated hPCSCs model (FGβ3 cells) to test a novel compound (PAWI-2) to target CSCs. In this hPCSC model, integrin αvβ3 expression was shown to be a marker/functional contributor to CSC progression and drug resistance attributed to its ability to trigger anchorage-independent cell survival and tumor metastasis. Specifically, integrin αvβ3 recruits KRAS and RalB to tumor cell plasma membranes to activate NF-κB signaling that triggers dysregulated KRAS-RalB-NF-κB pathways. This was shown to be a pharmacological target to reverse CSC-like properties or re-sensitize drug resistance (e.g., EGFR inhibitors, erlotinib) of established FGβ3 tumors. Compared to parental FG cells, PAWI-2 showed greater potency to inhibit cell viability and self-renewal capacity of FGβ3 cells. PAWI-2 inhibited dysregulated integrin β3-KRAS-RalB-NF-κB signaling independent of KRAS and Ral. This is clinically relevant because >90% of KRAS is activated by mutations in PC and RAS or Ral inhibitors have not proven effective clinically. PAWI-2 targeted downstream of KRAS signaling and was negatively regulated by other feedback mechanisms. This was further shown by genetic knockdown of key regulator and co-treatment of specific inhibitors. PAWI-2 overcomes erlotinib resistance in FGβ3 cells with greater potency than bortezomib. In the proposed mechanism of PAWI-2 action, key regulators link the inhibition of KRAS signaling and cell cycle arrest (G2/M). The great utility and pharmacological potency of PAWI-2 in FGβ3 cells (that possess stem-like properties) compared to FG cells provide a basis for further development. PAWI-2 as an efficient therapeutic to reverse tumor stemness and resensitize CSC tumors to drug inhibition. This work was supported by Inception Award from California Institute for Regenerative Medicine (CIRM) (DISC1-10583; J.R. Cashman) and by funds from the Human BioMolecular Research Institute. Citation Format: Jiongjia Cheng, John Cashman, Jorge Gomez-Galeno. PAWI-2 overcomes tumor stemness and drug resistance in pancreatic cancer stem cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 694.

CIRM tools and technologies: Breaking bottlenecks to the development of stem cell therapies.

The California Institute for Regenerative Medicine (CIRM) has a mission to accelerate stem cell treatments to patients with unmet medical needs. This perspective describes successful examples of work funded by CIRM's New Cell Lines and Tools and Technologies Initiatives, which were developed to address bottlenecks to stem cell research and translation. The tools developed through these programs evolved from more discovery‐oriented technologies, such as disease models, differentiation processes, and assays, to more translation focused tools, including scalable good manufacturing processes, animal models, and tools for clinical cell delivery. These tools are available to the research community and many are facilitating translation of regenerative therapeutics today.

Enabling allogeneic therapies: CIRM-funded strategies for immune tolerance and immune evasion.

A major goal for the field of regenerative medicine is to enable the safe and durable engraftment of allogeneic tissues and organs. In contrast to autologous therapies, allogeneic therapies can be produced for many patients, thus reducing costs and increasing availability. However, the need to overcome strong immune system barriers to engraftment poses a significant biological challenge to widespread adoption of allogeneic therapies. While the use of powerful immunosuppressant drugs has enabled the engraftment of lifesaving organ transplants, these drugs have serious side effects and often the organ is eventually rejected by the recipient immune system. Two conceptually different strategies have emerged to enable durable engraftment of allogeneic therapies in the absence of immune suppression. One strategy is to induce immune tolerance of the transplant, either by creating “mixed chimerism” in the hematopoietic system, or by retraining the immune system using modified thymic epithelial cells. The second strategy is to evade the immune system altogether, either by engineering the donor tissue to be “invisible” to the immune system, or by sequestering the donor tissue in an immune impermeable barrier. We give examples of research funded by the California Institute for Regenerative Medicine (CIRM) in each of these areas, ranging from early discovery‐stage work through clinical trials. The advancements that are being made in this area hold promise that many more patients will be able to benefit from regenerative medicine therapies in the future.

Two cancer stem cell-targeted therapies in clinical trials as viewed from the standpoint of the cancer stem cell model.

A key implication of the cancer stem cell model is that for a cancer therapy to be curative, it is imperative to eliminate the cancer stem cells (CSCs) that drive tumor progression. The California Institute for Regenerative Medicine is supporting two novel approaches that target CSCs, one an antibody‐mediated immunotherapy targeting CD47 and the other an antibody targeting ROR1. This article summarizes the evidence that CSCs are targeted and discusses the results of early clinical trials within the context of the CSC model.

PAWI‐2 Overcomes Tumor Stemness and Drug Resistance in Pancreatic Cancer Stem Cells

Today, pancreatic cancer (PC) remains a major health problem in the US and soon will be the second most common cause of mortality due to cancer. However, most of the front‐line PC chemotherapies cause serious side effects and a majority of patients with PC are often resistant to clinical therapies. The fact that cancer stem cells (CSCs) become enriched after anti‐cancer therapy implicates CSCs as key contributors to tumor dormancy, metastasis, and relapse in PC. Given the important role of human pancreatic cancer stem cells (hPCSCs) in PC, development of a novel treatment strategy that targets hPCSCs or their extrinsic and intrinsic regulators could be of great clinical utility to treat PC. Herein, we used a highly validated hPCSCs model (FGβ3 cells) to test a novel compound (PAWI‐2) to target CSCs. In this hPCSC model, integrin αvβ3 expression was shown to be a marker/functional contributor to CSC progression and drug resistance attributed to its ability to trigger anchorage‐independent cell survival and tumor metastasis. Specifically, integrin αvβ3 recruits KRAS and RalB to tumor cell plasma membranes to activate NF‐κB signaling that triggers dysregulated KRAS‐RalB‐NF‐κB pathways. This was shown to be a pharmacological target to reverse CSC‐like properties or re‐sensitize drug resistance (e.g., EGFR inhibitors, erlotinib) of established FGβ3 tumors. Compared to parental FG cells, PAWI‐2 showed greater potency to inhibit cell viability and self‐renewal capacity of FGβ3 cells. PAWI‐2 inhibited dysregulated integrin β3‐KRAS‐RalB‐NF‐κB signaling independent of KRAS and Ral. This is clinically relevant because >90% of KRAS is activated by mutations in PC and RAS or Ral inhibitors have not proven effective clinically. PAWI‐2 targeted downstream of KRAS signaling and was negatively regulated by other feedback mechanisms. This was further shown by genetic knockdown of key regulator and co‐treatment of specific inhibitors. PAWI‐2 overcomes erlotinib resistance in FGβ3 cells with greater potency than bortezomib. In the proposed mechanism of PAWI‐2 action, key regulators link the inhibition of KRAS signaling and cell cycle arrest (G2/M). The great utility and pharmacological potency of PAWI‐2 in FGβ3 cells (that possess stem‐like properties) compared to FG cells provide a basis for further development. PAWI‐2 as an efficient therapeutic to reverse tumor stemness and resensitize CSC tumors to drug inhibition.Support or Funding InformationThis work was supported by Inception Award from California Institute for Regenerative Medicine (CIRM) (DISC1‐10583; J.R. Cashman) and by funds from the Human BioMolecular Research Institute.

Hippo Signaling Pathway has a critical role in Zika Virus Replication and in the Pathogenesis of Neuroinflammation

Zika virus (ZIKV) is a reemerging human pathogen that causes congenital abnormalities including microcephaly and eye disease. The cell/molecular basis of ZIKV and host interactions inducing ocular and neuronal pathogenesis are unclear. Here we noted that the Hippo/SWH signaling pathway, which controls organ size through progenitor cell proliferation and differentiation, is dysregulated following ZIKV infection. In human fetal retinal pigment epithelial (RPE) cells, there is an early induction of transcriptional co‐activator, YAP, which is later degraded with a corresponding activation of the TBK1‐IRF3 Type I interferon pathway. YAP/TAZ silencing results in reduced ZIKV replication, indicating a direct role of Hippo pathway in regulating ZIKV infection. Using an in vivo Ifnr1−/− knockout mice model, ZIKV infection was found to reduce YAP/TAZ protein levels while increasing pYAP Ser127 in the retina and brain. Hippo pathway is activated in major components of the blood‐brain barrier (BBB), incuding endothelial cells and astrocytes. In addition, our data shows AMPK signaling pathway’s role in regulating YAP/TAZ in ZIKV‐infected cells. Our data demonstrates ZIKV infection initiates a crosstalk among AMPK‐Hippo‐TBK1 pathways, which regulate antiviral and energy stress responses during oculo‐neuronal inflammation.Support or Funding InformationThis work was funded by California Institute for Regenerative Medicine (CIRM) Quest – Discovery Stage Research Projects Grant (DISC2‐10188) to V.A. at the University of California, Los Angeles.

A phase Ib/II study of the anti-CD47 antibody magrolimab with cetuximab in solid tumor and colorectal cancer patients.

114 Background: Magrolimab (M, Hu5F9-G4) is an antibody targeting CD47, a macrophage “don’t eat me” signal that demonstrates preclinical synergy with cetuximab (C) in refractory KRAS wild type (KRASwt) and KRAS mutant (KRASm) colorectal (CRC) tumors. Methods: Phase (Ph) 1 doses of M+C were escalated in solid tumor patients (pts) and Ph 2 efficacy was explored in previously treated KRASwt and KRASm CRC patients. Day 1 priming with 1 mg/kg of M was used to mitigate on-target anemia followed by maintenance doses ranging from 10 to 45 mg/kg in combination with C. Ph 2 pts were treated with 30 or 45 mg/kg of M and 400/250 mg/m2 of C. Results: In 78 treated pts (32 Ph 1 and 46 Ph 2), the median age was 59 years (range 19-82), and median prior therapies was 5 (range 1-14). No maximum tolerated dose was reached. Treatment-related adverse events (TRAEs) of any Grade (G) included dermatitis acneiform 36%, dry skin 33%, fatigue 32%, infusion reactions 31%, headache 30%, diarrhea 23%, nausea 23%, chills 23%, and anemia 22%. There were no fatal TRAEs and 3/78 (4%) discontinued M treatment due to any adverse events. In the combined Ph 1+2 study, 2 of 30 evaluable KRASwt CRC pts had confirmed PRs for 7.0 and 12.5 months (mo), for a 6.7% objective response rate (ORR). Both had prior C treatment. The median progression-free survival (mPFS) and median overall survival (mOS) was 3.6 mo (95%CI 1.8-5.4) and 10.1 mo (95%CI: 6.9-14.4), respectively. In 40 evaluable KRASm pts, there were no responses but 45% had stable disease (SD) and the mPFS and mOS were 1.9 mo (95%CI: 1.8-3.5) and 10.4 mo (95%CI: 5.7-16.4), respectively. In 28 KRASm pts who were TAS102/regorafenib naïve, preliminary mOS was 12.4 mo (95%CI: 5.9-not reached) which is longer than that reported for historical controls. Tumor biopsies showed treatment-related increases in macrophage immune cell infiltrates in SD pts, and baseline T cell infiltration was associated with longer OS. Pharmacokinetic profiles will be presented. Conclusions: M+C is a novel, well-tolerated combination immunotherapeutic treatment regimen. Responses were observed in two previously treated CRC pts and survival is encouraging in KRASm pts. Funded by Forty Seven and California Institute for Regenerative Medicine. Clinical trial information: NCT02953782.

Unleashing the cure: Overcoming persistent obstacles in the translation and expanded use of hematopoietic stem cell-based therapies.

Hematopoietic stem cell transplantation (HSCT) is broadly used for treating and curing hematological cancers and various disorders of the blood and immune system. However, its true therapeutic potential remains vastly constrained by significant scientific and technical hurdles that preclude expansion to new indications and limit the number of patients who could benefit from, gain access to, or financially afford the procedure. To define and overcome these challenges, the California Institute for Regenerative Medicine (CIRM) held multiple workshops related to HSCT and has subsequently invested in a new generation of approaches to address the most compelling needs of the field, including new sources of healthy and immunologically compatible hematopoietic stem cells for transplant; safe and efficient genome modification technologies for correction of inherited genetic defects and other forms of gene therapy; safer and more tractable transplantation procedures such as nongenotoxic conditioning regimens, methods to accelerate immune reconstitution and recovery of immune function, and innovations to minimize the risk of immune rejection; and other life‐threatening complications from transplant. This Perspective serves to highlight these needs through examples from the recent CIRM‐funded and other notable investigations, presents rationale for comprehensive, systematic, and focused strategies to unleash the full potential of HSCT, thereby enabling cures for a greatly expanded number of disorders and making HSCT feasible, accessible, and affordable to all who could benefit.

Enhanced Transduction Lentivector Gene Therapy for Treatment of Older Patients with X-Linked Severe Combined Immunodeficiency

Enhanced Transduction Lentivector Gene Therapy for Treatment of Older Patients with X-Linked Severe Combined Immunodeficiency

Lentiviral Gene Therapy with Low Dose Busulfan for Infants with X-SCID Results in the Development of a Functional Normal Immune System: Interim Results of an Ongoing Phase I/II Clinical Study

Lentiviral Gene Therapy with Low Dose Busulfan for Infants with X-SCID Results in the Development of a Functional Normal Immune System: Interim Results of an Ongoing Phase I/II Clinical Study

Phase 2 Study of the Response and Safety of P-Bcma-101 CAR-T Cells in Patients with Relapsed/Refractory (r/r) Multiple Myeloma (MM) (PRIME)

Phase 2 Study of the Response and Safety of P-Bcma-101 CAR-T Cells in Patients with Relapsed/Refractory (r/r) Multiple Myeloma (MM) (PRIME)