Recent Pivotal Studies Research Articles

Clinical Outcomes of CD19 CAR-T-Cell Therapy with Axi-Cel in Relapsed or Refractory Diffuse Large B-Cell Lymphoma (DLBCL) with and without Prior Autologous Stem Cell Transplant

Introduction Diffuse large B-cell lymphoma (DLBCL) is the most common form of aggressive non-Hodgkins lymphoma, accounting for up to 40% of cases. Long term remission is achieved in 50-60% of the patients with rituximab and anthracycline based treatment, but the remaining patients will have either primary refractory or relapsed disease. Prior to the advent of CAR-T-cell therapy, salvage chemotherapy followed by autologous hematopoietic stem cell transplantation (ASCT) was the standard of care for these cases of relapsed or refractory (r/r) disease. For those who relapse post ASCT, options are limited and outcome was dismal. With the results of recent pivotal studies, CAR-T-cell therapy is now offered in patients who are not ASCT candidates and for those who relapse after ASCT. The phenotype of patients who proceed to CAR-T without ASCT is possibly different than those who are able to achieve a clinical response and then proceed to ASCT. While numerous trials have compared the clinical outcomes of ASCT and CAR-T, few have investigated outcomes of CAR-T in previously transplanted versus transplant naïve patients. Wang et al. demonstrated a potential benefit for sequential ASCT and CAR-T in 14 patients with r/r DLBCL, with a median PFS of 14.82 months. Our study compared the clinical outcomes of previously transplanted and transplant naïve patients with r/r DLBCL who received axi-cel (Yescarta) CD19 CAR-T therapy at our center between 2018-2021. Methods Data was collected on 99 patients who received first axi-cel CAR-T therapy at our center for r/r DLBCL between 2018-2021. Of these patients, 84 were transplant naïve and 15 had received prior ASCT. We examined the rate of relapse/progression after CAR-T. Overall survival (OS) was defined as time from date of CD19 CAR-T therapy to death, censored at last known alive. Progression-free survival (PFS) was defined as time from date of CD19 CAR-T therapy to time of disease recurrence or death from any cause, censored at last known alive. Non-relapsed mortality (NRM) was defined as death without relapse or progression. Results 63 patients (64%) were alive as of end of study date. Median follow-up time was 1.70 years (95% CI: 1.54-2.07) for all patients, 1.63 years (95% CI: 1.50-1.99) for transplant naïve patients, and 2.21 (95% CI: 1.09-not reached) for previously transplanted patients. 90-day disease response to CAR-T (CR, PR, SD and PD) was not different for transplant naïve vs. previously transplanted patients (P=0.444). Median OS was not reached for either transplant naïve or previously transplanted patients, with 2-year OS rates of 60% (95% CI: 50-73%) vs. 66% (95% CI: 43-100%) for previously transplanted patients (P=0.23). Median PFS was 0.51 years for transplant naïve patients and not reached for previously transplanted patients, with 2-year PFS rates of 44% (95% CI: 34-56%) for transplant naïve and 56% (95% CI: 33-92%) for previously transplanted patients (P=0.16). 2-year cumulative incidence of relapse or progression was 43% (95% CI: 33-54%) for transplant naïve and 33% (95% CI: 8-58%) for previously transplanted patients (P=0.43). 2-year NRM was 12% (95% CI: 5-20%) for transplant naïve and 11% (95% CI: 0-33%) for previously transplanted patients (P=0.44). In multivariate analysis, bridging therapy, elevated LDH >600 at the time of lymphodepleting chemo, and grade 3 and 4 CRS were associated with worse OS; platelets <75,000 at the time of lymphodepleting chemo, grade 3 and 4 CRS and elevated LDH >600 were associated with worse PFS. There was no difference in the incidence of high grade CRS and neurotoxicity, ICU transfer rate, cytopenias and length of hospitalization between the 2 groups. Conclusions This study showed no significantly significant differences in the OS, PFS, relapse/progression and NRM of r/r DLBCL patients who received CD19 CAR-T-cell therapy (axi-cel) with or without prior ASCT. Other factors such as bridging therapy, elevated LDH and high grade CRS were associated with worse OS. We conclude that prior ASCT does not appear to adversely affect the outcomes of CAR-T-cell therapy. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Fluid biomarkers in stroke: From animal models to clinical care

Stroke is a leading cause of death and disability worldwide. Stroke prevention, early diagnosis, and efficient acute treatment are priorities to successfully impact stroke death and disability. Fluid biomarkers may improve stroke differential diagnostic, patient stratification for acute treatment, and post-stroke individualized rehabilitation. In the present work, we characterized the use of stroke animal models in fluid biomarker research through a systematic review of PubMed and Scopus databases, followed by a literature review on the translation to the human stroke care setting and future perspectives in the field. We found increasing numbers of publications but with limited translation to the clinic. Animal studies are very heterogeneous, do not account for several human features present in stroke, and, importantly, only a minority of such studies used human cohorts to validate biomarker findings. Clinical studies have found appealing candidates, both protein and circulating nucleic acids, to contribute to a more personalized stroke care pathway. Still, brain tissue complexity and the fact that different brain pathologies share lesion biomarkers make this task challenging due to biomarker low specificity. Moreover, the study design and lack of validation cohorts may have precluded a formal integration of biomarkers in different steps of stroke diagnosis and treatment. To overcome such issues, recent pivotal studies on biomarker dynamics in individual patients are providing added value to diagnosis and anticipating patients' early prognosis. Presently, the most consistent protein biomarkers for stroke diagnosis and short- and long-term prognosis are associated with tissue damage at neuronal (TAU), axonal (NFL), or astroglial (GFAP and S100β) levels. Most promising nucleic acids are microRNAs (miR), due to their stability in plasma and ease of access. Still, clinical validation and standardized quantitation place them a step behind compared protein as stroke biomarkers. Ultimately, the definition of clinically relevant biomarker panels and optimization of fast and sensitive biomarker measurements in the blood, together with their combination with clinical and neuroimaging data, will pave the way toward personalized stroke care.

Advances in the Study of Olfaction in Eusocial Ants.

Simple SummaryIn contrast to solitary insects such as the fruit fly or mosquito, eusocial ants form colonial societies comprised of reproductives (female queens and short-lived males) and thousands of sterile female offspring known as workers. Social behaviors such as nursing the queen’s offspring, foraging for food, and nest defense emerge from the collective behavior of the workers. Importantly, these behaviors critically depend on the exchange of information through the detection of chemical cues in the environment. While research efforts have historically aimed to understand the chemical ecology of these social insects, advances in the application of molecular technology over the past decade have facilitated novel studies that bridge the gap between social behaviors and olfaction. Here, we review major advances in the study of molecular olfaction in eusocial ants and highlight potential avenues for future research.Over the past decade, spurred in part by the sequencing of the first ant genomes, there have been major advances in the field of olfactory myrmecology. With the discovery of a significant expansion of the odorant receptor gene family, considerable efforts have been directed toward understanding the olfactory basis of complex social behaviors in ant colonies. Here, we review recent pivotal studies that have begun to reveal insights into the development of the olfactory system as well as how olfactory stimuli are peripherally and centrally encoded. Despite significant biological and technical impediments, substantial progress has been achieved in the application of gene editing and other molecular techniques that notably distinguish the complex olfactory system of ants from other well-studied insect model systems, such as the fruit fly. In doing so, we hope to draw attention not only to these studies but also to critical knowledge gaps that will serve as a compass for future research endeavors.

When the liver gets stiff, the tough get moving.

Liver stiffness measurement (LSM) by FibroScan-determined transient elastography is a noninvasive approach to estimate liver fibrosis severity. In non-alcoholic fatty liver disease (NAFLD), advanced liver fibrosis is excluded by normal liver stiffness, but a wide range of cutoffs have been used to predict advanced liver fibrosis or cirrhosis. This may be partly because steatosis (measured by controlled attenuation parameter [CAP]) contributes to liver stiffness and also because LSM fluctuates in NAFLD. In a recent pivotal study, one-third of patients with liver stiffness >12.0kPa showed reversal after 4-6months; these cases did not have advanced liver fibrosis on biopsy. We performed serial FibroScans 6-36months apart in 73 NAFLD patients, 38 with LSM>10kPa at entry. Those who lost ≥1kg of weight (n=31) significantly reduced liver stiffness (3.6±6.1 vs 0.53±4.1kPa, P<0.05) and CAP score (39±63dB/m of loss vs 24±65dB/m of gain, P<0.05) compared with those who did not (n=29). Patients who reported increased physical activity (n=25) also reduced liver stiffness (3.6±6 vs 0.35±6kPa) and CAP (20±71dB/m of loss vs 32±71dB/m of gain). Overall, those with improved LSM were significantly more likely to have lost weight and/or improved physical activity. These effects of lifestyle adjustments partly explain why a single measurement of 12.0kPa is not a reliable cutoff for advanced liver fibrosis in NAFLD. In addition to repeating the study after 6-12months, documentation of response to lifestyle advice and weight reduction should be determined before assuming any cutoff indicates advanced liver fibrosis. Despite this reservation about diagnostic accuracy, we consider that measurement of liver stiffness and CAP score serve to motivate patients to enact lifestyle modifications that can improve NAFLD severity.

123. Helper-Dependent Ad5/35 Vectors for ZFN Mediated Gene Editing in Hematopoietic Stem Cells

A homozygous [Delta]32 deletion in the CCR5 gene, found in about 1% of Caucasians, confers a natural resistance to HIV-1. In a recent pivotal study it was shown that transplantation of hematopoietic stem/progenitor cells (HSCs) from a donor who was homozygous for CCR5 [Delta]32 in a patient with acute myeloid leukemia and HIV-1 infection resulted in long-term control of HIV. This finding supports the development of gene therapy approaches to eliminate CCR5 in HIV target cells, including approaches based on CCR5-knockout by zinc finger nucleases (ZFNs). Recent trials involved the ex vivo transduction of patient CD4+ T-cells with a CCR5-ZFN expressing adenovirus Ad5/35 vectors. More recent attempts have focused on CCR5 gene knock-out in hematopoietic stem cells (HSCs). Because HSCs are the source for all blood cell lineages, CCR5 knock-out would protect not only CD4 cells but also all remaining lymphoid and myeloid cell types that are potential targets for HIV infection. We generated a helper-dependent, capsid-modified HD-Ad5/35 vector for CCR5-ZFN expression in HSCs from mobilized adult donors. The production of these vectors required that ZFN expression in HD-Ad5/35 producer 293-Cre cells was suppressed. To do this, we developed a miRNA-based system for regulation of gene expression based on miRNA expression profiling of 293-Cre and CD34+ cells.We demonstrated that, after in vitro CD34+ cell transduction, the HD-Ad5/35.ZFNmiR vector conferred ccr5 knock-out in primitive HSC (i.e. long-term culture initiating cells and NOD/SCID repopulating cells). Upon transplantation of in vitro transduced CD34+ cells into irradiated NOG mice, the ccr5 gene disruption frequency achieved in engrafted HSCs found in the bone marrow was about 12%. However, we also found in transplantation studies that the HD-Ad5/35.ZFNmiR vector decreased CD34+ engraftment rates 7-10-fold compared to HD-Ad5/35-GFP (control) transduced cells. A possible interpretation of these data is that sustained high-level ZFN expression afforded by the HD-Ad5/35 vector platform might be detrimental to the HSC, particularly if the cells do not actively divide allowing the extended persistence of HD-Ad5/35 vector genome. This deficit has not been observed with previous first generation recombinant adenoviral vector delivery of ZFNs to CD34+ HSCs (Li et al. Mol Ther 2013), thus the source of the engraftment inhibition is unclear. However, we plan to investigate and develop methods for maximal ccr5 knock-out efficiency in HCSs for future HIV challenge experiments.

Targeting the genetic alterations of the PI3K-AKT-mTOR pathway: its potential use in the treatment of bladder cancers.

Urothelial carcinoma of the bladder is the most frequent tumor of the urinary tract and represents the fifth cause of death by cancer worldwide. The current first line chemotherapy is a combination of cisplatin and gemcitabine with median survival not exceeding 15months. Vinflunine is the only drug approved by EMEA as second-line treatment and few progresses have been made for the past 20years to increase the survival of metastatic patients, especially those who are not eligible for cisplatin-based regimen. The recent studies characterizing the genetic background of urothelial cancers of the bladder, revealed chromosomal alterations that are not seen at the same level in other types of cancers. This is especially the case for mutations of genes involved in the PI3K/AKT/mTOR signaling pathway that occupies a major place in the etiology of these tumors. Here, we describe the mutations leading to constitutive activation of the PI3K/AKT/mTOR pathway and discuss the potential use of the different classes of PI3K/AKT/mTOR inhibitors in the treatment of urothelial bladder cancers. Despite the recent pivotal study evidencing specific mutations of TSC1 in bladder cancer patients responding to everolimus and the encouraging results obtained with other derivatives than rapalogs, few clinical trials are ongoing in bladder cancers. Because of the genetic complexity of these tumors, the cross-talks of the PI3K/AKT/mTOR pathway with other pathways, and the small number of eligible patients, it will be of utmost importance to carefully choose the drugs or drug combinations to be further tested in the clinic.

A non-genetic, epigenetic-like mechanism of telomere length inheritance?

A non-genetic, epigenetic-like mechanism of telomere length inheritance?

Diffuse intrinsic pontine glioma: poised for progress

Diffuse intrinsic pontine gliomas (DIPGs) are amongst the most challenging tumors to treat. Surgery is not an option, the effects of radiation therapy are temporary, and no chemotherapeutic agent has demonstrated significant efficacy. Numerous clinical trials of new agents and novel therapeutic approaches have been performed over the course of several decades in efforts to improve the outcome of children with DIPG, yet without success. The diagnosis of DIPG is based on radiographic findings in the setting of a typical clinical presentation, and tissue is not routinely obtained as the standard of care. The paradigm for treating children with these tumors has been based on that for supratentorial high-grade gliomas in adults as the biology of these lesions were presumed to be similar. However, recent pivotal studies demonstrate that DIPGs appear to be their own entity. Simply identifying this fact releases a number of constraints and opens opportunities for biologic investigation of these lesions, setting the stage to move forward in identifying DIPG-specific treatments. This review will summarize the current state of knowledge of DIPG, discuss obstacles to therapy, and summarize results of recent biologic studies.

Protease Activity of the API2–MALT1 Fusion Oncoprotein in MALT Lymphoma Development and Treatment

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is a prototypical cancer that occurs in the setting of chronic inflammation and an important model for understanding how deregulated NF-κB transcriptional activity contributes to malignancy. Most gastric MALT lymphomas require ongoing antigenic stimulation for continued tumor growth, and Stage I disease is usually cured by eradicating the causative microorganism, Helicobacter pylori, with antibiotics. However, in a subset of MALT lymphomas, chromosomal translocations are acquired that render the lymphoma antigen-independent. The recurrent translocation t(11;18)(q21;q21) is associated with failure to respond to antibiotic therapy and increased rate of dissemination. This translocation creates the API2-MALT1 fusion oncoprotein, which comprises the amino terminus of inhibitor of apoptosis 2 (API2 or cIAP2) fused to the carboxy terminus of MALT1. A common characteristic of chromosomal translocations in MALT lymphoma, including t(11;18), is that genes involved in the regulation of the NF-κB transcription factor are targeted by the translocations, and these genetic perturbations thereby result in deregulated, constitutive NF-κB stimulation. In the last decade, great insights into the roles of API2 and MALT1 in NF-κB signaling have been made. For example, recent pivotal studies have uncovered the long sought-after proteolytic activity of MALT1 and have demonstrated its critical involvement in the survival of certain lymphomas. Here, we review the current understanding of the role of MALT1 in normal lymphocyte function and lymphomagenesis. We then highlight our recent work that has revealed an intriguing link between the proteolytic activity of the API2-MALT1 fusion and its ability to influence lymphomagenesis by cleaving a key NF-κB regulatory protein, NF-κB-inducing kinase.

Improving Outcomes in Advanced Malignant Melanoma

Malignant melanoma continues to increase in incidence throughout the developed world. Surgery remains the cornerstone of curative treatment and the use of adjuvant systemic therapy has provoked much debate. Metastatic disease is incurable in most patients. While combination chemotherapy or biochemotherapy may be considered in certain circumstances, it is now clear that single-agent chemotherapy remains the mainstay of treatment for the majority of patients.A number of new agents and novel approaches are under evaluation and show promise. The pro-apoptotic agent oblimersen has shown improved progression-free survival and response rate, although not overall survival, when combined with dacarbazine compared with dacarbazine alone. The BRaf inhibitor sorafenib (BAY 43-9006) has produced encouraging results when administered with chemotherapy and is now being assessed in randomised studies. Thalidomide in combination with chemotherapy is well tolerated and shows a trend towards increased clinical efficacy compared with chemotherapy alone. Other anti-angiogenic drugs, such as bevacizumab, are being investigated in trials. Results with tumour vaccines have been mixed and several large trials are ongoing. This paper discusses recent pivotal studies and promising new agents in systemic therapy for advanced malignant melanoma.