Optimizing CAR-T cell therapy in adults with B-cell acute lymphoblastic leukemia.

Chimeric antigen receptor T-cell (CAR-T) therapy has demonstrated unprecedented success in the treatment of various hematologic malignancies including relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL). Currently, there are two FDA-approved CD19-directed CAR-T cell products for the treatment of adults with R/R B-ALL. Despite high remission rates following CD19 CAR-T cell therapy in R/R B-ALL, remission durability remains limited in most adult patients, with relapse observed frequently in the absence of additional consolidation therapy. Furthermore, the burden of CAR-T cell toxicity remains significant in adults with R/R B-ALL and further limits the wide utilization of this effective therapy. In this review, we discuss patient and disease factors that are linked to CAR-T cell therapy outcomes in R/R B-ALL and strategies to optimize durability of response to reduce relapse and mitigate toxicity in the adult population. We additionally discuss future approaches being explored to maximize the benefit of CAR-T in adults with B-ALL.

Digital polymerase chain reaction strategies for accurate and precise detection of vector copy number in chimeric antigen receptor T-cell products.

BACKGROUND AIMS: Vector copy number (VCN), an average quantification of transgene copies unique to a chimeric antigen receptor (CAR) T-cell product, is a characteristic that must be reported prior to patient administration, as high VCN increases the risk of insertional mutagenesis. Historically, VCN assessment in CAR T-cell products has been performed via quantitative polymerase chain reaction (qPCR). qPCR is reliable along a broad range of concentrations, but quantification requires use of a standard curve and precision is limited. Digital PCR (dPCR) methods were developed for absolute quantification of target sequences by counting nucleic acid molecules encapsulated in discrete, volumetrically defined partitions. Advantages of dPCR compared with qPCR include simplicity, reproducibility, sensitivity and lack of dependency on a standard curve for definitive quantification. In the present study, the authors describe a dPCR assay developed for analysis of the novel bicistronic CD19 × CD22 CAR T-cell construct. METHODS: The authors compared the performance of the dPCR assay with qPCR on both the QX200 droplet dPCR (ddPCR) system (Bio-Rad Laboratories, Inc, Hercules, CA, USA) and the QIAcuity nanoplate-based dPCR (ndPCR) system (QIAGEN Sciences, Inc, Germantown, MD, USA). The primer-probe assay was validated with qPCR, ndPCR and ddPCR using patient samples from pre-clinical CAR T-cell manufacturing production runs as well as Jurkat cell subclones, which stably express this bicistronic CAR construct. RESULTS: ddPCR confirmed the specificity of this assay to detect only the bicistronic CAR product. Additionally, the authors' assay gave accurate, precise and reproducible CAR T-cell VCN measurements across qPCR, ndPCR and ddPCR modalities. CONCLUSIONS: The authors demonstrate that dPCR strategies can be utilized for absolute quantification of CAR transgenes and VCN measurements, with improved test-retest reliability, and that specific assays can be developed for detection of unique constructs.

Effective Use of Extended Dwell Peripheral Intravenous Catheters in Neonatal Intensive Care Patients.

BACKGROUND: Implementing innovative approaches to vascular access can be challenging in the newborn intensive care unit (NICU). PURPOSE: The purpose of this project was to describe the implementation of extended dwell peripheral intravenous (EPIV) catheters, a vascular access device not widely used in the NICU. The implementation involved (1) designing clinical criteria for EPIV catheter use, (2) education of vascular access NICU nurses, and (3) comparing clinical outcomes between vascular access devices (ie, PIV and EPIV catheters). METHODS: We developed evidence-based clinical criteria guiding the use of vascular access devices. We then developed an educational plan for NICU nurses focused on vascular access. Finally, we collected and compared demographic characteristics and clinical data on catheter type and placement attempts, dwell time, and clinical complications associated with each catheter. RESULTS: EPIV catheters were implemented according to evidence-based criteria by a vascular access NICU nursing team. Fifteen percent of PIV catheter placements required 3 or more attempts compared with just 1% of EPIV catheter placement attempts. EPIV catheters had a longer median dwell time (3.5 vs 1 day) and fewer complications than PIV catheters (P < .001). IMPLICATIONS FOR PRACTICE AND RESEARCH: Implementation of an evidence-based approach to vascular access by a team of NICU nurses may improve clinical outcomes. EPIV catheters may be an appropriate alternative device to PIV catheters due to fewer placement attempts, longer dwell times, and overall fewer complications during use. Future vascular access research in the NICU may include a greater focus on innovative placement strategies, optimal maintenance and infection control, and prevention of complications.

Parental Perceptions of Weight Status in Preterm Compared with Term Infants.

Background Parents of overweight children frequently under-recognize their child's overweight status. We hypothesized that parents of preterm children would be more likely than parents of term children to incorrectly perceive their child's weight. Methods We recruited parents of term and preterm when children were 2 months to 2 years of age. Small for gestational age infants were excluded. We compared parents' perceived weight category with child's actual weight category, based on normative data (underweight, normal weight, or overweight). We based analyses on encounters and adjusted for within-child clustering across repeated measures. Results In the preterm (n = 94) and term (n = 1,263) cohorts, 12 and 13% of children, respectively, were overweight (weight-for-length ≥ 95th percentile). Among parents of overweight children, 91% in the preterm cohort and 90% in the term cohort reported their child as healthy weight. Among healthy weight children (weight-for-length 6th-94th percentile), parents in the preterm cohort were more likely to report their child as underweight compared with parents in the term cohort (24 vs. 7%; p < 0.001). Conclusion Parental perception of weight status was impaired among parents of overweight children regardless of gestational age. However, parents were more likely to perceive their healthy weight child as underweight if their child was preterm.

Glucocorticoid Therapy in Acute Lymphoblastic Leukemia: Navigating Short-Term and Long-Term Effects and Optimal Regimen Selection.

PURPOSE OF REVIEW: Glucocorticoids are a mainstay in acute lymphoblastic leukemia treatment and lack of early response is predictive for overall disease prognosis. Given the vital position of glucocorticoids and well known long and short-term side effects associated with differing glucocorticoids, we aim to highlight the wide breadth of historical and more contemporary data to describe the current landscape of glucocorticoid use in this arena. RECENT FINDINGS: Emerging studies aim to overcome issues such as steroid resistance and to optimize the antileukemic effects of glucocorticoids while aiming to mitigate the risks and side effects associated with their exposure. Glucocorticoids have and likely always will be a fundamental component of acute lymphoblastic leukemia treatment and understanding how to navigate short- and long-term effects and how to optimize regimens is at the heart of continued treatment success.

Consolidation with First and Second Allogeneic Transplants in Adults with Relapsed/Refractory B-ALL Following Response to CD19CAR T Cell Therapy.

CD19-targeted chimeric antigen receptor T cell (CAR-T) therapy has led to unprecedented rates of complete remission (CR) in children and adults with relapsed/refractory (r/r) B-cell acute lymphoblastic leukemia (B-ALL), yet the majority of adults relapse after initial response. One proposed method to extend the durability of remission in adults following response to CAR-T therapy is consolidation with allogeneic hematopoietic cell transplantation (alloHCT). Considering the limited published data for the utility of post CAR-T therapy consolidative alloHCT in r/r B-ALL, especially data related to patients receiving a second alloHCT, we sought to describe outcomes of patients with r/r B-ALL at our institution who received their first or second alloHCT following response to CAR-T therapy. We performed a retrospective analysis of adult patients with r/r B-ALL who responded to either investigational or standard of care (SOC) CD19-targeted CAR-T therapy and underwent consolidation with alloHCT while in CR without interim therapy. We identified 45 patients, of whom 26 (58%) and 19 (42%) received their first and second alloHCT as consolidation post CAR-T therapy, respectively. The median age was 31 years (range: 19-67) and 31 (69%) patients were Hispanic. Ph-like was the most common genetic subtype and comprised over half of cases (53%; n = 24). The median number of prior therapies pre-transplant was 5 (range: 2-7), and disease status at the time of alloHCT was CR1, CR2 or ≥CR3 in 7 (16%), 22 (49%) and 16 (35%) patients, respectively. The median time from CAR-T therapy until alloHCT was 93 (range: 42-262) days. The conditioning regimen was radiation-based myeloablative (MAC) in 22 (49%) patients. With a median follow-up of 2.47 years (range: 0.13-6.93), 2-year overall survival (OS), relapse free survival (RFS), cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) were 57.3% (95% CI: 0.432-0.760), 56.2% (95% CI: 0.562-0.745), 23.3% (95% CI: 0.13-0.42), and 20.4% (95% CI: 0.109-0.384), respectively. Two-year OS (52% vs. 68%, P = .641), RFS (54% vs. 59%, P = .820), CIR (33.5% vs. 8.5%, P = .104), and NRM (12.5% vs. 32.2%, P = .120) were not significantly different between patients who underwent their first vs. second transplant, respectively. In univariate analysis, only Ph-like genotype was associated with inferior RFS (P = .03). AlloHCT post CAR-T response is associated with a relatively low early mortality rate and encouraging survival results in high-risk adults with r/r B-ALL, extending to the second alloHCT for fit and eligible patients.

Emerging and Future Targeted Therapies for Pediatric Acute Myeloid Leukemia: Targeting the Leukemia Stem Cells.

Acute myeloid leukemia (AML) is a rare subtype of acute leukemia in the pediatric and adolescent population but causes disproportionate morbidity and mortality in this age group. Standard chemotherapeutic regimens for AML have changed very little in the past 3-4 decades, but the addition of targeted agents in recent years has led to improved survival in select subsets of patients as well as a better biological understanding of the disease. Currently, one key paradigm of bench-to-bedside practice in the context of adult AML is the focus on leukemia stem cell (LSC)-targeted therapies. Here, we review current and emerging immunotherapies and other targeted agents that are in clinical use for pediatric AML through the lens of what is known (and not known) about their LSC-targeting capability. Based on a growing understanding of pediatric LSC biology, we also briefly discuss potential future agents on the horizon.

Hypertension in Pediatric Acute Lymphoblastic Leukemia Patients: Prevalence, Impact, and Management Strategies.

Acute lymphoblastic leukemia (ALL) is the most common cancer diagnosed in children under the age of 18. While modern diagnostic technologies, risk-stratification, and therapy intensification have led to outstanding outcomes for many children with ALL, the side effects and consequences of therapy are not to be underestimated. Hypertension is a well-known acute and chronic side effect of treatment for childhood ALL, although limited data are available regarding the prevalence of hypertension in children undergoing treatment for ALL. In this review of hypertension in pediatric ALL patients, we examine the existing data on incidence and prevalence during treatment and in pediatric ALL survivors. We describe independent risk factors for development of hypertension along with treatment-related causes. Long-term consequences and the risk to survivors of pediatric ALL are further defined. While many ALL patients require antihypertensive medications during some portion of their treatment, there are no clear guidelines on treating inpatient hypertension given challenges that exist in recognizing and managing hypertension in this setting and in this population. Here, we propose an algorithmic approach to diagnose and treat pediatric ALL patients with HTN, along with monitoring and continuation versus cessation of antihypertensive therapy as an outpatient.

Effects of acepromazine and trazodone on anesthetic induction dose of propofol and cardiovascular variables in dogs undergoing general anesthesia for orthopedic surgery.

OBJECTIVE To compare the doses of propofol required to induce general anesthesia in dogs premedicated with acepromazine maleate or trazodone hydrochloride and compare the effects of these premedicants on cardiovascular variables in dogs anesthetized for orthopedic surgery. DESIGN Prospective, randomized study. ANIMALS 30 systemically healthy client-owned dogs. PROCEDURES 15 dogs received acepromazine (0.01 to 0.03 mg/kg [0.005 to 0.014 mg/lb], IM) 30 minutes before anesthetic induction and 15 received trazodone (5 mg/kg [2.27 mg/lb] for patients > 10 kg or 7 mg/kg [3.18 mg/lb] for patients ≤ 10 kg, PO) 2 hours before induction. Both groups received morphine sulfate (1 mg/kg [0.45 mg/lb], IM) 30 minutes before induction. Anesthesia was induced with propofol (4 to 6 mg/kg [1.82 to 2.73 mg/lb], IV, to effect) and maintained with isoflurane or sevoflurane in oxygen. Bupivacaine (0.5 mg/kg [0.227 mg/lb]) and morphine (0.1 mg/kg [0.045 mg/lb]) were administered epidurally. Dogs underwent tibial plateau leveling osteotomy (n = 22) or tibial tuberosity advancement (8) and were monitored throughout anesthesia. Propofol induction doses and cardiovascular variables (heart rate and systemic, mean, and diastolic arterial blood pressures) were compared between groups. RESULTS The mean dose of propofol required for anesthetic induction and all cardiovascular variables evaluated did not differ between groups. Intraoperative hypotension developed in 6 and 5 dogs of the acepromazine and trazodone groups, respectively; bradycardia requiring intervention developed in 3 dogs/group. One dog that received trazodone had priapism 24 hours later and was treated successfully. No other adverse effects were reported. CONCLUSIONS AND CLINICAL RELEVANCE At the described dosages, cardiovascular effects of trazodone were similar to those of acepromazine in healthy dogs undergoing anesthesia for orthopedic surgery.

A quality improvement project to improve the rate of early breast milk expression in mothers of preterm infants.

Providing breast milk is challenging for non-nursing mothers of premature infants. Early breast milk expression results in successful and longer lactation in mothers of very low birth weight (VLBW) infants. This quality improvement initiative sought to increase the rate of early milk expression in mothers of VLBW infants and increase the proportion of infants receiving maternal breast milk (MBM) at 28 days of age and at discharge. Phase 1 (n = 45) occurred between April 1, 2012, and August 31, 2012. Phase 2 (n = 58) occurred between September 1, 2012, and February 28, 2013. Pre-phase 2 actions included increased lactation consultant workforce, early lactation consultation, tracking of MBM supply, and physician education. Inborn infants < 1500 grams were eligible. Primary outcomes were the time of first maternal milk expression (TFME) and infant feeding type at 28 days of age and at discharge. The median TFME decreased from 9 (25th, 75th percentile; 6, 16) hours to 6 (5, 11) hours after implementation (P = .06). The proportion of infants receiving exclusive MBM at 28 days and at discharge was 64% and 74%, respectively (P = .40), and the proportion of infants receiving exclusive MBM at discharge increased from 37% to 59% (P = .046). In conclusion, a multidisciplinary initiative aimed at improving the rate of early milk expression was associated with more VLBW infants receiving exclusive MBM at discharge.

Endoplasmic reticulum stress or mutation of an EF-hand Ca(2+)-binding domain directs the FKBP65 rotamase to an ERAD-based proteolysis.

FKBP65 is an endoplasmic reticulum (ER)-localized chaperone and rotamase, with cargo proteins that include tropoelastin and collagen. In humans, mutations in FKBP65 have recently been shown to cause a form of osteogenesis imperfecta (OI), a brittle bone disease resulting from deficient secretion of mature type I collagen. In this work, we describe the rapid proteolysis of FKBP65 in response to ER stress signals that activate the release of ER Ca(2+) stores. A large-scale screen for stress-induced cellular changes revealed FKBP65 proteins to decrease within 6-12 h of stress activation. Inhibiting IP(3)R-mediated ER Ca(2+) release blocked this response. No other ER-localized chaperone and folding mediators assessed in the study displayed this phenomenon, indicating that this rapid proteolysis of folding mediator is distinctive. Imaging and cellular fractionation confirmed the localization of FKBP65 (72 kDa glycoprotein) to the ER of untreated cells, a rapid decrease in protein levels following ER stress, and the corresponding appearance of a 30-kDa fragment in the cytosol. Inhibition of the proteasome during ER stress revealed an accumulation of FKBP65 in the cytosol, consistent with retrotranslocation and a proteasome-based proteolysis. To assess the role of Ca(2+)-binding EF-hand domains in FKBP65 stability, a recombinant FKBP65-GFP construct was engineered to ablate Ca(2+) binding at each of two EF-hand domains. Cells transfected with the wild-type construct displayed ER localization of the FKBP65-GFP protein and a proteasome-dependent proteolysis in response to ER stress. Recombinant FKBP65-GFP carrying a defect in the EF1 Ca(2+)-binding domain displayed diminished protein in the ER when compared to wild-type FKBP65-GFP. Proteasome inhibition restored mutant protein to levels similar to that of the wild-type FKBP65-GFP. A similar mutation in EF2 did not confer FKBP65 proteolysis. This work supports a model in which stress-induced changes in ER Ca(2+) stores induce the rapid proteolysis of FKBP65, a chaperone and folding mediator of collagen and tropoelastin. The destruction of this protein may identify a cellular strategy for replacement of protein folding machinery following ER stress. The implications for stress-induced changes in the handling of aggregate-prone proteins in the ER-Golgi secretory pathway are discussed. This work was supported by grants from the National Institutes of Health (R15GM065139) and the National Science Foundation (DBI-0452587).