Microglia regulate central nervous system myelin growth and integrity.

Myelin is required for the function of neuronal axons in the central nervous system, but the mechanisms that support myelin health are unclear. Although macrophages in the central nervous system have been implicated in myelin health1, it is unknown which macrophage populations are involved and which aspects they influence. Here we show that resident microglia are crucial for the maintenance of myelin health in adulthood in both mice and humans. We demonstrate that microglia are dispensable for developmental myelin ensheathment. However, they are required for subsequent regulation of myelin growth and associated cognitive function, and for preservation of myelin integrity by preventing its degeneration. We show that loss of myelin health due to the absence of microglia is associated with the appearance of a myelinating oligodendrocyte state with altered lipid metabolism. Moreover, this mechanism is regulated through disruption of the TGFß1-TGFßR1 axis. Our findings highlight microglia as promising therapeutic targets for conditions in which myelin growth and integrity are dysregulated, such as in ageing and neurodegenerative disease2,3.

Uterine-Artery Embolization or Myomectomy for Uterine Fibroids.

BACKGROUND: Uterine fibroids, the most common type of tumor among women of reproductive age, are associated with heavy menstrual bleeding, abdominal discomfort, subfertility, and a reduced quality of life. For women who wish to preserve their uterus and who have not had a response to medical treatment, myomectomy and uterine-artery embolization are therapeutic options. METHODS: We conducted a multicenter, randomized, open-label trial to evaluate myomectomy, as compared with uterine-artery embolization, in women who had symptomatic uterine fibroids and did not want to undergo hysterectomy. Procedural options included open abdominal, laparoscopic, or hysteroscopic myomectomy. The primary outcome was fibroid-related quality of life, as assessed by the score on the health-related quality-of-life domain of the Uterine Fibroid Symptom and Quality of Life (UFS-QOL) questionnaire (scores range from 0 to 100, with higher scores indicating a better quality of life) at 2 years; adjustment was made for the baseline score. RESULTS: A total of 254 women, recruited at 29 hospitals in the United Kingdom, were randomly assigned: 127 to the myomectomy group (of whom 105 underwent myomectomy) and 127 to the uterine-artery embolization group (of whom 98 underwent embolization). Data on the primary outcome were available for 206 women (81%). In the intention-to-treat analysis, the mean (±SD) score on the health-related quality-of-life domain of the UFS-QOL questionnaire at 2 years was 84.6±21.5 in the myomectomy group and 80.0±22.0 in the uterine-artery embolization group (mean adjusted difference with complete case analysis, 8.0 points; 95% confidence interval [CI], 1.8 to 14.1; P = 0.01; mean adjusted difference with missing responses imputed, 6.5 points; 95% CI, 1.1 to 11.9). Perioperative and postoperative complications from all initial procedures, irrespective of adherence to the assigned procedure, occurred in 29% of the women in the myomectomy group and in 24% of the women in the uterine-artery embolization group. CONCLUSIONS: Among women with symptomatic uterine fibroids, those who underwent myomectomy had a better fibroid-related quality of life at 2 years than those who underwent uterine-artery embolization. (Funded by the National Institute for Health Research Health Technology Assessment program; FEMME Current Controlled Trials number, ISRCTN70772394.).

Central venous access devices for the delivery of systemic anticancer therapy (CAVA): a randomised controlled trial.

BACKGROUND: Hickman-type tunnelled catheters (Hickman), peripherally inserted central catheters (PICCs), and totally implanted ports (PORTs) are used to deliver systemic anticancer treatment (SACT) via a central vein. We aimed to compare complication rates and costs of the three devices to establish acceptability, clinical effectiveness, and cost-effectiveness of the devices for patients receiving SACT. METHODS: We did an open-label, multicentre, randomised controlled trial (Cancer and Venous Access [CAVA]) of three central venous access devices: PICCs versus Hickman (non-inferiority; 10% margin); PORTs versus Hickman (superiority; 15% margin); and PORTs versus PICCs (superiority; 15% margin). Adults (aged ≥18 years) receiving SACT (≥12 weeks) for solid or haematological malignancy from 18 oncology units in the UK were included. Four randomisation options were available: Hickman versus PICCs versus PORTs (2:2:1), PICCs versus Hickman (1:1), PORTs versus Hickman (1:1), and PORTs versus PICCs (1:1). Randomisation was done using a minimisation algorithm stratifying by centre, body-mass index, type of cancer, device history, and treatment mode. The primary outcome was complication rate (composite of infection, venous thrombosis, pulmonary embolus, inability to aspirate blood, mechanical failure, and other) assessed until device removal, withdrawal from study, or 1-year follow-up. This study is registered with ISRCTN, ISRCTN44504648. FINDINGS: Between Nov 8, 2013, and Feb 28, 2018, of 2714 individuals screened for eligibility, 1061 were enrolled and randomly assigned, contributing to the relevant comparison or comparisons (PICC vs Hickman n=424, 212 [50%] on PICC and 212 [50%] on Hickman; PORT vs Hickman n=556, 253 [46%] on PORT and 303 [54%] on Hickman; and PORT vs PICC n=346, 147 [42%] on PORT and 199 [58%] on PICC). Similar complication rates were observed for PICCs (110 [52%] of 212) and Hickman (103 [49%] of 212). Although the observed difference was less than 10%, non-inferiority of PICCs was not confirmed (odds ratio [OR] 1·15 [95% CI 0·78-1·71]) potentially due to inadequate power. PORTs were superior to Hickman with a complication rate of 29% (73 of 253) versus 43% (131 of 303; OR 0·54 [95% CI 0·37-0·77]). PORTs were superior to PICCs with a complication rate of 32% (47 of 147) versus 47% (93 of 199; OR 0·52 [0·33-0·83]). INTERPRETATION: For most patients receiving SACT, PORTs are more effective and safer than both Hickman and PICCs. Our findings suggest that most patients receiving SACT for solid tumours should receive a PORT within the UK National Health Service. FUNDING: UK National Institute for Health Research Health Technology Assessment Programme.

Loss of the heterogeneous expression of flippase ATP11B leads to cerebral small vessel disease in a normotensive rat model.

Cerebral small vessel disease (SVD) is the leading cause of vascular dementia, causes a quarter of strokes, and worsens stroke outcomes. The disease is characterised by patchy cerebral small vessel and white matter pathology, but the underlying mechanisms are poorly understood. This microvascular and tissue damage has been classically considered secondary to extrinsic factors, such as hypertension, but this fails to explain the patchy nature of the disease, the link to endothelial cell (EC) dysfunction even when hypertension is absent, and the increasing evidence of high heritability to SVD-related brain damage. We have previously shown the link between deletion of the phospholipase flippase Atp11b and EC dysfunction in an inbred hypertensive rat model with SVD-like pathology and a single nucleotide polymorphism (SNP) in ATP11B associated with human sporadic SVD. Here, we generated a novel normotensive transgenic rat model, where Atp11b is deleted, and show pathological, imaging and behavioural changes typical of those in human SVD, but that occur without hypertension. Atp11bKO rat brain and retinal small vessels show ECs with molecular and morphological changes of dysfunction, with myelin disruption in a patchy pattern around some but not all brain small vessels, similar to the human brain. We show that ATP11B/ATP11B is heterogeneously expressed in ECs in normal rat and human brain even in the same transverse section of the same blood vessel, suggesting variable effects of the loss of ATP11B on each vessel and an explanation for the patchy nature of the disease. This work highlights a link between inherent EC dysfunction and vulnerability to SVD white matter damage with a marked heterogeneity of ECs in vivo which modulates this response, occurring even in the absence of hypertension. These findings refocus our strategies for therapeutics away from antihypertensive (and vascular risk factor) control alone and towards ECs in the effort to provide alternative targets to prevent a major cause of stroke and dementia.

Identifying and Treating Opioid Side Effects: The Development of Methylnaltrexone.

Methylnaltrexone Reverses Chronic Opioid-induced Constipation: A Randomized, Controlled Trial. By Yuan CS, Foss JF, O'Connor M, Osinski J, Karrison T, Moss J, Roizen MF. JAMA 2000; 130:142-8. Reprinted with permission. CONTEXT: Constipation is the most common chronic adverse effect of opioid pain medications in patients who require long-term opioid administration, such as patients with advanced cancer, but conventional measures for ameliorating constipation often are insufficient. OBJECTIVE: To evaluate the efficacy of methylnaltrexone, the first peripheral opioid receptor antagonist, in treating chronic methadone-induced constipation. DESIGN: Double-blind, randomized, placebo-controlled trial conducted between May 1997 and December 1998. SETTING: Clinical research center of a university hospital. PARTICIPANTS: Twenty-two subjects (9 men and 13 women; mean [SD] age, 43.2 [5.5] years) enrolled in a methadone maintenance program and having methadone-induced constipation. MAIN OUTCOME MEASURES: Laxation response, oral-cecal transit time, and central opioid withdrawal symptoms were compared between the 2 groups. RESULTS: The 11 subjects in the placebo group showed no laxation response, and all 11 subjects in the intervention group had laxation response after intravenous methylnaltrexone administration (P<.001). The oral-cecal transit times at baseline for subjects in the methylnaltrexone and placebo groups averaged 132.3 and 126.8 minutes, respectively. The average (SD) change in the methylnaltrexone-treated group was -77.7 (37.2) minutes, significantly greater than the average change in the placebo group (-1.4 [12.0] minutes; P<.001). No opioid withdrawal was observed in any subject, and no significant adverse effects were reported by the subjects during the study. CONCLUSIONS: Our data demonstrate that intravenous methylnaltrexone can induce laxation and reverse slowing of oral cecal-transit time in subjects taking high opioid dosages. Low-dosage methylnaltrexone may have clinical utility in managing opioid-induced constipation.

Fine processes of Nestin-GFP-positive radial glia-like stem cells in the adult dentate gyrus ensheathe local synapses and vasculature.

Adult hippocampal neurogenesis relies on the activation of neural stem cells in the dentate gyrus, their division, and differentiation of their progeny into mature granule neurons. The complex morphology of radial glia-like (RGL) stem cells suggests that these cells establish numerous contacts with the cellular components of the neurogenic niche that may play a crucial role in the regulation of RGL stem cell activity. However, the morphology of RGL stem cells remains poorly described. Here, we used light microscopy and electron microscopy to examine Nestin-GFP transgenic mice and provide a detailed ultrastructural reconstruction analysis of Nestin-GFP-positive RGL cells of the dentate gyrus. We show that their primary processes follow a tortuous path from the subgranular zone through the granule cell layer and ensheathe local synapses and vasculature in the inner molecular layer. They share the ensheathing of synapses and vasculature with astrocytic processes and adhere to the adjacent processes of astrocytes. This extensive interaction of processes with their local environment could allow them to be uniquely receptive to signals from local neurons, glia, and vasculature, which may regulate their fate.

Tangential migration of neuronal precursors of glutamatergic neurons in the adult mammalian brain.

In a classic model of mammalian brain formation, precursors of principal glutamatergic neurons migrate radially along radial glia fibers whereas GABAergic interneuron precursors migrate tangentially. These migration modes have significant implications for brain function. Here we used clonal lineage tracing of active radial glia-like neural stem cells in the adult mouse dentate gyrus and made the surprising discovery that proliferating neuronal precursors of glutamatergic granule neurons exhibit significant tangential migration along blood vessels, followed by limited radial migration. Genetic birthdating and morphological and molecular analyses pinpointed the neuroblast stage as the main developmental window when tangential migration occurs. We also developed a partial "whole-mount" dentate gyrus preparation and observed a dense plexus of capillaries, with which only neuroblasts, among the entire population of progenitors, are directly associated. Together, these results provide insight into neuronal migration in the adult mammalian nervous system.

Effectiveness of Embolization or Sclerotherapy of Pelvic Veins for Reducing Chronic Pelvic Pain: A Systematic Review.

PURPOSE: Chronic pelvic pain (CPP) in the presence of dilated and refluxing pelvic veins is often described as pelvic congestion syndrome (PCS), although the causal relationship between pelvic vein incompetence and CPP has not been established. Percutaneous embolization is the principal treatment for PCS, with high success rates cited. This study was undertaken to systematically and critically review the effectiveness of embolization of incompetent pelvic veins. MATERIALS AND METHODS: A comprehensive search strategy encompassing various terms for pelvic congestion, pelvic pain, and embolization was deployed in 17 bibliographic databases, with no restriction on study design. Methodologic quality was assessed. The quality and heterogeneity generally precluded meta-analysis. Results were tabulated and described narratively. RESULTS: Twenty-one prospective case series and one poor-quality randomized trial of embolization (involving a total of 1,308 women) were identified. Early substantial relief from pain was observed in approximately 75% of women undergoing embolization, and generally increased over time and was sustained. Significant pain reductions following treatment were observed in all studies that measured pain on a visual analog scale. Repeat intervention rates were generally low. There were few data on the impact on menstruation, ovarian reserve, or fertility, but no concerns were noted. Transient pain was common following foam embolization, and there was a < 2% risk of coil migration. CONCLUSIONS: Embolization appears to provide symptomatic relief of CPP in the majority of women and is safe, although the quality of the evidence is low.

Randomized Clinical Trial of a Sustained-Exposure Ciprofloxacin for Intratympanic Injection During Tympanostomy Tube Surgery.

OBJECTIVE: This exploratory clinical trial evaluated the safety and clinical activity of a novel, sustained-exposure formulation of ciprofloxacin microparticulates in poloxamer (OTO-201) administered during tympanostomy tube placement in children. METHODS: Double-blind, randomized, prospective, placebo- and sham-controlled, multicenter Phase 1b trial in children (6 months to 12 years) with bilateral middle ear effusion requiring tympanostomy tube placement. Patients were randomized to intraoperative OTO-201 (4 mg or 12 mg), placebo, or sham (2:1:1 ratio). RESULTS: Eighty-three patients (52 male/31 female; mean age, 2.80 years) were followed for safety (otoscopic exams, cultures, audiometry, and tympanometry) and clinical activity, defined as treatment failure (physician-documented otorrhea and/or otic or systemic antibiotic use ≥3 days post surgery). At baseline, 14.3% to 36.8% of children showed positive cultures of middle ear effusion samples in at least 1 ear. Through day 15, treatment failures accounted for 14.3%, 15.8%, 45.5%, and 42.9% of patients (OTO-201 4 mg, OTO-201 12 mg, placebo, and sham, respectively); treatment failure reductions for OTO-201 doses were significant compared to pooled control (P values = .023 and .043, respectively). Observed OTO-201 safety profile was indistinguishable from placebo or sham. CONCLUSIONS: Results of this first clinical trial suggest that OTO-201 was well tolerated and shows preliminary clinical activity in treating tympanostomy tube otorrhea.

The mu opioid receptor: A new target for cancer therapy?

Mu opioids are among the most widely used drugs for patients with cancer with both acute and chronic pain as well as in the perioperative period. Several retrospective studies have suggested that opioid use might promote tumor progression and as a result negatively impact survival in patients with advanced cancer; however, in the absence of appropriate prospective validation, any changes in recommendations for opioid use are not warranted. In this review, the authors present preclinical and clinical data that support their hypothesis that the mu opioid receptor is a potential target for cancer therapy because of its plausible role in tumor progression. The authors also propose the hypothesis that peripheral opioid antagonists such as methylnaltrexone, which reverses the peripheral effects of mu opioids but maintains centrally mediated analgesia and is approved by the US Food and Drug Administration for the treatment of opioid-induced constipation, can be used to target the mu opioid receptor.

A circuit-based gatekeeper for adult neural stem cell proliferation: Parvalbumin-expressing interneurons of the dentate gyrus control the activation and proliferation of quiescent adult neural stem cells.

Newborn neurons are generated in the adult hippocampus from a pool of self-renewing stem cells located in the subgranular zone (SGZ) of the dentate gyrus. Their activation, proliferation, and maturation depend on a host of environmental and cellular factors but, until recently, the contribution of local neuronal circuitry to this process was relatively unknown. In their recent publication, Song and colleagues have uncovered a novel circuit-based mechanism by which release of the neurotransmitter, γ-aminobutyric acid (GABA), from parvalbumin-expressing (PV) interneurons, can hold radial glia-like (RGL) stem cells of the adult SGZ in a quiescent state. This tonic GABAergic signal, dependent upon the activation of γ(2) subunit-containing GABA(A) receptors of RGL stem cells, can thus prevent their proliferation and subsequent maturation or return them to quiescence if previously activated. PV interneurons are thus capable of suppressing neurogenesis during periods of high network activity and facilitating neurogenesis when network activity is low.

Can ovarian vein embolization cause more harm than good?

Ovarian vein embolization using embolic coils is a recognized treatment for chronic pelvic pain caused by pelvic congestion syndrome (PCS). Although it is considered a non-invasive procedure with a good safety record, there have been reported complications resulting from embolic coil migration. We present a case of embolic coil erosion of the ovarian vein discovered on laparoscopy for chronic pelvic pain.

A multicenter, randomized, double-blind placebo-controlled, single dose trial of the safety and efficacy of intravenous ibuprofen for treatment of pain in pediatric patients undergoing tonsillectomy.

BACKGROUND: Tonsillectomy is one of the most common pediatric procedures in the United States. An optimal perioperative pain control regimen remains a challenge. Intravenous ibuprofen administered at induction of anesthesia may be a safe and efficacious option for postoperative tonsillectomy pain. OBJECTIVES: To determine whether preoperative administration of intravenous ibuprofen (IV-ibuprofen) can significantly decrease the number of doses of postoperative fentanyl when compared with placebo in pediatric tonsillectomy surgical patients. METHODS: This was a multicenter, randomized, double-blind placebo-controlled trial conducted at six hospitals in the United States. A total of 161 pediatric patients aged 6-17 years undergoing tonsillectomy were randomized to receive either a single preoperative dose of 10 mg·kg(-1) IV-ibuprofen or placebo (normal saline). Postoperative pain was managed with intravenous fentanyl (0.5 µg·kg(-1)) on an as needed basis when the visual analog scale (VAS) was >30 mm and deemed appropriate by recovery room nurse/physician. The primary endpoint was the number of doses and amount of postoperative fentanyl administered postoperatively for rescue analgesia. RESULTS: There was a significant reduction in the number of postoperative doses and the amount of fentanyl administered after surgery in the IV-ibuprofen group compared with the placebo group (P = 0.021). There were no differences in the time to first analgesia request or the number of patients who required postoperative analgesia. There were no significant differences in the incidence of serious adverse events, surgical blood loss (P = 0.662), incidence of postoperative bleeding, or a need for surgical re-exploration between the treatment groups. CONCLUSION: Administration of IV-ibuprofen, 10 mg·kg(-1) , significantly reduced fentanyl use in pediatric tonsillectomy patients.

Long Term Outcomes After Renal Revascularization for Atherosclerotic Renovascular Disease in the ASTRAL Trial.

BACKGROUND: The ASTRAL trial (Angioplasty and Stenting for Renal Artery Lesions) recruited 806 patients between 2000 and 2007. Patients with atherosclerotic renal artery stenosis (RAS) and clinician uncertainty about the benefit of revascularization were randomized 1:1 to medical therapy with or without renal artery stenting. The initial results were presented in 2009 at a median 33.6-month follow-up, with no benefit of revascularization on renal or cardiovascular outcomes. Surviving patients remained under follow-up until the end of 2013, and the long-term results are presented in this study. METHODS: Data were analyzed to assess whether there was a later impact of revascularization on renal function, cardiovascular events, and survival, including a composite outcome of renal and cardiovascular outcomes and death (as in the CORAL trial [Cardiovascular Outcomes in Renal Atherosclerotic Lesions]). Prespecified subgroup analyses included different categories of renal function, rapid deterioration in kidney function, and degree of RAS. Post hoc analyses of patients with severe RAS (bilateral 70% or >70% in a solitary kidney), those with or without proteinuria, and a per-protocol analysis were performed. RESULTS: The mean age of the entry population was 70.5 years, the mean estimated glomerular filtration rate was 40 mL/min/1.73 m2, the mean RAS was 76%, and the mean blood pressure was 150/76 mm Hg; 83% of the revascularization group underwent attempted stenting. The median follow-up was 56.4 months, with 108 patients lost to follow-up. By the end of follow-up, 50% of the evaluable population had died, 18% had suffered a first renal event, and 40% had suffered a first cardiovascular event. No statistical difference was observed for any outcome in the intention-to-treat and per-protocol analyses. CONCLUSIONS: The long-term follow-up of the ASTRAL trial showed no overall benefit of renal revascularization to renal and cardiovascular outcomes. It has been highlighted that a proportion of the population had lower-risk RAS, and there is likely to be merit in further study in a higher-risk population. REGISTRATION: URL: https://www.isrctn.com; Unique identifier: ISRCTN59586944.

Model-Based Benefit/Risk Analysis for the Copanlisib Intermittent Dosing Regimen.

Copanlisib is an intravenously administered phosphatidylinositol 3-kinase (PI3K) inhibitor, which is approved as monotherapy for relapsed follicular lymphoma in adult patients who have received at least two systemic therapies. In an April 2022 US Food and Drug Administration (FDA) Oncology Drug Advisory Committee (ODAC), the benefit-risk profile of the class PI3K inhibitors were scrutinized for use in hematological malignancies. Specifically, their unique toxicities may contribute to the high incidences in reported serious and high-grade treatment emergent adverse events (TEAEs), thereby reducing their overall tolerability and potentially limiting their successful use. These tolerability concerns may be contributed by or compounded by inadequate dose optimization. The recommended dosing regimen of copanlisib 60 mg administered on days 1, 8, and 15 of a 28-day cycle was selected as the maximal tolerated dose (MTD) during phase I. Thus, this analysis sought to justify the copanlisib dose regimen selection. Copanlisib exposure-efficacy relationships were considered from its large phase III trial, CHRONOS-3, whereas copanlisib safety was investigated by pooling data across its two large clinical trials to comprehensively assess its exposure-safety relationships. Results demonstrated a statistically significant positive linear exposure-efficacy relationship at the MTD. Exposure-safety analyses revealed a borderline significant linear relationship for grade ≥3 TEAEs and no significant exposure-safety relationships for other investigated safety end points. The model-based benefit/risk framework considered the established exposure-response models and defined clinical utility function which confirmed the appropriateness of the copanlisib dosing regimen across the range of its achieved exposures.

Copanlisib population pharmacokinetics from phase I-III studies and exposure-response relationships in combination with rituximab.

Copanlisib dose selection was established under the maximum tolerated dose paradigm, and no dedicated dose-finding studies have investigated copanlisib dose selection when used in combination with rituximab. In CHRONOS-3, copanlisib plus rituximab demonstrated significantly improved progression-free survival versus placebo plus rituximab in patients with relapsed indolent non-Hodgkin lymphoma (iNHL). We conducted a comprehensive investigation of copanlisib population pharmacokinetics (PopPK) from a pooled analysis of 712 patients across nine copanlisib phase I-III studies and exposure-response (ER) relationships for efficacy and safety from the 1-year follow-up of CHRONOS-3. PopPK analyses examined the impact of demographic, laboratory, and comedication covariates on copanlisib between-patient PK variability. Individual static and time-varying exposure estimates were derived to investigate exposure-efficacy and exposure-safety relationships. Multivariate Cox proportional hazards and logistic regression analyses examined ER relationships with consideration of predefined potentially prognostic demographic-, laboratory-, and/or disease-related baseline covariates. Copanlisib PK were best described by a three-compartment model with first-order elimination. Individual identified covariates had modest effects on copanlisib PK and were generally in line with known copanlisib disposition properties. In CHRONOS-3, ER analyses showed a significant relationship between time-varying exposure estimates and progression-free survival, and no significant exposure-safety relationships. Thus, lower copanlisib doses may result in reduced efficacy but not necessarily improved safety or tolerability. These outcomes substantiate the current intermittent dosing regimen of copanlisib 60 mg on days 1, 8, and 15 of a 28-day cycle and support the observed clinical results of copanlisib in combination with rituximab in the iNHL population.

Model-informed approach to support pediatric dosing for the pan-PI3K inhibitor copanlisib in children and adolescents with relapsed/refractory solid tumors.

Copanlisib is an intravenously administered phosphatidylinositol 3-kinase (PI3K) inhibitor which was investigated in pediatric patients with relapsed/refractory solid tumors. A model-informed approach was undertaken to support and confirm an empirically selected starting dose of 28 mg/m2 for pediatric patients ≥1 year old, corresponding to 80% of the adult recommended dose adjusted for body surface area. An adult physiologically based pharmacokinetic (PBPK) model was initially established using copanlisib physicochemical and disposition properties and clinical pharmacokinetics (PK) data and was shown to adequately capture clinical PK across a range of copanlisib doses in adult cancer patients. The adult PBPK model was then extended to the pediatric population through incorporation of age-dependent anatomical and physiological changes and used to simulate copanlisib exposures in pediatric cancer patient age groups. The pediatric PBPK model predicted that the copanlisib 28 mg/m2 dose would achieve similar copanlisib exposures across pediatric ages when compared with historical adult exposures following the approved copanlisib 60 mg dose administered on Days 1, 8, and 15 of a 28-day cycle. Clinical PK were collected from a phase I study in pediatric patients with relapsed/refractory solid tumors (aged ≥4 years). An established adult population PK model was extended to incorporate an allometrically-scaled effect of body surface area and confirmed that the copanlisib maximum tolerated dose of 28 mg/m2 was appropriate to achieve uniform copanlisib exposures across the investigated pediatric age range and consistent exposures to historical data in adult cancer patients. The model-informed approach successfully supported and confirmed the copanlisib pediatric dose recommendation.

Human astrocytes and microglia show augmented ingestion of synapses in Alzheimer's disease via MFG-E8.

Synapse loss correlates with cognitive decline in Alzheimer's disease (AD). Data from mouse models suggests microglia are important for synapse degeneration, but direct human evidence for any glial involvement in synapse removal in human AD remains to be established. Here we observe astrocytes and microglia from human brains contain greater amounts of synaptic protein in AD compared with non-disease controls, and that proximity to amyloid-ß plaques and the APOE4 risk gene exacerbate this effect. In culture, mouse and human astrocytes and primary mouse and human microglia phagocytose AD patient-derived synapses more than synapses from controls. Inhibiting interactions of MFG-E8 rescues the elevated engulfment of AD synapses by astrocytes and microglia without affecting control synapse uptake. Thus, AD promotes increased synapse ingestion by human glial cells at least in part via an MFG-E8 opsonophagocytic mechanism with potential for targeted therapeutic manipulation.