Dupilumab Efficacy in Steroid-Dependent Severe Asthma by Baseline Oral Corticosteroid Dose.

BACKGROUND: Dupilumab, a fully human monoclonal antibody, blocks the shared receptor component for interleukin-4/-13, key and central drivers of type 2 inflammation in multiple diseases. In the phase 3 LIBERTY ASTHMA VENTURE (VENTURE) study (NCT02528214), dupilumab versus placebo reduced oral corticosteroid (OCS) dose and improved clinical outcomes in patients with OCS-dependent severe asthma. Dupilumab efficacy in patients with varying disease burden (defined by baseline OCS dose) has not been assessed. OBJECTIVE: This post hoc analysis of VENTURE evaluated dupilumab efficacy across subgroups defined by baseline OCS dose. METHODS: The OCS dose, proportion no longer needing OCS at week 24, annualized severe exacerbation rate, and least squares mean change from baseline in pre- and post-bronchodilator forced expiratory volume in 1 second at week 24 were evaluated in VENTURE patients with OCS-dependent severe asthma receiving dupilumab 300 mg every 2 weeks versus placebo, categorized by a baseline OCS dose of less than 10 mg/d or 10 or more mg/d. RESULTS: Dupilumab reduced daily OCS dose from baseline at week 24 in both dose groups. In dupilumab-/placebo-treated patients with a baseline OCS dose of less than 10 mg/d and 10 or more mg/d, 72%/42% and 37%/23% stopped OCS by week 24 (P < .01/P < .05), respectively. Dupilumab significantly reduced the annualized severe exacerbation rate by 71% and 48% (P < .01/P < .05). At week 24, dupilumab improved pre- and post-bronchodilator forced expiratory volume in 1 second in patients in both dose groups. CONCLUSIONS: In patients with OCS-dependent severe asthma receiving lower or higher baseline OCS doses, dupilumab significantly reduced the OCS dose and improved the likelihood of no longer requiring OCS while also reducing exacerbations and improving lung function.

Sustained reduction of serum neurofilament light chain over 7 years by alemtuzumab in early relapsing-remitting MS.

BACKGROUND: Alemtuzumab efficacy and safety was demonstrated in CARE-MS I and extension studies (CAMMS03409; TOPAZ). OBJECTIVE: Evaluate serum neurofilament light chain (sNfL) in CARE-MS I patients and highly active disease (HAD) subgroup, over 7 and 2 years for alemtuzumab and subcutaneous interferon beta-1a (SC IFNB-1a), respectively. METHODS: Patients received SC IFNB-1a 44 µg 3×/week or alemtuzumab 12 mg/day at baseline and month 12, with further as-needed 3-day courses. sNfL was measured using single-molecule array (Simoa™). HAD definition was ⩾2 relapses in year before randomization and ⩾1 baseline gadolinium-enhancing lesion. RESULTS: Baseline median sNfL levels were similar in alemtuzumab (n = 354) and SC IFNB-1a-treated (n = 159) patients (31.7 vs 31.4 pg/mL), but decreased with alemtuzumab versus SC IFNB-1a until year 2 (Y2; 13.2 vs 18.7 pg/mL; p < 0.0001); 12.7 pg/mL for alemtuzumab at Y7. Alemtuzumab-treated patients had sNfL at/below healthy control median at Y2 (72% vs 47%; p < 0.0001); 73% for alemtuzumab at Y7. HAD patients (n = 102) had higher baseline sNfL (49.4 pg/mL) versus overall population; alemtuzumab HAD patients attained similar levels (Y2, 12.8 pg/mL; Y7, 12.7 pg/mL; 75% were at/below control median at Y7). CONCLUSION: Alemtuzumab was superior to SC IFNB-1a in reducing sNfL, with levels in alemtuzumab patients remaining stable through Y7. CLINICALTRIALS.GOV IDENTIFIER: NCT00530348, NCT00930553, NCT02255656.

A double-blind, randomized trial to evaluate the pharmacokinetics and tolerability of 30 or 40 mg/d oral olanzapine relative to 20 mg/d oral olanzapine in stable psychiatric subjects.

BACKGROUND: Prescription monitoring in the United States suggests that oral olanzapine is prescribed in doses that exceed the approved range of 5 to 20 mg/d. OBJECTIVE: In this double-blind, randomized study, the pharmacokinetics and tolerability of higher-dose (30 or 40 mg/d) olanzapine were examined relative to the highest approved dose (20 mg/d) among non-treatment-resistant patients with psychiatric illnesses. METHODS: After a 10-day period in which all patients were stabilized on 20 mg/d olanzapine, 37 patients with schizophrenia, schizoaffective disorder, or bipolar I disorder were randomized to receive treatment with olanzapine 20 mg/d for 20 days (group A, n=12), 30 mg/d for 10 days followed by 40 mg/d for 10 days (group B, n=11), or 40 mg/d for 20 days (group C, n=14). On days 10, 20, and 30, blood samples were collected before dosing and at 1, 2, 5, 6, 10, 14, 18, and 24 hours after dosing. Plasma olanzapine concentrations were assayed using high-performance liquid chromatography with electrochemical detection. Tolerability was assessed by spontaneously reported treatment-emergent adverse events; changes from baseline in vital signs, electrocardiograms, and standard laboratory test values; incidences of categorically defined treatment-emergent akathisia and parkinsonism; and 2-hour standard oral glucose tolerance tests. RESULTS: Of the 53 subjects who entered the study, 16 were excluded (7 because entry criteria were not met, 6 because of subject's decision, and 3 for other reasons). Subjects were primarily men (group A, 75%; group B, 55%; group C, 79%), approximately 40 years old (mean [SD] age: group A, 40.6 [8.6]; group B, 37.9 [8.6]; group C, 39.4 [9.2] years), and black (group A, 83%; group B, 55%; group C, 64% [the remainder were white]). Mean (SD) baseline weight was 84.0 (17.5) kg for group A, 82.1 (12.0) kg for group B, and 100.9 (23.3) kg for group C. By day 20, dose-proportional increases were observed in plasma olanzapine Cmax,ss and AUC. Geometric mean (percent coefficient of variation) values for groups A, B, and C at day 20 were as follows: Cmax,ss 57.8 (40.2), 75.6 (86.7), and 94.1 (50.2) ng/mL, respectively; and AUC: 997 (38.5), 1220 (88.0), and 1630 (53.9) ng . h/mL, respectively. The most frequently reported adverse events were weight gain (group A, 2/12 [17%]; group B, 3/11 [27%]; group C, 2/14 [14%]) and sedation (group A, 3/12 [25%]; group B, 2/11 [18%]; group C, 2/14 [14%]). Mean (SD) weight gain from baseline to end point was 3.5 (2.81) kg for group A, 3.0 (3.15) kg for group B, and 3.1 (2.22) kg for group C. Changes in glucose tolerance, vital signs, or laboratory parameters did not appear to be dose dependent. During double-blind therapy, 7 subjects experienced akathisia (spontaneously reported, n=3 [group C]; categorically defined, n=3 [group B]; both, n=1 [group C]). Of the subjects with categorically defined akathisia, 2 had a history of akathisia and the other had a score of 1 (questionable) on the Barnes Akathisia Scale at baseline. No cases of parkinsonism were observed at any time. CONCLUSIONS: Among these subjects with psychiatric illnesses, olanzapine at doses of 30 and 40 mg/d displayed a pharmacokinetic profile consistent with that of 20 mg/d. Higher-dose olanzapine exhibited a tolerance profile similar to that of 20 mg/d; however, akathisia may be more likely to occur at higher doses, particularly in subjects with a history of akathisia.

Reelin promoter hypermethylation in schizophrenia.

Reelin mRNA and protein levels are reduced by approximately 50% in various cortical structures of postmortem brain from patients diagnosed with schizophrenia or bipolar illness with psychosis. In addition, the mRNA encoding the methylating enzyme, DNA methyltransferase 1, is up-regulated in the same neurons that coexpress reelin and glutamic acid decarboxylase 67. We have analyzed the extent and pattern of methylation within the CpG island of the reelin promoter in genomic DNA isolated from cortices of schizophrenia patients and nonpsychiatric subjects. Ten (The Stanley Foundation Neuropathology Consortium) and five (Harvard Brain Collection) schizophrenia patients and an equal number of nonpsychiatric subjects were selected from each brain collection. Genomic DNA was isolated, amplified (from base pair -527 to base pair +322) after bisulphite treatment, and sequenced. The results show that within the promoter region there were interesting regional variations. There was increased methylation at positions -134 and 139, which is particularly important for regulation, because this portion of the promoter is functionally competent based on transient transfection assays. This promoter region binds a protein present in neuronal precursor nuclear extracts that express very low levels of reelin mRNA; i.e., an oligonucleotide corresponding to this region and that contains methylated cytosines binds more tightly to extracts from nonexpressing cells than the nonmethylated counterpart. Collectively, the data show that this promoter region has positive and negative properties and that the function of this complex cis element relates to its methylation status.

Differential effects of removing the glucose or saccharin components of a glucose-saccharin mixture in a successive negative contrast paradigm.

When rats experience an unexpected decrease in reward value, e.g., from 32% sucrose to 4% sucrose, consummatory behavior abruptly decreases to a level below control subjects that only experience the lesser reward, a phenomenon known as Successive Negative Contrast (SNC). In food deprived rats experiencing downshifts in sucrose concentration, SNC dissipates in 3-4 days, as consummatory behavior in shifted rats recovers to the level of unshifted controls. In Experiment 1 food deprived rats that were given 5 min daily access to a 2% glucose-0.15% saccharin mixture, and subsequently shifted to 2% glucose alone, displayed a dramatic SNC effect relative to rats that only received 2% glucose. This SNC effect was primarily manifested as a decrease in the number of consummatory bursts initiated. Interestingly, intake failed to recover to control levels during eight daily postshift sessions. However, in Experiment 2 subjects that were shifted from the same glucose-saccharin mixture to 0.15% saccharin alone failed to show SNC rather, intake fell to the level of control animals which only received 0.15% saccharin. The data from Experiment 1, in conjunction with previous studies utilizing non-deprived rats, quinine adulteration, or shifts from sucrose to saccharin, show that reductions in taste value can produce contrast effects, but suggest that a threshold caloric value is necessary for recovery. The data from Experiment 2 may suggest that saccharin and glucose do not contribute equally to the enhanced palatability of the mixture.

Histone deacetylase inhibitors decrease reelin promoter methylation in vitro.

We investigated the effects of agents that induce reelin mRNA expression in vitro on the methylation status of the human reelin promoter in neural progenitor cells (NT2). NT2 cells were treated with the histone deacetylase inhibitors, trichostatin A (TSA) and valproic acid (VPA), and the methylation inhibitor aza-2'-deoxycytidine (AZA) for various times. All three drugs reduced the methylation profile of the reelin promoter relative to untreated cells. The acetylation status of histones H3 and H4 increased following treatment with VPA and TSA at times as short as 15 min following treatment; a result consistent with the reported mode of action of these drugs. Chromatin immunoprecipitation experiments showed that these changes were accompanied by changes occurring at the level of the reelin promoter as well. Interestingly, AZA decreased reelin promoter methylation without concomittantly increasing histone acetylation. In fact, after prolonged treatments with AZA, the acetylation status of histones H3 and H4 decreased relative to untreated cells. We also observed a trend towards reduced methylated H3 after 18 h treatment with TSA and VPA. Our data indicate that while TSA and VPA act to increase histone acetylation and reduce promoter methylation, AZA acts only to decrease the amount of reelin promoter methylation.

Neonatal lesions of the ventral hippocampal formation alter GABA-A receptor subunit mRNA expression in adult rat frontal pole.

BACKGROUND: Gamma-aminobutyric acid (GABA)-ergic function is altered in schizophrenia. Of particular interest is the altered central nervous system expression of GABA-A receptor subunits, as changes in subunit expression account for recognized differences in mammalian brain function making them inviting targets for novel psychotropic agents. Excitotoxic neonatal lesions of the ventral hippocampal formation (NVHL) in rats reproduce numerous aspects of schizophrenia, including decreased mRNA expression of the GABA synthesizing enzyme glutamic acid decarboxylase-67, though their impact on subunit expression is unknown. METHODS: We utilized quantitative reverse transcription polymerase chain reaction to investigate mRNA expression of the alpha1, alpha5, and gamma2s GABA-A receptor subunits in the frontal pole of water-deprived adult NVHL and SHAM-lesioned animals. RESULTS: Messenger RNA expression for all three GABA-A subunits (alpha1-NVHL: 18.5 +/- 1.6 pg/mug total pooled RNA, SHAM: 11.3 +/- .4; alpha5-NVHL: 5.1 +/- .6; SHAM: 3.5 +/- .7; and gamma2s-NVHL: 10.8 +/- 1.7; SHAM: 7.2 +/- 1.5) was higher in NVHL, though only levels of alpha1 differed significantly after correction for multiple comparisons. Levels of a control mRNA, neuronal specific enolase, were similar in the two groups. CONCLUSIONS: These data indicate that NVHL reproduce changes in cortical GABA-A receptor subunit expression seen in schizophrenia, suggesting this animal model may facilitate efforts to clarify the physiologic significance of altered GABA function and to develop novel targets for therapeutic interventions.

Evidence for zolpidem-induced hyperphagia, but not anxiolysis, in a successive negative contrast paradigm.

Zolpidem is an imidazopyridine which binds to certain benzodiazepine receptor types with varying degrees of affinity. The effect of zolpidem on successive negative contrast was investigated in three experiments. In each experiment, a contrast group was given brief access to 32% sucrose for 10 days, then shifted to 4% sucrose for 2 days; a procedure that elicits anxiety primarily on the second postshift day. One control group was given only 4% sucrose. Experiments 2 and 3 included a 2% sucrose group as an intake rate-dependent control. In Experiment 1, zolpidem (4.0 and 0.5 mg/kg) dose-dependently reduced contrast on the two postshift days. Contrast occurred during the first postshift consummatory burst. Zolpidem prolonged the first postshift burst equally in both shifted and unshifted groups, suggesting a general facilitation of intake masked by a ceiling effect in controls. In Experiment 2, zolpidem's (4.0 mg/kg) anti-contrast action was equivalent to its hyperphagic effect in the 2% control group. Zolpidem prolonged the first postshift burst equally in all three groups, again consistent with general intake facilitation. In Experiment 3, 8.0 mg/kg zolpidem produced an anti-contrast effect not present in 2% controls on both postshift days. This does not appear attributable to anxiolysis, however, as the effect was equivalent during stressful and non-stressful phases of the postshift period, and zolpidem extended the duration of the first postshift burst equally in all three sucrose groups. Thus, unlike benzodiazepines, zolpidem is not anxiolytic in this paradigm.

Neonatal lesions of the ventral hippocampal formation disrupt neuroendocrine responses to auditory stress in the adult rat.

Lesioning the ventral hippocampal formation (vHF) in the neonatal rat with an excitotoxin replicates several features of schizophrenia. Similar lesions in the adult rat disrupt the normal constraint of neuroendocrine responses to environmental stressors, which is of potential interest because the enhanced HPA axis and antidiuretic hormone activity in schizophrenia is linked to acute stress and hippocampal formation (HF) pathology. In the current study, we investigated the effects of neonatal ventral hippocampal formation lesions (NVHFL) on plasma adrenocorticotropin hormone (ACTH) and arginine vasopressin (AVP) responses following a 2-min acoustic stressor in the adult rat. Levels of the two hormones did not differ between SHAM-operated and NVHFL animals in their home cages. ACTH levels doubled in SHAM-operated animals immediately following stress, but increased more than six-fold in the NVHFL group. AVP levels were halved immediately following stress in SHAM-operated animals, but did not change significantly in NVHFL. Findings could not be attributed to intervening factors known to influence neuroendocrine activity. Thus, NVHFL appear to disrupt the HF-mediated constraint of neuroendocrine responses to stress, and model the neuroendocrine dysfunction seen in schizophrenia. We posit that clarification of how NVHFL alters relatively "simple", well characterized, and phylogenetically preserved systems, such as the neuroendocrine system, may provide insight into the mechanism of hippocampal pathology in schizophrenia.

What is the functional significance of hippocampal pathology in schizophrenia?

The hippocampal formation (HF) is one of the brain structures most consistently altered in schizophrenia, yet the contribution of HF pathology to severe mental illness is poorly understood. We present evidence that our current ignorance is attributable to the fact that the anterior HF is heavily involved in schizophrenia but has been inadequately examined by schizophrenia investigators. We propose that the anterior HF in humans, and its counterpart in rodents (ventral HF), constrain diverse responses to psychological stimuli and that disruption of this function contributes to schizophrenia. While current data suggest that hallmark symptoms of schizophrenia most likely result from the role of the anterior HF in the integrated neurocircuit that includes the prefrontal cortex, ventral striatum, and ventral tegmental area, better characterized and phylogenetically preserved neurocircuits may be similarly affected by anterior HF pathology and account for associated findings of the disorder. We propose that focusing on the impact of ventral HF pathology on these simpler circuits and functions in rodents may provide insight into the pathophysiology of severe mental illness in humans. We review several associated findings in schizophrenia to assess the likelihood that each could be a product of this putative anterior HF dysfunction and could therefore be productively studied in rodents by probing ventral HF function.

GABAergic cortical neuron chromatin as a putative target to treat schizophrenia vulnerability.

Inhibitory GABAergic interneurons of prefrontal cortex (PFC) appear to play an important role in the regulation of intermittent pyramidal neuron columnary firing and in the neuronal plasticity that mediate cognitive functions. In schizophrenia (SZ), cognitive defects and dysfunctions in pyramidal neuronal columnary firing appear to depend on abnormalities of GABAergic neurons. These abnormalities include a decrease of GAD67 and reelin expression, which result in a reduction of cortical inhibitory input to spine postsynaptic densities as a result of the decrease of GABA concentration at the synaptic cleft, and of neurotrophic stimuli as a result of the decrease of reelin secreted into the extracellular matrix. Our studies show that alterations in chromatin remodeling related to a selective upregulation of DNA-5-cytosine methyltransferase (DNMT) expression in GABAergic neurons of SZ PFC may induce a hypermethylation of reelin and GAD67 promoter CpG islands, which downregulates their expression. In addition, we report preliminary evidence suggesting that by targeting this chromatin-remodeling deficit with inhibitors of histone deacetylases (HDAC), it may be possible to reduce the DNMT upregulation via a covalent modification of nucleosomal histone tails, underscoring the possibility that by addressing a chromatin remodeling deficit, one may treat psychiatric disorders.