Brain-Derived Neurotrophic Factor: A Novel Dynamically Regulated Therapeutic Modulator in Neurological Disorders.

The growth factor brain-derived neurotrophic factor (BDNF), and its receptor tropomyosin-related kinase receptor type B (TrkB) play an active role in numerous areas of the adult brain, where they regulate the neuronal activity, function, and survival. Upregulation and downregulation of BDNF expression are critical for the physiology of neuronal circuits and functioning in the brain. Loss of BDNF function has been reported in the brains of patients with neurodegenerative or psychiatric disorders. This article reviews the BDNF gene structure, transport, secretion, expression and functions in the brain. This article also implicates BDNF in several brain-related disorders, including Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, major depressive disorder, schizophrenia, epilepsy and bipolar disorder.

Emerging Targets for Modulation of Immune Response and Inflammation in Stroke.

The inflammatory and immunological responses play a significant role after stroke. The innate immune activation stimulated by microglia during stroke results in the migration of macrophages and lymphocytes into the brain and are responsible for tissue damage. The immune response and inflammation following stroke have no defined targets, and the intricacies of the immunological and inflammatory processes are only partially understood. Innate immune cells enter the brain and meninges during the acute phase, which can cause ischemia damage. Activation of systemic immunity is caused by danger signals sent into the bloodstream by injured brain cells, which is followed by a significant immunodepression that encourages life-threatening infections. Neuropsychiatric sequelae, a major source of post-stroke morbidity, may be induced by an adaptive immune response that is initiated by antigen presentation during the chronic period and is directed against the brain. Thus, the current review discusses the role of immune response and inflammation in stroke pathogenesis, their role in the progression of injury during the stroke, and the emerging targets for the modulation of the mechanism of immune response and inflammation that may have possible therapeutic benefits against stroke.

Vitamin D as therapeutic modulator in cerebrovascular diseases: a mechanistic perspectives.

Vitamin D deficiency has been linked to several major chronic diseases, such as cardiovascular and neurodegenerative diseases, diabetes, and cancer, linked to oxidative stress, inflammation, and aging. Vitamin D deficiency appears to be particularly harmful to the cardiovascular system, as it can cause endothelial dysfunctioning and vascular abnormalities through the modulation of various downstream mechanisms. As a result, new research indicates that therapeutic approaches targeting vitamin D inadequacies or its significant downstream effects, such as impaired autophagy, abnormal pro-inflammatory and pro-oxidant reactions, may delay the onset and severity of major cerebrovascular disorders such as stroke and neurologic malformations. Vitamin D modulates the various molecular pathways, i.e., Nitric Oxide, PI3K-Akt Pathway, cAMP pathway, NF-kB Pathway, Sirtuin 1, Nrf2, FOXO, in cerebrovascular disorder. The current review shows evidence for vitamin D's mitigating or slowing the progression of these cerebrovascular disorders, which are significant causes of disability and death worldwide.

Mechanistic Insight on Autophagy Modulated Molecular Pathways in Cerebral Ischemic Injury: From Preclinical to Clinical Perspective.

Cerebral ischemia is one of the most devastating brain injuries and a primary cause of acquired and persistent disability worldwide. Despite ongoing therapeutic interventions at both the experimental and clinical levels, options for stroke-related brain injury are still limited. Several evidence suggests that autophagy is triggered in response to cerebral ischemia, therefore targeting autophagy-related signaling pathways can provide a new direction for the therapeutic implications in the ischemic injury. Autophagy is a highly conserved lysosomal-dependent pathway that degrades and recycles damaged or non-essential cellular components to maintain neuronal homeostasis. But, whether autophagy activation promotes cell survival against ischemic injury or, on the contrary, causes neuronal death is still under debate. We performed an extensive literature search from PubMed, Bentham and Elsevier for various aspects related to molecular mechanisms and pathobiology involved in autophagy and several pre-clinical studies justifiable further in the clinical trials. Autophagy modulates various downstream molecular cascades, i.e., mTOR, NF-κB, HIF-1, PPAR-γ, MAPK, UPR, and ROS pathways in cerebral ischemic injury. In this review, the various approaches and their implementation in the translational research in ischemic injury into practices has been covered. It will assist researchers in finding a way to cross the unbridgeable chasm between the pre-clinical and clinical studies.

Calpain Inhibitors as Potential Therapeutic Modulators in Neurodegenerative Diseases.

It is considered a significant challenge to understand the neuronal cell death mechanisms with a suitable cure for neurodegenerative disorders in the coming years. Calpains are one of the best-considered "cysteine proteases activated" in brain disorders. Calpain is an important marker and mediator in the pathophysiology of neurodegeneration. Calpain activation being the essential neurodegenerative factor causing apoptotic machinery activation, it is crucial to develop reliable and effective approaches to prevent calpain-mediated apoptosis in degenerating neurons. It has been recently seen that the "inhibition of calpain activation" has appeared as a possible therapeutic target for managing neurodegenerative diseases. A systematic literature review of PubMed, Medline, Bentham, Scopus, and EMBASE (Elsevier) databases was conducted. The present article reviews the basic pathobiology and role of selective calpain inhibitors used in various neurodegenerative diseases as a therapeutic target.

Neuroprotective Effect of Piclamilast-Induced Post-Ischemia Pharmacological Treatment in Mice.

Various studies have evidenced the neuroprotective role of PDE4 inhibitors. However, whether PDE4 inhibitor, Piclamilast pharmacological post-treatment is protective during cerebral ischemia reperfusion-induced injury remains unknown. Therefore, this study design included testing the hypothesis that Piclamilast administered at the beginning of a reperfusion phase (Piclamilast pPost-trt) shows protective effects and explores & probes underlying downstream mechanisms. Swiss albino male mice were subjected to global ischemic and reperfusion injury for 17 min. The animals examined cerebral infarct size, biochemical parameters, inflammatory mediators, and motor coordination. For memory, assessment mice were subjected to morris water maze (MWM) and elevated plus maze (EPM) test. Histological changes were assessed using HE staining. Piclamilast pPost-trt significantly reduced I/R injury-induced deleterious effects on biochemical parameters of oxidative stress, inflammatory parameters, infarct size, and histopathological changes, according to the findings. These neuroprotective effects of pPost-trt are significantly abolished by pre-treatment with selective CREB inhibitor, 666-15. Current study concluded that induced neuroprotective benefits of Piclamilast Post-trt, in all probability, maybe mediated through CREB activation. Hence, its neuroprotective effects can be further explored in clinical settings.

Therapeutic implications of sonic hedgehog pathway in metabolic disorders: Novel target for effective treatment.

Hedgehog, a developmental morphogen, and its downstream signalling have recently been associated with metabolic control. Sonic hedgehog signalling (Shh) is a significant pathway that regulates various events during the growth and development of embryos. The dysregulation of the Shh pathway has been implicated in many physiological and pathological processes, including adipocyte differentiation, cancer, diabetes and obesity. Researchers have proved that pharmacological modulation of the Shh pathway might help to improve better outcomes in metabolic disorders. A systemic review was conducted through various search engines to understand the molecular nature of Shh Pathway in Metabolic Disorders and its therapeutic implication in the future. However, we could find that by studying the crosstalk between various pathways, such as Wnt/ ß-catenin, TGF (transforming growth factor ß), mTOR, and notch with Sonic hedgehog, a close link between the pathogenesis of different metabolic disorders. Understanding the importance of these molecular interlinking networks will provide a rational basis that influences its activity. This article discusses the changes and modifications that happen due to up-or down-regulation of various transcription factors in the Shh pathway. The study attempts to provide a complete overview of the main signalling events involved with canonical and non-canonical Hedgehog signalling and the increasingly complicated regulatory modalities related to Hedgehog for regulating metabolism. Further, it investigates the possible approaches needed to treat metabolic disorders for better results.

Therapeutic implications of cyclooxygenase (COX) inhibitors in ischemic injury.

INTRODUCTION: Ischemia-reperfusion injury (IRI) is the inexplicable aggravation of cellular dysfunction that results in blood flow restoration to previously ischemic tissues. COX mediates the oxidative conversion of AA to various prostaglandins and thromboxanes, which are involved in various physiological and pathological processes. In the pathophysiology of I/R injuries, COX has been found to play an important role. I/R injuries affect most vital organs and are characterized by inflammation, oxidative stress, cell death, and apoptosis, leading to morbidity and mortality. MATERIALS AND METHODS: A systematic literature review of Bentham, Scopus, PubMed, Medline, and EMBASE (Elsevier) databases was carried out to understand the Nature and mechanistic interventions of the Cyclooxygenase modulations in ischemic injury. Here, we have discussed the COX Physiology and downstream signalling pathways modulated by COX, e.g., Camp Pathway, Peroxisome Proliferator-Activated Receptor Activity, NF-kB Signalling, PI3K/Akt Signalling in ischemic injury. CONCLUSION: This review will discuss the various COX types, specifically COX-1 and COX-2, which are involved in developing I/R injury in organs such as the brain, spinal cord, heart, kidney, liver, and intestine.

A comprehensive transcriptome analysis of contrasting rice cultivars highlights the role of auxin and ABA responsive genes in heat stress response.

Sensing a change in ambient temperature is key to survival among all living organisms. Temperature fluctuations due to climate change are a matter of grave concern since it adversely affects growth and eventually the yield of crop plants, including two of the major cereals, i.e., rice and wheat. Thus, to understand the response of rice seedlings to elevated temperatures, we performed microarray-based transcriptome analysis of two contrasting rice cultivars, Annapurna (heat tolerant) and IR64 (heat susceptible), by subjecting their seedlings to 37 °C and 42 °C, sequentially. The transcriptome analyses revealed a set of uniquely regulated genes and related pathways in red rice cultivar Annapurna, particularly associated with auxin and ABA as a part of heat stress response in rice. The changes in expression of few auxin and ABA associated genes, such as OsIAA13, OsIAA20, ILL8, OsbZIP12, OsPP2C51, OsDi19-1 and OsHOX24, among others, were validated under high-temperature conditions using RT-qPCR. In particular, the expression of auxin-inducible SAUR genes was enhanced considerably at both elevated temperatures. Further, using genes that expressed inversely under heat vs. cold temperature conditions, we built a regulatory network between transcription factors (TF) such as HSFs, NAC, WRKYs, bHLHs or bZIPs and their target gene pairs and determined regulatory coordination in their expression under varying temperature conditions. Our work thus provides useful insights into temperature-responsive genes, particularly under elevated temperature conditions, and could serve as a resource of candidate genes associated with thermotolerance or downstream components of temperature sensors in rice.

OsbZIP62/OsFD7, a functional ortholog of FLOWERING LOCUS D, regulates floral transition and panicle development in rice.

We have characterized a rice bZIP protein-coding gene OsbZIP62/OsFD7 that is expressed preferentially in the shoot apical meristem and during early panicle developmental stages in comparison with other OsFD genes characterized to date. Surprisingly, unlike OsFD1, OsFD7 interacts directly and more efficiently with OsFTLs; the interaction is strongest with OsFTL1 followed by Hd3a and RFT1, as confirmed by fluorescence lifetime imaging-Förster resonant energy transfer (FLIM-FRET) analysis. In addition, OsFD7 is phosphorylated at its C-terminal end by OsCDPK41 and OsCDPK49 in vitro, and this phosphorylated moiety is recognized by OsGF14 proteins. OsFD7 RNAi transgenics were late flowering; the transcript levels of some floral meristem identity genes (e.g. OsMADS14, OsMADS15, and OsMADS18) were also down-regulated. RNAi lines also exhibited dense panicle morphology with an increase in the number of primary and secondary branches resulting in longer panicles and more seeds, probably due to down-regulation of SEPALLATA family genes. In comparison with other FD-like proteins previously characterized in rice, it appears that OsFD7 may have undergone diversification during evolution, resulting in the acquisition of newer functions and thus playing a dual role in floral transition and panicle development in rice.

Mechanistic and physiological approaches of fecal microbiota transplantation in the management of NAFLD.

Non-alcoholic fatty liver disease (NAFLD) is a multifaceted disease allied with various metabolic disorders, obesity and dysbiosis. Gut microbiota plays an influential role in the pathogenesis of NAFLD and other metabolic disorders. However, recent scientific upsurge emphasizes on the utility of beneficial gut microbiota and bacteriotherapy in the management of NAFLD. Fecal microbiota transplantation (FMT) is the contemporary therapeutic approach with state-of-the-art methods for the treatment of NAFLD. Other potential therapies include probiotics and prebiotics supplements which are based on alteration of gut microbes to treat NAFLD. In this review, our major focus is on the pathological association of gut microbiota with progression of NAFLD, historical aspects and recent advances in FMT with possible intervention to combat NAFLD and its associated metabolic dysfunctions.

Pathobiological and molecular connections involved in the high fructose and high fat diet induced diabetes associated nonalcoholic fatty liver disease.

BACKGROUND: Poor dietary habits such as an over consumption of high fructose and high fat diet are considered as the major culprit for the induction of diabetes associated liver injury. Diabetes mellitus is a metabolic disorder that affects various vital organs of the body especially the kidney, brain, heart, and liver. The high fructose and high fat (HFHF) diet worsen the metabolic conditions by producing various pathogenic burdens such as oxidative stress, inflammation, etc. on liver. The hyperlipidemic and hyperglycemic conditions induced by HFHF diet leads to the generation of various proinflammatory mediators like TNFα, interleukin and cytokines. AIM AND METHODS: The systematic bibliographical literature survey was done with the help of PubMed, Google scholar and MedLine to identify all pathological and molecular concerened with HFHF induced diabetic liver injury. The consumption of HFHF diet leads to an increase in mitochondrial oxidative stress thereby decreases the liver protective antioxidants required for cell viability. HFHF diet disturbs lipid and lipoprotein clearance by elevating the level of apolipoprotein CIII and impairing the hydrolysis of triglyceride. As a result, there is an increase in free fatty acid concentration, triglycerides and diacylglycerol in the liver which further triggers the situation of insulin resistance. CONCLUSION: The focus of present review is based upon the various pathological, genetic and molecular mechanism involved in the development of high-fat high fructose diet induced diabetic liver injury. However, the current review also documented few shreds of evidence related to various microRNAs (miR-31, miR-33a, miR-34a, miR-144, miR-146b, miR-150) concerned to HFHF diet which play an important role in the pathogenesis of diabetes associated liver injury Dietary life style modification may prove beneficial in the management of various metabolic disorders.

Effect of grass sublingual tablet immunotherapy is similar in children and adults: A Bayesian approach to design pediatric sublingual immunotherapy trials.

BACKGROUND: Large sample sizes are needed for sublingual immunotherapy (SLIT) trials because of inherent data variability secondary to inconsistent allergen exposure. Obtaining large sample sizes for pediatric SLIT trials is challenging, but a Bayesian approach using prior adult data can reduce the necessary sample size. OBJECTIVE: We sought to describe how a Bayesian framework using prior information from adult trials can be used to improve pediatric SLIT clinical development. METHODS: Data were compiled by using a frequentist approach (conventional clinical trial approach independent of prior data) from trials conducted during the clinical development of timothy grass SLIT-tablets. RESULTS: The treatment effect of timothy grass SLIT-tablets was considered similar between pediatric (n = 795) and adult (n = 2299) data pools, with relative total combined symptom plus medication score improvement versus placebo of 21% (95% CI, 11.0% to 30.4%) and 20% (95% CI, 14.6% to 24.4%), respectively. Phleum pratense-specific IgG4 and IgE-blocking factor increased from baseline in both children and adults treated with timothy grass SLIT-tablets. Given the reasonable assumption in similarity of treatment response between adults and children, a Bayesian approach is described to demonstrate rigorous efficacy criteria for pediatric trials incorporating information from prior adult trials and thereby reduce the sample size. CONCLUSIONS: Data support the similarity of efficacy and immunologic changes between children and adults treated with SLIT for allergic rhinoconjunctivitis. Therefore it is appropriate to use data from adult trials to design feasible trials in children, which might reduce unsafe off-label use by promoting more quickly proper labeling of approved products.

Treatment effect of sublingual immunotherapy tablets and pharmacotherapies for seasonal and perennial allergic rhinitis: Pooled analyses.

BACKGROUND: Data comparing the treatment effect of allergy immunotherapy and pharmacotherapy are lacking. OBJECTIVE: We sought to indirectly compare the treatment effect of sublingual immunotherapy (SLIT)-tablets with pharmacotherapy for seasonal allergic rhinitis (SAR) and perennial allergic rhinitis (PAR). METHODS: Pooled data from randomized, double-blind, placebo-controlled trials for the clinical development programs of selected allergic rhinitis treatments were evaluated. Total nasal symptom scores (TNSSs) relative to placebo were compared. Subjects scored symptoms daily during entire pollen seasons in 6 timothy grass SLIT-tablet trials (n = 3094) and 2 ragweed SLIT-tablet trials (n = 658) and during the last 8 weeks of treatment in 2 house dust mite (HDM) SLIT-tablet trials (n = 1768). Subjects scored symptoms daily in 7 montelukast (10 mg, n = 6799), 9 desloratadine (5 mg, n = 4455), and 8 mometasone furoate nasal spray (MFNS; 200 µg daily, n = 2140) SAR or PAR trials. SLIT-tablet trials allowed rescue medication use, whereas most pharmacotherapy trials did not. A fixed-effect meta-analysis method estimated differences in on-treatment average TNSSs. RESULTS: In grass and ragweed SLIT-tablet trials, overall improvement in TNSSs relative to placebo was 16.3% and 17.1%, respectively. In HDM SLIT-tablet trials, TNSS overall improvement relative to placebo was 16.1%. In the montelukast, desloratadine, and MFNS trials, TNSS overall improvement relative to placebo was 5.4%, 8.5%, and 22.2%, respectively, for SAR trials, and 3.7%, 4.8%, and 11.2%, respectively, for PAR trials. CONCLUSIONS: Although comparisons were limited by study design heterogeneity and use of rescue medications in SLIT-tablet trials, effects on nasal symptoms with timothy grass and ragweed SLIT-tablets were nearly as great as with MFNS and numerically greater than with montelukast and desloratadine for SAR. HDM SLIT-tablet effects were numerically greater than all pharmacotherapies for PAR. SLIT-tablets offer the additional benefit of long-term efficacy.

Efficacy of house dust mite sublingual immunotherapy tablet in North American adolescents and adults in a randomized, placebo-controlled trial.

BACKGROUND: The house dust mite (HDM) sublingual immunotherapy (SLIT) tablet (MK-8237; Merck & Co, Kenilworth, NJ/ALK-Abelló, Hørsholm, Denmark) has demonstrated beneficial effects on allergic rhinoconjunctivitis and asthma outcomes in European trials. OBJECTIVE: This is the first trial to assess the efficacy/safety of HDM SLIT-tablets in North American subjects with HDM-induced allergic rhinitis with or without conjunctivitis (AR/C). METHODS: In this double-blind, multicenter trial (NCT01700192) 1482 subjects (aged ≥12 years) with HDM-induced AR/C with or without asthma were randomized to a daily SQ HDM SLIT-tablet (12 SQ-HDM dose) or placebo for up to approximately 52 weeks. A rhinitis daily symptom score (DSS; 4 nasal symptoms, maximum score = 12) of 6 or greater, or 5 or greater with 1 symptom being severe, on 5 of 7 consecutive days before randomization was required. The primary end point was the average total combined rhinitis score, which was defined as the rhinitis DSS plus rhinitis daily medication score (DMS), during the last 8 treatment weeks. RESULTS: Treatment with 12 SQ-HDM improved the total combined rhinitis score by 17% (95% CI, 10% to 25%) versus placebo. Improvements versus placebo in the secondary end points of average rhinitis DSS, rhinitis DMS, total combined rhinoconjunctivitis score, and visual analog scale-assessed AR/C symptoms were 16%, 18%, 17%, and 16%, respectively. All nominal P values were less than .001 versus placebo, except rhinitis DMS (P = 0.15). No treatment-related adverse events meeting the International Council on Harmonization definition of a serious adverse event were reported; 1 nonserious treatment-related systemic allergic reaction occurred (assessed as moderate intensity) at first administration under medical supervision and was treated with epinephrine. CONCLUSIONS: In the first North American trial of use of a SLIT-tablet for HDM allergy, 12 SQ-HDM was well tolerated and improved HDM-induced rhinitis symptoms in adults and adolescents.

Long-term effects of a house dust mite sublingual immunotherapy tablet in an environmental exposure chamber trial.

BACKGROUND: Treatment with SQ house dust mite (HDM) sublingual immunotherapy (SLIT) tablet is effective for HDM respiratory allergic disease, but data on long-term effects are lacking. OBJECTIVE: Post hoc analyses were conducted to determine the long-term effect of SQ HDM SLIT-tablet on nasal, ocular, and cough symptoms 1 year after discontinuation of treatment. METHODS: Study participants underwent environmental exposure chamber (EEC) challenges at baseline and week 24 in a randomized, placebo-controlled, double-blind trial (NCT01644617) during which participants received daily 12 SQ-HDM, 6 SQ-HDM, or placebo for 24 weeks. Asthma had to be stable, well controlled, and nonsevere. The mean total asthma symptom score (TASS; sum of 3 symptoms: cough, wheeze, and dyspnea) during baseline and week 24 EEC challenge was analyzed in all participants who completed the trial (n = 106). Approximately 1 year after trial completion, another EEC challenge was conducted in a subset of participants (n = 51). Total nasal symptom score (sum of 4 symptoms), total ocular symptom score (sum of 2 symptoms), and cough were assessed. RESULTS: Compared with baseline and end-of-treatment values, sustained improvement of all symptoms assessed at the 1-year follow-up EEC challenge was evident in participants treated with 12 SQ-HDM. Results with 6 SQ-HDM were less notable. After 24 weeks of 12 SQ-HDM, TASS during EEC challenge was improved 65% vs baseline; at 1-year follow-up, cough was improved 57% vs baseline. CONCLUSION: Persistent improvement of nasal and ocular symptoms was observed up to 1 year after completing 24 weeks of 12 SQ-HDM treatment. Beneficial effects on cough were also observed. TRIAL REGISTRATION: clinicaltrials.gov Identifier NCT01644617.

Safety of house dust mite sublingual immunotherapy standardized quality tablet in children allergic to house dust mites.

BACKGROUND: Sublingual immunotherapy (SLIT) tablets could be an important alternative to subcutaneous immunotherapy for house dust mite (HDM) allergy in children. OBJECTIVE: To characterize the safety, tolerability, and duration of local adverse events (AEs) of an HDM SLIT tablet (MK-8237; Merck, ALK Abellò, and Torii) in North American children 12 to 17 years old with HDM allergic rhinitis with and without conjunctivitis and with or without asthma. METHODS: In this phase 1, multicenter, double-blinded, randomized trial (NCT01678807), children received placebo, HDM SLIT tablet 6 standardized quality (SQ) HDM, or 12 SQ-HDM once daily for 28 days. The primary end point was the proportion of subjects with treatment-emergent AEs receiving active treatment vs placebo. The secondary end point was the proportion of subjects who discontinued owing to AEs. RESULTS: In total 195 subjects were randomized. The 2 HDM SLIT tablet doses were well tolerated. No anaphylactic reactions, systemic allergic reactions, AEs requiring epinephrine, serious AEs, or local swellings in the mouth or throat assessed as severe were reported. The proportion of subjects with treatment-emergent AEs was 54% with 6 SQ-HDM and 57% with 12 SQ-HDM (nonsignificant vs 43% with placebo). Local AEs were the most commonly reported treatment-emergent AEs. On day 1, the median duration of individual local AEs ranged from 1 to 43 minutes. The proportion of subjects who discontinued owing to AEs was 0%, 6.2%, and 6.2%, and who experienced treatment-related AEs was 25%, 45%, and 52% for the placebo, 6 SQ-HDM, and 12 SQ-HDM groups, respectively. CONCLUSION: The 6 and 12 SQ-HDM doses of the HDM SLIT tablet MK-8237 were well tolerated, and local AEs were of short duration. TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT01678807.

Onset and dose-related efficacy of house dust mite sublingual immunotherapy tablets in an environmental exposure chamber.

BACKGROUND: The magnitude of effect of sublingual immunotherapy for house dust mite (HDM)-induced allergic rhinitis with or without conjunctivitis is uncertain, partly because there are few well-controlled trials with well-defined doses. OBJECTIVE: We sought to determine the dose-related efficacy and onset of action of the HDM sublingual immunotherapy tablet MK-8237 (Merck/ALK-Abelló) using the Vienna Challenge Chamber. METHODS: In this randomized, double-blind, single-site trial, adults with HDM-induced allergic rhinitis with or without conjunctivitis and with or without asthma (n = 124) received 12 developmental units (DU) of MK-8237, 6 DU of MK-8237, or placebo daily for 24 weeks. Subjects underwent 6-hour exposure challenges at screening and weeks 8, 16, and 24. The total nasal symptom score (TNSS) during chamber challenge at week 24 was the primary end point. The TNSS was the sum of 4 nasal symptom scores (maximum = 12). Total ocular symptom scores (TOSSs; 2 symptoms; maximum = 6) and total symptom scores (TSSs; TSS = TNSS plus TOSS; maximum = 18) were secondary end points. RESULTS: Dose- and time-dependent improvements with MK-8237 versus placebo were observed. At week 24, TNSS improvement relative to placebo was 48.6% (95% CI, 35.3% to 60.2%) with 12 DU of MK-8237 and 26.6% (95% CI, 11.2% to 39.6%) with 6 DU of MK-8237. Statistically significant improvements for TNSSs were also observed at weeks 8 (12 DU of MK-8237) and 16 (6 and 12 DU of MK-8237) and for TOSSs and TSSs by both doses at week 24. MK-8237 was well tolerated. No investigator-assessed anaphylactic allergic reactions or reactions requiring epinephrine were observed. CONCLUSIONS: MK-8237, 12 DU, reduced nasal and ocular symptoms and exceeded World Allergy Organization-established clinical efficacy criteria (≥20% improvement vs placebo). The onset of action for 12 DU of MK-8237 was week 8. MK-8237, 12 DU, is appropriate for further evaluation to determine the magnitude of effect in an uncontrolled allergen exposure environment.

Timothy specific IgE levels are associated with efficacy and safety of timothy grass sublingual immunotherapy tablet.

BACKGROUND: Regional pollen allergen exposure differences may induce variable sensitization profiles that could affect allergen immunotherapy efficacy and safety. OBJECTIVE: To describe sensitization profiles against timothy grass allergen components (Phl p) in North American subjects screened for a timothy grass sublingual immunotherapy (SLIT) tablet trial and evaluate grass SLIT tablet efficacy and safety based on pretreatment Phl p IgE levels. METHODS: Serum-specific IgE was measured post hoc by ImmunoCAP ISAC from subjects screened (N = 1,905) for study P08067 (NCT01385371) conducted in Canada and 5 US regions. Subjects exhibited positivity for timothy grass by skin prick testing and serum IgE. Average total combined symptom plus medication score during the entire pollen season and treatment-related adverse events (TRAEs) were determined in randomized subjects (n = 1,140) by pretreatment Phl p IgE levels (group 1, ≤33rd percentile; group 2, >33rd-67th percentile; group 3, >67th percentile; or undetectable). RESULTS: Most screened subjects were sensitized to Phl p 1 (73%) and Phl p 5 (51%). The highest mean IgE levels and largest proportions of subjects with positive reactions for Phl p 1 and Phl p 5 were found in Canada and the western United States. Improvements in total combined symptom plus medication score vs placebo by Phl p 5 IgE groups 1 to 3 were 7.7%, 23.9%, and 35.4%, respectively, and 18.7% for subjects with undetectable Phl p 5 IgE. TRAE incidences with the grass SLIT tablet by Phl p 5 IgE groups 1 to 3 were 56.1%, 66.4%, and 74.5%, respectively, and 49.7% in subjects with undetectable Phl p 5 IgE. Similar, but less pronounced, trends for efficacy and TRAEs were observed for Phl p 1 and Phl p 6 IgE. CONCLUSION: Sensitization profiles varied by region. Trends toward higher efficacy and increased TRAE incidence in subjects with higher pretreatment Phl p IgE levels were observed. TRIAL REGISTRY: www.clinicaltrials.gov, identifier NCT01385371.

Safety and tolerability of a short ragweed sublingual immunotherapy tablet.

BACKGROUND: MK-3641 is a short ragweed sublingual tablet under investigation for immunotherapy of ragweed pollen-induced allergic rhinitis. OBJECTIVE: To characterize the safety and tolerability of a ragweed sublingual tablet (Merck/ALK-Abelló) in ragweed-allergic adults with or without conjunctivitis. METHODS: Data from 4 randomized, double-blinded, placebo-controlled trials of MK-3641 (2 28-day and 2 52-week trials) were evaluated. Pooled analyses examined short-term safety over 28 days from all 4 trials and long-term safety from the 52-week trials. RESULTS: Across all studies, 757, 198, 454, and 1,058 subjects were randomized to placebo or 1.5, 6, or 12 Amb a 1-U of MK-3641, respectively. Treatment-related adverse events were more frequent in the 6- and 12-Amb a 1-U MK-3641 groups than in the placebo group and were primarily local application-site reactions occurring in the first few days of treatment. There was no treatment-associated loss of asthma control or worsening of asthma associated with treatment. No swellings led to airway obstruction or respiratory compromise. No treatment-related anaphylactic shock, life-threatening, or serious treatment-related adverse events were reported for any MK-3641 dose. Of the 1,707 MK-3641-treated subjects, 1 systemic (anaphylactic) reaction was reported (0.06%). The 52-week long-term assessment was generally similar to the safety profile based on the 28-day assessment. CONCLUSION: MK-3641 doses up to and including 12 Amb a 1-U were well tolerated, with no unexpected safety findings. Sublingual immunotherapy risks such as worsening asthma or airway swellings that could cause airway obstruction were not observed. Systemic reactions and use of epinephrine were uncommon. In these studies, after the first dose was administered in a health care setting, self-administration was well tolerated. TRIAL REGISTRATION: clinicaltrials.gov Identifiers: NCT01469182, NCT00783198, NCT00770315, and NCT00978029.