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BackgroundSanfilippo type B is a mucopolysaccharidosis (MPS) with a major neuronopathic component characterized by heparan sulfate (HS) accumulation due to mutations in the NAGLU gene encoding alfa-N-acetyl-glucosaminidase. Enzyme replacement therapy for neuronopathic MPS requires efficient enzyme delivery throughout the brain in order to normalize HS levels, prevent brain atrophy, and potentially delay cognitive decline.MethodsIn this phase I/II open-label study, patients with MPS type IIIB (n = 22) were treated with tralesinidase alfa administered i.c.v. The patients were monitored for drug exposure; total HS and HS nonreducing end (HS-NRE) levels in both cerebrospinal fluid (CSF) and plasma; anti-drug antibody response; brain, spleen, and liver volumes as measured by MRI; and cognitive development as measured by age-equivalent (AEq) scores.ResultsIn the Part 1 dose escalation (30, 100, and 300 mg) phase, a 300 mg dose of tralesinidase alfa was necessary to achieve normalization of HS and HS-NRE levels in the CSF and plasma. In Part 2, 300 mg tralesinidase alfa sustained HS and HS-NRE normalization in the CSF and stabilized cortical gray matter volume (CGMV) over 48 weeks of treatment. Resolution of hepatomegaly and a reduction in spleen volume were observed in most patients. Significant correlations were also established between the change in cognitive AEq score and plasma drug exposure, plasma HS-NRE levels, and CGMV.ConclusionAdministration of tralesinidase alfa i.c.v. effectively normalized HS and HS-NRE levels as a prerequisite for clinical efficacy. Peripheral drug exposure data suggest a role for the glymphatic system in altering tralesinidase alfa efficacy.Trial registrationClinicaltrials.gov NCT02754076.FUNDINGBioMarin Pharmaceutical Inc. and Allievex Corporation.

BACKGROUND. Sanfilippo type B is a mucopolysaccharidosis (MPS) with a major neuronopathic component characterized by heparan sulfate (HS) accumulation due to mutations in the NAGLU gene encoding alfa-N-acetyl-glucosaminidase. Enzyme replacement therapy for neuronopathic MPS requires efficient enzyme delivery throughout the brain in order to normalize HS levels, prevent brain atrophy, and potentially delay cognitive decline. METHODS. In this phase I/II open-label study, patients with MPS type IIIB (n = 22) were treated with tralesinidase alfa administered i.c.v. The patients were monitored for drug exposure; total HS and HS nonreducing end (HS-NRE) levels in both cerebrospinal fluid (CSF) and plasma; anti-drug antibody response; brain, spleen, and liver volumes as measured by MRI; and cognitive development as measured by age-equivalent (AEq) scores. RESULTS. In the Part 1 dose escalation (30, 100, and 300 mg) phase, a 300 mg dose of tralesinidase alfa was necessary to achieve normalization of HS and HS-NRE levels in the CSF and plasma. In Part 2, 300 mg tralesinidase alfa sustained HS and HS-NRE normalization in the CSF and stabilized cortical gray matter volume (CGMV) over 48 weeks of treatment. Resolution of hepatomegaly and a reduction in spleen volume were observed in most patients. Significant correlations were also established between the change in cognitive AEq score and plasma drug exposure, plasma HS-NRE levels, and CGMV. CONCLUSION. Administration of tralesinidase alfa i.c.v. effectively normalized HS and HS-NRE levels as a prerequisite for clinical efficacy. Peripheral drug exposure data suggest a role for the glymphatic system in altering tralesinidase alfa efficacy. TRIAL REGISTRATION. Clinicaltrials.gov NCT02754076. FUNDING. BioMarin Pharmaceutical Inc. and Allievex Corporation., Introduction Lysosomal storage diseases (LSDs) are a family of genetic disorders affecting the breakdown and recycling of complex molecules within the lysosomes (1). The lysosomal compartment contains more than 60 [...]

Background and Purpose: Triptans are 5-HT1B/1D receptor agonists (that also display 5-HT1F receptor affinity) with antimigraine action, contraindicated in patients with coronary artery disease due to their vasoconstrictor properties. Conversely, lasmiditan was developed as an antimigraine 5-HT1F receptor agonist. To assess the selectivity and cardiovascular effects of lasmiditan, we investigated the binding, functional activity, and in vitro/in vivo vascular effects of lasmiditan and compared it to sumatriptan.Experimental Approach: Binding and second messenger activity assays of lasmiditan and other serotoninergic agonists were performed for human 5-HT1A , 5-HT1B , 5-HT1D , 5-ht1E , 5-HT1F , 5-HT2A , 5-HT2B , and 5-HT7 receptors, and the results were correlated with their potency to constrict isolated human coronary arteries (HCAs). Furthermore, concentration-response curves to lasmiditan and sumatriptan were performed in proximal and distal HCA, internal mammary, and middle meningeal arteries. Finally, anaesthetized female beagle dogs received i.v. infusions of lasmiditan or sumatriptan in escalating cumulative doses, and carotid and coronary artery diameters were measured.Key Results: Lasmiditan showed high selectivity for 5-HT1F receptors. Moreover, the functional potency of the analysed compounds to inhibit cAMP increase through 5-HT1B receptor activation positively correlated with their potency to contract HCA. In isolated human arteries, sumatriptan, but not lasmiditan, induced contractions. Likewise, in vivo, sumatriptan decreased coronary and carotid artery diameters at clinically relevant doses, while lasmiditan was devoid of vasoconstrictor activity at all doses tested.Conclusions and Implications: Lasmiditan is a selective 5-HT1F receptor agonist devoid of vasoconstrictor activity. This may represent a cardiovascular safety advantage when compared to the triptans. [ABSTRACT FROM AUTHOR]

Injury causes tissue breakdown, which releases large quantities of intracellular contents into the extracellular space. Some of these materials are well-established activators of the immune system and include heat shock proteins (HSPs), uric acid, nucleotides, High Mobility Group Box-1 protein (HMGB-1), and DNA. Here, we show that in vivo delivery of HSPs into BALB/cJ mice with full-thickness wounds accelerates the rate of wound closure by 60% as compared with control-treated mice. The onset is rapid and the effect is sustained, dose dependent, and protein specific. Adoptive transfer of RAW264 macrophages pretreated with HSP70 into naïve recipients with a wound transfers the HSP-mediated effect on the rate of wound closure. Further, we demonstrate that part of the mechanism by which HSP70 accelerates wound closure is through the stimulation of macrophage-mediated phagocytosis of wound debris. Disabling the HSP70-mediated enhancement of phagocytosis abrogates the HSP-mediated acceleration of the healing process. These findings create two opportunities: one, therapeutic, wherein HSP70 could be used in the clinical management of wounds; and two, pathophysiologic, to decode signals by which the host defenses recognize and respond to injury.

Immunization with high doses of heat shock protein, gp 6 given in vivo, has been shown to mediate the activation of CD4+ T cell, which in turn suppresses an ongoing CD8+ immune response. Here we demonstrate that high doses of gp 6 (HDgp 6) (100 microg given subcutaneously on days 0 and 7 following skin graft transplantation) improve survival of skin grafts with both minor and major histocompatibility. First, skin from male C57BL/6 donors was grafted onto female C57BL/6 recipients that were subsequently treated with either HDgp 6 or buffer and graft survival was monitored. At 64 days post-transplantation, graft recipients treated with HDgp 6 showed 56% graft survival compared to 10% in those treated with buffer. Further, HDgp 6 down regulates a secondary immune response as well. Skin graft obtained from a male C57BL/6 donor was transplanted to a female C57BL/6 recipient that had previously rejected a male skin graft. Recipients that were treated with HDgp 96 showed a 75% graft survival of the secondary graft at 64 days post-transplantation, whereas recipients treated with buffer rejected their secondary grafts within 37 days. Finally, the effect of HDgp 96 treatment on survival of graft with major histoincompatibility was tested. Skin grafts from female BALB/c donors were transplanted to female C57BL/6 recipients previously treated with either HDgp 96 or buffer. Although all the grafts were ultimately rejected, mice treated with HDgp96 showed a delay in the rejection as compared with buffer controls. Our findings indicate that HDgp 96 improves survival of grafts with both minor and major antigenic disparity and could lead to developing novel therapies in transplant medicine.