Respiratory Syncytial Virus (RSV) causes lower respiratory tract infections that can be severe and sometimes fatal. The risk for severe RSV infection is highest in infants and older adults. A safe ...and effective RSV vaccine for older adults represents a serious unmet medical need due to higher morbidity and mortality in this age group. In this randomized, partially double-blind, placebo-controlled, phase 1 dose-escalation study, we evaluated the safety, tolerability and immunogenicity of an investigational messenger ribonucleic acid (mRNA) vaccine encoding the RSV fusion protein (F) stabilized in the prefusion conformation. The study was conducted in healthy younger adults (ages ≥18 and ≤49 years) and healthy older adults (ages ≥60 and ≤79 years). Participants received mRNA-1777 (V171) or placebo as a single intramuscular dose. For each dose level, three sentinel participants were administered open-label mRNA-1777 (V171). Seventy-two younger adults were randomized and administered 25, 100, or 200 µg mRNA-1777 (V171) or placebo, and 107 older adults were randomized and administered 25, 100, 200 or 300 µg mRNA-1777 (V171) or placebo. Primary objectives were safety and tolerability and secondary objectives included humoral and cell-mediated immunogenicity. All dose levels of mRNA-1777 (V171) were generally well tolerated and no serious adverse events related to the vaccine were reported. Immunization with mRNA-1777 (V171) elicited a humoral immune response as measured by increases in RSV neutralizing antibody titers, serum antibody titers to RSV prefusion F protein, D25 competing antibody titers to RSV prefusion F protein, and cell-mediated immune responses to RSV-F peptides.
Omarigliptin is a once-weekly (q.w.) oral DPP-4 inhibitor that is approved for the treatment of patients with type 2 diabetes mellitus (T2DM) in Japan. To support approval of omarigliptin in the ...United States, the clinical development program included a cardiovascular (CV) safety study. Subsequently, a business decision was made not to submit a marketing application for omarigliptin in the United States, and the CV safety study was terminated. Herein we report an analysis of data from that early-terminated study.
In this randomized, double-blind study, 4202 patients with T2DM and established CV disease were assigned to either omarigliptin 25 mg q.w. or matching placebo in addition to their existing diabetes therapy. A Cox proportional hazards model was used to summarize the primary endpoint of time to first major adverse CV event (MACE, the composite of CV death, nonfatal myocardial infarction, and nonfatal stroke) and the analysis of first event of hospitalization for heart failure (hHF).
The median follow-up was approximately 96 weeks (range 1.1-178.6 weeks). The primary MACE outcome occurred in 114/2092 patients in the omarigliptin group (5.45%; 2.96/100 patient-years) and 114/2100 patients in the placebo group (5.43%; 2.97/100 patient-years), with a hazard ratio (HR) of 1.00 (95% confidence interval CI 0.77, 1.29). The hHF outcome occurred in 20/2092 patients in the omarigliptin group (0.96%; 0.51/100 patient-years) and 33/2100 patients in the placebo group (1.57%; 0.85/100 patient-years), with an HR of 0.60 (95% CI 0.35, 1.05). After 142 weeks, the least-squares mean difference (omarigliptin vs. placebo) in glycated hemoglobin levels was -0.3% (95% CI -0.46, -0.14). The numbers of patients with adverse events, serious adverse events or discontinued from study medication due to adverse events were similar in the omarigliptin and placebo groups.
In this CV safety study of patients with T2DM and established CV disease, omarigliptin did not increase the risk of MACE or hHF and was generally well tolerated. Trial registration ClinicalTrials.gov: NCT01703208. Registered 05 October 2012.
Foxg1 Suppresses Early Cortical Cell Fate Hanashima, Carina; Li, Suzanne C.; Shen, Lijian ...
Science (American Association for the Advancement of Science),
01/2004, Letnik:
303, Številka:
5654
Journal Article
Recenzirano
During mammalian cerebral corticogenesis, progenitor cells become progressively restricted in the types of neurons they can produce. The molecular mechanism that determines earlier versus later born ...neuron fate is unknown. We demonstrate here that the generation of the earliest born neurons, the Cajal-Retzius cells, is suppressed by the telencephalic transcription factor Foxg1. In Foxg1 null mutants, we observed an excess of Cajal-Retzius neuron production in the cortex. By conditionally inactivating Foxg1 in cortical progenitors that normally produce deep-layer cortical neurons, we demonstrate that Foxg1 is constitutively required to suppress Cajal-Retzius cell fate. Hence, the competence to generate the earliest born neurons during later cortical development is actively suppressed but not lost.
Nicotinic acid (NA) is commonly used to treat dyslipidemia, but it elicits an adverse effect, termed flushing, which consists of cutaneous vasodilation with associated discomfort. An animal model of ...NA-induced flushing has been established in mice. As in humans, NA stimulated vasodilation in a dose-dependent manner, was associated with an increase of the vasodilatory prostaglandin (PG) D₂ in plasma and could be blocked by pretreatment with aspirin. Two PGD₂ receptors have been identified: PGD₂ receptor 1 (DP1, also called DP) and PGD2 receptor 2 (DP2, sometimes termed CRTH2). DP2 does not mediate NA-induced vasodilation; the DP2specific agonist DK-PGD₂ (13,14-dihydro-15-keto-PGD₂) did not induce cutaneous vasodilation, and$DP2^{-/-}$mice had a normal vasodilatory response to NA. By contrast, BW245C, a DPi-selective agonist, induced vasodilation in mice, and MK-0524, a DPl-selective antagonist, blocked both PGD₂-and NA-induced vasodilation. NA-induced vasodilation was also studied in$DP1^{+/+}$,$DP^{+/-}$, and$DP1^{-/-}$mice; although NA-induced vasodilation depended almost completely on DP1 in female mice, it depended only partially on DP1 in male mice. The residual NA-induced vasodilation in male$DP^{-/-}$mice was aspirin-sensitive. Thus, in the mouse, DP1 appears to be an important component involved in NA-induced vasodilation, but other cyclooxygenase-dependent mechanisms also may be involved. A clinical study in healthy men and women demonstrated that treatment with MK-0524 reduced the symptoms of flushing and the increase in skin perfusion after the administration of NA. These studies suggest that DP1 receptor antagonism may be an effective means to suppress NA-induced flushing in humans.
Background Prostaglandin D2 is a proinflammatory mediator believed to be important in asthma and allergic rhinitis (AR). Allelic variants in the prostaglandin D2 receptor type 1 (DP1) gene (PTGDR) ...have been suggested to be associated with asthma susceptibility. Objectives We sought to investigate the efficacy of the DP1 antagonist laropiprant (alone or with montelukast) in asthma and seasonal AR and explore whether sequence variations in PTGDR are associated with asthma severity. Methods For asthma, in a double-blind crossover study, 100 patients with persistent asthma were randomized to placebo or laropiprant, 300 mg/d for 3 weeks, followed by addition of montelukast, 10 mg/d for 2 weeks. PTGDR promoter haplotypes were categorized as high, medium, or low transcriptional efficiency. The primary efficacy end point was FEV1 . For AR, in a double-blind parallel-group study, 767 patients sensitized to a regionally prevalent fall allergen with symptomatic fall rhinitis were allocated to laropiprant, 25 mg/d or 100 mg/d; cetirizine, 10mg/d; or placebo for 2 weeks. The primary end point was the Daytime Nasal Symptoms Score. Results For asthma, no significant differences in FEV1 or asthma symptoms were noted for laropiprant versus placebo or laropiprant plus montelukast vs montelukast (differences between montelukast and placebo: P ≤ .001). No clear association was seen between haplotype pair (ie, diplotype) and asthma severity. For AR, although cetirizine (vs placebo) demonstrated an improvement in the Daytime Nasal Symptoms Score ( P < .001), laropiprant did not. Conclusion Laropiprant did not demonstrate efficacy in asthmatic patients or patients with AR. Variations in PTGDR did not appear related to baseline asthma severity or treatment response (NCT00533208; NCT00783601).
Niacin (nicotinic acid) is not optimally used mainly because of flushing, a process mediated primarily by prostaglandin D2 , which leads to poor patient compliance and suboptimal dosing. This phase ...II dose-ranging study was designed to assess whether the prostaglandin D2 receptor 1 antagonist laropiprant (LRPT; MK-0524) would (1) reduce extended-release niacin (ERN)–induced flushing in dyslipidemic patients and (2) support a novel accelerated ERN dosing paradigm: initiating ERN at 1 g and advancing rapidly to 2 g. In part A of the study, 154 dyslipidemic patients were randomized to LRPT 150 mg/day or placebo in a 9-week, 2-period crossover study. Patients who completed part A (n = 122) entered part B (after a 2-week washout), together with additional patients who entered part B directly (n = 290). Part B patients were randomized to placebo, ERN 1 g (Niaspan, no previous titration), or ERN 1 g coadministered with LRPT 18.75, 37.5, 75, or 150 mg for 4 weeks, with doubling of the respective doses for the remaining 4 weeks. Patients treated with LRPT plus ERN experienced significantly less ERN-induced flushing than those treated with ERN alone during the initiation of treatment (ERN 1 g, week 1) and the maintenance treatment (ERN 1 to 2 g, weeks 2 to 8). All doses of LRPT were maximally effective in inhibiting niacin-induced flushing. LRPT did not alter the beneficial lipid effects of ERN. LRPT plus ERN was well tolerated. In conclusion, the significant reduction in ERN-induced flushing provided by LRPT plus ERN supports an accelerated ERN dose-advancement paradigm to achieve rapidly a 2-g dose in dyslipidemic patients.
We report on the safety and immunogenicity of V591, a measles vector-based SARS-CoV-2 vaccine candidate.
In this multicentre, randomised, placebo-controlled, double-blind, phase 1/2 trial, healthy ...adults with no history of COVID-19 disease were assigned to intramuscular injection of V591 or placebo (4:1 ratio). In part 1, younger adults (18-55 years) received V591 median tissue culture infectious dose (TCID50)-levels of 1×105 or 1×106 or placebo, 56 days apart. In part 2, younger and older (>55 years) adults received a single dose of one of four (104/105/106/107) or one of two (105/106) V591 TCID50 levels, respectively, or placebo. Primary outcome: safety/tolerability. Secondary outcome: humoral immunogenicity. ClinicalTrials.gov: NCT04498247.
From August–December 2020, 444 participants were screened and 263 randomised (210 V591; 53 placebo); 262 received at least one and 10 received two doses of V591 or placebo. Adverse events were experienced by 140/209 (67.0%) V591 dose-group participants and 37/53 (69.8%) placebo-group participants following injection 1; most frequent were fatigue (57 27.3% vs 20 37.7%), headache (57 27.3% vs 19 35.8%), myalgia (35 16.7% vs 10 18.9%), and injection-site pain (35 16.7% vs 4 7.5%). No deaths nor vaccine-related serious adverse events occurred. At Day 29, no anti-SARS-CoV-2 spike serum neutralising antibody and IgG-responses were identified in placebo or the three lower V591 dose-groups; responses were detected with V591 1×107 TCID50, although titres were lower than convalescent serum.
V591 was generally well tolerated, but immunogenicity was insufficient to warrant continued development.
Merck Sharp & Dohme, Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA.
Neutralizing mAbs can prevent communicable viral diseases. MK-1654 is a respiratory syncytial virus (RSV) F glycoprotein neutralizing monoclonal antibody (mAb) under development to prevent RSV ...infection in infants. Development and validation of methods to predict efficacious doses of neutralizing antibodies across patient populations exposed to a time-varying force of infection (i.e., seasonal variation) are necessary.
Five decades of clinical trial literature were leveraged to build a model-based meta-analysis (MBMA) describing the relationship between RSV serum neutralizing activity (SNA) and clinical endpoints. The MBMA was validated by backward translation to animal challenge experiments and forward translation to predict results of a recent RSV mAb trial. MBMA predictions were evaluated against a human trial of 70 participants who received either placebo or one of four dose-levels of MK-1654 and were challenged with RSV NCT04086472. The MBMA was used to perform clinical trial simulations and predict efficacy of MK-1654 in the infant target population.
The MBMA established a quantitative relationship between RSV SNA and clinical endpoints. This relationship was quantitatively consistent with animal model challenge experiments and results of a recently published clinical trial. Additionally, SNA elicited by increasing doses of MK-1654 in humans reduced RSV symptomatic infection rates with a quantitative relationship that approximated the MBMA. The MBMA indicated a high probability that a single dose of ≥ 75 mg of MK-1654 will result in prophylactic efficacy (> 75% for 5 months) in infants.
An MBMA approach can predict efficacy of neutralizing antibodies against RSV and potentially other respiratory pathogens.
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