A/H5N1 prepandemic influenza vaccine (whole virion, vero cell-derived, inactivated) [Vepacel®

The influenza A subtype H5N1 virus is a likely causative agent for the next human influenza pandemic. Pandemic influenza vaccine production can begin only after a novel pandemic virus emerges. Cell-based vaccine production has advantages over conventional egg-based methods, allowing more rapid large-scale vaccine production. A reliable Vero cell culture system is available for pandemic and prepandemic influenza vaccine production. Prepandemic influenza vaccines are an important component of influenza pandemic preparedness plans, as their targeted use in the pandemic alert period or early in a pandemic is likely to mitigate the consequences of an influenza outbreak. Vepacel? is a prepandemic influenza vaccine (whole virion, Vero cell-derived, inactivated) containing antigen of H5N1 strain A/Vietnam/1203/2004 and is approved for use in the EU. Clinical immunogenicity studies with the vaccine have demonstrated good rates of functional neutralizing antibody responses against the vaccine strain (A/Vietnam/1203/2004), meeting established immunogenicity criteria for seasonal influenza vaccines, and cross-reactivity against H5N1 strains from other clades. In phase I/II and III studies, a heterologous (A/Indonesia/05/2005) booster vaccine administered to healthy adult and elderly volunteers 6-24 months after the two-dose priming vaccine (A/Vietnam/1203/2004) regimen induced good immunogenic responses against both H5N1 strains, demonstrating strong immunological memory. Broadly similar, albeit less robust, responses were observed in two special risk cohorts of immunocompromised and chronically ill patients. In general, adverse events observed in clinical immunogenicity studies with H5N1 vaccine (A/Vietnam/1203/2004) were similar to those reported with non-adjuvanted, inactivated, seasonal influenza vaccines.     

Cross clade prophylactic and therapeutic efficacy of polyvalent equine immunoglobulin F(ab′)2 against highly pathogenic avian influenza H5N1 in mice

BackgroundHighly pathogenic avian influenza H5N1 virus (HPAI H5N1) has the potential to cause a new pandemic, which may lead to disasters in the world. However, we cannot predict the HPAI H5N1 strain that might cause the pandemic. Therefore, broad-spectrum prophylactic or therapeutic preparations for containment of a possible future pandemic are urgently needed. Polyvalent equine immunoglobulin F(ab′)2 may be a promising candidate.MethodsWe prepared four pepsin digested immunoglobulin F(ab′)2 from the horses immunized with purified VNH5N1-Puerto Rico/8/34 (PR8)/CDC-RG (VNRG, Clade 1), A/Indonesia/05/2005(H5N1)-PR8-IBCDC-RG2 (INRG, Clade 2.1), and A/Anhui/01/2005(H5N1)-PR8-IBCDC-RG5 (AHRG, Clade 2.3.4) and PBS (negative control), respectively. The protective effect of the monovalent or polyvalent F(ab′)2 against A/Ostrich/SZ/097/04 (clade 0) infection was determined by cytopathic effect (CPE) in cultured Madin–Darby canine kidney (MDCK) cells. The prophylactic and therapeutic efficacy of the polyvalent F(ab′)2 was further evaluated by observing survival, weight loss and viral load when the polyvalent F(ab′)2 was introduced into mice one day prior to-, three days post-lethal challenge with A/Ostrich/SZ/097/04.ResultsThe half neutralization doses (ND50) of purified monovalent equine F(ab′)2 prepared by the VNRG, INRG or AHRG-immunized horses and polyvalent one against A/Ostrich/SZ/097/04 were 320, 1280, 1280 and 2560 in cultured MDCK cells, respectively. 10 μg polyvalent F(ab′)2 could completely protect mice infected with 100 half lethal doses (LD50) of A/Ostrich/SZ/097/04 in preventive settings. In therapeutic settings, even when injected three days post lethal infection, mice were still completely protected, although 200 μg of polyvalent F(ab′)2 was required.ConclusionsOur work has provided experimental supports for testing the broad-spectrum protective efficacy of polyvalent equine immunoglobulin F(ab′)2 for the future large trials.     

Persistence of immune responses after a single dose of Novartis meningococcal serogroup A, C, W-135 and Y CRM-197 conjugate vaccine (Menveo®) or Menactra® among healthy adolescents

The persistence of human bactericidal activity (hSBA) responses in adolescents was assessed 22 months after vaccination with one dose of Menveo? (MenACWY-CRM; Novartis) or Menactra? (MCV4) (sanofi pasteur). The proportion of subjects with hSBA titers ≥8 was significantly higher among recipients of MenACWY-CRM than MCV4 for serogroups A, W-135 and Y.     

Efficacy of the pentavalent rotavirus vaccine, RotaTeq® (RV5), between doses of a 3-dose series and with less than 3 doses (incomplete regimen)

Post-hoc analyses of the Rotavirus Efficacy and Safety Trial (REST) were conducted to determine whether the pentavalent rotavirus vaccine (RV5) confers early protection against rotavirus gastroenteritis (RVGE) before completion of the 3-dose regimen. To evaluate the efficacy of RV5 between doses in reducing the rates of RVGE-related hospitalizations and emergency department (ED) visits in infants who ultimately received all 3 doses of RV5/placebo, events occurring from 2 weeks after the first and second doses to receipt of the subsequent dose (Analysis A) and events occurring from 2 weeks after the first and second doses to 2 weeks after the subsequent dose (Analysis B) were analyzed. In Analysis A, RV5 reduced the rates of combined hospitalizations and ED visits for G1-G4 RVGE or RVGE regardless of serotype between doses 1 and 2 by 100% (95% confidence interval [CI]: 72-100%) or 82% (95% CI: 39-97%), respectively, and between doses 2 and 3, RV5 reduced the rates of combined hospitalizations and ED visits for G1-G4 RVGE or RVGE regardless of serotype by 91% (95% CI: 63-99%) or 84% (95% CI: 54-96%), respectively. Similar rate reductions were observed in Analysis B. These data suggest that RV5 provides a high level of protection between doses against hospitalizations and ED visits for RVGE starting as early as 14 days after the first dose.     

Adherence to,and effectiveness of,subcutaneous interferon β-1a administered by RebiSmart® in patients with relapsing multiple sclerosis: results of the 1-year,observational SMART study

Background: Patients with multiple sclerosis who have poor adherence to treatment have a higher risk of relapse than adherent patients. This study assessed adherence to, and effectiveness and convenience of, treatment with subcutaneous (sc) interferon (IFN) β-1a (Rebif®, Merck Serono SA) 44 or 22 μg three times weekly in patients with relapsing multiple sclerosis (RMS) using the RebiSmart® electronic, multidose, autoinjector for 1 year.

Study design: European, multicentre, observational study among neurologists: inclusion criteria included RMS, Expanded Disability Status Scale score ≤ 6, sc IFN β-1a administered by RebiSmart for ≤ 6 weeks. The primary endpoint was cumulative adherence recorded by RebiSmart.

Results: The safety population included 912 patients, 77.4% (n = 823) of whom completed the Month-12 visit. Mean (± standard deviation) cumulative adherence was 97.1 ± 7.3% (n = 791). The most common reason for missed injection was ‘forgot to inject’ (37.0%). At Month 12/ED, 79.5% of patients were relapse-free. Of 353 patients who rated the convenience of the device, 68.3% found injecting ‘very easy’. No unknown safety issues were detected.

Conclusions: Patients with RMS self-injecting sc IFN β-1a with RebiSmart had excellent adherence at Month 12/ED, which was associated with good clinical outcomes and no unexpected safety issues. Patients rated RebiSmart as convenient and easy to use.     

Stimulation of adenylate cyclase of guinea pig gastric mucosa by histamine,sodium fluoride and 5′-guanylylimidodiphosphate and inhibition by histamine H1- and H2-receptor antagonists in vitro

Summary There are experimental data indicating that cyclic AMP is involved in the regulation of gastric acid secretion in various mammalian species. In a broken cell preparation of guinea pig gastric mucosa the effects of some stimulants of gastric acid secretion on the activity of adenylate cyclase were studied. The basal adenylate cyclase activity was 483±43 pmoles cyclic AMP/mg proteinx10 min. The activity could be stimulated by histamine maximally 5-fold, by sodium fluoride (NaF) maximally 20-fold and by 5-guanylylimidodiphosphate (GMP-PNP) maximally 10-fold. Neither pentagastrin nor carbachol were able to stimulate the adenylate cyclase. Stimulants of adrenergic - or -receptors (phenylephrine, isoproterenol) were also ineffective.The activation of the adenylate cyclase by histamine was inhibited by the histamine H₁-receptor antagonists diphenhydramine and mepyramine as well as by the histamine H₂-receptor antagonist metiamide. On the other hand, the stimulatory action of NaF or GMP-PNP could be antagonized only by high concentrations of dipenhydramine or mepyramine while metiamide showed no antagonizing effect in this respect. Thus this preparation can be used as a tool to determine the activity and specificity of histamine H₂-receptor antagonists.     

Methyl-β-cyclodextrin induces programmed cell death in chronic myeloid leukemia cells and, combined with imatinib, produces a synergistic downregulation of ERK/SPK1 signaling

Lipid rafts mediate several survival signals in the development of chronic myeloid leukemia (CML). Methyl-β-cyclodextrin (MβCD) is an inhibitor specifically designed to disrupt lipid rafts in cells by depleting the cholesterol component. We hypothesize that treatment of CML cells with MβCD and imatinib could reduce imatinib resistance. Apoptotic and autophagic cell death was assayed using annexin V-propidium iodide double staining, immunoblotting, and immunocytochemistry. We next investigated whether MβCD could enhance the cytotoxicity of imatinib in imatinib-sensitive and imatinib-resistant K562 cells. Extracellular signal-regulated kinase/sphingosine kinase 1 signaling downstream of lipid raft-activated signaling pathways was significantly inhibited by treatment of cells with a combination of MβCD and imatinib compared with treatment with either agent alone. MβCD induces programmed cell death in CML cells, and its antileukemia action is synergistic with that of imatinib.     

A phase I safety and dose escalation trial of docetaxel combined with GEM®231, a second generation antisense oligonucleotide targeting protein kinase A R1α in patients with advanced solid cancers

Summary Purpose: GEM?231 is a second-generation antisense oligonucleotide targeting the mRNA of the R1α regulatory subunit of cAMP dependent protein kinase A. Preclinical studies have demonstrated synergistic antitumor activity when GEM?231 is combined with docetaxel. This trial assesses the safety of this combination. Experimental Design: Docetaxel was administered once every three weeks (one-cycle) at doses between 50–75 mg/m². GEM?231 was administered twice weekly at 220 mg/m² for 3 (schedule-A), or 2 (schedule-B) weeks. Results: Twenty patients with chemotherapy-refractory advanced cancer received a total of 39 cycles of therapy. Six patients in schedule-A received docetaxel 50 mg/m², and 14 patients in schedule-B received docetaxel 50–75 mg/m². In schedule-A, 2 of 6 patients developed cycle-1 dose limiting toxicity (DLT)-grade-3 fatigue or grade-3 serum transaminase elevation. In schedule-B, 1 of 4 patients developed cycle-1 DLT at the highest dose of docetaxel tested (75 mg/m²)—grade–3 febrile neutropenia. Subsequent dose escalations were not pursued since the overall incidence of grade-3 toxicities (including those that occurred after cycle 1) was 75%, and this dose was close to the single agent MTD of docetaxel. Grade-3 toxicities included fatigue (2 patients), transaminase elevation (4 patients), and altered mentation (1 patient). The mean post-infusion aPTT was significantly higher than the pre-infusion value [14.8 seconds; p<0.001]; however, there were no hemorrhagic episodes. Conclusions: The recommended dose for further development of the combination of docetaxel and GEM?231 is 75 mg/m² and 220 mg/m², respectively. It is important to administer GEM?231 twice weekly for 2 consecutive weeks followed by a one-week break. This study was supported by grants from Hybridon, Inc. and Aventis Pharmaceuticals.     

Selective role for tumor necrosis factor-α, but not interleukin-1 or Kupffer cells, in down-regulation of CYP3A11 and CYP3A25 in livers of mice infected with a noninvasive intestinal pathogen

Hepatic cytochrome P450 (P450) gene and protein expression are modulated during inflammation and infection. Oral infection of C57BL/6 mice with Citrobacter rodentium produces mild clinical symptoms while selectively regulating hepatic P450 expression and elevating levels of proinflammatory cytokines. Here, we explored the role of cytokines in the regulation of hepatic P450 expression by orally infecting tumor necrosis factor-α (TNFα) receptor 1 null mice (TNFR1−/−), interleukin-1 (IL1) receptor null mice (IL1R1−/−), and Kupffer cell depleted mice with C. rodentium. CYP4A mRNA and protein levels and flavin monooxygenase (FMO)3 mRNA expression levels were down-regulated, while CYP2D9 and CYP4F18 mRNAs remained elevated during infection in wild-type, receptor knockout, and Kupffer cell depleted mice. CYPs 3A11 and 3A25 mRNA levels were down-regulated during infection in wild-type mice but not in TNFR1−/− mice. Consistent with this observation, CYPs 3A11 and 3A25 were potently down-regulated in mouse hepatocytes treated with TNFα. Oral infection of IL1R1−/− mice and studies with mouse hepatocytes indicated that IL1 does not directly regulate CYP3A11 or CYP3A25 expression. Uninfected mice injected with clodronate liposomes had a significantly reduced number of Kupffer cells in their livers. Infection increased the Kupffer cell count, which was attenuated by clodronate treatment. The P450 mRNA and cytokine levels in infected Kupffer cell depleted mice were comparable to those in infected mice receiving no clodronate. The results indicate that TNFα is involved in the regulation of CYPs 3A11 and 3A25, but IL1β and Kupffer cells may not be relevant to hepatic P450 regulation in oral C. rodentium infection.     

Identification of 5-HT2 receptors, α1-adrenoceptors and amine release sites in rat brain by autoradiography with [125I]7-amino-8-iodo-ketanserin

Using autoradiographical techniques, we found that [¹²⁵I]7-amino-8-iodo-ketanserin ([¹²⁵I]AMIK) labelled with high affinity 5-HT₂ receptors, α₁-adrenoceptors and sites involved in the release of biogenic amines and metabolites. The three binding sites for [¹²⁵I]AMIK were identified by using selective inhibitors, i.e. BW 501 for 5-HT₂ receptors, prazosin for α₁-adrenoceptors and tetrabenazine for the sites involved in the release of biogenic amines and metabolites. Using quantitative image analysis, we calculated the inhibition curves for the drugs in areas containing one of the receptor binding sites, i.e. the claustrum for 5-HT₂ receptors, the thalamic nuclei for the α₁-adrenoceptors and the rostral part of the caudate putamen for the release sites. By using appropriate combinations of [¹²⁵I]AMIK and drugs to occlude other binding sites, we could selectively label 5-HT₂ receptors (in the presence of 0.1 μM prazosin and 1 μM tetrabenazine), α₁-adrenoceptors (in the presence of 1 μM BW 501 and 1 μM tetrabenazine) and release sites (in the presence 0.1 μM prazosin and 1 μM BW 501). Most binding to 5-HT₂ receptors was observed in the cortical areas, the caudal caudate-putamen and the substantia nigra, while moderate binding was noticed in the nucleus accumbens, the olfactory bulb and the olfactory tubercle. There were many α₁-adrenoceptors in the numerous thalamic nuclei and few in the cortical areas, the periaquaductal grey matter and the substantia nigra. The sites involved in the release of biogenic amines and metabolites were abundant in the caudate-putamen and there were fewer of these sites in the olfactory tubercle, the nucleus accumbens and in the periaquaductal grey matter.