Search

Background: A SARS-CoV-2 controlled human infection model (CHIM) has been successfully established in seronegative individuals using a dose of 1×10 1 50% tissue culture infectious dose (TCID 50 ) pre-alpha SARS-CoV-2 virus. Given the increasing prevalence of seropositivity to SARS-CoV-2, a CHIM that could be used for vaccine development will need to induce infection in those with pre-existing immunity. Our aim was to find a dose of pre-alpha SARS-CoV-2 virus that induced infection in previously infected individuals., Methods: Healthy, UK volunteers aged 18-30 years, with proven (quantitative RT-PCR or lateral flow antigen test) previous SARS-CoV-2 infection (with or without vaccination) were inoculated intranasally in a stepwise dose escalation CHIM with either 1×10 1 , 1×10 2 , 1×10³, 1×10 4 , or 1×10 5 TCID 50 SARS-CoV-2/human/GBR/484861/2020, the same virus used in the seronegative CHIM. Post-inoculation, volunteers were quarantined in functionally negative pressure rooms (Oxford, UK) for 14 days and until 12-hourly combined oropharyngeal-nasal swabs were negative for viable virus by focus-forming assay. Outpatient follow-up continued for 12 months post-enrolment, with additional visits for those who developed community-acquired SARS-CoV-2 infection. The primary objective was to identify a safe, well tolerated dose that induced infection (defined as two consecutive SARS-CoV-2 positive PCRs starting 24 h after inoculation) in 50% of seropositive volunteers. This study is registered with ClinicalTrials.gov (NCT04864548); enrolment and follow-up to 12 months post-enrolment are complete., Findings: Recruitment commenced on May 6, 2021, with the last volunteer enrolled into the dose escalation cohort on Nov 24, 2022. 36 volunteers were enrolled, with four to eight volunteers inoculated in each dosing group from 1×10 1 to 1×10 5 TCID 50 SARS-CoV-2. All volunteers have completed quarantine, with follow-up to 12 months complete. Despite dose escalation to 1×10 5 TCID 50 , we were unable to induce sustained infection in any volunteers. Five (14%) of 36 volunteers were considered to have transient infection, based on the kinetic of their PCR-positive swabs. Transiently infected volunteers had significantly lower baseline mucosal and systemic SARS-CoV-2-specific antibody titres and significantly lower peripheral IFNγ responses against a CD8 + T-cell SARS-CoV-2 peptide pool than uninfected volunteers. 14 (39%) of 36 volunteers subsequently developed breakthrough infection with the omicron variant after discharge from quarantine. Most adverse events reported by volunteers in quarantine were mild, with fatigue (16 [44%]) and stuffy nose (16 [44%]) being the most common. There were no serious adverse events., Interpretation: Our study demonstrates potent protective immunity induced by homologous vaccination and homologous or heterologous previous SARS-CoV-2 infection. The community breakthrough infections seen with the omicron variant supports the use of newer variants to establish a model with sufficient rate of infection for use in vaccine and therapeutic development., Funding: Wellcome Trust and Department for Health and Social Care., Competing Interests: Declaration of interests MC and SLa are supported by the Oak Foundation. TT, SLo, and SLa are supported by the US Food and Drug Administration Medical Countermeasures Initiative contract 75F40120C00085. VMF acknowledges support from the British Heart Foundation (CH/16/1/32013). AC is a full time paid employee of hVIVO. AJP is chair of the UK Department of Health and Social Care’s (DHSC) Joint Committee on Vaccination and Immunisation, was a member of WHO’s Strategic Advisory Group of Experts until 2022, receives consulting fees from Shionogi, and is in receipt of grants from the UK Medical Research Council, AstraZeneca, Gates Foundation, Wellcome Trust, National Institute for Health and Care Research (NIHR), Serum Institute of India, CEPI, and European Commission through the University of Oxford. AJP, SJ, HMo, SAH, RT, RL-R, and ICP contributed to intellectual property licensed by Oxford University Innovation to AstraZeneca. All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Endocytosis, or internalization through endosomes, is a major cell entry mechanism used by respiratory viruses. Phosphoinositide 5-kinase (PIKfyve) is a critical enzyme for the synthesis of phosphatidylinositol (3, 5)biphosphate (PtdIns (3, 5)P2) and has been implicated in virus trafficking via the endocytic pathway. In fact, antiviral effects of PIKfyve inhibitors against SARS-CoV-2 and Ebola have been reported, but there is little evidence regarding other respiratory viruses. In this study, we demonstrated the antiviral effects of PIKfyve inhibitors on influenza virus and respiratory syncytial virus in vitro and in vivo . PIKfyve inhibitors Apilimod mesylate (AM) and YM201636 concentration-dependently inhibited several influenza strains in an MDCK cell-cytopathic assay. AM also reduced the viral load and cytokine release, while improving the cell integrity of human nasal air-liquid interface cultured epithelium infected with influenza PR8. In PR8-infected mice, AM (2 mg/mL), when intranasally treated, exhibited a significant reduction of viral load and inflammation and inhibited weight loss caused by influenza infection, with effects being similar to oral oseltamivir (10 mg/kg). In addition, AM demonstrated antiviral effects in RSV A2-infected human nasal epithelium in vitro and mouse in vivo , with an equivalent effect to that of ribavirin. AM also showed antiviral effects against human rhinovirus and seasonal coronavirus in vitro . Thus, PIKfyve is found to be involved in influenza and RSV infection, and PIKfyve inhibitor is a promising molecule for a pan-viral approach against respiratory viruses., Competing Interests: J. Baker and H. Ombredane received the research funding from SubIntro Ltd. K. Ito and G. Rapeport were co-founders of SubIntro Ltd. and former consultants of the company. Other authors declare no conflict of interest.

Background: PC786 is a nebulized nonnucleoside respiratory syncytial virus (RSV) polymerase inhibitor designed to treat RSV, which replicates in the superficial layer of epithelial cells lining the airways., Methods: Fifty-six healthy volunteers inoculated with RSV-A (Memphis 37b) were randomly dosed with either nebulized PC786 (5 mg) or placebo, twice daily for 5 days, from either 12 hours after confirmation of RSV infection or 6 days after virus inoculation. Viral load (VL), disease severity, pharmacokinetics, and safety were assessed until discharge. RSV infection was confirmed by reverse-transcription quantitative polymerase chain reaction with any positive value (intention-to-treat infected [ITT-I] population) or RSV RNA ≥1 log10 plaque-forming unit equivalents (PFUe)/mL (specific intention-to-treat infection [ITT-IS] population) in nasal wash samples., Results: In the ITT-I population, the mean VL area under the curve (AUC) was lower in the PC786 group than the placebo group (274.1 vs 406.6 log10 PFUe/mL × hour; P = .0359). PC786 showed a trend toward reduction of symptom score and mucous weight. In ITT-IS (post hoc analysis), the latter was statistically significant as well as VL AUC (P = .0126). PC786 showed an early time to maximum plasma concentration, limited systemic exposure, and long half-life and consequently a 2-fold accumulation over the 5-day dosing period. PC786 was well tolerated., Conclusions: Nebulized PC786 demonstrated a significant antiviral effect against RSV, warranting further clinical study., Clinical Trials Registration: ClinicalTrials.gov: NCT03382431; EudraCT: 2017-002563-18., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America.)

A dramatic global reduction in the incidence of common seasonal respiratory viral infections has resulted from measures to limit the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the pandemic. This has been accompanied by falls reaching 50% internationally in the incidence of acute exacerbations of preexisting chronic respiratory diseases that include asthma, chronic obstructive pulmonary disease, and cystic fibrosis. At the same time, the incidence of acute bacterial pneumonia and sepsis has fallen steeply worldwide. Such findings demonstrate the profound impact of common respiratory viruses on the course of these global illnesses. Reduced transmission of common respiratory bacterial pathogens and their interactions with viruses appear also as central factors. This review summarizes pandemic changes in exacerbation rates of asthma, chronic obstructive pulmonary disease, cystic fibrosis, and pneumonia. We draw attention to the substantial body of knowledge about respiratory virus infections in these conditions, and that it has not yet translated into clinical practice. Now that the large scale of benefits that could be gained by managing these pathogens is unmistakable, we suggest that the field merits substantial academic and industrial investment. We consider how pandemic-inspired measures for prevention and treatment of common infections should become a cornerstone for managing respiratory diseases.

Since its emergence in 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused hundreds of millions of cases and continues to circulate globally. To establish a novel SARS-CoV-2 human challenge model that enables controlled investigation of pathogenesis, correlates of protection and efficacy testing of forthcoming interventions, 36 volunteers aged 18-29 years without evidence of previous infection or vaccination were inoculated with 10 TCID 50 of a wild-type virus (SARS-CoV-2/human/GBR/484861/2020) intranasally in an open-label, non-randomized study (ClinicalTrials.gov identifier NCT04865237 ; funder, UK Vaccine Taskforce). After inoculation, participants were housed in a high-containment quarantine unit, with 24-hour close medical monitoring and full access to higher-level clinical care. The study's primary objective was to identify an inoculum dose that induced well-tolerated infection in more than 50% of participants, with secondary objectives to assess virus and symptom kinetics during infection. All pre-specified primary and secondary objectives were met. Two participants were excluded from the per-protocol analysis owing to seroconversion between screening and inoculation, identified post hoc. Eighteen (~53%) participants became infected, with viral load (VL) rising steeply and peaking at ~5 days after inoculation. Virus was first detected in the throat but rose to significantly higher levels in the nose, peaking at ~8.87 log 10 copies per milliliter (median, 95% confidence interval (8.41, 9.53)). Viable virus was recoverable from the nose up to ~10 days after inoculation, on average. There were no serious adverse events. Mild-to-moderate symptoms were reported by 16 (89%) infected participants, beginning 2-4 days after inoculation, whereas two (11%) participants remained asymptomatic (no reportable symptoms). Anosmia or dysosmia developed more slowly in 15 (83%) participants. No quantitative correlation was noted between VL and symptoms, with high VLs present even in asymptomatic infection. All infected individuals developed serum spike-specific IgG and neutralizing antibodies. Results from lateral flow tests were strongly associated with viable virus, and modeling showed that twice-weekly rapid antigen tests could diagnose infection before 70-80% of viable virus had been generated. Thus, with detailed characterization and safety analysis of this first SARS-CoV-2 human challenge study in young adults, viral kinetics over the course of primary infection with SARS-CoV-2 were established, with implications for public health recommendations and strategies to affect SARS-CoV-2 transmission. Future studies will identify the immune factors associated with protection in those participants who did not develop infection or symptoms and define the effect of prior immunity and viral variation on clinical outcome., (© 2022. The Author(s), under exclusive licence to Springer Nature America, Inc.)

PC945 is a novel antifungal triazole formulated for nebulized delivery to treat lung Aspergillus infections. Pharmacokinetic and safety profiles from nonclinical studies and clinical trials in healthy subjects, and subjects with mild asthma were characterized. Toxicokinetics were assessed following daily 2-hour inhalation for 14 days. Potential for drug-drug interactions was evaluated using pooled human liver microsomes. Clinical safety and pharmacokinetics were assessed following (a) single inhaled doses (0.5-10 mg), (b) 7-day repeat doses (5 mg daily) in healthy subjects; (c) a single dose (5 mg) in subjects with mild asthma. C max occurred 4 hours (rats) or immediately (dogs) after a single dose. PC945 lung concentrations were substantially higher (>2000-fold) than those in plasma. PC945 only inhibited CYP3A4/5 substrate metabolism (IC 50 : 1.33 µM [testosterone] and 0.085 µM [midazolam]). Geometric mean C max was 322 pg/mL (healthy subjects) and 335 pg/mL (subjects with mild asthma) 4-5 hours (median t max ) after a single inhalation (5 mg). Following repeat, once daily inhalation (5 mg), Day 7 C max was 951 pg/mL (0.0016 µM) 45 minutes after dosing. Increases in C max and AUC 0-24h were approximately dose-proportional (0.5-10 mg). PC945 administration was well tolerated in both healthy subjects and subjects with mild asthma. Treatment-emergent adverse events were mild/moderate and resolved before the study ended. No clinically significant lung function changes were observed. PC945 pharmacokinetics translated from nonclinical species to humans showed slow absorption from lungs and low systemic exposure, thereby limiting the potential for adverse side effects and drug interactions commonly seen with systemically delivered azoles., (© 2020 The Authors. Pharmacology Research & Perspectives published by John Wiley & Sons Ltd, British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics.)

Objectives: The growing emergence of azole-resistant Aspergillus fumigatus strains worldwide is a major concern for current systemic antifungal treatment. Here we report antifungal activities of a novel inhaled triazole, PC1244, against a collection of multi-azole-resistant A. fumigatus strains., Methods: MICs of PC1244 were determined for A. fumigatus carrying TR34/L98H (n = 81), TR46/Y121F/T289A (n = 24), M220 (n = 6), G54 (n = 11), TR53 (n = 1), TR463/Y121F/T289A (n = 2), G448S (n = 1), G432C (n = 1) and P216S (n = 1) resistance alleles originating from either India, the Netherlands or France. The effects of PC1244 were confirmed in an in vitro model of the human alveolus and in vivo in temporarily neutropenic, immunocompromised mice., Results: PC1244 exhibited potent inhibition [geometric mean MIC (range), 1.0 mg/L (0.125 to >8 mg/L)] of growth of A. fumigatus strains carrying cyp51A gene mutations, showing much greater potency than voriconazole [15 mg/L (0.5 to >16 mg/L)], and an effect similar to those on other azole-susceptible Aspergillus spp. (Aspergillus flavus, Aspergillus terreus, Aspergillus tubingensis, Aspergillus nidulans, Aspergillus niger, Aspergillus nomius, Aspergillus tamarii) (0.18-1 mg/L). In TR34/L98H and TR46/Y121F/T289A A. fumigatus-infected in vitro human alveolus models, PC1244 achieved superior inhibition (IC50, 0.25 and 0.34 mg/L, respectively) compared with that of voriconazole (IC90, >3 mg/L and >10 mg/L, respectively). In vivo, once-daily intranasal administration of PC1244 (0.56-70 μg/mouse) to the A. fumigatus (AF91 with M220V)-infected mice reduced pulmonary fungal load and serum galactomannan more than intranasal posaconazole., Conclusions: PC1244 has the potential to become a novel topical treatment of azole-resistant pulmonary aspergillosis., (© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.)

Objectives: Management of Candida auris infection is difficult as this yeast exhibits resistance to different classes of antifungals, necessitating the development of new antifungals. The aim of this study was to investigate the susceptibility of C. auris to a novel antifungal triazole, PC945, optimized for topical delivery., Methods: A collection of 50 clinical isolates was obtained from a tertiary care hospital in North India. Nine isolates from the UK, 10 from a CDC panel (USA) and 3 from the CBS-KNAW culture collection (Japanese and South Korean isolates) were also obtained. MICs (azole endpoint) of PC945 and other triazoles were determined in accordance with CLSI M27 (third edition). Quality control strains were included [Candida parapsilosis (ATCC 22019) and Candida krusei (ATCC 6258)]., Results: Seventy-four percent of isolates tested showed reduced susceptibility to fluconazole (≥64 mg/L). PC945 (geometric mean MIC = 0.058 mg/L) was 7.4-fold and 1.5-fold more potent than voriconazole and posaconazole, respectively (both P < 0.01). PC945 MIC values correlated with those of voriconazole or posaconazole, and only three isolates were found to be cross-resistant between PC945 and other azoles. ERG11 sequence analysis revealed several mutations, but no correlation could be established with the MIC of PC945. Tentative epidemiological cut-off values (ECOFFs) evaluated by CLSI's ECOFF Finder (at 99%) with 24 h reading of MICs were 1, 4 and 1 mg/L for PC945, voriconazole and posaconazole, respectively. MIC values for quality control strains of all triazoles were in the normal ranges., Conclusions: PC945 was found to be a more potent inhibitor than posaconazole, voriconazole and fluconazole of C. auris isolates collected globally, warranting further laboratory and clinical evaluations., (© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.)

Invasive pulmonary Aspergillosis is a leading cause of morbidity and mortality in immunosuppressed patients and treatment outcomes using oral antifungal triazoles remain suboptimal. Here we show that combining topical treatment using PC945, a novel inhaled triazole, with systemic treatment using known triazoles demonstrated synergistic antifungal effects against Aspergillus fumigatus (AF) in an in vitro human alveolus bilayer model and in the lungs of neutropenic immunocompromised mice. Combination treatment with apical PC945 and either basolateral posaconazole or voriconazole resulted in a synergistic interaction with potency improved over either compound as a monotherapy against both azole-susceptible and resistant AF invasion in vitro. Surprisingly there was little, or no synergistic interaction observed when apical and basolateral posaconazole or voriconazole were combined. In addition, repeated prophylactic treatment with PC945, but not posaconazole or voriconazole, showed superior effects to single prophylactic dose, suggesting tissue retention and/or accumulation of PC945. Furthermore, in mice infected with AF intranasally, 83% of animals treated with a combination of intranasal PC945 and oral posaconazole survived until day 7, while little protective effects were observed by either compound alone. Thus, the combination of a highly optimised topical triazole with oral triazoles potentially induces synergistic effects against AF infection.

Rationale: Respiratory syncytial virus (RSV) bronchiolitis is a major cause of morbidity and mortality in infancy. Severe disease is believed to result from uncontrolled viral replication, an excessive immune response, or both., Objectives: To determine RSV load and immune mediator levels in nasal mucosal lining fluid by serial sampling of nasal fluids from cases of moderate and severe bronchiolitis over the course of infection., Methods: Infants with viral bronchiolitis necessitating admission (n = 55) were recruited from a pediatric center during 2016 and 2017. Of these, 30 were RSV infected (18 "moderate" and 12 mechanically ventilated "severe"). Nasal fluids were sampled frequently over time using nasosorption devices and nasopharyngeal aspiration. Hierarchical clustering of time-weighted averages was performed to investigate cytokine and chemokine levels, and gene expression profiling was conducted., Measurements and Main Results: Unexpectedly, cases with severe RSV bronchiolitis had lower nasal viral loads and reduced IFN-γ and C-C chemokine ligand 5/RANTES (regulated upon activation, normal T cell expressed and secreted) levels than those with moderate disease, especially when allowance was made for disease duration (all P < 0.05). Reduced cytokine/chemokine levels in severe disease were also seen in children with other viral infections. Gene expression analysis of nasopharyngeal aspiration samples (n = 43) confirmed reduced type-I IFN gene expression in severe bronchiolitis accompanied by enhanced expression of MUC5AC and IL17A., Conclusions: Infants with severe RSV bronchiolitis have lower nasal viral load, CXCL10 (C-X-C motif chemokine ligand 10)/IP-10, and type-I IFN levels than moderately ill children, but enhanced MUC5AC (mucin-5AC) and IL17A gene expression in nasal cells.

Inhaled administration is underutilised because the drug discovery process is viewed as challenging, risky, and expensive. However, unmet medical need continues to grow, and significant opportunities exist to discover novel inhaled medicines delivering the required lung concentrations while minimising systemic exposure. This profile could be achieved by a combination of properties, including lung retention and low oral bioavailability. Property-based rules exist for orally administered compounds, but there has been limited progress defining in silico predictors to guide the discovery of novel inhaled drugs. Recently, the use of informative cell- and tissue-based screens has greatly facilitated the identification of compounds with optimal characteristics for inhaled delivery. Here, we address opportunities for novel inhaled drugs, and the key challenges and uncertainties hampering progress., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background and Purpose: Effective anti-respiratory syncytial virus (RSV) agents are still not available for clinical use. Current major targets are virus surface proteins, such as a fusion protein involved in viral entry, but agents effective after RSV infection is established are required. Here we have investigated the effects of late therapeutic intervention with a novel inhaled RSV polymerase inhibitor, PC786, on RSV infection in human airway epithelium., Experimental Approach: Air liquid interface-cultured bronchial or small airway epithelium was infected with RSVA2. PC786 was applied apically or basolaterally once daily following peak virus load on Day 3 post inoculation. Apical wash was collected daily for determination of viral burden by PCR and plaque assay (primary endpoints) and biomarker analyses. The effects were compared with those of ALS-8112, an anti-RSV nucleoside analogue, and GS-5806, a fusion-protein inhibitor, which were treated basolaterally., Key Results: Late intervention with GS-5806 did not show significant anti-viral effects, but PC786 produced potent, concentration-dependent inhibition of viral replication with viral load falling below detectable limits 3 days after treatment commenced in airway epithelium. These effects were superior to those of ALS-8112. PC786 showed inhibitory activities against RSV-induced increases of CCL5, IL-6, double-strand DNA and mucin. The effects of PC786 were also confirmed in small airway epithelium., Conclusion and Implications: Late therapeutic intervention with the RSV polymerase inhibitor, PC786, reduced the viral burden quickly in human airway epithelium. Thus, PC786 demonstrates the potential to be an effective therapeutic agent to treat active RSV infection., (© 2018 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

The antifungal effects of the novel triazole PC1244, designed for topical or inhaled administration, against Aspergillus fumigatus were tested in a range of in vitro and in vivo studies. PC1244 demonstrated potent antifungal activities against clinical A. fumigatus isolates ( n = 96) with a MIC range of 0.016 to 0.25 μg/ml, whereas the MIC range for voriconazole was 0.25 to 0.5 μg/ml. PC1244 was a strong tight-binding inhibitor of recombinant A. fumigatus CYP51A and CYP51B (sterol 14α-demethylase) enzymes and strongly inhibited ergosterol synthesis in A. fumigatus with a 50% inhibitory concentration of 8 nM. PC1244 was effective against a broad spectrum of pathogenic fungi (MIC range, <0.0078 to 2 μg/ml), especially Aspergillus terreus , Trichophyton rubrum , Candida albicans , Candida glabrata , Candida krusei , Cryptococcus gattii , Cryptococcus neoformans , and Rhizopus oryzae PC1244 also proved to be quickly absorbed into both A. fumigatus hyphae and bronchial epithelial cells, producing persistent antifungal effects. In addition, PC1244 showed fungicidal activity (minimum fungicidal concentration, 2 μg/ml) which indicated that it was 8-fold more potent than voriconazole. In vivo , once-daily intranasal administration of PC1244 (3.2 to 80 μg/ml) to temporarily neutropenic, immunocompromised mice 24 h after inoculation with itraconazole-susceptible A. fumigatus substantially reduced the fungal load in the lung, the galactomannan concentration in serum, and circulating inflammatory cytokine levels. Furthermore, 7 days of extended prophylaxis with PC1244 showed in vivo effects superior to those of 1 day of prophylactic treatment, suggesting accumulation of the effects of PC1244. Thus, PC1244 has the potential to be a novel therapy for the treatment of A. fumigatus infection in the lungs of humans., (Copyright © 2018 Colley et al.)

Although anti-fungal triazoles are dosed orally or systemically for Aspergillus fumigatus infection, systemic adverse events and limited exposure of the lung cavity would make a topical treatment for the lung an attractive option. In this study, we examined the effects of intranasally dosed posaconazole on survival rates and biomarkers in A. fumigatus (itraconazole susceptible: ATCC13073 [Af]; or resistant: NCPF7100 [AfR]) infected, temporarily neutropenic A/J mice. Once daily treatment produced a dose-dependent improvement of survival of Af-infected mice (ED 50 : 0.019 mg/mouse [approx. 0.755 mg/kg, in]), similar to its potency (ED 50 : 0.775 mg/kg, po) after once daily oral dosing. For AfR infection, either intranasal or oral posaconazole was largely ineffective on survival, although the highest dose of intranasal treatment (0.35 mg/mouse) achieved 75% survival rate. Early intervention (treated on days 0, 1, 2 and 3 postinfection) and late intervention (treated on days 1, 2 and 3) with intranasal posaconazole (0.014-0.35 mg/mouse) demonstrated potent inhibition of lung fungal load and galactomannan levels in both bronchoalveolar lavage fluid (BALF) and serum as well as inflammatory cells, IFN-γ, IL-17 and malondialdehyde (MDA) in BALF. Thus, posaconazole when dosed intranasally once daily showed an improvement of survival equivalent to or better than oral treatment, and produced potent inhibition of fungal load and biomarkers., (© 2017 The Authors. Mycoses Published by Blackwell Verlag GmbH.)

PC945 is a novel triazole optimized for lung delivery, and the objective of this study is to determine the effects of intranasally dosed PC945 on Aspergillus fumigatus infection and associated biomarkers in immunocompromised mice. PC945, posaconazole, or voriconazole was administered intranasally once daily on days 0 to 3 (early intervention) or days 1 to 3 (late intervention) postinfection in temporarily neutropenic A/J mice infected intranasally with A. fumigatus , and bronchoalveolar lavage fluid (BALF) and serum were collected on day 3. The effects of extended prophylaxis treatment (daily from days -7 to +3 or days -7 to 0) were also compared with those of the shorter treatment regimens (days -1 to +3 or days -1 and 0). Early and late interventions with PC945 (2.8 to 350 μg/mouse; approximately 0.11 to ∼14 mg/kg of body weight) were found to inhibit lung fungal loads and to decrease the concentrations of galactomannan (GM) in both BALF and serum as well as several biomarkers in BALF (interferon gamma [IFN-γ], interleukin-17 [IL-17], and malondialdehyde) and serum (tumor necrosis factor alpha [TNF-α] and IL-6) in a dose-dependent manner and were >3- and >47-fold more potent than intranasally dosed posaconazole and voriconazole, respectively. Furthermore, extended prophylaxis with low-dose PC945 (0.56 μg/mouse; 0.022 mg/kg) was found to inhibit fungal loads and to decrease the concentrations biomarkers more potently than did the shorter treatment regimens. Thus, PC945 dosed intranasally once daily showed potent antifungal effects, and the effects of PC945 accumulated upon repeat dosing and were persistent. Therefore, PC945 has the potential to be a novel inhaled therapy for the treatment of A. fumigatus infection in humans., (Copyright © 2017 Kimura et al.)

Although respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infection in infants and young children, attempts to develop an effective therapy have so far proved unsuccessful. Here we report the preclinical profiles of PC786, a potent nonnucleoside RSV L protein polymerase inhibitor, designed for inhalation treatment of RSV infection. PC786 demonstrated a potent and selective antiviral activity against laboratory-adapted or clinical isolates of RSV-A (50% inhibitory concentration [IC 50 ], <0.09 to 0.71 nM) and RSV-B (IC 50 , 1.3 to 50.6 nM), which were determined by inhibition of cytopathic effects in HEp-2 cells without causing detectable cytotoxicity. The underlying inhibition of virus replication was confirmed by PCR analysis. The effects of PC786 were largely unaffected by the multiplicity of infection (MOI) and were retained in the face of established RSV replication in a time-of-addition study. Persistent anti-RSV effects of PC786 were also demonstrated in human bronchial epithelial cells. In vivo intranasal once daily dosing with PC786 was able to reduce the virus load to undetectable levels in lung homogenates from RSV-infected mice and cotton rats. Treatment with escalating concentrations identified a dominant mutation in the L protein (Y1631H) in vitro In addition, PC786 potently inhibited RSV RNA-dependent RNA polymerase (RdRp) activity in a cell-free enzyme assay and minigenome assay in HEp-2 cells (IC 50 , 2.1 and 0.5 nM, respectively). Thus, PC786 was shown to be a potent anti-RSV agent via inhibition of RdRp activity, making topical treatment with this compound a novel potential therapy for the treatment of human RSV infections., (Copyright © 2017 Coates et al.)

The development of novel non-nucleoside inhibitors of the RSV polymerase complex is of significant clinical interest. Compounds derived from the benzothienoazepine core, such as AZ-27, are potent inhibitors of RSV viruses of the A-subgroup, but are only moderately active against the B serotype and as yet have not demonstrated activity in vivo. Herein we report the discovery of several novel families of C-2 arylated benzothienoazepine derivatives that are highly potent RSV polymerase inhibitors and reveal an exemplary structure, compound 4a, which shows low nanomolar activity against both RSV A and B viral subtypes. Furthermore, this compound is effective at suppressing viral replication, when administered intranasally, in a rodent model of RSV infection. These results suggest that compounds belonging to this chemotypes have the potential to provide superior anti-RSV agents than those currently available for clinical use., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The profile of PC945, a novel triazole antifungal designed for administration via inhalation, was assessed in a range of in vitro and in vivo studies. PC945 was characterized as a potent, tightly binding inhibitor of Aspergillus fumigatus sterol 14α-demethylase (CYP51A and CYP51B) activity (50% inhibitory concentrations [IC 50 s], 0.23 μM and 0.22 μM, respectively) with characteristic type II azole binding spectra. Against 96 clinically isolated A. fumigatus strains, the MIC values of PC945 ranged from 0.032 to >8 μg/ml, while those of voriconazole ranged from 0.064 to 4 μg/ml. Spectrophotometric analysis of the effects of PC945 against itraconazole-susceptible and -resistant A. fumigatus growth yielded IC 50 (determined based on optical density [OD]) values of 0.0012 to 0.034 μg/ml, whereas voriconazole (0.019 to >1 μg/ml) was less effective than PC945. PC945 was effective against a broad spectrum of pathogenic fungi (with MICs ranging from 0.0078 to 2 μg/ml), including Aspergillus terreus , Trichophyton rubrum , Candida albicans , Candida glabrata , Candida krusei , Cryptococcus gattii , Cryptococcus neoformans , and Rhizopus oryzae (1 or 2 isolates each). In addition, when A. fumigatus hyphae or human bronchial cells were treated with PC945 and then washed, PC945 was found to be absorbed quickly into both target and nontarget cells and to produce persistent antifungal effects. Among temporarily neutropenic immunocompromised mice infected with A. fumigatus intranasally, 50% of the animals survived until day 7 when treated intranasally with PC945 at 0.56 μg/mouse, while posaconazole showed similar effects (44%) at 14 μg/mouse. This profile affirms that topical treatment with PC945 should provide potent antifungal activity in the lung., (Copyright © 2017 Colley et al.)

Background: Existing respiratory mucosal sampling methods are flawed, particularly in a pediatric bronchiolitis setting., Methods: Twenty-four infants with bronchiolitis were recruited: 12 were respiratory syncytial virus (RSV)-positive, 12 were RSV-negative. Infants were sampled by nasosorption and nasopharyngeal aspiration (NPA)., Results: Nasosorption was well tolerated and identified all RSV+ samples. RSV load measured by nasosorption (but not NPA) correlated with length of hospital stay (P = .04) and requirement for mechanical ventilation (P = .03). Nasosorption (but not NPA) levels of interferon γ, interleukin 1β, CCL5/RANTES, and interleukin 10 (IL-10) were elevated in RSV+ bronchiolitis (all P < .05), furthermore CCL5 and IL-10 correlated with RSV load (P < .05)., Conclusions: Nasosorption allowed measurement of RSV load and the mucosal inflammatory response in infants., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.)

The discovery of a novel series of therapeutic agents that has been designed and optimized for treating chronic obstructive pulmonary disease is reported. The pharmacological strategy was based on the identification of compounds that inhibit a defined subset of kinase enzymes modulating inflammatory processes that would be effective against steroid refractory disease and exhibit a sustained duration of action after inhaled delivery.

We present a method for investigating the dynamic pharmacological modulation of pain-related brain activity, measured by BOLD-contrast fMRI. Noxious thermal stimulation was combined with a single infusion and washout of remifentanil, a short-acting opioid analgesic agent. The temporal profile of the effect site concentration of remifentanil, estimated from a pharmacokinetic model, was incorporated into a linear model of the fMRI data. The methodology was tested in nine healthy male subjects. During each imaging session the subjects received noxious thermal stimulation to the back of the left hand, prior to infusion, during infusion to a remifentanil effect site concentration of 1.0 ng/ml, and during washout of the remifentanil. Infusions were repeated with saline. Remifentanil-induced analgesia was confirmed from subjective pain intensity scores. Pain-related brain activity was identified in a matrix of regions using a linear model of the transient BOLD responses to noxious stimulation. Of those regions, there was a significant fractional reduction in the amplitude of the pain-related BOLD response in the insular cortex contralateral to the stimulus, the ipsilateral insular cortex, and the anterior cingulate cortex. Statistical parametric mapping of the component of pain-related BOLD responses that was linearly scaled by remifentanil concentration confirmed the contralateral insular cortex as the pain-processing region most significantly modulated by remifentanil compared to saline. The mapping of specific modulation of pain-related brain activity is directly relevant for understanding pharmacological analgesia. The method of examining time-dependent pharmacological modulation of specific brain activity may be generalized to other drugs that modulate brain activity other than that associated with pain.