Identification and characterization of novel compounds with broad spectrum antiviral activity against influenza A and B viruses.
- 作者列表："Park JG","Ávila-Pérez G","Nogales A","Blanco-Lobo P","de la Torre JC","Martínez-Sobrido L
:Influenza A (IAV) and B (IBV) viruses are highly contagious pathogens that cause fatal respiratory disease every year with a high economic impact. In addition, IAV can cause pandemic infections of great consequences when new viruses are introduced into humans. In this study we evaluated ten previously described compounds with antiviral activity against mammarenaviruses for their ability to inhibit IAV infection using our recently described bi-reporter influenza A/Puerto Rico/8/34 H1N1 (BIRFLU). Among the ten tested compounds, eight [antimycin A (AmA), brequinar (BRQ), 6-azauridine, azaribine, pyrazofurin (PF), AVN-944, mycophenolate mofetil (MMF) and mycophenolic acid (MPA)], but not obatoclax and Osu-03012, showed potent anti-influenza virus activity in post-treatment conditions (EC50 = 3.80 nM to 1.73 μM, SI-MTT > 28.90 to 13,157.89). AmA, 6-azauridine, azaribine and PF also showed potent inhibitory effect in pre-treatment (EC50 = 0.14 μM to 0.55 μM, SI-MTT = 70.12 to > 357.14) or co-treatment (EC50 = 34.69 nM to 7.52 μM, SI-MTT = 5.24 to > 1,441.33) settings. All of the compounds tested inhibited viral genome replication and gene transcription and none of them affected host cellular RNA polymerase II activities. The antiviral activity of the eight identified compounds against BIRFLU was further confirmed with seasonal IAVs (A/California/04/2009 H1N1 and A/Wyoming/3/2003 H3N2) and an IBV (B/Brisbane/60/2008, Victoria lineage), demonstrating their broad-spectrum prophylactic and therapeutic activity against currently circulating influenza viruses in humans. Altogether, our results identified a new set of antiviral compounds for the potential treatment of influenza viral infections.IMPORTANCE Influenza viruses are highly contagious pathogens and cause a major threat to human health. Vaccination remains the most effective tool to protect humans against influenza infection. However, vaccination does not always guarantee complete protection against drifted or, more noticeable, shifted influenza viruses. Although Food and Drug Administration (FDA) drugs are approved for the treatment of influenza infections, resistant influenza viruses to current FDA antivirals have been reported and continue to emerge. Therefore, there is an urgent need to find novel antivirals for the treatment of influenza viral infections in humans, a search that could be expedited by repurposing currently approved drugs. In this study, we assessed the influenza antiviral activity of ten compounds previously shown to inhibit mammarenavirus infection. Among them, eight drugs showed antiviral activities, providing a new battery of drugs that could be used for the treatment of influenza infections.
甲型流感病毒 (IAV) 和乙型流感病毒 (IBV) 是具有高度传染性的病原体，每年都会引起致命的呼吸系统疾病，并对经济产生巨大影响。此外，当新病毒引入人类时，IAV 会引起后果很大的大流行感染。在这项研究中，我们使用我们最近描述的双报告流感 A/波多黎各/8/34 H1N1 (BIRFLU)，评价了 10 种以前描述的具有抗 mammarenavirus 抗病毒活性的化合物抑制 IAV 感染的能力。在十个受试化合物中，有 8 个 [抗霉素 A (AmA) 、 brequinar (BRQ) 、 6-氮杂吡啶、氮杂嘧啶、吡唑呋喃 (PF) 、 AVN-944 、霉酚酸酯 (MMF) 和麦考酚酸 (MPA)]，但不是 obatoclax 和 Osu-03012，在后处理条件下表现出强效的抗流感病毒活性(EC50 = 3.80 nM 至 1.73 μ m，SI-MTT> 28.90 至 13,157.89)。AmA 、 6-氮杂环苯胺、氮杂嘧啶和 PF 在预处理中也表现出强效抑制作用 (EC50 = 0.14 μ m 至 0.55 μ m，SI-MTT = 70.12 至> 357.14) 或共同处理 (EC50 = 34.69 nM 至 7.52 μ m，SI-MTT = 5.24 至> 1,441.33) 设置。所有受试化合物均抑制病毒基因组复制和基因转录，均不影响宿主细胞 RNA 聚合酶 ⅱ 活性。8 种已鉴定的化合物对禽流感的抗病毒活性进一步得到季节性 IAVs (A/California/04/2009 H1N1 和 A/Wyoming/3/2003 H3N2) 的证实和 IBV (B/Brisbane/60/2008，Victoria 谱系)，证明了它们对目前人类流行的流感病毒的广谱预防和治疗活性。总之，我们的研究结果确定了一组新的抗病毒化合物，用于治疗流感病毒感染。重要性流感病毒是高度传染性病原体，对人类健康造成重大威胁。疫苗接种仍然是保护人类免受流感感染的最有效工具。然而，疫苗接种并不总是保证对漂移或更明显的移位流感病毒的完全保护。虽然食品和药物管理局 (FDA) 的药物被批准用于治疗流感感染，流感病毒对目前的 FDA 抗病毒药物的耐药性已经报道并继续出现。因此，迫切需要找到治疗人类流感病毒感染的新型抗病毒药物，通过重新利用目前批准的药物来加快搜索。在这项研究中，我们评估了 10 个以前显示抑制乳腺病毒感染的化合物的流感抗病毒活性。其中，八种药物显示出抗病毒活性，提供了一组新的药物，可用于治疗流感感染。
METHODS:BACKGROUND:From 2015/16 through 2017/18, injectable, trivalent inactivated influenza vaccines (IIV3) and a nasal spray, tetravalent live-attenuated influenza vaccine (LAIV4) were used in parallel in Finland. To understand how well vaccination with each vaccine type protected children against influenza under real-life conditions, vaccine effectiveness in two-year-olds was estimated for all three seasons. METHODS:Each season, a nationwide register-based cohort study was conducted. The study population comprised 60,088 children in 2015/16, 60,860 children in 2016/17 and 60,345 children in 2017/18. Laboratory-confirmed influenza was the study outcome. Seasonal influenza vaccination with either LAIV4 or IIV3 was the time-dependent exposure of interest. Vaccine effectiveness was defined as 1 minus the hazard ratio comparing vaccinated with unvaccinated children. RESULTS:From 2015/16 through 2017/18, the effectiveness of LAIV4 against influenza of any virus type was estimated at 54.2% (95% confidence interval, 32.2%-69.0%), 20.3% (-12.7% to 43.6%) and 30.5% (10.9%-45.9%); the corresponding effectiveness of IIV3 was 77.2% (48.9%-89.8%), 24.5% (-29.8% to 56.1%) and -20.1% (-61.5% to 10.7%). Neither of the influenza vaccines clearly excelled in protecting children. The LAIV4 effectiveness against type B was greater than against type A and greater than the IIV3 effectiveness against type B. CONCLUSIONS:To understand how influenza vaccines could be improved, vaccine effectiveness must be analyzed by vaccine and virus type. Effectiveness estimates expressing also overall protection levels are needed to guide individual and programmatic decision-making processes. Supported by this analysis, the vaccination program in Finland now recommends LAIV4 and injectable, tetravalent inactivated influenza vaccines replacing IIV3.
METHODS::Intranasally administered influenza vaccines could be more effective than injected vaccines, since intranasal vaccination can induce virus-specific IgA antibodies in the upper respiratory tract, which is the initial site of infection. In the current study, immune responses elicited by an intranasal inactivated H5 influenza vaccine were evaluated in healthy H5 influenza virus-naive individuals. Three doses of intranasal inactivated whole-virion H5 influenza vaccine induced strong neutralizing nasal IgA and serum IgG antibodies. In addition, a mucoadhesive excipient, carboxy-vinyl polymer (CVP), had a notable impact on the induction of nasal IgA antibody responses but not serum IgG antibody responses. The nasal hemagglutinin (HA)-specific IgA antibody responses clearly correlated with mucosal neutralizing antibody responses, indicating that measurement of nasal HA-specific IgA titers could be used as a surrogate for the mucosal antibody response. Furthermore, increased numbers of plasma cells and vaccine antigen-specific helper T (Th) cells in the peripheral blood were observed after vaccination, suggesting that peripheral blood biomarkers may also be used to evaluate the intranasal vaccine-induced immune response. However, peripheral blood immune cell responses correlated with neutralizing antibody titers in serum samples but not in nasal wash samples. Thus, analysis of the peripheral blood immune response could be a surrogate for the systemic immune response to intranasal vaccination but not for the mucosal immune response. The current study suggests the clinical potential of intranasal inactivated vaccines against H5 influenza viruses and highlights the need to develop novel means to evaluate intranasal vaccine-induced mucosal immune responses. This article is protected by copyright. All rights reserved.
METHODS:BACKGROUND:Influenza is an important public health problem and existing vaccines are not completely protective. New vaccines that protect by alternative mechanisms are needed to improve efficacy of influenza vaccines. In 2015, we did a phase 1 trial of an oral influenza vaccine, VXA-A1.1. A favourable safety profile and robust immunogenicity results in that trial supported progression of the vaccine to the current phase 2 trial. The aim of this study was to evaluate efficacy of the vaccine in a human influenza challenge model. METHODS:We did a single-site, placebo-controlled and active-controlled, phase 2 study at WCCT Global, Costa Mesa, CA, USA. Eligible individuals had an initial A/California/H1N1 haemagglutination inhibition titre of less than 20 and were aged 18-49 years and in good health. Individuals were randomly assigned (2:2:1) to receive a single immunisation of either 1011 infectious units of VXA-A1.1 (a monovalent tablet vaccine) orally, a full human dose of quadrivalent inactivated influenza vaccine (IIV) via intramuscular injection, or matched placebo. Randomisation was done by computer-generated assignments with block size of five. An unmasked pharmacist provided the appropriate vaccines and placebos to the administrating nurse. Individuals receiving the treatments, investigators, and staff were all masked to group assignments. 90 days after immunisation, individuals without clinically significant symptoms or signs of influenza, an oral temperature of higher than 37·9°C, a positive result for respiratory viral shedding on a Biofire test, and any investigator-assessed contraindications were challenged intranasally with 0·5 mL wild-type A/CA/like(H1N1)pdm09 influenza virus. The primary outcomes were safety, which was assessed in all immunised participants through 365 days, and influenza-positive illness after viral challenge, which was assessed in individuals that received the viral challenge and the required number of assessments post viral challenge. This trial is registered with ClinicalTrials.gov, number NCT02918006. RESULTS:Between Aug 31, 2016, and Jan 23, 2017, 374 individuals were assessed for eligibility, of whom 179 were randomly assigned to receive either VXA-A1.1 (n=71 [one individual did not provide a diary card, thus the solicited events were assessed in 70 individuals]), IIV (n=72), or placebo (n=36). Between Dec 2, 2016, and April 26, 2017, 143 eligible individuals (58 in the VXA-A1.1 group, 54 in the IIV group, and 31 in the placebo group) were challenged with influenza virus. VXA-A1.1 was well tolerated with no serious or medically significant adverse events. The most prevalent solicited adverse events for each of the treatment groups after immunisation were headache in the VXA-A1.1 (in five [7%] of 70 participants) and placebo (in seven [19%] of 36 participants) groups and tenderness at injection site in the IIV group (in 19 [26%] of 72 participants) Influenza-positive illness after challenge was detected in 17 (29%) of 58 individuals in the VXA-A1.1 group, 19 (35%) of 54 in the IIV group, and 15 (48%) of 31 in the placebo group. INTERPRETATION:Orally administered VXA-A1.1 was well tolerated and generated protective immunity against virus shedding, similar to a licensed intramuscular IIV. These results represent a major step forward in developing a safe and effective oral influenza vaccine. FUNDING:Department of Health and Human Services, Office of the Assistant Secretary for Preparedness and Response, and Biomedical Advanced Research and Development Authority.