出国访学需要了解的新冠肺炎疫苗知识(Covid-19 Vaccine)

  导语:2020年新冠疫情席卷全球,我们一起科普新冠疫苗的研发和投入使用情况。
 

  Covid-19 vaccine: “Hopefully next year we'll be living a normal life”

  The Pfizer/BioNTech vaccine - a collaboration between a US pharmaceutical giant and a German biotechnology company - offers up to 95% protection and is the first Covid-19 vaccine to be approved by US regulators.

  It is already being rolled out in the UK, while Canada also began its inoculation programme on Monday, with an initial 30,000 doses going to 14 sites across the country.

  US President-elect Joe Biden, who will be inaugurated as president on 20 January, has set a goal of 100 million Covid vaccinations in his first 100 days in office. That would represent roughly a third of the country’s total population.

  新冠疫苗:“希望明年我们的生活恢复正常”

  辉瑞/ BioNTech疫苗是由一家美国制药巨头与德国生物技术公司共同研发的新冠疫苗,有效性高达95%,现已被美国监管机构批准的首个新冠疫苗。

  辉瑞疫苗现已在英国广泛推广,加拿大也于周一开始了其接种计划,在全国14个点预估接种30,000剂疫苗。

  美国总统当选人拜登(将于1月20日就任总统)公开申明在他上任的头100天,完成 1亿次新冠疫苗接种的目标,大约占美国总人口的三分之一。

  How Scientists Plan to Develop a Coronavirus Vaccine

  As the world continues to feel the impact of COVID-19, the biopharmaceutical industry is working around the clock to identify and develop safe and effective vaccines to prevent infection, while also researching and developing new ways to treat those infected with the virus.

  During this time, biopharmaceutical companies are working continuously with stakeholders across the R&D ecosystem to advance vaccine candidates as quickly and safely as possible.

  Step by step, here’s how scientists are aiming to develop a vaccine for COVID-19:

  随着全球受新冠(COVID-19)病毒的影响,生物制药行业正在全天候工作,尽快研发出能预防新冠的安全有效的疫苗,同时也在研发能治疗新冠患者的新方法。

  在这段时间里,生物制药公司正在与整个研发生态系统的利益相关者持续合作,以尽可能快速、安全地推进疫苗的开发。

  循序渐进,这是科学家们如何研发COVID-19疫苗的过程:
 

  Step 1: Identify And Sequence The Virus

  When evidence of a new virus is detected, scientists work to isolate and identify the specific virus in question. Once isolated, scientists can rapidly sequence the unique genetic code of the new virus, which provides information needed to help design diagnostic tests and potential vaccines and treatments.

  On January 10, 2020, Chinese health officials released the full genetic sequence of the novel coronavirus that can cause COVID-19, just a few weeks after the first case was discovered. The next day, researchers around the world started work on a vaccine.

  By comparison, it took several months after the discovery of SARS in 2002 to sequence the full SARS-CoV-1 genetic code with the tools available at that time. The much faster timeline in the case of COVID-19 illustrates recent improvements technologies that have dramatically shortened the time it takes to decode viruses and create a potential vaccine.

  第一步:识别病毒并对其进行排序

  当检测到新病毒时,科学家将其努力分离并鉴定所讨论的特定病毒。一旦分离出来,科学家们就可以迅速对新病毒的独特遗传密码进行测序,从而提供有助于设计诊断测试以及潜在疫苗和治疗方法的信息。

  2020年1月10日,中国卫生官员在发现第一例新冠病例数周后,发布了可导致COVID-19新型冠状病毒的完整基因序列。第二天,世界各地的研究人员开始研发疫苗。

  相比之下,在2002年发现SARS之后,花了几个月的时间才用当时可用的工具对完整的SARS-CoV-1遗传密码进行测序。对于COVID-19,更快的时间表说明了最近的技术改进,这些技术大大缩短解码病毒和制造可能疫苗所需的时间。
 

  Step 2: Determine The Target

  Vaccines work by imitating an infection to teach the immune system how to recognize, remember and target microbial invaders, like viruses and bacteria, without actually causing an infection. The process to determine how to best deliver a vaccine is complex as different approaches may work better for different pathogens.

  Historically, some vaccines, such as the measles vaccine, have used live but weakened versions of a pathogen, while others have used viral material that has been chemically inactivated or killed, which is the method used by the polio vaccine.

  Newer vaccines, such as the vaccine for hepatitis B, contain only a small part of a pathogen—usually a specific protein that the body can learn to recognize, known as an “antigen.” Given the pressing need for a safe and effective vaccine for the novel coronavirus, along with the volume of information that remains unknown about the disease, a wide range of approaches to vaccine development are being tested by biopharmaceutical researchers throughout the world to greatly improve the odds that one or more of these approaches will be successful.

  第二步:确定目标

  疫苗通过模仿感染来起作用,以指导免疫系统如何识别,记住和靶向微生物入侵者(如病毒和细菌),而不会真正引起感染。由于不同的方法对不同的病原体可能效果更好,因此确定如何最好地提供疫苗的过程是很复杂。

  从历史上看,有些疫苗(例如麻疹疫苗)使用的是活的但变弱的病原体,而另一些疫苗则使用的是化学灭活或杀死的病毒材料,这是脊髓灰质炎疫苗使用的方法。

  诸如乙型肝炎疫苗之类的新型疫苗仅包含一小部分病原体,通常是人体可以学会识别的一种特定蛋白质,称为“抗原”。鉴于迫切需要针对新型冠状病毒的安全有效疫苗,以及有关该疾病的未知信息,世界各地的生物制药研究人员正在测试多种疫苗开发方法,以大大提高成功概率。
 

  Step 3: Conduct Preclinical Trials

  Once researchers identify a vaccine delivery mechanism, cell cultures or animal models are used to test the vaccine’s potential safety and effectiveness. As of June 5, 2020, 129 vaccine candidates have entered preclinical testing.

  Notably, it’s common for vaccine candidates to fail during this part of the process, which is why we need as many shots on goal with as many viable candidates as possible.

  第三部:进行临床前试验

  一旦研究人员确定了疫苗的输送机制,便可以使用细胞培养或动物模型来测试疫苗的潜在安全性和有效性。截至2020年6月5日,已有129种候选疫苗进入临床前测试阶段。

  值得一提的是,候选疫苗在这个测试过程中被淘汰是很常见的,这就是为什么我们需要尽可能多的方案和尽可能多的可行候选的原因。
 

  Step 4: Conduct Clinical Trials

  If a potential vaccine is successful in preclinical studies, scientists begin studying it in humans, which requires multiple types of clinical trials. Initial trials involve just a few dozen participants to provide evidence that a new vaccine is safe and to help researchers optimize dosing amounts. Demonstrating efficacy for vaccines presents unique challenges. Unlike most pivotal clinical trials, subjects in pivotal clinical trials for vaccines are otherwise healthy at the start of the clinical trial. Accordingly, demonstrating efficacy may require longer and larger clinical trials for vaccines than for other products.

  Additional trials examine the vaccine in hundreds to even a few thousand people to better understand how the immune system responds to a vaccine, whether it is effective and durable at producing immunity, and to further understand the vaccine’s safety profile. Depending on the vaccine and disease under study, thousands or even tens of thousands of participants may participate to increase understanding of a vaccine’s safety profile. As of June 5, 2020, ten coronavirus vaccine candidates have entered initial clinical trials.

  第四步:进行临床试验

  如果一种潜在的疫苗在临床前测试中获得成功,科学家将开始在人体中对其进行研究,这需要多种类型的临床试验。最初的试验仅涉及几十名参与者,以提供新疫苗安全的数据,并帮助研究人员优化剂量。证明疫苗的功效是比较挑战的。与大多数关键性临床试验不同,疫苗的关键性临床试验中的受试者在临床试验开始时是健康的。因此,与其他产品相比,证明效力可能需要更长且更大的疫苗临床试验。

  疫苗的其他试验在数百至数千人中进行检查,以更好地了解免疫系统对疫苗的反应,在产生免疫力方面是否有效和持久,以及进一步了解疫苗的安全性。根据所研究的疫苗和疾病的不同,成千上万的参与者可能会参加,以加深对疫苗安全性的了解。截至2020年6月5日,已有十名冠状病毒疫苗候选者进入了初始临床试验。

  Step 5: Obtain Regulatory Approval

  By this point, the majority of vaccine candidates will have failed, underscoring the substantial risks and complexities involved. However, if a vaccine successfully makes it through clinical trial phases, researchers can apply for approval from the U.S. Food and Drug Administration (FDA). Applications for approval must meet FDA’s robust standards for safety, purity and potency to obtain approval, and include data generated pre-clinical testing and clinical trials, in addition to significant information on the manufacturing process.

  第五步:获得监管批准

  至此,大多数候选疫苗都将失败,由此可以看出所涉及的巨大风险和复杂性。但是,如果疫苗成功通过临床试验阶段,则研究人员可以向美国食品药品监督管理局(FDA)申请批准。批准申请必须符合FDA关于安全性,纯度和效力的严格标准,才能获得批准,除有关生产过程的重要信息外,还应包括临床前测试和临床试验产生的数据。
 

  Step 6: Manufacturing And Distribution

  While the vaccine is going through clinical studies, biopharmaceutical researchers are also developing the manufacturing methods that will be used if the new vaccine is successful. For some types of vaccines used in large populations, these methods then undergo massive scale up to enable the manufacture of what can be many millions of doses. This is an enormous undertaking, as the transition from laboratory to manufacturing facility is incredibly complex and must ensure consistency in the vaccine composition and safety and efficacy profiles. As developing the manufacturing strategy can be a multi-year process, biopharmaceutical companies are already seeking to expand their manufacturing capacity. Companies are also initiating manufacturing capabilities at risk, well before a COVID-19 vaccine receives regulatory approval, to speed the production process when a vaccine is ready.

  Safely delivering a vaccine to patients around the world is an equally challenging undertaking, especially in less developed regions, as vaccines often require special handling, such as temperature control, during distribution. Biopharmaceutical companies are working closely with local governments and NGO partners to lay the groundwork for potential distribution at global scale.

  第六步:生产和分销

  在疫苗进行临床研究的同时,生物制药研究人员也在开发新疫苗的制造方法。对于在大批人群中使用的某些类型的疫苗,然后对这些方法进行大规模放大,以制造出数以百万计的剂量。这是一项艰巨的任务,因为从实验室到生产车间的过渡非常复杂,必须确保疫苗成分以及安全性和功效概况的一致性。由于制定制造策略可能需要多年的时间,因此生物制药公司已经在寻求扩大制造能力。在COVID-19疫苗获得监管批准之前,公司也正在启动制造能力,以在准备好疫苗时加快生产过程。

  安全地向世界各地的患者提供疫苗是一项同样具有挑战性的工作,尤其是在欠发达地区,因为疫苗在分发过程中通常需要特殊处理,例如温度控制。生物制药公司正在与地方政府和非盈利组织合作伙伴紧密合作,为在全球范围内进行未来分销奠定基础。