How fast can a vaccine be made? - Dan Kwartler

譯者: Lilian Chiu 審譯者: Helen Chang

When a new pathogen emerges,

一旦出現新的病原體，

our bodies and healthcare systems are left vulnerable.

人體和健康照護系統就變得脆弱。

In times like these, there’s an urgent need for a vaccine

這時候就迫切需要疫苗，

to create widespread immunity with minimal loss of life.

將免疫力大量散播出去， 讓人命損失減至最低。

So how quickly can we develop vaccines when we need them most?

所以，在最需要的時候， 我們能以多快的速度開發出疫苗？

Vaccine development can generally be split into three phases.

一般而言，疫苗開發 可以分為三階段。

In exploratory research, scientists experiment with different approaches

在探索性研究階段， 科學家會實驗不同的方法，

to find safe and replicable vaccine designs.

以找出安全且可複製的疫苗設計。

Once these are vetted in the lab, they enter clinical testing,

一旦在實驗室中完成審查之後， 就會進入臨床測試階段，

where vaccines are evaluated for safety, efficacy, and side effects

要測試的包括疫苗 對各種不同族群的

安全性、效力，以及副作用。

across a variety of populations.

Finally, there’s manufacturing,

最後是生產製造階段，

where vaccines are produced and distributed for public use.

此時要生產疫苗， 散佈出去給大眾使用。

Under regular circumstances, this process takes an average of 15 to 20 years.

在一般的情況下，

這個流程平均要花 十五到二十年的時間。

But during a pandemic, researchers employ numerous strategies

但在疫情進入全球大流行時， 研究者會採用數種策略

to move through each stage as quickly as possible.

盡快完成每個階段。

Exploratory research is perhaps the most flexible.

探索性研究可能是最有彈性的。

The goal of this stage is to find a safe way

這個階段的目標是要 找出安全的方式，

to introduce our immune system to the virus or bacteria.

讓我們的免疫系統認識 這種病毒或細菌。

This gives our body the information it needs to create antibodies

這麼一來，我們的身體 就能得到必要的資訊，

可以創造出抗體， 來對抗實際的感染。

capable of fighting a real infection.

There are many ways to safely trigger this immune response,

有許多方式能安全地 觸發這種免疫反應，

but generally, the most effective designs are also the slowest to produce.

但一般而言，最有效的設計 生產速度也最慢。

Traditional attenuated vaccines create long lasting resilience.

傳統的活性減毒疫苗 會創造出長效的恢復力。

But they rely on weakened viral strains

但這類疫苗要仰賴 長時間在非人類組織中

that must be cultivated in non-human tissue over long periods of time.

培養出來的減毒病毒株。

Inactivated vaccines take a much faster approach,

不活化疫苗用的方法就快很多，

directly applying heat, acid, or radiation to weaken the pathogen.

直接使用熱、酸， 或輻射將病原體減毒。

Sub-unit vaccines, that inject harmless fragments of viral proteins,

次單位疫苗注射的是 病毒蛋白質中無害的部分，

can also be created quickly.

開發這種疫苗也很快。

But these faster techniques produce less robust resilience.

但用這些較快技術 所產生的抵抗力較差。

These are just three of many vaccine designs,

以上只是許多疫苗設計中的三種，

each with their own pros and cons.

每種都各有其優缺點。

No single approach is guaranteed to work,

無法保證哪一種方法絕對行得通，

and all of them require time-consuming research.

且這些方法全都需要耗時的研究。

So the best way to speed things up is for many labs

加速開發疫苗最好的辦法就是

由許多實驗室同時投入不同的模型。

to work on different models simultaneously.

This race-to-the-finish strategy

這種賽跑看誰先到終點的策略

produced the first testable Zika vaccine in 7 months,

曾經在七個月內製造出 最早可測試的茲卡疫苗，

and the first testable COVID-19 vaccine in just 42 days.

並在短短四十二天內製造出最早 可測試的新型冠狀病毒疫苗。

Being testable doesn’t mean these vaccines will be successful.

那些疫苗只是可測試， 並不表示已經成功。

But models that are deemed safe and easily replicable

但被視為安全且容易複製的模型

can move into clinical testing while other labs continue exploring alternatives.

就能進入臨床測試，同時其他 實驗室則會繼續探索替代方案。

Whether a testable vaccine is produced in four months or four years,

不論是花四個月或四年 生產出來的可測試疫苗，

the next stage is often the longest and most unpredictable stage of development.

下一個階段通常都是開發過程中 最漫長也最無法預測的階段。

Clinical testing consists of three phases, each containing multiple trials.

臨床測試包含三個階段， 每個階段都要做多個試驗。

Phase I trials focus on the intensity of the triggered immune response,

第一階段試驗著重在 觸發的免疫反應有多強，

and try to establish that the vaccine is safe and effective.

嘗試確認疫苗安全有效。

Phase II trials focus on determining the right dosage and delivery schedule

第二階段試驗著重在針對各種族群

決定適當的劑量以及施打時程表。

across a wider population.

And Phase III trials determine safety

第三階段試驗著重在判斷

across the vaccine’s primary use population,

疫苗對於其主要使用族群是否安全，

while also identifying rare side effects and negative reactions.

同時也要找出罕見的 副作用及負面反應。

Given the number of variables and the focus on long-term safety,

因為變數很多，且著重長期安全，

it’s incredibly difficult to speed up clinical testing.

要加速臨床測試是難上加難。

In extreme circumstances, researchers run multiple trials

在極端的情況下，研究者會同時

在一個階段中進行多個試驗，

within one phase at the same time.

But they still need to meet strict safety criteria before moving on.

但仍須達到嚴格的安全標準 才能繼續進行。

Occasionally, labs can expedite this process by leveraging

偶爾，實驗室能夠使用 過去核准的處理方式

previously approved treatments.

來加速這個過程。

In 2009, researchers adapted the seasonal flu vaccine to treat H1N1—

2009 年，

研究者採用了季節性 流感疫苗來治療 H1N1——

producing a widely available vaccine in just six months.

只花了六個月，就產生出 能廣泛使用的疫苗。

However, this technique only works when dealing with familiar pathogens

然而，這種技巧只能用來對付已經

有良好疫苗設計的熟悉病原體，

that have well-established vaccine designs.

After a successful Phase III trial, a national regulatory authority

在第三階段試驗成功之後， 就會由國家的當權規範機關

reviews the results and approves safe vaccines for manufacturing.

來審視結果和批准， 讓安全的疫苗能開始生產製造。

Every vaccine has a unique blend of biological and chemical components

每種疫苗各是不同 生物和化學成份的獨特混合，

that require a specialized pipeline to produce.

需要專門的生產線來生產。

To start production as soon as the vaccine is approved,

若要在疫苗被核准之後 就開始生產製造，

manufacturing plans must be designed in parallel to research and testing.

就必須要在研究和測試的時候 同步進行生產製造計畫。

This requires constant coordination between labs and manufacturers,

實驗室和製造商之間 就得經常協調，

as well as the resources to adapt to sudden changes in vaccine design—

還得有資源配合 可能會突然改變的疫苗設計——

even if that means scrapping months of work.

即使改變可能意味著 幾個月的努力都白費。

Over time, advances in exploratory research and manufacturing

隨著時間，在探索性研究 和生產製造上的進步

should make this process faster.

可能會讓這個流程更快速。

Preliminary studies suggest that future researchers

初步研究指出，未來的研究者

may be able to swap genetic material from different viruses

可能可以將不同病毒的遺傳物質

交換到同樣的疫苗設計中。

into the same vaccine design.

These DNA and mRNA based vaccines could dramatically expedite

這些以疫苗為依據的 DNA 和 mRNA 能夠顯著加快

all three stages of vaccine production.

疫苗生產的三個階段。

But until such breakthroughs arrive,

但，在這種突破出現之前，

our best strategy is for labs around the world to cooperate

我們的最佳策略就是 全世界的實驗室同心協力，

and work in parallel on different approaches.

同步投入不同的方法。

By sharing knowledge and resources,

透過分享知識和資源，

scientists can divide and conquer any pathogen.

科學家定能各個擊破任何病原體。