Quel est le délai de fabrication d’un vaccin ? – Dan Kwartler

0:06 When a new pathogen emerges,

0:08 our bodies and healthcare systems are left vulnerable.

0:12 In times like these, there’s an urgent need for a vaccine

0:16 to create widespread immunity with minimal loss of life.

0:19 So how quickly can we develop vaccines when we need them most?

0:23 Vaccine development can generally be split into three phases.

0:27 In exploratory research, scientists experiment with different approaches

0:32 to find safe and replicable vaccine designs.

0:35 Once these are vetted in the lab, they enter clinical testing,

0:39 where vaccines are evaluated for safety, efficacy,

0:42 and side effects across a variety of populations.

0:47 Finally, there’s manufacturing,

0:49 where vaccines are produced and distributed for public use.

0:53 Under regular circumstances, this process takes an average of 15 to 20 years.

0:59 But during a pandemic, researchers employ numerous strategies to move

1:03 through each stage as quickly as possible.

1:06 Exploratory research is perhaps the most flexible.

1:09 The goal of this stage is to find a safe

1:12 way to introduce our immune system to the virus or bacteria.

1:16 This gives our body the information it needs

1:20 to create antibodies capable of fighting a real infection.

1:24 There are many ways to safely trigger this immune response,

1:27 but generally, the most effective designs are also the slowest to produce.

1:33 Traditional attenuated vaccines create long lasting resilience.

1:37 But they rely on weakened viral strains that must

1:40 be cultivated in non-human tissue over long periods of time.

1:44 Inactivated vaccines take a much faster approach,

1:47 directly applying heat, acid, or radiation to weaken the pathogen.

1:53 Sub-unit vaccines, that inject harmless fragments of viral proteins,

1:58 can also be created quickly.

2:00 But these faster techniques produce less robust resilience.

2:05 These are just three of many vaccine designs, each with their own pros and cons.

2:10 No single approach is guaranteed to work,

2:13 and all of them require time-consuming research.

2:16 So the best way to speed things up is

2:19 for many labs to work on different models simultaneously.

2:23 This race-to-the-finish strategy produced the first

2:27 testable Zika vaccine in 7 months,

2:29 and the first testable COVID-19 vaccine in just 42 days.

2:35 Being testable doesn’t mean these vaccines will be successful.

2:39 But models that are deemed safe and easily replicable can

2:42 move into clinical testing while other labs continue exploring alternatives.

2:47 Whether a testable vaccine is produced in four months or four years,

2:51 the next stage is often the longest and most unpredictable stage of development.

2:56 Clinical testing consists of three phases, each containing multiple trials.

3:02 Phase I trials focus on the intensity of the triggered immune response,

3:07 and try to establish that the vaccine is safe and effective.

3:10 Phase II trials focus on determining the right

3:13 dosage and delivery schedule across a wider population.

3:17 And Phase III trials determine safety

3:19 across the vaccine’s primary use population,

3:23 while also identifying rare side effects and negative reactions.

3:27 Given the number of variables and the focus on long-term safety,

3:31 it’s incredibly difficult to speed up clinical testing.

3:35 In extreme circumstances,

3:37 researchers run multiple trials within one phase at the same time.

3:41 But they still need to meet strict safety criteria before moving on.

3:46 Occasionally, labs can expedite this process

3:48 by leveraging previously approved treatments.

3:52 In 2009, researchers adapted the seasonal flu vaccine to treat

3:58 H1N1— producing a widely available vaccine in just six months.

4:03 However, this technique only works when dealing

4:06 with familiar pathogens that have well-established vaccine designs.

4:11 After a successful Phase III trial,

4:14 a national regulatory authority reviews the results

4:18 and approves safe vaccines for manufacturing.

4:21 Every vaccine has a unique blend of biological

4:24 and chemical components that require a specialized pipeline to produce.

4:29 To start production as soon as the vaccine is approved,

4:32 manufacturing plans must be designed in parallel to research and testing.

4:37 This requires constant coordination between labs and manufacturers,

4:42 as well as the resources to adapt to sudden changes

4:45 in vaccine design— even if that means scrapping months of work.

4:50 Over time, advances in exploratory research

4:53 and manufacturing should make this process faster.

4:56 Preliminary studies suggest that future researchers may be able to swap

5:01 genetic material from different viruses into the same vaccine design.

5:06 These DNA and mRNA based vaccines could

5:10 dramatically expedite all three stages of vaccine production.

5:13 But until such breakthroughs arrive,

5:15 our best strategy is for labs around the world

5:19 to cooperate and work in parallel on different approaches.

5:22 By sharing knowledge and resources,

5:24 scientists can divide and conquer any pathogen.