Where is my COVID 19 vaccine?

More than 170 research teams racing.

A thread about progress and concerns:

First, the vaccine should pass through testing and trials:
1.Preclinical: tested on animals, to test if it illicits an immune response
2. Phase 1: tested on a small group of humans, to learn about it's safety on humans and the human immune response.

3. Phase 2: tested on a larger group of people to learn more about dosage and safety.
4. Phase 3: Wide testing on thousands of people, to learn about effectiveness and rare side effects.
Finally, approval if all phases are promising.

The strongest immune response is triggered when the vaccine contains a weaker but live version of the virus that triggers an immune response but doesn't make you as sick, however since we don't know much about the virus, this could be risky.

Instead, the current leading vaccines use a different known harmless virus that delivers a preinjected piece of COVID19 genetic material that your body uses to synthesize The Spike protein (in red) only, which also allows to produce an immune response. A safer but weaker response

Currently there are more than 170 teams working on delivering a COVID19 vaccine, however only 11 so far have reached phase 3 trials, with 4 leading the race.

However, closer to approval, trials will start showing undefined illness in tested subjects causing halting of trials. 2 leading groups, the AstraZeneca/Oxford and J&J paused their vaccine trials recently for causing unknown disease in subjects.

In addition, even though lockdowns and distancing have reduced the virus transmission, they also made the development process slower. To see if the virus is effective, you need people to become infected.

So when?
The trials in phase 3 are expected to continue through the end of 2020 with expected approvals in mid 2021. However early approvals for certain populations are expected by the end of 2020 if trials show marked effectiveness of the vaccine.

The chances are that the first vaccine to be approved won't be the most effective. Also, it might not be the one you're going to get. Other trials will continue that will bring us better vaccines, that will not require boosters or delivery challenges.

What delivery challenges?
Since the leading vaccines contain biologic material, they need to be stored in cold temperatures up until delivery. The challenge is delivering a refrigerated vaccine across the globe. 25% of vaccines are estimated to be spoiled upon roll-out.

Will my country get it?
Another challenge is who gets the vaccine first. Debate is still going but major challenge is the rise of vaccine nationalism (VN)

VN is when countries sign a deal with pharmaceutical companies to get the vaccine before it becomes available for other countries. Wealthy countries have already signed deals to secure 3.7b doses, while poorer countries remain at risk of not getting the virus in due time.

WHO and partners are aware of this ethical dilemma and they launched the COVAX initiative. This will prevent vaccine hoarding and ensure that it will be delivered to the high risk populations in all countries that signed the initiative, mainly health workers and the elderly.

Wealthy countries that sign the COVAX initiative will fund the vaccine purchase and partner with 92 poorer nations that won't be able to afford it. 172 countries (70% of the population) had showed interest and Lebanon has already signed up for the initiative.

How many vaccines do we need?
This is where herd immunity becomes relevant. An estimate is that 60-70% of the population will need to be immune to halt the spread of the virus.

As the whole world demands a quick vaccine development, we should know that development of new drugs is a process that takes years. However, with the massive funding and global effort/interest we will be able to see one of history's fastest drug development.

The development process though is the lesser concern when faced with the technical and ethical challenge of delivering the vaccine to the people who most need it in the right time and adequate effectiveness.

End of thread.