The good and not-so-good news about the state of COVID-19 vaccine development: A primer from ILRI

Jimmy Smith, director general of the International Livestock Research Institute (ILRI), holds a weekly town hall for the 600-plus staff of the institute as well as staff from many of ILRI partners who are hosted on ILRI campuses in Nairobi, Addis Ababa and elsewhere.

In the town hall last week, Vish Nene, co-leader of ILRI’s Animal and Human Health program, made a short presentation on the latest developments in COVID-19 vaccine work. Excerpts and slides from his virtual presentation follow.

There is good news and (you guessed it) not-so-good news regarding development of vaccines against COVID-19.

The good news

The good news is that at last count more than one hundred initiatives to develop vaccines against COVID-19. Clearly there is a mad scramble in both the academic sector and the large private pharmaceutical companies as well as small biotech companies.

The job of a vaccine is to stimulate your body to raise an immune response, either with antibody molecules or with T-cells. The job of a vaccine is to generate these responses artificially in you before you get infected with a pathogen, so that your body recognizes infection with the pathogen when it enters your body and neutralizes it so that either you are immune to the disease or suffer fewer consequences of it.

Fortunately, the CARS-CoV-2 virus is not very complicated. The particle consists of just five proteins. The genetic material instead of being DNA is RNA. A lot of work has already been done on different types of coronaviruses. So the science community knows how to go about developing a vaccine, at least to proof of principle, quite quickly.

Different vaccine development groups are taking different approaches to a vaccine against this coronavirus.

(1) ‘inactivated’ virus

(2) ‘attenuated’ virus—the virus remains infectious but doesn’t cause disease

(3) synthetic molecules derived from the virus and made chemically in the lab

(4) use of the whole viral protein—recombinant subunits—the ‘spike protein’ and put into nanoparticles

(5) use of viral genes (that is converted into RNA and then into protein)

(6) use of viral mRNA (that is converted into protein)

(7) use of viral genes inserted into attenuated vectors

Keep in mind that human and livestock vaccine development work is very similar. ILRI is currently actively exploring four of these approaches—1, 2, 4 and 7. We’ve dabbled in the past with methods in 3 and 5. The mRNA approach is something that’s new, having come about in the last 5 to 10 years, and we’re thinking about using it in our animal vaccine research.

Because of these many complementarities, we are in contact with many of the groups working now to develop a vaccine against COVID-19. We are keeping a close look at what is happening in this field.

The bottom line is that there is a race to develop a vaccine against COVD-19. Not only would a vaccine save lives but it would also not only protect people against the disease but would also obviate the social distancing restrictions most of us are now living under and ease the ongoing ‘economic lockdown’. The impacts of this pandemic not only on the global economy but also on progress towards meeting the 17 UN Sustainable Development Goals is enormous.

The not-so-good news

The not-so-good news is that a typical vaccine takes about 15 to 20 years to develop. The reason is that this is a costly enterprise. It costs somewhere between 200 and 500 million dollars to develop a vaccine. In addition, not many experimental vaccines become commercial products because they fail along various vaccine development pathways.

Development starts out in pre-clinical trials in animal models to assess the safety and suitability of an experimental vaccine for use in humans. If you get through that you get into phase 1 clinical trials in humans. The next phase, 2, tests the vaccine in much larger human groups—tens of hundreds. This is testing to see if the immune responses in these people are the kind of immune responses wanted. If you get through that you get into phase 3, which involves tens of thousands of people. Here you are testing to see if the vaccine actually protects against the disease. These phases can take anywhere from 10 to 20 years—if you’re lucky. It is to test the safety of the vaccine in humans. Regulatory review and approval processes take another two years or so.

So essentially vaccine development is a linear process, with lots of stop-go decisions along the way. Less than 10% of experimental vaccines ever make it through to commercial products.

But there’s other good news

Other good news is that the scientific and regulatory committees have developed a ‘compressed pathway’ for COVID-19 vaccines, allowing for ’emergency licensing’ procedures. But even in a best case scenario, a COVID-19 vaccine will take about 18 months to produce at large scale.

And the European Union has this week pledged about 7.5 million euros, with about half of that for development of COVID-19 vaccines and the rest for development of treatments and diagnostic tests. This should help de-risk the costs of vaccine development.

A lot of unknowns

So I think we can remain optimistic. Scientifically, we know how to make vaccines, although there are still a lot of unknowns. We don’t know whether a person will need more than one immunization. We don’t know how long that immunity will last. We don’t know whether the vaccine will be 100% efficacious or whether we will go for ‘herd immunity’.

A really good thing that is happening is that the global community has mobilized around this vaccine work. But we must keep in mind that most low- to middle-income countries don’t have the capacity for conducting this kind of vaccine research or developing or manufacturing vaccines. And a lot of questions are being asked about where a vaccine would be deployed and who would get the vaccine and when.

We really need to have these types of research activities ongoing in the world’s poorer countries, and we need the investments required for this, so that no countries are left out of the vaccine development space.

Watch Vish Nene’s 10-minute virtual slide presentation here.

Watch an earlier ILRI Town Hall presentation on ILRI’s ‘One Health’ approaches to zoonotic disease control: Global diagnosis—One Health approach necessary, 7 May 2020.