Just a month has passed since Chinese scientists decoded the genetic information of the coronavirus SARS-CoV-2 and made it available to the global research community. Numerous research-based pharmaceutical companies, universities and other research institutions then immediately got to work.
In the meantime, the number of labs working at full speed on the development of a vaccine to combat SARS-CoV-2 has grown to such an extent that it is difficult to maintain an overview.
In addition to the large research institutes, such as the National Institute for Viral Control and Prevention in mainland China, researchers in Hong Kong, the USA, Germany, France, Australia, Canada and Israel are busy developing vaccines.
Read more: Coronavirus vaccine — a race against time
Several projects are financially supported by CEPI, an international partnership to combat epidemics, which is financed by government and private funding. This partnership is currently funding vaccine developments by CureVac (here in Germany) and Inovio and Moderna (both in the US). In addition, there's a project at the University of Queensland (Australia), which has been testing a vaccine in animal models since the end of February.
The CEPI projects are also supported by the US companies Dynavax and Glaxo Smith Kline (GSK), which are involved in the development of something called adjuvants. These work kind of like amplifiers in that they ensure that fewer antibodies per vaccine dose are sufficient to induce an immune response.
In addition to the CEPI projects, Johnson&Johnson, Novavax (both in the US), Sanofi (France and multinational, respectively) and the Canadian VIDO-InterVAC have announced their own vaccine developments.
Some research groups have announced that they'll accelerate vaccine development by setting very ambitious schedules, sometimes as short as a few weeks.
German experts, however, view such announcements very critically. Infection epidemiologist Dr. Alexander Kekulé, who heads the Institute of Medical Microbiology at the University Hospital in Halle, assumes that an approved vaccine could be launched on the market in 2021 at the earliest.
"There is no way we'll have a vaccine by autumn ," the professor of medicine said during a debate on German public television.
Kekulé also explained that developing a vaccine against coronaviruses is particularly difficult, because coronaviruses are genetically very mutable.
This idea is supported by a study conducted by Chinese scientists, who have now discovered that there are already two SARS-CoV-2 strains, an s-CoV and an l-CoV strain. The first of these is the more common, the second more dangerous.
The rapid mutability of the coronaviruses is also one of the reasons why there are no vaccinations against the common, seasonal cold viruses. At least yet. Most of these cold viruses are also coronaviruses, albeit far more harmless than SARS-CoV-1, SARS-CoV-2 or MERS.
Safety before speed
In contrast to the Ebola virus, for example, where phases II and III of the vaccine launch were both combined, an accelerated approval procedure for SARS-CoV-2 is out of the question.
This is because the coronavirus is much less dangerous than Ebola, and the urgency is therefore not as great.
The introduction of a vaccine always means that many healthy people will have to be vaccinated with it. And here — unlike with Ebola — the risk assessment clearly argues against a hasty procedure.
"You never know exactly what you'll find when you do your testing,” says Dr. Rolf Hömke of the association of research-based pharmaceutical companies in Germany. "So a company which takes a little longer with designing a vaccine may take a little shorter with the testing.”
It is more important to rule out any possible damage that a vaccine itself could cause to a person than to vaccinate healthy individuals who almost never suffer from a severe form of COVID-19.
In addition, there are already drugs available to treat the severe progressions of the disease after an individual contracts it. The RNA polymerase inhibitor Remdesivir, for example, which was originally developed against Ebola and has already been launched on the market, is very promising.
How will the different vaccinations work?
Almost all vaccines under development are based on pre-existing vaccines. Doctors call this "platform development.” Some of them are already in use in veterinary medicine, such as a vaccine against MERS, which is already used for camels. Also, some vaccines have already been tested in animal models or are about to be tested.
The hopes of some pharmaceutical companies are currently pinned on vaccines whose genetic information (mRNA or DNA) causes the formation of harmless viral proteins in the body. The body's immune defense system is then supposed to react to it.
This approach, which Hömke says has never been approved before, would work, at least in theory, by taking a few genes from the coronavirus and transforming them into a vaccination.
"When people get vaccinated from that, they will produce parts of the coronavirus within their body,” he told DW. "And this actually causes their immune system to start producing antibodies against it. So that's a totally different approach, something that has so far never been approved — it's too new — but may be a way to get the vaccine ready even quicker than with the other approaches.”
"Another approach is a bit more conventional,” Hömke explains. "Take the coronavirus, and de-arm it. Inactivate what is in that virus that makes you ill, to end up with a virus which can infect, but not make you will, and may be suitable for vaccination.”
This is a rather traditional method of vaccine production. However, it can take longer before sufficient vaccine doses are delivered.
Finally, a third path involves taking a totally different virus and dressing it up in "corona clothes,” Hömke says, so that it appears as a coronavirus to the human body. This, too can be used to vaccine against SARS-CoV-2.
In principle, it cannot be ruled out that a vaccine will only become available after the current pandemic has abated. However, it is also possible that further COVID-19 waves will continue to ripple around the globe.
If summer begins in the northern hemisphere and the viruses have a harder time, epidemics could then break out in the colder southern hemisphere. Then, from late autumn onward, the virus could then spread more easily in the north again.