Pijlman, a researcher at the Laboratory for Virology, is working on the development of a coronavirus vaccine as part of a European project. Two potential vaccines are being developed in the project: a Danish one and a Wageningen one. The Danish vaccine has been selected for further development: the Wageningen one is a reserve vaccine. ‘We are continuing to develop it just in case the Danish vaccine doesn’t work as well as expected,’ says Pijlman.
The Danish partner has worked fast to develop a candidate vaccine that involves producing a piece of coronavirus protein in the cells of fruit flies and then attaching it to a nanoparticle. Initial tests in mice indicate that the immune response to this vaccine is very good, says Pijlman. This vaccine has now been handed over to the EU project’s industrial partner, who is going to produce it.
The Danish vaccine will be tested in three phases over the coming months. First, a small number of people will be given the vaccine to check its safety, i.e. whether there are side effects. Then tests will be carried out on a small number of people to see whether the vaccine creates antibodies against the coronavirus. This test phase should be rounded off early next year. If the results are positive, the vaccine will then be tested in a few thousand people for safety and protection levels.
Although the Danish vaccine is highly promising, we should not count our chickens before they hatch, says Pijlman. ‘Most vaccines fail during the testing phase because they do not provide enough protection or they have severe side effects.’ For this reason, the European research group is continuing to develop the Wageningen vaccine as a Plan B.
The Wageningen vaccine is based on the spikes on the coronavirus, which are recreated by baculoviruses. This vaccine is ready too, and is now being tested on mice. WUR hope to publish the results of the tests on mice at the end of this year.
Pijlman hopes to be able to do another test in the period between the tests on mice and those on humans. ‘We want to test the Danish vaccine on macaque monkeys as well, to get a better idea of how it works, and the Wageningen vaccine will be included in those tests. Because we don’t know yet which of the two vaccines is better.’
The Dutch government has agreements with several pharmaceutical companies to buy approved vaccines from them. Does this vaccine stand a chance? ‘The government has signed six deals, which can be seen as options: if a vaccine is good, we want to buy so many millions of doses. Those agreements are not our business. Our consortium has an agreement with a pharmaceutical company, which will put the vaccine on the market.’