This week, in a wide-ranging interview with The New Daily, Professor Peter Doherty, Nobel Laureate and immunologist, talked about the likelihood of a vaccine for COVID-19 being developed, and what happens if we don’t get one.
The short answer is that COVID-19 might have to be contained in the same way that HIV has been brought under control, via a daily drug regimen.
The following are edited extracts from episode four of The COVID Conversation podcast for which the interview was recorded.
Regarding the likelihood of a vaccine
“I think we will get an effective vaccine. I would be very surprised if we don’t. We’ve got something like 70 different candidates out there. The only issue with a vaccine is safety as far as l’m concerned. I think we’ll get a vaccine that makes a good immune response. I think we’ll get a vaccine that stops infection.
“But there are some hints from earlier studies with monkeys that some types of immune response can actually make the disease worse. So we want to avoid those effects. And it’s a bit problematic with this virus because, unlike SARS, it doesn’t grow nearly as well in monkeys. We don’t have as good a test system.
“At some point, some people are going to have to go out there with a vaccine and put themselves in the way of the infection. And just hope that it works.”
How a vaccine might require more than one jab:
“What we may be looking at with vaccines, for instance, is we prime with one vaccine. And a month later we come back and boost with another one. That may be very important especially with older people who don’t make such good immune responses.
“But there will always be an issue with people, even if we’ve got a good vaccine, with people who make very bad immune responses. That may be due to age or it could be to do with the fact they have a damaged immune system.
“So the other way to get around this is to have anti-viral drugs.”
Adopting the HIV strategy
“Anti-viral drugs could be used for therapy or for prevention (of COVID-19).
“With HIV, we never made a vaccine. The virus mutates too much. It copies back into the genome. A vaccine is almost impossible … So we handle it with drugs. What an AIDS patient does is take two or three drugs a day …These were drugs that were made from knowing the structure of (viral) proteins: structural biologists designed molecules that would fit those proteins and stop them (from acting destructively). AIDS patients take three different drugs. The reason they do that is to stop mutants emerging … Same principle you use in cancer therapy.
“So those drugs that will keep AIDS down can also be used as what we call PReP (pre-exposure phrophylaxis). And that is, people who put themselves at risk of AIDS can take a drug called Truvada which has two of these anti-viral AIDS drugs that are also used for treatment. And if they take those every day they’re just not going to get AIDS.
“So, if we can find drugs that eliminate (the coronavirus) early on, that may stop the late disease. If we can treat them and they don’t die, we can open up and treat it like any other infection. As long as we have treatment we’re fine.
“If we have people who can’t benefit from a vaccine, or if we can’t get a vaccine, we could use the equivalent of HIV PRep. Everybody could take a pill every day which would stop them getting the infection. For older people, that’s nothing. They all take four or five pills a day, anyway. So that’s the other possibility.
“And you can bet your life there are a hell of a lot of people working on drug development.”
In the COVID Conversation podcast, Professor Doherty speaks at length about why our immune system so often lets us down; the questions raised by the many people who have been infected with COVID-19 but remain asymptomatic; the inevitable reliance on China to manufacture vaccine doses by the billion and why it’s against our interests to engage in China bashing. And more. To hear the entire interview, see here.
Professor Doherty writes a weekly column, in which he explains the basics of immunology, viruses and where science words come from.