When a vaccine for COVID-19 finally arrives, it’ll bring great relief to billions of people. But even the most dedicated scientific minds know that mass-produced inoculations are never perfect salves. As with the current flu shot, some who get pricked will get sick anyway, while others will suffer mild side effects. But what if there was a vaccine custom-made to your unique biology, one fitted for maximum effect on ailments, from cancer to coronaviruses, with minimal drawbacks?
That’s the goal of cutting-edge research into personalized vaccines — a sci-fi future that might be less than a decade away.
The problem: making vaccines more effective
Everyone’s body is unique — especially when it comes to genetics. Our genes react differently to various infections, so they also have varying responses to vaccines. For instance, studies have shown that certain vaccines recommended for older people have proven to be more effective for women than men. Other studies suggest that immune response to the flu vaccine might vary depending on ethnicity.
The solution: genetic sequencing and customized vaccines
“Trying to customize the vaccine to the individual would offer a great vaccination tool, optimized to his or her immunity response, without the side effects,” says Nicola Luigi Bragazzi, a postdoctoral fellow at Toronto’s York University who researches big data in immunology.
Customized vaccines are becoming possible because we can now know more than ever about a person’s genes. Current gene-sequencing technology can detect very small and fairly rare genetic variations — and discover which genes effect immune response.
“We can already start formulating a vaccine in months instead of years.”Nicola Luigi Bragazzi, a postdoctoral fellow at Toronto’s York University
So customized vaccines could cut down on side effects, says Bragazzi, and allow doctors to vary a vaccine’s dosage for different patients. “Some people might not respond to the standard dose and need more doses and boosters,” he explains, “while others don’t need as much.”
The challenge: cost, complexity, and an incomplete picture
As with any budding science, cost is a concern. “Customization requires a lot of studies that are time-consuming and expensive,” says Bragazzi. Humans have thousands of genes that impact the immune system and interact with each other in different ways.
But experimental immunologists are saving time and money thanks to more cost-effective DNA testing and new specialties like computational vaccinology and immunoinformatics, which use complex algorithms to evaluate huge swaths of data. Bragazzi believes the first personalized vaccines might emerge in the next decade.
Another challenge is that our genetics don’t tell the whole story when it comes to immune response. Other factors, such as age, body mass, underlying medical conditions, and even our environment and personal experiences may play a large part in how we react to vaccines.
The big picture
Bragazzi says the intense work on potential COVID-19 vaccines offers a glimpse of how the science of vaccinology is accelerating. Early in the pandemic, scientists reported that a vaccine could be available in 12 to 18 months. That might seem like an eternity to someone sheltering in place, but it would actually be an amazing feat. The standard process for developing vaccines takes up to 15 years, including years of lab research to identify an antigen, multiple phases of clinical trials, and finally, test groups of humans.
“You look at the current situation, you can see how much advancement has been done,” says Bragazzi. “The genome sequence of the virus has been obtained and made available to the entire scientific community in a short period of time. Thanks to the technology, we can already pick some candidate antigens. We can already start formulating a vaccine in months instead of years.”
Clinical trials have already begun on customized vaccines for localized or specific conditions. Bragazzi predicts the pace of vaccine development will quicken in the 2020s. “The advancement is simply amazing. In the next decade, we’ll have safer vaccines with even less side effects. And we’ll also be able to provide people with customized vaccines.”