As Covid-19 brought nearly every corner of the Earth to a halt early last year, researchers around the world scrambled to develop a vaccine to fend off the deadly respiratory coronavirus. And just several months later — in a process that normally takes years — several vaccines were ready for worldwide distribution.
In comparison, about 40 years since the earliest reports of what became known as AIDS, scientists are still scratching their heads to develop a vaccine against the virus that causes the life-threatening disease — HIV.
But as the anniversary of the first Covid-19 vaccine shots approaches, experts say the brisk development of the lifesaving and highly effective coronavirus vaccines may have brought researchers closer to cracking the code to develop an HIV vaccine.
“There’s a lot of new energy and buzz among scientists looking at how quickly some of the Covid science got done,” said Rowena Johnston, the vice president and director of research at amfAR, an international nonprofit AIDS research group. “I think there’s been a lot of soul-searching about how the scientific enterprise can be improved so that we can better serve the people we’re trying to help.”
Before the coronavirus vaccines, the most rapidly developed vaccine ever created — from sampling to deployment — was for the mumps in the 1960s. The process took about four years.
The federal government has conducted five large-scale Phase 3 HIV vaccine trials, all of which have failed. Its third Phase 3 trial was notable for increasing the likelihood of HIV infection among those who were vaccinated.
Scientists largely blame HIV’s unrelenting evolution inside the body.
“The scale of mutations that HIV produces are beyond anything that’s even in the same realm of what coronavirus does,” Johnston said. “If you mapped out a genetic tree of all the different variants of HIV inside the body of one person, it’s about as equivalent of all the genetic variations of all the influenza virus of all people around the world during one year.”
Therefore, HIV is always one step ahead of the antibody response that failed vaccines trigger in the body, said Dr. Ronald Desrosiers, a professor at the University of Miami’s Miller School of Medicine, who was one of the first scientists to study SIV — the monkey disease from which HIV is thought to have originated.
“The antibodies that’s present in a person can neutralize the virus that was present three months ago, but it can’t neutralize the virus that’s replicating at the current time,” Desrosiers said. “It would be predicted to make development of a vaccine very, very difficult, and those predictions have come true.”
But however elusive an HIV vaccine may be, scientists — including Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases and the chief medical adviser to the president — say it is “likely” that one could develop from the pioneering technology used to make coronavirus vaccines.
Two of the coronavirus vaccines, those made by the pharmaceutical companies Pfizer-BioNTech and Moderna, were the first vaccines ever to successfully trigger immune responses using messenger RNA, or mRNA, a genetic material that our cells read to make proteins. The mRNA coronavirus vaccines have proven to be more effective at fending off the virus than the Johnson & Johnson vaccine, which resembles more traditional influenza vaccines and does not use mRNA.
Moderna announced in August that it would soon launch a Phase 1 clinical trial for two new mRNA-based HIV vaccines, giving scientists fresh hope.
“If it were just another way to deliver the vaccine ingredients, I would say it would probably have no chance of succeeding where others have failed,” Johnston said.
However, what has piqued Johnston’s interest is that the mRNA coronavirus vaccine is delivered in the body through its lipid nanoparticles. Johnston said the lipid nanoparticles not only help deliver the drug but also act as an adjuvant, a substance that helps strengthen a drug’s effect. And in this case, the adjuvant stimulation effect is working at “a greater extent than any conventional vaccine,” she said.
“When I learned that, it really did give me some hope that finally we have a really, truly a new concept to test in HIV,” she said. “So let’s put our optimistic hats on and hope that this might be the thing that gets us over the finish line.”
Aside from the scientific advancements it sparked, some experts say, the coronavirus pandemic may also indirectly help the HIV vaccine effort by generating more interest in science.
“The world has now increased its scientific literacy. I think the opportunity to build on that in HIV and make people more vaccine-aware and engage in vaccine research and introduction has grown exponentially,” said Mitchell Warren, the executive director of AVAC, a nonprofit organization promoting global HIV treatment.
But others worry that the enthusiasm to stave off the coronavirus pandemic may have come at a cost to HIV research.
When the pandemic pummeled the globe last year, many of the world’s leading HIV researchers shifted gears to the coronavirus. For instance, Johnson & Johnson tapped Dr. Dan Barouch of Harvard Medical School, who has studied HIV for over 15 years, to help develop its coronavirus vaccine.
Overall, scientists who did not pursue Covid-19-related research initiated 36 percent fewer new projects last year compared to 2019, according to a study by Northwestern University that was published in October.
“Sometimes people chase the exciting new thing, they follow the dollars. But we need to get people back to HIV, or there will be a price,” said the director of the Infectious Diseases Initiative at Georgetown University, Jeffrey S. Crowley, a former director of the White House Office of National AIDS Policy.
Regardless of whether the coronavirus will lead to scientific improvements or setbacks, some scientists say defeating HIV will rely more heavily on commonsense global health practices.
“Any pandemic is a day away, and we sort of learned that initially with HIV, but this pandemic has brought that home in an extremely strong way,” said Dr. Kenneth Mayer, a Harvard Medical School professor who is the medical research director of Fenway Health. “What happens in one part of the world doesn’t stay in that part of the world.”