More than 30 years and 30 million deaths later, there’s still no approved HIV vaccine — a cautionary tale for anyone expecting a coronavirus vaccine within the next year, according to Kinch, a former drug developer who’s now associate vice chancellor at Washington University in St. Louis.

“There’s a built-in assumption that there will be a vaccine,” Kinch said. “We just have to go into it very sober.”

As worldwide cases surge past 750,000, governments, investors and the public are keenly watching the breakneck race to deliver coronavirus vaccines that could prevent future infections. Researchers are seen as the saviors who will deliver therapies and vaccines needed to defeat the coronavirus, and President Donald Trump has urged drugmakers to “get it done.”

Among the majority of the public, vaccines are embraced as safe and straightforward: show the virus or a key piece of it to the immune system to remember so that it’s ready when a real infection occurs. They’re typically far cheaper than drugs and can offer protection for decades, virtually for life.

But getting there is far from easy. Most vaccines go through years of tests before they hit the market; 12 to 18 months would be extraordinarily fast. The coronavirus shots moving most rapidly are made with brand-new technologies that have never proven useful in humans.

Even vaccines based on tried-and-true methods often have side effects that would limit, or prohibit, their use. Sanofi’s dengue vaccine can worsen symptoms in some people who haven’t yet been infected, restricting use, and a vaccine against Lyme disease developed by SmithKline Beecham, now GlaxoSmithKline Plc, was pulled in 2002 amid concerns about links to arthritis.

The world’s foremost experts in the field have seen the perils of predicting the arrival of a vaccine. In 1984, then U.S. Health and Human Services Secretary Margaret Heckler said a shot to prevent HIV would be ready for testing within two years. Researchers have chased that goal ever since.

Vaccine specialists this time are turning to technology aimed at speeding up a process that has traditionally taken 10 years or more. National Institute of Allergy and Infectious Diseases Director Anthony Fauci and others have predicted a coronavirus vaccine could be ready in a year to 18 months. Dozens of companies and universities around the world are pursuing a vaccine, among them Sanofi, Johnson & Johnson and Moderna Inc.

One of the front-runners, backed by the U.S. institute, is the approach used by Moderna that involves adding viral genetic material to human cells, inducing them to make proteins that spur an immune response. The U.S. company said March 16 that it treated its first patient in an early study.

The novel method is largely untested, and Holden Thorp, editor in chief of the Science family of journals, points out there are no guarantees that such messenger RNA vaccines, and others like it, will achieve their ambitious targets. Falling short could cost both society and faith in science, he said.

Double-Time

The concern is “people would get their hopes up and think that we’re going to achieve something sooner than we are, which will be demoralizing if we aren’t able to do that,” Thorp said. “Long-term, I’m worried that if science is portrayed as not coming through fast enough, that could have lasting damage.”

While similar concerns apply to new drugs, test results from Gilead Sciences Inc.’s remdesivir, first aimed at Ebola, are due next month. Regeneron Pharmaceuticals Inc. said earlier this month its efforts to develop a drug are ahead of schedule and it could start testing in humans this summer.

Vaccine makers will have to work double-time to try to hit their targets. The Coalition for Epidemic Preparedness Innovations, which has said it needs almost $2 billion to carry on coronavirus work, is funding at least eight potential vaccines. It’s already moving to set up a range of manufacturing platforms so they’ll be ready if one approach pans out, said Melanie Saville, director of vaccine research. Even if a shot is ready in the desired time frame, it probably won’t be formally approved and will only be available on an emergency-use basis, she said.

Vaccines must clear a higher bar than drugs to show they are safe because they’re injected into healthy individuals with the goal of preventing a disease that may never occur, Kinch said. Companies will likely push for exemptions from liabilities in case safety problems arise with coronavirus vaccines, and governments under pressure will probably acquiesce, he said. People should be “cautiously optimistic, with an emphasis upon the word cautious,” he said.

Still, the companies in the hunt are fueling optimism among investors, with Moderna shares gaining about 50% this year and another company relying on DNA-based technology, Inovio Pharmaceuticals Inc., more than doubling. Inovio plans to begin human trials in the U.S. in April, while Tianjin-based CanSino Biologics Inc. said this month that it received Chinese regulatory approval to start similar tests.

Catching Up

“People are way more optimistic than they should be,” said Dmitry Kuzmin, managing partner at 4BIO Capital, a London-based venture capital firm.

There are positive signs, as Kuzmin acknowledges. Drug companies are pushing ahead with different technologies, including more conventional methods, improving the odds and expanding the industry’s knowledge.

The mutation rate of the coronavirus also appears to be relatively low, unlike HIV, suggesting the pathogen could be “better behaved” and a vaccine could be durable, said Kinch, author of Between Hope and Fear: A History of Vaccines and Human Immunity. A big question is whether a shot is rendered essentially obsolete if most people are exposed to the virus before a vaccine is deployed, he said.

“I am a 100% believer in vaccines, but there’s a reality that we’re in a race against a virus and we are starting four or five laps behind,” he said. “We have to catch up.”

In the long run, an effective vaccine will likely arrive on top of therapies, but it may be intervention measures that defeat the coronavirus, said Andrew Ward, a professor and virus expert at the Scripps Research Institute. Governments around the world have imposed lockdowns and other measures in a bid to slow the spread as the death toll climbs to more than 36,000.

“This is a public health emergency, and it’s actually going to be overcome with public health measures, not with science,” he said.

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