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Merck Bets On a One-Shot Vaccine in Race With Its Faster Rivals
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New Merck COVID Efforts-2 Vaccines+Antiviral Drug EIDD-2801; Acquisition & Collaborations - (05/26/20)
America's top vaccine maker has kept a low profile during the pandemic but says convenience will be its advantage.
August 10, 2020, 1:00 PM EDT
https://www.bloomberg.com/news/articles/2020-08-10/covid-vaccine-don-t-count-merck-out-of-the-race-just-yet
In the race for a Covid-19 vaccine, Merck & Co. looks slow. The drugmaker formally announced its plans just after Memorial Day, shortly before America's death toll from the coronavirus passed 100,000. It says human trials of one of its shots will begin in mid-August, months behind the likes of AstraZeneca, Moderna, and Pfizer, whose vaccines have already begun large-scale testing. Pfizer has said it could approach regulators for an emergency use authorization as early as October. Merck told Congress last month that 2021 is the absolute earliest it expects to have a vaccine ready, and its top executives have cast doubt on the rosier predictions being made for other shots.
Suggesting that any vaccine candidate might be broadly available before the end of the year does the public a disservice, according to Merck Chief Executive Officer Kenneth Frazier. No successful vaccine has ever been developed and approved in under four years, a record Frazier's company set in the 1960s. Merck's pace, the CEO said in May, is deliberate, not flat-footed. "It's not that we couldn't have done something earlier," he said, sounding ever so slightly defensive. "My colleagues have been working on this since the time coronavirus was first heard of, but they've taken their time and been very conscientious about which programs they think could make a difference over the long term."
It's never wise to count Merck out of the quest for a vaccine. The company's century of success includes some of the first U.S. inoculations for measles, mumps, rubella, and chickenpox. Most American kids now get Merck-produced vaccinations for all four. The company has pioneered vaccines for HPV, in 2006, and Ebola, last December. "They're 'slow and steady wins the race' kind of guys," says Jonathan Miller, an analyst at research firm Evercore ISI.
This time, Merck is betting that people won't mind a later vaccine if it's more powerful and more convenient. Most coronavirus vaccines require two doses—a vaccine plus a booster shot—to elicit a strong enough immune response. Roger Perlmutter, Merck's top scientist, says his team is working to get it done in one go. It's an audacious goal, one that's far from guaranteed to work. Johnson & Johnson is one of the few others that have announced plans to test a single-dose regimen in large trials, but J&J is trying multidose regimens, too.
What's more, no U.S. front-runner is attempting a lab strategy like Merck's: using vaccines based on weakened viruses that replicate in the body but don't cause disease. This is the kind of old-school approach the company has relied on for decades, now augmented with genetic engineering to add Covid-specific proteins or RNA. One test shot is based on a measles vaccine used in Europe. Another borrows technology from Merck's Ebola injection and is being developed in partnership with the International AIDS Vaccine Initiative (IAVI), which has experience with similar research.
In debating how to have the maximum impact on Covid-19, Merck was guided by one major principle, says Daria Hazuda, a biochemist and Merck's vice president for infectious diseases discovery. "We needed to have a global solution," she says. That meant a vaccine that's simple to administer, easy to distribute, and relies on "tried and true" technology to generate a rapid immune response. This ruled out newer approaches like messenger RNA, she says.
Merck licensed the Ebola shot, developed by researchers in Canada and elsewhere, in 2014 while it was still in early human trials. The company picked a winner. A giant trial conducted in the West African country of Guinea and published in 2016 showed that a single dose was 100% effective at preventing Ebola in people who had close contact with infected patients. And it began working in an extraordinarily rapid time, a week to 10 days. "If you are thinking about a vaccine you want to use to contain an outbreak, those are the attributes you would want," says Mark Feinberg, a former Merck executive who runs IAVI.
The Ebola vaccine is a more complicated piece of engineering than the messenger RNA vaccines formulated by Moderna Inc. and Pfizer Inc., which are basically strands of genetic material encased in protective fatty particles. It's based on a vesicular stomatitis virus, or VSV, which causes diseases in horses and cows but not humans. Proteins for human diseases can be bound to its surface, but it's taken researchers months to tweak Covid-19's distinctive spike protein so it properly joins VSV to form immune-stimulating virus particles. In the best-case scenario, Merck researchers might be able to produce a liquid Covid-19 vaccine that patients can just swish around their mouths and swallow. But the VSV-based vaccine isn't expected to reach clinical trials until fall.
The modified measles virus vaccine is moving faster. In May, Merck agreed to buy Themis Bioscience, an Austrian biotech company that held the rights to underlying technology first developed by the Institut Pasteur in Paris, for an undisclosed sum. The technology encodes genetic data for coronavirus spike proteins inside the measles particle, which Merck says might also offer a one-shot solution. "I don't think there's any other vaccine that has the track record of safety that this one has," says Hazuda. The Trump administration is still looking to secure stockpiles of vaccines using old-school techniques in this vein, according to Moncef Slaoui, chief advisor to the administration's vaccine development program. Merck says it plans to begin a 260-person trial on Aug. 19.
Of course, if the speedier two-shot trials prove successful, many people might not wait for Merck's single dose. And once competing shots are on the market, it might be tougher for Merck to enroll patients in large studies. As Frazier has warned, though, every step along the path to billions of inoculations could take longer than hoped. In the meantime, his company has licensed a promising antiviral drug to treat Covid-19 symptoms—one that will be taken in pill form in late-stage trials starting next month. The drug has already shown in lab tests that it alleviates symptoms from other coronaviruses. Here, too, Merck is planning conservatively. "This is not our last pandemic," Perlmutter said in a July 31 call with investors. "And probably not the last pandemic caused by a coronavirus".
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