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Don't count on getting a coronavirus vaccine in 2021. Testing and production take time.

Vaccinations are unlikely to be widely available soon. We will still need social distancing and other ways to limit the spread of the coronavirus.

David Ridley
Opinion contributor

Many experts are saying that we can expect a COVID-19 vaccination in 12 to 18 months. They argue that the science is straightforward. The same cannot be said, though, of clinical testing and manufacturing vaccines at scale. In fact, few people will likely be vaccinated for coronavirus in 2021.

It typically takes five years to bring to market a vaccine for a new disease. Previous efforts to produce vaccines on a large scale, including a government-funded effort by Novartis to build a flu-vaccine facility, took years and hundreds of millions of dollars. Furthermore, the Novartis facility’s initial capacity was only 50 million vaccines a year —enough to serve just 15% of the U.S. population.

Rather than counting on a vaccine to quickly resolve the health and economic challenges arising from COVID-19, it’s more realistic to plan for the small supply of vaccines we’re likely to have in 2021. We should also consider how we can use the vaccine alongside strategies such as social distancing and diagnostics to limit further spread of the virus.

Outside chance of 'lab to jab' speed-up

Is there any scenario in which we could go from “lab to jab” in 18 months or less? Maybe. But it would require considerable collaboration between manufacturers and governments, concessions on safety, commitment of taxpayer dollars and a degree of good luck.

Vaccine development typically takes many years, and proving the vaccine is safe and effective in people is just the beginning. The infrastructure to make vaccines at a massive scale takes years to build. Some manufacturers may be able to use existing facilities, but that would mean delaying production of other medicines that are important for patients and profitable for companies.

To secure manufacturer commitments, governments and foundations could promise to buy a set amount of vaccine from the company with the best FDA-approved coronavirus vaccine. The Gates Foundation, for example, successfully collaborated with governments of several countries to motivate new manufacturing of a pneumococcal vaccine. Likewise, governments and foundations might pledge up front to buy a certain amount of a vaccine against COVID-19 if the vaccine can be delivered by the end of 2021.

Coronavirus vaccine testing in Kansas City, Missouri on April 8, 2020.

Such a pledge would be costly. It would take 160 million doses to supply about half of the U.S. population — the share that gets a flu vaccine each year. If the vaccine were purchased in advance at, say, $100 per dose — about half what the U.S. government pays for the human papillomavirus (HPV) vaccine —  the total price tag would come to $16 billion.

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That’s an enormous expenditure, though still far less than the current economic burden of the disease. By comparison, American taxpayers spent more than $9 billion on a hepatitis C drug in 2015.

Such commitments would be on top of small, upfront grants governments are already making to several different companies for vaccine development, including Johnson and Johnson, Moderna, Inovio and France’s Sanofi.

Vaccines might not reach most of U.S

The Sanofi effort is particularly promising, given the company’s previous experience combating Severe Acute Respiratory Syndrome, a virus that resembles the one causing COVID-19. If clinical trials go well, Sanofi expects to make 600 million doses annually of a COVID-19 vaccine.

However, even if that target were reached in 2021, it would cover less than 10% of the world’s population. And even if a manufacturer such as Sanofi could meet U.S. demand in 2021, it is not obvious that it would or should devote most of its supply to the United States.

Finally, a  previous collaboration between Sanofi and the U.S. government offers a cautionary note. Sanofi began working with federal partners on a Zika vaccine in 2016. The partnership collapsed in 2017, though, due to declining disease prevalence and haggling over price. 

A healthy return on investment would motivate developers like Sanofi to continue to devote large resources to this vaccine effort, at the expense of other worthy efforts. Yet committing money up front likely would be unpopular, and it would also come with some risk: There’s a slim chance herd immunity will develop and vaccine demand will decline, which would make a vaccine no longer necessary.

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Taken together, these manufacturing challenges suggest large-scale vaccine production is highly unlikely in the near term. Regulators would need to be comfortable with limited safety evidence. Congress would need to allocate more funding to one of America’s least popular industries. Federal officials would need to be reasonably certain that they won’t be testifying before Congress in two years about wasting billions of tax dollars on a vaccine we no longer need.

President Donald Trump just predicted a vaccine would be ready by the end of the year. However, even if the FDA approves a new vaccine, there won't be a sufficient supply to quickly vaccinate millions of Americans. Rather than assuring the public that a vaccine is coming and everyone will have access, he and other leaders should prepare for the more likely scenario — that we will have a limited vaccine supply that we must use in combination with other measures, such as social distancing, testing and treatments.

David Ridley is faculty director of the Health Sector Management program at Duke University’s Fuqua School of Business and one of the originators of the FDA Priority Review Voucher program, which created incentives for new antivirals and vaccines. He has received past funding from pharmaceutical companies and currently receives funding from public health foundations. Follow him on Twitter: @Dave_Ridley