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Medically Necessary: Delaying second doses would reshape the vaccine supply chain

This is an excerpt from the February 25, 2021 edition of Medically Necessary, a health care supply chain newsletterSubscribe here.

Good afternoon. Medically Necessary is a newsletter by Matt Blois about the health care supply chain — how we get drugs, devices and medical supplies to health care providers and patients.

Delaying second doses would reshape the vaccine supply chain

Editor’s note: An earlier version of this story incorrectly suggested that delaying vaccine doses would increase supply. It has been revised to reflect that it only increases the number of people who could receive at least one dose.

The debate: Some scientists argue the U.S. should delay second doses of COVID-19 vaccines and instead give them to people who haven’t received a shot yet, hopefully providing some protection to a greater number of people. 

  • Preliminary data from the U.K. and Israel suggest a single dose of Pfizer’s vaccine provides good, but not perfect, protection from COVID-19. This strategy hasn’t been tested in randomized, controlled trials, so there’s lots of uncertainty.

If the U.S. decided to delay second doses, vaccine clinics would still administer the same number of shots. It wouldn’t increase the supply directly, but would reshape how the vaccine is distributed.

  • “It doesn’t increase the efficiency. It changes the distribution pattern of the vaccine. But it does in essence double the number of people that can have the first vaccination,” Mark Sawicki, CEO of the cold chain logistics company Cryoport Systems, told FreightWaves in early February. 

The backstory: The federal government initially planned to hold back a reserve of COVID-19 vaccines to ensure second doses would be available on time. By January, the federal government had started releasing second doses to boost vaccine supply. (This change happened before the policy was announced, confusing many state officials.) 

Though the federal government stopped reserving doses, it has always aimed to deliver the second dose of the vaccine on time — three or four weeks after the first shot. 

U.K. officials decided in December to delay the second dose of the AstraZeneca and Pfizer vaccines to get more people vaccinated. 

Planning ahead: Right now, most vaccine clinics know how many doses they will receive over the next three weeks, according to Prashant Yadav, a supply chain researcher at Harvard Medical School. 

  • “It’s just about at that level where second doses can be reserved … [with] incoming supply,” Yadav wrote in an email.

From a purely supply chain standpoint, postponing second doses means planning for them slightly farther out in the future. Without visibility into the future of the vaccine supply that could be very difficult.

In general, the vaccine supply has increased steadily since the start of the rollout, meaning it’s usually a safe bet for vaccine clinics to assume they’ll have more doses in the future. But it doesn’t always work out that way. The recent winter storm has caused widespread delays of COVID-19 doses across the country. 

With an emergency use approval for Johnson & Johnson’s COVID-19 vaccine on the horizon (keep reading) and indications that Moderna and Pfizer are accelerating production (keep reading), vaccine administrators may soon have more predictability.  

Will it happen? So far, U.S. officials haven’t shown much enthusiasm for delaying second doses.

The Biden administration’s COVID-19 Strategy says the White House is exploring “dose-sparing strategies that have the potential to substantially expand vaccine supply,” but White House officials have also said there’s not enough data to support delaying second doses.

Earlier this week, National Institutes of Health Director Francis Collins wrote a blog post expressing some optimism about giving a single shot to people who have already recovered from COVID-19, based on early data showing that they have an especially strong immune response.

  • “Such a policy is already under consideration in France and, if implemented, would help to extend vaccine supply and get more people vaccinated sooner. But any serious consideration of this option will require more data,” Collins wrote.  

Johnson & Johnson close to emergency approval

A Johnson & Johnson scientist in Leiden, The Netherlands. (Credit: Johnson & Johnson)

A new COVID-19 vaccine from Johnson & Johnson is close to receiving emergency approval from the U.S. Food and Drug Administration. 

  • An FDA analysis released this week found that the company’s vaccine is safe and effective. An FDA community will meet on Friday to determine whether the data warrant an emergency approval. 

Logistically easier: The Johnson & Johnson vaccine will be much easier to distribute. The vaccine is administered in a single dose, compared to two shots for both vaccines currently approved in the U.S.

The Johnson & Johnson vaccine also has less rigorous temperature requirements for transportation and storage. It has a shelf life of three months when stored at normal refrigeration temperatures, about 36 to 45 degrees Fahrenheit.

  • Moderna’s vaccine must be shipped at minus 4 Fahrenheit, and Pfizer’s must be shipped and stored at minus 94 Fahrenheit.

Ready to go: During a press briefing on Wednesday, White House COVID Coordinator Jeff Zients said he had recently updated governors on plans to distribute the vaccine. 

He said the U.S. would use the same allocation process for the Johnson & Johnson vaccine that it’s using for the current vaccines.

  • “We will waste no time getting this lifesaving vaccine into the arms of Americans,” Zients said.

Analysts predict a big boost in vaccine supply


Prepare for liftoff: Executives from Pfizer, Moderna, Johnson & Johnson, AstraZeneca and Novavax all reported mostly good news earlier this week during a congressional hearing about vaccine production.

  • Pfizer expects to ship more than 13 million doses per week by the middle of March, up a whopping 160% since early February.
  • “We have doubled our monthly deliveries since late 2020, and we are aiming to double them again by April to more than 40 million doses per month,” Moderna President Stephen Hoge told lawmakers in written testimony.
  • Johnson & Johnson plans to deliver 20 million doses by the end of March if it receives emergency approval for its vaccine. That’s a welcome boost, but it’s far below the company’s initial production target, according to The New York Times.
  • AstraZeneca noted that U.S. manufacturing plants are running at full capacity and aren’t experiencing any material or equipment constraints. The company added that the Defense Production Act has sped things up.
  • Novavax says it can deliver 110 million doses to the U.S. by the third quarter of 2021. By the middle of this year, the company says it can produce 150 million doses per month for distribution across the world.

Based on those reports, and previous company statements, analysts at Bloomberg are predicting a major increase to vaccine supply over the coming weeks. Bloomberg predicts the U.S. is on track to deliver 4 million doses per week by April, up from 1.6 million in mid-February.

Reading list: The best stories about the health care supply chain

  • “Feds OK’d Export of Millions of N95 Masks as U.S. Workers Cried for More” Kaiser Health News
  • “Novavax Nears Covid-19 Vaccine Game Changer — After Years of Failure” The Wall Street Journal
  • “Pakistan’s Polio Playbook Has Lessons For Its COVID-19 Vaccine Rollout” NPR

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Matt Blois