They are the size of large kitchen refrigerators, consume a lot of electricity and keep things very, very cold.
LifeBridge Health ordered three of these ultra-low temperature freezers about four weeks ago in anticipation of approvals for the first COVID-19 vaccines. That includes one from the drug maker Pfizer, a frontrunner in the race to market, which reported promising data Monday on its high level of effectiveness.
“We ordered them and are waiting for them to come,” said Lisa Polinsky, assistant vice president of pharmacy services for Lifebridge Health, which operates Sinai Hospital in North Baltimore, Northwest Hospital in Randallstown and Carroll Hospital in Westminster. "These types of freezers aren’t something used all that often.”
The freezers, which can hold about 4,000 doses each and cost between $10,000 and $20,000, are part of a larger, complex logistical distribution effort for potential vaccines from Pfizer or Moderna, which have both been tested in Maryland. But they represent among the biggest potential physical hurdles for distribution.
The need for deep freeze will require extra planning, now and as front line workers and then others line up for vaccination.
Pfizer acknowledged the challenge Monday from its vaccine’s “ultra-low temperature formulation” at the same time it released preliminary data showing the vaccine it’s developing with BioNTech is more than 90% effective in preventing COVID-19, the illness caused by the coronavirus.
That’s far higher than expected, and well above the 50% bar set by federal regulators.
Pfizer said the vaccine needs to be shipped in dry ice, stored at minus 70 degrees Celsius and refrigerated for only short periods at distribution sites.
Health departments, hospitals and others tapped to distribute vaccines don’t typically have these freezers, except for research purposes. Most vaccines require only refrigeration.
There are not enough of them, nor likely stocks of dry ice for shipping vaccines to so many different places where they will be needed, said Dr. Georges C. Benjamin, executive director of the American Public Health Association.
“It’s not a unknown logistical issue," said Benjamin, pointing to lack of refrigeration and other infrastructure in developing countries. "Having said that, the big issue is not how to move vaccines across the country by major shippers. It is how to move it from them to pharmacies, retail clinics, doctors offices, etc., and maintain the ultra cold environment.”
The number of such freezers on hand or expected in the state isn’t publicly known. The Maryland Department of Health is tracking capacity in a “confidential database of facilities and organizations,” according to Charles Gischlar, an agency spokesman.
“Ultra-cold vaccine storage is not a routine storage temperature for vaccines and poses challenges to maintaining proper temperatures,” Gischlar said. “The shipping containers that the ultra-cold vaccine will be shipped in can also be used as temporary storage units, so we are not strictly limited to those sites that have [ultra-cold] capacity.”
Hospitals have been planning for weeks, ordering freezers, as well dry ice for shipping, and planning how clinics would work.
At the same time, vaccines have moved closer to an emergency use authorization by the U.S. Food and Drug Administration, a temporary approval that requires continued study by manufacturers that have been moving at unusually great speed to develop vaccines.
The approvals may not be far off, said Dr. Kathleen Neuzil, director of the University of Maryland School of Medicine’s Center for Vaccine Development and Global Health. The center participated in early phase clinical testing of the Pfizer vaccine and is conducting late stage testing of the Moderna one.
Neuzil called the efficacy data from Pfizer “remarkable,” but said it likely would take a couple of more weeks to get enough data to the FDA. The agency will review safety, possible side effects and other risks for different groups of people and the benefits.
She said Pfizer and Moderna will continue work on new formulations that might not need a deep freeze or even a second dose like their initial vaccines will.
“Normally, manufacturers have years to work out these issues for optimal formulation,” Neuzil said. “The storage requirement will make this formulation much more challenging than a typical influenza vaccine.”
Both the Pfizer and Moderna vaccines are mRNA vaccines, which start with a bit of genetic material from a “spike” protein found on the coronavirus. The code is injected into a person’s muscle cells, where it is read and reproduced. When the body recognizes this as a foreign invasion, it produces antibodies in defense. The antibodies then also block a real coronavirus infection.
Drug makers will not only have to work on formulations that don’t need such cold temperatures, but versions that work on different people, said Andrew Pekosz, a Johns Hopkins professor of molecular microbiology and immunology. Like flu vaccines, they could be made to address age, weight or other variables.
In the meantime, there are likely to be some doses wasted, he said. That’s because they may not work as well on some people. But also, because of the challenges of keeping the doses so cold.
“In the beginning I imagine we’ll see a few sites giving out vaccines to high priority individuals,” Pekosz said.
That will be fairly straight forward, with hospital workers getting shots in their own hospitals, he said. Vaccinating in nursing homes will be fairly simple, too, as there are specific numbers of people living there and needing vaccines, making shipping predictable.
Other groups may have to be vaccinated on strict schedules so doses don’t have to be shipped when there is a chance they will not be used before they defrost.
Dry ice used for shipping to clinics or doctors' offices or elsewhere, evaporates quickly, offering a tight window for distribution unless it’s replaced. Pfizer said doses of its vaccine can last two days in refrigeration after being removed from deep freeze, though some experts say it’s likely less.
The mRNA vaccines will always require some level of cold, Pekosz said. That’s why hospitals are buying freezers, including the largest hospital systems in the state: MedStar Health, with 10 hospitals in Maryland and Washington, D.C., and the University of Maryland Medical System, a 13-hospital system.
The Maryland system has purchased four freezers “that will be located at strategic locations throughout our system in several different counties and Baltimore City for the purpose of vaccine storage," officials there said.
The system also contracted with a vendor to supply a pellet type of dry ice recommended for use to refill the shipping containers.
Some vaccines in Maryland and around the country may stay on dry ice in those shipping containers on trucks because there won’t be enough freezers, according to the Association of State and Territorial Health Officials.
That may be particularly true in more rural areas with less freezer capacity, said Tinglong Dai, an associate professor of operations management and business analytics in Hopkins' Carey Business School. He said it also may be necessary to bring in health care professionals along with vaccines to ensure there are enough vaccinated workers to give out shots.
He speculated on specific methods to bring vaccines where ultra-cold freezers are not available. One involves shipping vaccines in cooling boxes through major airports and onto trucks that bypass warehouses or storage and go directly to administration sites where people have appointments. Those people could be notified by when their first or second dose arrives.
Drone delivery could be another option, he said, though that potential remains under review by federal officials.
All this planning is in the works, based on guidance from the state health department and the U.S. Centers for Disease Control and Prevention, he said.
“Overall,” Dai said, “I feel cautiously optimistic that we will have a smooth delivery due to all the efforts made in the past months.”