Biomedical engineer Kevin Zhao has a sensor in his arm and his chest that monitors his oxygen level in those tissues in real time.
Last month, at a conference celebrating DARPA, the research arm of the Defense Department, FBI Special Agent Edward You declared, "The 21st century will be the revolution of the life sciences."
Biomedical engineer Kevin Zhao has a sensor in his arm and chest that monitors his oxygen level in real time.
Indeed, four years ago, the agency dedicated a new office solely to advancing biotechnology. Its primary goal is to combat bioterrorism, protect U.S. forces, and promote warfighter readiness. But its research could also carry over to improve health care for the general public.
With an annual budget of about $3 billion, DARPA's employees oversee about 250 research and development programs, working with contractors from corporations, universities, and government labs to bring new technologies to life.
Check out these three current programs:
1) IMPLANTABLE SENSORS TO MEASURE OXYGEN, LACTATE, AND GLUCOSE LEVELS IN REAL TIME
Biomedical engineer Kevin Zhao has a sensor in his arm and his chest that monitors his oxygen level in those tissues in real time. With funding from DARPA for the program "In Vivo Nanoplatforms," he developed soft, flexible hydrogels that are injected just beneath the skin to perform the monitoring and that sync to a smartphone app to give the user immediate health insights.
A first-in-man trial for the glucose sensor is now underway in Europe for monitoring diabetics, according to Zhao. Volunteers eat sugary food to spike their glucose levels and prompt the monitor to register the changes.
"If this pans out, with approval from FDA, then consumers could get the sensors implanted in their core to measure their levels of glucose, oxygen, and lactate," Zhao said.
Lactate, especially, interests DARPA because it's a first responder molecule to the onset of trauma, sepsis, and potentially infection.
"The sensor could potentially detect rise of these [body chemistry numbers] and alert the user to prevent onset of dangerous illness."
2) NEAR INSTANTANEOUS VACCINE PROTECTION DURING A PANDEMIC
Traditional vaccines can take months or years to develop, then weeks to become effective once you get it. But when an unknown virus emerges, there's no time to waste.
This program, called P3, envisions a much more ambitious approach to stop a pandemic in its tracks.
"We want to confer near instantaneous protection by doing it a different way – enlist the body as a bioreactor to produce therapeutics," said Col. Matthew Hepburn, the program manager.
So how would it work?
To fight a pandemic, we will need 20,000 doses of a vaccine in 60 days.
If you have antibodies against a certain infection, you'll be protected against that infection. This idea is to discover the genetic code for the antibody to a specific pathogen, manufacture those pieces of DNA and RNA, and then inject the code into a person's arm so the muscle cells will begin producing the required antibodies.
"The amazing thing is that it actually works, at least in animal models," said Hepburn. "The mouse muscles made enough protective antibodies so that the mice were protected."
The next step is to test the approach in humans, which the program will do over the next two years.
But the hard part is actually not discovering the genetic code for highly potent antibodies, according to Hepburn. In fact, researchers already have been able to do so in two to four weeks' time.
"The hard part is once I have an antibody, a large pharma company will say in 2 years, I can make 100-200 doses. Give us 4 years to get to 20,000 doses. That's not good enough," Hepburn said.
To fight a pandemic, we will need 20,000 doses of a vaccine in 60 days.
"We have to fundamentally change the idea that it takes a billion dollars and ten years to make a drug," he concluded. "We're going to do something radically different."
3) RAPID DIAGNOSING OF PATHOGEN EXPOSURE THROUGH EPIGENETICS
Imagine that you come down with a mysterious illness. It could be caused by a virus, bacteria, or in the most extreme catastrophe, a biological agent from a weapon of mass destruction.
What if a portable device existed that could identify--within 30 minutes—which pathogen you have been exposed to and when? It would be pretty remarkable for soldiers in the field, but also for civilians seeking medical treatment.
This is the lofty ambition of a DARPA program called Epigenetic Characterization and Observation, or ECHO.
Its success depends on a biological phenomenon known as the epigenome. While your DNA is relatively immutable, your environment can modify how your DNA is expressed, leaving marks of exposure that register within seconds to minutes; these marks can persist for decades. It's thanks to the epigenome that identical twins – who share identical DNA – can differ in health, temperament, and appearance.
These three mice are genetically identical. Epigenetic differences, however, result in vastly different observed characteristics.
Reading your epigenetic marks could theoretically reveal a time-stamped history of your body's environmental exposures.
Researchers in the ECHO program plan to create a database of signatures for exposure events, so that their envisioned device will be able to quickly scan someone's epigenome and refer to the database to sort out a diagnosis.
"One difficult part is to put a timestamp on this result, in addition to the sign of which exposure it was -- to tell us when this exposure happened," says Thomas Thomou, a contract scientist who is providing technical assistance to the ECHO program manager.
Other questions that remain up in the air for now: Do all humans have the same epigenetic response to the same exposure events? Is it possible to distinguish viral from bacterial exposures? Does dose and duration of exposure affect the signature of epigenome modification?
The program will kick off in January 2019 and is planned to last four years, as long as certain milestones of development are reached along the way. The desired prototype would be a simple device that any untrained person could operate by taking a swab or a fingerprick.
"In an outbreak," says Dr. Thomou, "it will help everyone on the ground immediately to have a rapidly deployable machine that will give you very quick answers to issues that could have far-reaching ramifications for public health safety."
Tardigrades can completely dehydrate and later rehydrate themselves, a survival trick that scientists are harnessing to preserve medicines in hot temperatures.
Formulating biologics to withstand drying and hot temperatures has been the holy grail for pharmaceutical researchers for decades. It’s a hard feat to manage. “Biologic pharmaceuticals are highly efficacious, but many are inherently unstable,” says Thomas Boothby, assistant professor of molecular biology at University of Wyoming. Therefore, during storage and shipping, they must be refrigerated at 2 to 8 degrees Celsius (35 to 46 degrees Fahrenheit). Some must be frozen, typically at -20 degrees Celsius, but sometimes as low -90 degrees Celsius as was the case with the Pfizer Covid vaccine.
For Covid, fewer than 73 percent of the global population received even one dose. The need for refrigerated or frozen handling was partially to blame.
The costly cold chain
The logistics network that ensures those temperature requirements are met from production to administration is called the cold chain. This cold chain network is often unreliable or entirely lacking in remote, rural areas in developing nations that have malfunctioning electrical grids. “Almost all routine vaccines require a cold chain,” says Christopher Fox, senior vice president of formulations at the Access to Advanced Health Institute. But when the power goes out, so does refrigeration, putting refrigerated or frozen medical products at risk. Consequently, the mRNA vaccines developed for Covid-19 and other conditions, as well as more traditional vaccines for cholera, tetanus and other diseases, often can’t be delivered to the most remote parts of the world.
To understand the scope of the challenge, consider this: In the U.S., more than 984 million doses of Covid-19 vaccine have been distributed so far. Each one needed refrigeration that, even in the U.S., proved challenging. Now extrapolate to all vaccines and the entire world. For Covid, fewer than 73 percent of the global population received even one dose. The need for refrigerated or frozen handling was partially to blame.
Globally, the cold chain packaging market is valued at over $15 billion and is expected to exceed $60 billion by 2033.
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Freeze-drying, also called lyophilization, which is common for many vaccines, isn’t always an option. Many freeze-dried vaccines still need refrigeration, and even medicines approved for storage at ambient temperatures break down in the heat of sub-Saharan Africa. “Even in a freeze-dried state, biologics often will undergo partial rehydration and dehydration, which can be extremely damaging,” Boothby explains.
The cold chain is also very expensive to maintain. The global pharmaceutical cold chain packaging market is valued at more than $15 billion, and is expected to exceed $60 billion by 2033, according to a report by Future Market Insights. This cost is only expected to grow. According to the consulting company Accenture, the number of medicines that require the cold chain are expected to grow by 48 percent, compared to only 21 percent for non-cold-chain therapies.
Tardigrades to the rescue
Tardigrades are only about a millimeter long – with four legs and claws, and they lumber around like bears, thus their nickname – but could provide a big solution. “Tardigrades are unique in the animal kingdom, in that they’re able to survive a vast array of environmental insults,” says Boothby, the Wyoming professor. “They can be dried out, frozen, heated past the boiling point of water and irradiated at levels that are thousands of times more than you or I could survive.” So, his team is gradually unlocking tardigrades’ survival secrets and applying them to biologic pharmaceuticals to make them withstand both extreme heat and desiccation without losing efficacy.
Boothby’s team is focusing on blood clotting factor VIII, which, as the name implies, causes blood to clot. Currently, Boothby is concentrating on the so-called cytoplasmic abundant heat soluble (CAHS) protein family, which is found only in tardigrades, protecting them when they dry out. “We showed we can desiccate a biologic (blood clotting factor VIII, a key clotting component) in the presence of tardigrade proteins,” he says—without losing any of its effectiveness.
The researchers mixed the tardigrade protein with the blood clotting factor and then dried and rehydrated that substance six times without damaging the latter. This suggests that biologics protected with tardigrade proteins can withstand real-world fluctuations in humidity.
Furthermore, Boothby’s team found that when the blood clotting factor was dried and stabilized with tardigrade proteins, it retained its efficacy at temperatures as high as 95 degrees Celsius. That’s over 200 degrees Fahrenheit, much hotter than the 58 degrees Celsius that the World Meteorological Organization lists as the hottest recorded air temperature on earth. In contrast, without the protein, the blood clotting factor degraded significantly. The team published their findings in the journal Nature in March.
Although tardigrades rarely live more than 2.5 years, they have survived in a desiccated state for up to two decades, according to Animal Diversity Web. This suggests that tardigrades’ CAHS protein can protect biologic pharmaceuticals nearly indefinitely without refrigeration or freezing, which makes it significantly easier to deliver them in locations where refrigeration is unreliable or doesn’t exist.
The tricks of the tardigrades
Besides the CAHS proteins, tardigrades rely on a type of sugar called trehalose and some other protectants. So, rather than drying up, their cells solidify into rigid, glass-like structures. As that happens, viscosity between cells increases, thereby slowing their biological functions so much that they all but stop.
Now Boothby is combining CAHS D, one of the proteins in the CAHS family, with trehalose. He found that CAHS D and trehalose each protected proteins through repeated drying and rehydrating cycles. They also work synergistically, which means that together they might stabilize biologics under a variety of dry storage conditions.
“We’re finding the protective effect is not just additive but actually is synergistic,” he says. “We’re keen to see if something like that also holds true with different protein combinations.” If so, combinations could possibly protect against a variety of conditions.
Commercialization outlook
Before any stabilization technology for biologics can be commercialized, it first must be approved by the appropriate regulators. In the U.S., that’s the U.S. Food and Drug Administration. Developing a new formulation would require clinical testing and vast numbers of participants. So existing vaccines and biologics likely won’t be re-formulated for dry storage. “Many were developed decades ago,” says Fox. “They‘re not going to be reformulated into thermo-stable vaccines overnight,” if ever, he predicts.
Extending stability outside the cold chain, even for a few days, can have profound health, environmental and economic benefits.
Instead, this technology is most likely to be used for the new products and formulations that are just being created. New and improved vaccines will be the first to benefit. Good candidates include the plethora of mRNA vaccines, as well as biologic pharmaceuticals for neglected diseases that affect parts of the world where reliable cold chain is difficult to maintain, Boothby says. Some examples include new, more effective vaccines for malaria and for pathogenic Escherichia coli, which causes diarrhea.
Tallying up the benefits
Extending stability outside the cold chain, even for a few days, can have profound health, environmental and economic benefits. For instance, MenAfriVac, a meningitis vaccine (without tardigrade proteins) developed for sub-Saharan Africa, can be stored at up to 40 degrees Celsius for four days before administration. “If you have a few days where you don’t need to maintain the cold chain, it’s easier to transport vaccines to remote areas,” Fox says, where refrigeration does not exist or is not reliable.
Better health is an obvious benefit. MenAfriVac reduced suspected meningitis cases by 57 percent in the overall population and more than 99 percent among vaccinated individuals.
Lower healthcare costs are another benefit. One study done in Togo found that the cold chain-related costs increased the per dose vaccine price up to 11-fold. The ability to ship the vaccines using the usual cold chain, but transporting them at ambient temperatures for the final few days cut the cost in half.
There are environmental benefits, too, such as reducing fuel consumption and greenhouse gas emissions. Cold chain transports consume 20 percent more fuel than non-cold chain shipping, due to refrigeration equipment, according to the International Trade Administration.
A study by researchers at Johns Hopkins University compared the greenhouse gas emissions of the new, oral Vaxart COVID-19 vaccine (which doesn’t require refrigeration) with four intramuscular vaccines (which require refrigeration or freezing). While the Vaxart vaccine is still in clinical trials, the study found that “up to 82.25 million kilograms of CO2 could be averted by using oral vaccines in the U.S. alone.” That is akin to taking 17,700 vehicles out of service for one year.
Although tardigrades’ protective proteins won’t be a component of biologic pharmaceutics for several years, scientists are proving that this approach is viable. They are hopeful that a day will come when vaccines and biologics can be delivered anywhere in the world without needing refrigerators or freezers en route.