Novel Technologies Could Make Coronavirus Vaccines More Stable for Worldwide Shipping
The vaccine from Pfizer will need to be stored at minus 70 degrees Celsius for worldwide distribution.
Ssendi Bosco has long known to fear the rainy season. As deputy health officer of Mubende District, a region in Central Uganda, she is only too aware of the threat that heavy storms can pose to her area's fragile healthcare facilities.
In early October, persistent rain overwhelmed the power generator that supplies electricity to most of the region, causing a blackout for three weeks. The result was that most of Mubende's vaccine supplies against diseases such as tuberculosis, diphtheria, and polio went to waste. "The vaccines need to be constantly refrigerated, so the generator failing means that most of them are now unusable," she says.
This week, the global fight against the coronavirus pandemic received a major boost when Pfizer and their German partner BioNTech released interim results showing that their vaccine has proved more than 90 percent effective at preventing participants in their clinical trial from getting COVID-19.
But while Pfizer has already signed deals to supply the vaccine to the U.S., U.K., Canada, Japan and the European Union, Mubende's recent plight provides an indication of the challenges that distributors will face when attempting to ship a coronavirus vaccine around the globe, particularly to low-income nations.
Experts have estimated that somewhere between 12 billion and 15 billion doses will be needed to immunize the world's population against COVID-19, a staggering scale, and one that has never been attempted before. "The logistics of distributing COVID-19 vaccines have been described as one of the biggest challenges in the history of mankind," says Göran Conradson, managing director of Swedish vaccine manufacturer Ziccum.
But even these estimates do not take into account the potential for vaccine spoilage. Every year, the World Health Organization estimates that over half of the world's vaccines end up being wasted. This happens because vaccines are fragile products. From the moment they are made, to the moment they are administered, they have to be kept within a tightly controlled temperature range. Throughout the entire supply chain – transportation to an airport, the flight to another country, unloaded, distribution via trucks to healthcare facilities, and storage – they must be refrigerated at all times. This is known as the cold chain, and one tiny slip along the way means the vaccines are ruined.
"It's a chain, and any chain is only as strong as its weakest link," says Asel Sartbaeva, a chemist working on vaccine technologies at the University of Bath in the U.K.
For COVID-19, the challenge is even greater because some of the leading vaccine candidates need to be kept at ultracold temperatures. Pfizer's vaccine, for example, must be kept at -70 degrees Celsius, the kind of freezer capabilities rarely found outsides of specialized laboratories. Transporting such a vaccine across North America and Europe will be difficult enough, but supplying it to some of the world's poorest nations in Asia, Africa and South America -- where only 10 percent of healthcare facilities have reliable electricity -- might appear virtually impossible.
But technology may be able to come to the rescue.
Making Vaccines Less Fragile
Just as the world's pharmaceutical companies have been racing against the clock to develop viable COVID-19 vaccine candidates, scientists around the globe have been hastily developing new technologies to try and make vaccines less fragile. Some approaches involve various chemicals that can be added to the vaccine to make them far more resilient to temperature fluctuations during transit, while others focus on insulated storage units that can maintain the vaccine at a certain temperature even if there is a power outage.
Some of these concepts have already been considered for several years, but before COVID-19 there was less of a commercial incentive to bring them to market. "We never felt that there is a need for an investment in this area," explains Sam Kosari, a pharmacist at the University of Canberra, who researches the vaccine cold chain. "Some technologies were developed then to assist with vaccine transport in Africa during Ebola, but since that outbreak was contained, there hasn't been any serious initiative or reward to develop this technology further."
In her laboratory at the University of Bath, Sartbaeva is using silica - the main constituent of sand – to encase the molecular components within a vaccine. Conventional vaccines typically contain protein targets from the virus, which the immune system learns to recognize. However, when they are exposed to temperature changes, these protein structures degrade, and lose their shape, making the vaccine useless. Sartbaeva compares this to how an egg changes its shape and consistency when it is boiled.
When silica is added to a vaccine, it molds to each protein, forming little protective cages around them, and thus preventing them from being affected by temperature changes. "The whole idea is that if we can create a shell around each protein, we can protect it from physically unravelling which is what causes the deactivation of the vaccine," she says.
Other scientists are exploring similar methods of making vaccines more resilient. Researchers at the Jenner Institute at the University of Oxford recently conducted a clinical trial in which they added carbohydrates to a dengue vaccine, to assess whether it became easier to transport.
Both research groups are now hoping to collaborate with the COVID-19 vaccine candidates being developed by AstraZeneca and Imperial College, assuming they become available in 2021.
"It's good we're all working on this big problem, as different methods could work better for different types of COVID-19 vaccines," says Sartbaeva. "I think it will be needed."
Next-Generation Vaccine Technology
While these different technologies could be utilized to try and protect the first wave of COVID-19 vaccines, efforts are also underway to develop completely new methods of vaccination. Much of this research is still in its earliest stages, but it could yield a second generation of COVID-19 vaccine candidates in 2022 and beyond.
"After the first round of mass vaccination, we could well observe regional outbreaks of the disease appearing from time to time in the coming years," says Kosari. "This is the time where new types of vaccines could be helpful."
One novel method being explored by Ziccum and others is dry powder vaccines. The idea is to spray dry the final vaccine into a powder form, where it is more easily preserved and does not require any special cooling while being transported or stored. People then receive the vaccine by inhaling it, rather than having it injected into their bloodstream.
Conradson explains that the concept of dry powder vaccines works on the same principle as dried food products. Because there is no water involved, the vaccine's components are far less affected by temperature changes. "It is actually the water that leads to the destruction of potency of a vaccine when it gets heated," he says. "We're looking to develop a dry powder vaccine for COVID-19 but this will be a second-generation vaccine. At the moment there are more than 200 first-generation candidates, all of which are using conventional technologies due to the timeframe pressures, which I think was the correct decision."
Dry powder COVID-19 vaccines could also be combined with microneedle patches, to allow people to self-administer the vaccine themselves in their own home. Microneedles are miniature needles – measured in millionths of a meter – which are designed to deliver medicines through the skin with minimal pain. So far, they have been used mainly in cosmetic products, but many scientists are working to use them to deliver drugs or vaccines.
At Georgia Institute of Technology in Atlanta, Mark Prausnitz is leading a couple of projects looking at incorporating COVID-19 vaccines into microneedle patches with the hope of running some early-stage clinical trials over the next couple of years. "The advantage is that they maintain the vaccine in a stable, dry state until it dissolves in the skin," he explains.
Prausnitz and others believe that once the first generation of COVID-19 vaccines become available, biotech and pharmaceutical companies will show more interest in adapting their products so they can be used in a dried form or with a microneedle patch. "There is so much pressure to get the COVID vaccine out that right now, vaccine developers are not interested in incorporating a novel delivery method," he says. "That will have to come later, once the pressure is lessened."
The Struggle of Low-Income Nations
For low-income nations, time will only tell whether technological advancements can enable them to access the first wave of licensed COVID-19 vaccines. But reports already suggest that they are in danger of becoming an afterthought in the race to procure vaccine supplies.
While initiatives such as COVAX are attempting to make sure that vaccine access is equitable, high and middle-income countries have already inked deals to secure 3.8 billion doses, with options for another 5 billion. One particularly sobering study by the Duke Global Health Innovation Center has suggested that such hoarding means many low-income nations may not receive a vaccine until 2024.
For Bosco and the residents of Mubende District in Uganda, all they can do is wait. In the meantime, there is a more pressing problem: fixing their generators. "We hope that we can receive a vaccine," she says. "But the biggest problem will be finding ways to safely store it. Right now we cannot keep any medicines or vaccines in the conditions they need, because we don't have the funds to repair our power generators."
After his grandmother’s dementia diagnosis, one man invented a snack to keep her healthy and hydrated.
Founder Lewis Hornby and his grandmother Pat, sampling Jelly Drops—an edible gummy containing water and life-saving electrolytes.
On a visit to his grandmother’s nursing home in 2016, college student Lewis Hornby made a shocking discovery: Dehydration is a common (and dangerous) problem among seniors—especially those that are diagnosed with dementia.
Hornby’s grandmother, Pat, had always had difficulty keeping up her water intake as she got older, a common issue with seniors. As we age, our body composition changes, and we naturally hold less water than younger adults or children, so it’s easier to become dehydrated quickly if those fluids aren’t replenished. What’s more, our thirst signals diminish naturally as we age as well—meaning our body is not as good as it once was in letting us know that we need to rehydrate. This often creates a perfect storm that commonly leads to dehydration. In Pat’s case, her dehydration was so severe she nearly died.
When Lewis Hornby visited his grandmother at her nursing home afterward, he learned that dehydration especially affects people with dementia, as they often don’t feel thirst cues at all, or may not recognize how to use cups correctly. But while dementia patients often don’t remember to drink water, it seemed to Hornby that they had less problem remembering to eat, particularly candy.
Where people with dementia often forget to drink water, they're more likely to pick up a colorful snack, Hornby found. alzheimers.org.uk
Hornby wanted to create a solution for elderly people who struggled keeping their fluid intake up. He spent the next eighteen months researching and designing a solution and securing funding for his project. In 2019, Hornby won a sizable grant from the Alzheimer’s Society, a UK-based care and research charity for people with dementia and their caregivers. Together, through the charity’s Accelerator Program, they created a bite-sized, sugar-free, edible jelly drop that looked and tasted like candy. The candy, called Jelly Drops, contained 95% water and electrolytes—important minerals that are often lost during dehydration. The final product launched in 2020—and was an immediate success. The drops were able to provide extra hydration to the elderly, as well as help keep dementia patients safe, since dehydration commonly leads to confusion, hospitalization, and sometimes even death.
Not only did Jelly Drops quickly become a favorite snack among dementia patients in the UK, but they were able to provide an additional boost of hydration to hospital workers during the pandemic. In NHS coronavirus hospital wards, patients infected with the virus were regularly given Jelly Drops to keep their fluid levels normal—and staff members snacked on them as well, since long shifts and personal protective equipment (PPE) they were required to wear often left them feeling parched.
In April 2022, Jelly Drops launched in the United States. The company continues to donate 1% of its profits to help fund Alzheimer’s research.
Theupcoming vaccine is changing the way we look at treating one of the country’s deadliest cancers.
Last week, researchers at the University of Oxford announced that they have received funding to create a brand new way of preventing ovarian cancer: A vaccine. The vaccine, known as OvarianVax, will teach the immune system to recognize and destroy mutated cells—one of the earliest indicators of ovarian cancer.
Understanding Ovarian Cancer
Despite advancements in medical research and treatment protocols over the last few decades, ovarian cancer still poses a significant threat to women’s health. In the United States alone, more than 12,0000 women die of ovarian cancer each year, and only about half of women diagnosed with ovarian cancer survive five or more years past diagnosis. Unlike cervical cancer, there is no routine screening for ovarian cancer, so it often goes undetected until it has reached advanced stages. Additionally, the primary symptoms of ovarian cancer—frequent urination, bloating, loss of appetite, and abdominal pain—can often be mistaken for other non-cancerous conditions, delaying treatment.
An American woman has roughly a one percent chance of developing ovarian cancer throughout her lifetime. However, these odds increase significantly if she has inherited mutations in the BRCA1 or BRCA2 genes. Women who carry these mutations face a 46% lifetime risk for ovarian and breast cancers.
An Unlikely Solution
To address this escalating health concern, the organization Cancer Research UK has invested £600,000 over the next three years in research aimed at creating a vaccine, which would destroy cancerous cells before they have a chance to develop any further.
Researchers at the University of Oxford are at the forefront of this initiative. With funding from Cancer Research UK, scientists will use tissue samples from the ovaries and fallopian tubes of patients currently battling ovarian cancer. Using these samples, University of Oxford scientists will create a vaccine to recognize certain proteins on the surface of ovarian cancer cells known as tumor-associated antigens. The vaccine will then train that person’s immune system to recognize the cancer markers and destroy them.
The next step
Once developed, the vaccine will first be tested in patients with the disease, to see if their ovarian tumors will shrink or disappear. Then, the vaccine will be tested in women with the BRCA1 or BRCA2 mutations as well as women in the general population without genetic mutations, to see whether the vaccine can prevent the cancer altogether.
While the vaccine still has “a long way to go,” according to Professor Ahmed Ahmed, Director of Oxford University’s ovarian cancer cell laboratory, he is “optimistic” about the results.
“We need better strategies to prevent ovarian cancer,” said Ahmed in a press release from the University of Oxford. “Currently, women with BRCA1/2 mutations are offered surgery which prevents cancer but robs them of the chance to have children afterward.
Teaching the immune system to recognize the very early signs of cancer is a tough challenge. But we now have highly sophisticated tools which give us real insights into how the immune system recognizes ovarian cancer. OvarianVax could offer the solution.”