If protein drugs are made in oil solutions, they could be stored at room temperature

A new storage technology can ensure the stability of protein-based drugs and vaccines in the absence of refrigeration. The discovery, made by researchers at the University of Pennsylvania, could eliminate the need to refrigerate hundreds of life-saving drugs such as insulin, monoclonal antibodies and viral vaccines.

“More than 80 percent of biologic drugs and 90 percent of vaccines need temperature control. With this new approach, we can revolutionize their storage and distribution, making them more accessible to everyone,” said Scott Medina, study leader and professor of biomedical engineering at the University of Pennsylvania. “This will save billions of dollars currently spent on keeping the supply chain of these products cold, and potentially enable the use of protein therapeutics in settings where continuous refrigeration is not possible.”

The results of the study were recently published in the journal Nature Communications. In a series of experiments, the research team replaced an aqueous solution commonly used in protein drugs with perfluorocarbon oil and tested five different proteins with different medical functions, such as antibodies and enzymes.

When tested on mice, the researchers found that the new solution was as effective as the refrigerated versions and showed no signs of toxicity, meaning there were no negative health effects from using the oil solution.

The researchers also found that the oil-based solution was perfectly sterile when handling the protein samples, eliminating the possibility of contamination by bacteria, fungi or viruses that need an aqueous environment to grow and survive.

But there was one problem: In an aqueous medium, proteins are evenly distributed throughout the liquid. In oil, they are not as soluble. So the team developed a surfactant, a molecule that coats the surface of the protein so it can spread evenly throughout the solution.

The surfactant also creates a protective shell around the protein, keeping it stable and preventing it from breaking down even at the temperature at which water would normally boil.

“Think of it like a raincoat for proteins,” says Medina, “Just like a raincoat protects you from moisture, the protective shell protects the protein from heat and contamination, allowing it to remain stable and functional.

Protein-based drugs and vaccines are typically sensitive to heat, light and movement, all of which can cause them to lose their structure and functionality over time. Cooling helps slow this degradation process, so the drug remains effective until it is administered.

The results of this study could lead to a reduction or complete elimination of cold chain logistics, which is the supply chain network needed to get drugs from the point of manufacture to various distribution centers before administration to patients.

In 2020, another group of researchers found that cold chain logistics are projected to cost $58 billion worldwide by 2026.

The researchers say their approach has the potential to reduce costs and barriers for pharmaceutical companies, which could lead to greater savings and better access to drugs for patients who need these therapies.

“This new method could also lower barriers and allow drugs to be distributed in resource-limited settings to all populations,” Medina says.  “We could even use it for those on the battlefield where these drugs are needed but access to refrigerators is limited.”

In the future, the researchers intend to demonstrate that their method works with other proteins and to collaborate with pharmaceutical companies to stabilize protein molecules or peptides that can be used in various drugs.