Department of Energy microsphere technology repurposed as an oral drug delivery system

August 19, 2021
Porous wall hollow glass microspheres. Photograph provided by Dr. William D. Hill.
Low-power image of microspheres, courtesy of the Applied Research Center.

SpheroFill, a company co-founded by MUSC researcher William Hill, Ph.D., is helping to convert swords into plowshares with more than a quarter million dollars in funding from a National Science Foundation (NSF) Small Business Technology Transfer grant. Hill is a professor of Pathology and Laboratory Medicine at MUSC and a research scientist at the Ralph H. Johnson VA Medical Center.

Hill and SpheroFill are developing microsphere technology to create a unique oral drug delivery platform that will allow for protected, controlled release of drugs over time. The microsphere technology was originally created for strategic purposes by the Department of Energy at the Savannah River National Laboratory (SRNL) and then converted for civilian purposes by the Applied Research Center (ARC) in Aiken, South Carolina.

"A microsphere is about a third the diameter of a human hair. You can actually load the microspheres with different cargos, drugs in this case, and then control the release rate of materials coming out of them.”

-- Dr. William Hill

The other co-founders of SpheroFill are George Wicks, Ph.D., of ARC, and ENT-otolaryngologist  Paul Weinberger, M.D. Wicks co-invented the microsphere technology while at the SRNL. Together with MUSC and ARC, the three inventors have submitted a patent on the oral and other drug delivery approaches.

Hill, who serves as the company’s executive vice president and chief scientific officer, is excited about the collaboration between SpheroFill, MUSC and ARC.

“The Applied Research Center is a nonprofit research and development organization established to transfer technology from the SRNL and academic institutions and to assist start-up companies where possible,” explained Hill. “It is the value of the taxpayers’ investment being amplified into novel uses that can create new jobs and expand the economy of South Carolina. ARC’s goal is to build a technology base in Aiken County and the state. Importantly, ARC has been a key initial investor for us.” 

The microspheres are hollow spheres with a large cargo capacity contained by a porous silica glass outer shell. Complex nanoscale channels connect the interior cargos with the outside world.

“A microsphere is about a third the diameter of a human hair,” said Hill. “You can actually load the microspheres with different cargos, drugs in this case, and then control the release rate of materials coming out of them.”

Dr. William Hill, executive vice president, chief scientific officer and one of the co-founders of SpheroFill 
Dr. William Hill, one of the co-founders of SpheroFill, in his laboratory at MUSC.

Once in the body, the microspheres will release the drug as the outer coating degrades and the nanopores open. The technology could help pharmaceutical companies overcome a serious hurdle in developing oral drugs. Drugs taken by mouth often break down in the harsh environment of the gastrointestinal system.

“SpheroFill allows patients to have effective drug dosing over extended time, so the patient only has to take the drug once or possibly twice.”

-- Dr. William Hill

“The pharmaceutical industry has a large number of drugs that are difficult to deliver orally – either because they don't dissolve very well in the aqueous system that we have in our gastrointestinal tract, or because they are very reactive and will be broken down very quickly by enzymes there,” said Hill.

By encasing the drugs, the microspheres protect them from this harsh environment and enable them to reach their target locations, where they release their contents. As a result, less drug is wasted, which is a savings for both pharmaceutical companies and consumers. This will be particularly important with expensive drugs and newer sensitive biological drugs.

The technology not only allows more efficient delivery of existing oral drugs, but it also makes possible the oral delivery of new types of drugs.

“There is also an ability to deliver drugs in ways that they never could have been delivered before, such as in gaseous form” said Hill. “We're trying to develop new ways to deliver agents that aren't really drugs now because they're just too difficult to use as drugs.”

The outer shell of a porous wall hollow glass microsphere. Photograph provided by Dr. William D. Hill.  
Cross-section of the microsphere's porous wall. Image courtesy of the Applied Research Center.

The technology could also help patients with better medication compliance. Many drugs, such as antibiotics, must be taken daily over several days. When patients begin feeling better, they may discontinue taking the medication prematurely, leading to drug resistance and other problems.

“SpheroFill allows patients to have effective drug dosing over extended time, so the patient only has to take the drug once or possibly twice,” said Hill.

At MUSC, Hill’s research team is working on testing different polymers that can serve as coatings for the microspheres, with the aim of having different drug-release rates with different coatings, ranging from days to months. 

“The cool thing is that you can have microspheres with different thicknesses of coatings or entirely different coatings, which will release materials at different rates,” said Hill. “And we can mix them together to have overlapping or sequential releases of the same or different drugs for an extended period of time,” said Hill.

The team is working on controlling drug release by measuring release rates for different coatings. Once Hill and his team complete this step, they will next study how well the microspheres with the different coatings work as a drug-delivery platform, first in animals and then in humans.

 Hill believes that the support from the NSF is an important milestone for Spherofill and is grateful to the MUSC Foundation for Research Development for its help with the application.

“It’s exciting to get this stamp of approval from the NSF,” said Hill. This hard-to-acquire support says that it believes the technology and the company are worth the investment to help with technical development and assistance through its strong commercialization infrastructure. This will also help to open doors for us to partners and customers.”

In addition to improving drug delivery, SpheroFill and its partners also hope to support the South Carolina economy by bringing research and development, high-tech and pharmaceutical jobs to Charleston, Aiken and other areas of the state.  

U.S. Sen. Lindsey Graham and U.S. Rep. Joe Wilson see that economic potential.

“The funding will allow SpheroFill to create advancements in the medical field, and I appreciate NSF working to help turn this into a reality,” said Graham.

 Wilson, too, acknowledged the NSF’s generous funding of SpheroFill’s valuable collaboration.

 “The synergy between SpheroFill, the Applied Research Center and the Savannah River National Laboratory has allowed this research to gain momentum, providing transformative opportunities in medical treatments,” said Wilson. “I am grateful that NSF recognized and rewarded the talent here in our community.”

 About America’s Seed Fund

America’s Seed Fund, powered by the National Science Foundation (NSF), awards $200 million annually to startups and small businesses, transforming scientific discovery into products and services with commercial and societal impact. Startups working across almost all areas of science and technology can receive up to $2 million in non-dilutive funds to support research and development (R&D), helping de-risk technology for commercial success.