First HIV Antiretrovirals Manufactured in Space Delivered Back to Earth

For the first time, unique commercial pharmaceuticals produced using the zero gravity of outer space have been returned to Earth. After being stuck in space waiting for clearance to land, a capsule containing the small but extremely valuable cargo of HIV antiretrovirals landed in the desert in the US state of Utah. Drugs produced this way have higher purity and often improved pharmacokinetics, but have been too costly to produce until now.

In June 2023, a miniature pharmaceuticals factory built by Varda Space Industries was launched into Earth orbit. This small space startup company had only been around since 2020 – and the COVID pandemic had inspired them to look for a way to use the unique properties of space to directly benefit the health of people on Earth.

Zero gravity process can give drugs new properties

According to Varda co-founder Delian Asparouhov, gravity has significant effects somewhere between the microscopic scale and the atomic scale. This has beneficial applications in all manner of processes like crystal formation in drug manufacturing. For example, it is possible to give certain solid state pharmaceuticals improved solubility, turning a four-hour intravenous infusion into a couple of subcutaneous injections. The number of oral pills required for a treatment could be reduced. Since treatment compliance is a major obstacle to treatment, such improved drugs could significantly improve outcomes.

There are many drugs that were abandoned simply because administration was too impractical. Zero gravity manufacturing could open up these libraries of discarded drugs, Asparouhov says. It could also be possible to modify certain drugs to cross the blood–brain barrier.

Antiviral Drug Polarized crystals (photographed through a microscope) of the drug 2-3 dideoxyadenosine, also known as ddA, a drug that is closely related to AZT or azidothymidine. The antiviral effect of ddA against HIV was discovered at the National Cancer Institute. Credit: Larry Ostby (Photographer), National Cancer Institute, National Institutes of Health

Onboard the small space factory is a pharmaceutical manufacturing system designed to produce ritonavir, an antiretroviral which was initially used to treat HIV. This early antiretroviral has a number of notorious gastrointestinal and metabolic side effects. In 1998, there was a major production crisis when it was discovered that were production defects in the the oral form stemming from crystallisation problems.

Nowadays, ritonavir has been surpassed by newer antiretroviral drugs for the treatment of HIV but has been investigated for cancer treatment and during the pandemic received emergency use authorisation for COVID treatment. The samples retrieved from the capsule will only be used for evaluation purposes, to help inform the production of other pharmaceuticals.

Producing drug proteins in space is nothing new. This has been done on space stations for decades – however, these were for research purposes in developing drugs and understanding biological processes. It is only now that technology has advanced to the point where it has become cheap enough to use the unique environment of outer space to manufacture high-value products.

The capsule with its onboard factory is specially designed to be recovered and reused to minimise costs. This has only been possible thanks to rockets becoming vastly cheaper. NASA’s space shuttle cost US$65 400 for each kilogram of cargo launched into space. Today, SpaceX’s Falcon 9 rocket costs a mere 4% of that, with costs set to fall further.

Such breakneck technological development was bound to run into a snag – this one consisting of red tape. The agency that regulates commercial air and spaceflight, the Federal Aviation Administration (FAA) gave Varda a licence for their payload to be launched, but not for the capsule to re-enter the atmosphere. The vast majority of satellites don’t have to worry about that, simply burning up in the atmosphere when they can no longer function. The FAA is obviously concerned about a large module returning intact but out of control.

Eventually, after more than six months of delays and looking at alternatives such as landing in Australia instead, Varda was able to secure a re-entry permit for 21st February and its capsule returned to Earth under a parachute in the Utah desert.

Asparouhov envisions a time when much larger orbital factories produce pharmaceuticals and other valuable materials in orbit.