Manufacturing Drugs and Tissue in Orbit Is Getting Real

For decades, growing crystals and cells in orbit was purely an academic exercise, a curiosity astronauts tended to between other duties on the International Space Station. That’s starting to change. A handful of companies now believe space is ready to become something closer to a factory floor.

Turning Decades of ISS Research Into an Industry

Maturing space labs and cheaper launches are fueling efforts to manufacture drugs and tissues in orbit, according to reporting in the journal Science by Michael Greshko. Across academia and industry, researchers are trying to transform decades of biomedical experiments aboard the International Space Station into a genuine manufacturing enterprise, betting that microgravity can improve not just pharmaceutical production, but the growth of stem cells, implants, miniature organs, and other living materials.

Kate Rubins, a former NASA astronaut who conducted some of this early research herself and now directs the University of Pittsburgh’s Trivedi Institute for Space and Global Biomedicine, has watched the field evolve considerably. The ISS has become a sophisticated orbital laboratory, complete with automated microscopes, standardized workflows, and a growing understanding of how cells and molecules behave in microgravity. For certain applications, Rubins says, microgravity “could be a useful new variable.”

Why Gravity Gets in the Way on Earth

The basic physics behind this push is straightforward. On Earth, gravity drives bubbling convection in liquids and causes crystals and particles to settle unevenly as they form. Those effects can make pharmaceutical crystals inconsistent in size and structure. In microgravity, without that settling and convection, crystals can grow purer, more uniform, or in forms that simply won’t take shape under Earth’s gravity at all.

That principle isn’t new. Researchers have studied protein crystallization in space since the Skylab era in the 1970s, and NASA has run crystallization experiments on the ISS for decades. What has changed recently is the ability to act on those insights commercially, largely because reusable rockets have made reaching orbit dramatically cheaper and more frequent than it used to be.

A Capsule That Doesn’t Need a Space Station

Varda Space Industries, founded in 2021, has emerged as one of the most visible companies pursuing this bet. In just five years, the company has designed, built, and launched six capsules into orbit. Unlike earlier space-based pharmaceutical research, Varda’s autonomous capsules don’t require the ISS at all. Miniature onboard laboratories melt, dissolve, cool, and recrystallize pharmaceutical compounds independently in orbit before parachuting back down to Earth.

Varda’s approach has already produced tangible results. The company successfully grew crystals of ritonavir, an antiviral medication known for how differently its various crystal structures behave in the body, during its first mission, and has launched further missions since. According to Michael Reilly, Varda’s chief strategy officer, the company expects one of its capsules to be capable of processing enough drug material for a clinical trial involving hundreds of patients within the next couple of years. “Our focus is really getting a space drug, in this case, one that we’ve manufactured in microgravity, into people,” Reilly said.

Other Companies Racing Into the Same Orbit

Varda is far from alone. In 2025, longtime ISS payload developer Redwire Space announced a partnership with the startup ExesaLibero Pharma to grow ultrapure crystals of an experimental bone drug in space, intended to seed larger crystal batches back on Earth. Around the same time, the UK-based startup BioOrbit launched its own payload to the ISS, designed, like Varda’s capsules, to autonomously crystallize drugs in microgravity.

Pharmaceutical giants have been laying groundwork for this shift for years as well. Merck has used ISS-based experiments to study crystallization of complex biologic drugs, including work relevant to its cancer immunotherapy pembrolizumab, sold under the brand name Keytruda. In one ISS experiment, microgravity conditions produced a much more uniform crystal size distribution than matched ground-based control experiments, exactly the kind of consistency that matters for drug manufacturing and formulation.

Beyond Drugs: Growing Tissue in Zero Gravity

The ambitions extend well past drug crystals. Microgravity’s effects on how cells stack, grow, and interact are also drawing serious interest from researchers working on tissue engineering and regenerative medicine. Because there’s no gravity pulling newly placed cells out of position, microgravity makes it easier to layer tissue and have it hold its intended shape.

In April 2024, Redwire Space’s BioFabrication Facility aboard the ISS successfully bioprinted living cardiac tissue and returned it safely to Earth, marking a notable step toward one day producing lab-grown tissue as an alternative to donated organs for transplant. Redwire has also previously used the same facility to bioprint an artificial meniscus, and the company’s next goal is to bioprint human blood vessels in orbit.

The Heart Cells That Started It All

Some of this current work traces back to a landmark 2016 investigation. As a graduate student, Arun Sharma, working with Stanford’s Joseph Wu, sent human heart muscle cells derived from induced pluripotent stem cells, or iPSCs, to the ISS, where astronaut Kate Rubins examined them using the station’s microgravity glovebox. It was the first study to examine heart function at the cellular level in microgravity, rather than looking only at the heart as a whole organ, as earlier cardiovascular studies had done.

That 2016 experiment showed iPSC-derived heart muscle cells could serve as an accurate, functioning model for studying cardiac behavior in space, laying groundwork for a wave of subsequent stem cell research aboard the station, including work on 3D neural organoids modeling Parkinson’s disease and multiple sclerosis. Because iPSCs can be coaxed into transforming into nearly any cell type in the human body, researchers view them as a uniquely flexible resource for regenerative medicine, one that microgravity research may help refine further.

Space as a Factory Floor, Not Just a Laboratory

What separates this current moment from decades of earlier ISS science is the shift in ambition. Where previous research mainly asked what happens to cells and crystals in microgravity, companies like Varda, Redwire, and BioOrbit are now asking whether those effects can be captured, scaled, and turned into repeatable manufacturing processes.

Whether that vision holds up at commercial scale remains to be proven. But between cheaper access to orbit, an increasingly sophisticated body of ISS research, and companies now racing to commercialize specific applications, from antiviral crystals to bioprinted cardiac tissue, the idea of space as pharmaceutical infrastructure has moved considerably closer to something researchers can actually test, rather than simply imagine.

Sources

Science