Nearly a decade before the first space shuttle left Earth, NASA wanted to make drugs in space. In a 1970 internal document, the agency suggested that the microgravity environment of space could be conducive to manufacturing and testing the efficacy of different kinds of pharmaceuticals.

Gravity poses logistical challenges for scientists working in the lab. On Earth, heavier materials sink to the bottom of test tubes and often clump together. In microgravity, however, the proteins that are needed to create medicine overcome these challenges and can grow freely. When working with proteins and cells in space, the purity of experiments can increase.

When the United States’ shuttle program was first proposed, the plan was to launch as many as 50 flights a year. The cost of this ambitious idea needed to be justified. It was suggested by NASA that perhaps astronauts working on the shuttle could work on a cure for cancer. Or discover a treatment for Parkinson’s. The possibilities were endless.

In 1982, NASA partnered with McDonnell Douglas (now Boeing). McDonnell Douglas designed a machine to test a process called electrophoresis, which is a way to separate macromolecules when studying DNA and RNA. Early results suggested that the space environment would make the experiment purification processes more efficient.

Rather than having NASA astronauts test the company’s machine, McDonnell Douglas proposed to NASA that the company send one of their own employees to work on the shuttle. Surprisingly, NASA said yes. Charlie Walker, the chief test engineer who helped build the machine, was selected, and became the first civilian to go to space. He recalls the company’s confidence in their research: “We took [the results] to NASA and they said if the company is willing to invest in [sending me to space] then we are willing to partner,” he tells Medium.

With two flights to space, Walker made history, but shortly after, in 1986, the Challenger shuttle exploded, killing the crew onboard. As a result of the devastating loss, private companies, that initially wanted to send their employees into space for research purposes, pulled back.

But today, the International Space Station (ISS) is fully operational, and typically has six members aboard who spend their days doing scientific research, like the testing of medical equipment, 3D printing, and even growing plants. Drug discovery is also now back in action.

In 2018, a company called Angiex Inc. was one of the lucky private drug companies to send an experiment up to the station. The principal investigator of the Angiex experiment, Shou-Ching Jaminet, is a molecular biologist and former researcher at Harvard Medical School. She’s studying the effects that microgravity has on endothelial cells, the types of cells that line our blood vessels.

“Part of the motivation… is driven by the need to understand whether a mission crew could make their own drugs in space, if needed.”

In space, blood vessel cells don’t grow as well as they do on Earth, which might explain why astronauts have higher rates of cardiovascular problems. Angiex is working on a cancer therapy drug that destroys blood vessels in tumors. “We wanted to see if endothelial cells in microgravity are spared by our drug,” says Jaminet. Their research has implications for cancer treatment on Earth, and to help maintain the health of astronauts in space.

“Most other cell types are not that sensitive to microgravity… but blood vessel cells are different and that might explain some of the observations of astronauts health,” says Jaminet. “[Like why] they have higher rates of cardiovascular disease, even though they are generally healthier than the rest of us.”

She and her team got to watch their drug testing experiment live when astronaut Dr. Serena M. Auñón-Chancellor conducted it on board. Angiex only recently received their experiment results and the team is still in the middle of analyzing the data, but so far, Jaminet says they are pleased with the process.

Not everyone is confident that there’s money to be made in manufacturing drugs in space. “I don’t believe in any of it,” says John Logsdon, a space historian and former member of NASA’s advisory council. “I’m a skeptic that there is a pot of gold related to microgravity research. There are other commercial things to do with space but this particular idea has been tested enough to suggest that it is not really true.”

Others disagree. “I definitely think it’s cool and necessary,” says Walker. “I believe there will be numerous successes in our pursuits in terms of medical research and even corporate research.”

Ken Savin, director of the Center For Advancement and Science In Space (CASIS), which manages the ISS U.S. National Laboratory, agrees. “These companies are doing experiments and looking at research that they just couldn’t do on earth,” he says. Sure, research facilities on Earth try to mimic lesser gravity’s effect on cells, but ultimately if you really want to know what your experiment will be like in microgravity, you have to go to space.

Even if space-based drug discovery doesn’t turn out to be profitable, there remain benefits. Drugs stored on the space station have a much shorter shelf life than those stored on Earth, and only so much stock can be placed on a spacecraft. Part of the motivation for allowing pharmaceutical research to continue on the ISS is driven by the need to understand whether a mission crew could make their own drugs in space, if needed. Long-duration space missions are decades away, but should crews visit Mars as anticipated, they will likely stay for several months, not to mention that the round-trip to Mars takes over a year. Understanding how treatments behave in microgravity gives NASA insight into the best ways to keep future astronauts safe.