The Astropharmacy Concept
A system for making medicines on demand
Stephanie Sutton | | Interview
Lynn J Rothschild is a senior research scientist at NASA’s Ames Research Center with a keen interest in evolutionary biology, but more recently she has been involved in creating an “astropharmacy” system that can produce biologic drugs on demand (1). Her work combines pre-programed cells in spore form, genetic engineering, and a small volume system adapted from standard laboratory protocols.
Where did the astropharmacy concept come from?
Around 15 years ago, our Center Director at the time asked me to start a program on synthetic biology, with the idea that it could potentially be a game-changing technology for space exploration.
I met Phil Williams, a professor of pharmacy at the University of Nottingham, when he came to visit a postdoc student at NASA Ames. He was very interested in the work we did, and we came up with the idea of “astropharmacy” – combining my work with the pharmacy field to solve the challenge of delivering pharmaceutical care in space.
What are the unique considerations for spaceflight, particularly in terms of medicines?
It is extremely expensive to launch a spacecraft. A large part of the spacecraft is jettisoned in the first few minutes after take-off because of the sheer amount of fuel required to escape the Earth’s gravity. Saving mass and volume is critical, so astronauts must carefully consider what they take with them. In terms of an astronaut’s health, there are significant medical tests and a quarantine period before someone is allowed to go into space. Health should not be a problem on short-term missions and astronauts are closely monitored. If there was a problem, the astronaut could return to Earth, or a medication could potentially be sent up.
But what about long-term missions? There are plans for a long-term human presence on the moon and, eventually, to send humans to Mars. With current technology, it would take around six months to reach Mars and the astronauts would have to stay a year and a half for the planets to realign to minimize the journey time home. For such a long trip, you cannot possibly pack every potentially useful medicine. It would take up too much mass – and most medicines also have a limited shelf life, which would render them useless part way through the journey.
When NASA put out a call for projects for making drugs on demand, we decided to focus on biologics – and we now have funding from the NASA Innovative Concepts Program. Biologics are extremely expensive and have a very short shelf life, even with refrigeration. However, many of the medical problems that astronauts could potentially face could probably be effectively treated with biologics.
From the point of view of a bioengineer, protein-based drugs are easy to make. If the DNA has the right coding mechanism then it should be possible to get the organisms to synthesize the right protein. Initially, we’ve been working on non-glycosylated biologics, but in principle we should also be able to figure out ways to glycosylate the proteins, and to engineer cells with different metabolic pathways so that we can make other things too besides protein-based drugs.
In collaboration with Phil Williams, we are using the common soil bacterium Bacillus subtilis to secrete the protein-based drugs. Importantly, B. subtilis forms extremely resistant spores that can be dried and stored at room temperature – in fact, B. subtilis spores were able to survive exposure to a space environment for nearly six years on the LDEF mission. I’m actually working with these spores on another mission, PowerCell on Eu:CROPIS – and they are working beautifully!. B. subtilis is already used as a platform for bioengineering, so a lot of the relevant lab tools already exist. Essentially, we just need to program the bacteria, put them in spore form, and then they can be sent into space – potentially on punch outs on a piece of paper, though we are exploring other approaches too. Once reconstituted, they can be used to produce the protein. We are also working on approaches to purification.
What type of equipment would astronauts need to take into space to produce medicines on demand?
To answer this question, I’ll direct you to students who worked on the International Genetically Engineered Machine (IGEM) competition (2). I’ve been working on the astropharmacy system with a team of students from Brown University and Stanford University – and last year we also had some wonderful students from Princeton University. One of the Browns students is also working with me for his Masters – and, incidentally, he is specifically interested in taking the technologies into the pharmaceutical industry. Currently we also have an undergraduate from Yale working on the manufacturing technologies.
The students are working on technologies and approaches for diagnostics, drug production and drug purification – and have come up with technologies for a synthesis system, drug expression chamber, and a purification platform. I’ve been very firm with them that the technology needs to be as small and as simple as possible! Astronauts will want an easy system – preferably something that works at the press of a button. Right now, we have a lab system that requires an external pump and various other components, but I am pushing for us to use microfluidic systems. I can’t give too much away on this at the moment… come back to me in a year! But I will say that we are aiming for something the size of a wallet that doesn’t require an external pump. It will, however, depend on the size of a crew. If we need to make medicines for a crew of five or ten, then a dedicated pump would probably be necessary, but most likely medicines will only be required for one or two individuals. If medicine is needed for something chronic, then we envisage that an astronaut could set up a production day once every three months or so to create a backlog. Other medicines can just be made on demand.
What implications does the astropharmacy have for patients on Earth?
I really believe that a lot of what we do at NASA and in the space industry ultimately has applications for Earth. Pharma companies focus on producing a large number of doses with a high profit. With our system, we have the opposite situation in that we can only produce very few doses – but this is exactly what is needed for some medicines, such as orphan drugs. We’ve had pharma companies approach us before about our work because they are specifically interested in orphan drugs and making personalized medicines on demand.