Rules needed for commercial spaceflight human studies

Aiming to ensure safe future space travel, a panel of experts proposes four ethical principles to guide human-subjects research.

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New guidelines are needed to ensure that research on human subjects performed on commercial spaceflights is conducted ethically, a panel of experts say in a commentary in the Sept. 28 issue of the journal Science. The article is titled "Ethically cleared to launch?"

Private companies are expected to fly thousands of people into space in the coming decades. The workers and passengers aboard will have the opportunity to participate in research studies. Such research is essential to ensure the safety of future space travelers and often helpful in addressing critical issues of human health, in general.

A man in a blue shirt in an office
Photo by Randy Carnell / UW Medicine UW Medicine neurologist Dr. Michael A. Williams discusses space medicine research ethics.

Buț current ethical rules that govern research on human subjects do not directly address the unique circumstances of research aboard commercial spaceflights, according to a panel convened by the Center for Medical Ethics and Health Policy at Baylor College of Medicine in Houston.

“There has been a long tradition of astronauts from NASA and other national space agencies of volunteering for research, and the agencies have established tradition on how this research is done,” said Dr. Michael A. Williams, professor of neurology and of neurological surgery at the University of Washington School of Medicine in Seattle and one of the paper’s co-authors. “But how such research is going to be done aboard commercial flights, where incentives might be different, hasn’t really been explored.”

The panel calls for formulating guidelines based on four principles. The first of these is social responsibility. Commercial spaceflight is possible because of a substantial public investment, they argue, so research conducted on commercial spaceflights should benefit society at large.

Related: Downloadable, broadcast-ready soundbites with Dr. Michael Williams

Second, research conducted on commercial spaceflights should aim for scientific excellence.

“Poorly designed, duplicative, and low-priority studies beget poor-quality data. They cloud the evidence base, endanger participants, and waste resources,” the authors write.

Third, research aboard commercial spaceflights should adhere to the principle of “proportionality,” which holds research risk should be minimized “to the extent possible, and proportionately balanced in relation to the anticipated benefits of the individual commercial space flight participants and to society.”

Finally, the guidelines should promote the principle of “global stewardship” so that the “benefits of human space exploration be enjoyed by all.”

The authors acknowledge that their guidelines' emphasis on social responsibility differs from other ethical guidelines that prioritize research subjects’ autonomy in deciding whether to participate in a study. But they argue that, because so few individuals are selected for spaceflight, participation should be encouraged.

"All prospective commercial space flight participants should be fully informed about the social value of any proposed research protocols and be encouraged to participate,” they conclude. “Incentivizing participation may be justified, so long as the incentive is calibrated with the risks and does not create undue inducement. Commercial companies may give preference to those  commercial space flight participants willing to participate in research, but further ethical attention is needed to determine whether commercial space flight participants should remain flight eligible even if they decline research participation.”

NASA’s practices may serve as a model, Williams said. “At NASA, for any given mission an individual might be eligible to participate in as many and 40 to 50 studies, but they get to pick and choose the ones they want to participate in. That respects the principle of autonomy.”

The lead author on the Science paper is Vasiliki Rahimzadeh and the senior and corresponding author is Amy L. McGuire, both of Baylor College.

Written by Michael McCarthy

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