Suspended animation is being trialed by trauma teams at University of Maryland Medical Centre in Baltimore, with results to be released later in 2020:
However in this context the process is for temporary emergency suspension. Whether it can extended to healthy subjects for indefinite periods of time is as yet unknown, but the field is busily being investigated for spaceflight applications.
“Universe Today” reported on the latest in human hibernation aka “induced torpor” for this purpose: If Astronauts Hibernated on Long Journeys, They’d Need Smaller Spacecraft
An ESA Ideas discussion which prompted the Universe Today news bite: Hibernating astronauts would need smaller spacecraft
ESA Advanced Concepts Team discussion which naturally produced a summary in an academic (i.e. pay for it) book. Additionally there’s a lot of journal work gathering around the concept.
A small sample from the PubMed links…
Hibernating astronauts-science or fiction?
Hibernation for space travel: Impact on radioprotection.
The effects of hibernation and forced disuse (neurectomy) on bone properties in arctic ground squirrels. Directly space related despite the bioscience sounding title.
Thus a ‘watch this space’ for a burgeoning biomedical application to the problem of supporting long-duration missions.