Karmazin claims most participants see improvements within a month of getting the $8,000 one-time infusion of a two litre bagful of plasma, which is blood with the blood cells removed. But many scientists and clinicians say Karmazin’s trial is so poorly designed it cannot hope to provide evidence about the effects of the transfusions. Some also say the pay-top-articipate study, with the potential to collect up to $4.8 million from as many as 600 participants, amounts to a scam.
The procedure is based on some intriguing but inconclusive science. Over the last decade or so, such studies have offered provocative clues that certain hallmarks of ageing can be reversed or accelerated when old mice get blood from young ones. Yet these studies have come to conflicting conclusions. Further, the experiments offer little insight into how Ambrosia’s one-time infusions will affect people because the mouse experiments were done over nearly four weeks.
Use of young blood to treat disease has been explored in other clinical trials also. In 2014, Stanford University neuroscientist Tony Wyss-Coray showed that old mice had increased neuron growth and improved memory after about 10 infusions of blood from young mice. But he is not convinced about the Ambrosia trials. “People want to believe that young blood restores youth, even though we don’t have evidence that it works in humans and we don’t understand the mechanism of how mice look younger.”
Risk is the ultimate question when it comes to the ethics of Ambrosia’s trial. Although blood transfusions are considered safe for people who need them to survive, side effects can include hives, lung injury, or even deadly infections.