My understanding is that simple plasma dilution (plasmapheresis) has the same or better results. Though some of the sources I saw said that a centrifugal plasmapheresis machine is better than the membrane-based machines.
[1] - "The figures are staggering: out of 35,000 children in care, more than 2,000 were physically or sexually abused by priests between 1936 and 1999" (Ireland alone)
[2] - French Church abuse: 216,000 children were victims of clergy - inquiry
That is : periodic blood transfusion from healthy young vegan donor.
It works very well. Rejuvenates ancient billionaires.
Surely it's superpopular among the oligarchs. Probably not the kind of thing you want in the news (vampires!).
The technical term is Parabiosis.
These guys offer the service : https://www.ambrosiaplasma.com/