There is a drug granting Regeneration power, costs 1.200 pr. dose I think.
But you have to be ON the drug when the damage occurs.
"will gradually regenerate back to its original living form. A
wooden homunculus grows leaves and roots, for example, while a
corpse regains the semblance of life."
The blurb in citation marks are from Street Magic's description on the special Free Spirit version of the Regeneration power, and describes what happens when such a spirit posesses a vessel.
So I guess that actual regeneration of a living person could be attained through the posession of a Free Spirit with this power.
If used on a corpse... And then kicking the spirit out and kickstarting the heart, if this would return the person to life or simply have a living veggie (due to the braindamage sustained until the spirit entered and started regeneraton), is going to be up to the GM I suppose.
Ugh, creepy stuff.